shinkan-jinkendo/frontend/src/components/exercises/ExerciseFormPageRoot.jsx

import React, { useEffect, useState, useRef, useMemo, useCallback } from 'react'
import { useNavigate, useParams, Link } from 'react-router-dom'
import api, { buildExerciseApiPayload } from '../../utils/api'
import { resolveExerciseMediaFileUrl, resolveMediaAssetFileUrl } from '../../utils/exerciseMediaUrl'
import RichTextEditor from '../RichTextEditor'
import ExerciseProgressionGraphPanel from '../ExerciseProgressionGraphPanel'
import ExerciseMediaThumbTile from '../ExerciseMediaThumbTile'
import MediaPreviewModal from '../MediaPreviewModal'
import ReportContentModal from '../ReportContentModal'
import CombinationMethodProfileEditor from '../CombinationMethodProfileEditor'
import ExercisePickerModal from '../ExercisePickerModal'
import {
  SHINKAN_EXERCISE_MEDIA_DRAG_MIME,
  buildExerciseMediaDragPayload,
} from '../../utils/exerciseInlineMediaRefs'
import { autoScrollForDragNearEdges } from '../../utils/dragAutoScroll'
import { SKILL_LEVEL_OPTIONS, normalizeSkillLevelSlug } from '../../constants/skillLevels'
import { useAuth } from '../../context/AuthContext'
import { useToast } from '../../context/ToastContext'
import {
  activeClubMemberships,
  getDefaultClubIdForGovernanceForms,
  getTenantClubDependencyKey,
} from '../../utils/activeClub'
import { COMBINATION_ARCHETYPE_OPTIONS, ARCHETYPE_DEFAULT_REP_SERIES_COUNT, defaultRepSeriesCountForArchetype } from '../../constants/combinationArchetypes'
import { readSlotProfilesV1, normalizeAdvanceMode, parseComboRepSeriesCountUi } from '../../utils/combinationMethodProfileUi'
import { GripVertical } from 'lucide-react'
import UnsavedChangesPrompt from '../UnsavedChangesPrompt'
import { useBeforeUnloadWhen, useUnsavedChangesBlocker } from '../../hooks/useUnsavedChangesBlocker'

const INTENSITY_OPTIONS = [
  { value: '', label: '—' },
  { value: 'niedrig', label: 'niedrig' },
  { value: 'mittel', label: 'mittel' },
  { value: 'hoch', label: 'hoch' },
]

const VARIANT_DIFFICULTY = [
  { value: '', label: '—' },
  { value: 'easier', label: 'Einfacher' },
  { value: 'same', label: 'Gleich' },
  { value: 'harder', label: 'Schwerer' },
  { value: 'adapted', label: 'Angepasst' },
]

/** HTML5-DnD für Kombi-Stationen (Reihenfolge = Ablauf). */
const DND_EXERCISE_COMBO_STATION = 'application/x-shinkan-exercise-combo-station-v1'

/** Pro Station meist 1 Übung; bis zu 3 wenn kurzer Auswahl-Pool sinnvoll ist. */
const MAX_COMBO_CANDIDATES_PER_STATION = 3

const comboTinyNumberInputSx = {
  width: '3.5rem',
  maxWidth: '100%',
  padding: '4px 6px',
  fontSize: '0.8125rem',
  textAlign: 'center',
}

function emptyComboSlotRow() {
  return {
    title: '',
    candidate_exercise_ids: [],
    exercise_title_by_id: {},
    advance_mode: 'timed',
    load_sec: '',
    consecutive_reps: '',
    rep_series_count: '1',
    intra_rep_rest_sec: '',
    transition_after_sec: '',
  }
}

function comboSlotsFromDetail(exercise) {
  const raw = exercise?.combination_slots
  const arch = exercise?.method_archetype != null ? String(exercise.method_archetype).trim() : ''
  const serienFallback = defaultRepSeriesCountForArchetype(arch)
  const mp =
    exercise?.method_profile &&
    typeof exercise.method_profile === 'object' &&
    !Array.isArray(exercise.method_profile)
      ? exercise.method_profile
      : {}
  const spvList = readSlotProfilesV1(mp)
  const byIx = new Map(spvList.map((r) => [Number(r.slot_index), r]))

  if (!Array.isArray(raw) || raw.length === 0) {
    return [emptyComboSlotRow()]
  }
  const sorted = [...raw].sort((a, b) => (Number(a.slot_index) || 0) - (Number(b.slot_index) || 0))
  return sorted.map((s) => {
    const si = Number(s.slot_index)
    const st = byIx.get(si) || {}
    const cands = Array.isArray(s.candidate_exercise_ids)
      ? s.candidate_exercise_ids.map((x) => Number(x)).filter((n) => Number.isFinite(n))
      : []
    const mode = normalizeAdvanceMode(st.advance_mode)
    let repSer = ''
    if (st.rep_series_count != null) repSer = String(st.rep_series_count)
    else if (mode === 'rep' || mode === 'manual') repSer = String(serienFallback)
    else repSer = '1'
    return {
      title: s.title != null ? String(s.title) : '',
      candidate_exercise_ids: cands,
      exercise_title_by_id: {},
      advance_mode: mode,
      load_sec: st.load_sec != null ? String(st.load_sec) : '',
      consecutive_reps: st.consecutive_reps != null ? String(st.consecutive_reps) : '',
      rep_series_count: repSer,
      intra_rep_rest_sec: st.intra_rep_rest_sec != null ? String(st.intra_rep_rest_sec) : '',
      transition_after_sec: st.transition_after_sec != null ? String(st.transition_after_sec) : '',
    }
  })
}

function emptyVariantDraft() {
  return {
    variant_name: '',
    description: '',
    execution_changes: '',
    duration_min: '',
    duration_max: '',
    equipment_lines: '',
    difficulty_adjustment: '',
    progression_level: 1,
    prerequisite_variant_id: '',
  }
}

function apiVariantToRow(v) {
  let lines = ''
  const eq = v.equipment_changes
  if (Array.isArray(eq)) {
    lines = eq.join('\n')
  } else if (typeof eq === 'string' && eq.trim()) {
    try {
      const p = JSON.parse(eq)
      lines = Array.isArray(p) ? p.join('\n') : eq
    } catch {
      lines = eq
    }
  }
  return {
    ...v,
    duration_min: v.duration_min ?? '',
    duration_max: v.duration_max ?? '',
    equipment_lines: lines,
    progression_level: v.progression_level ?? 1,
    prerequisite_variant_id: v.prerequisite_variant_id ?? '',
    difficulty_adjustment: v.difficulty_adjustment ?? '',
  }
}

function buildVariantPayloadFromRow(row) {
  const lines = (row.equipment_lines || '')
    .split(/[\n,]+/)
    .map((s) => s.trim())
    .filter(Boolean)
  const pl =
    row.progression_level === '' || row.progression_level == null
      ? 1
      : parseInt(row.progression_level, 10)
  const so =
    row.sequence_order === '' || row.sequence_order == null
      ? null
      : parseInt(row.sequence_order, 10)
  return {
    variant_name: (row.variant_name || '').trim(),
    description: (row.description || '').trim() || null,
    execution_changes: (row.execution_changes || '').trim() || null,
    duration_min: row.duration_min === '' || row.duration_min == null ? null : parseInt(row.duration_min, 10),
    duration_max: row.duration_max === '' || row.duration_max == null ? null : parseInt(row.duration_max, 10),
    equipment_changes: lines,
    difficulty_adjustment: row.difficulty_adjustment || null,
    progression_level: Number.isNaN(pl) ? 1 : pl,
    sequence_order: so !== null && Number.isNaN(so) ? null : so,
    prerequisite_variant_id:
      row.prerequisite_variant_id === '' || row.prerequisite_variant_id == null
        ? null
        : parseInt(row.prerequisite_variant_id, 10),
  }
}

/** Gemeinsame Felder für „Variante bearbeiten“ und „Neue Variante“. */
function ExerciseVariantFields({
  row,
  onPatch,
  prerequisiteOthers,
  rteMinHeight = '110px',
  inlineExerciseId,
  linkedExerciseMedia = [],
  onExerciseMediaListChanged,
}) {
  return (
    <>
      <div className="form-row">
        <label className="form-label">Variantenname *</label>
        <input
          type="text"
          className="form-input"
          value={row.variant_name || ''}
          onChange={(e) => onPatch({ variant_name: e.target.value })}
          minLength={3}
        />
      </div>
      <div className="form-row">
        <label className="form-label">Kurzbeschreibung</label>
        <textarea
          className="form-input"
          rows={2}
          value={row.description || ''}
          onChange={(e) => onPatch({ description: e.target.value })}
        />
      </div>
      <div className="form-row">
        <label className="form-label">Abweichungen zur Durchführung</label>
        <RichTextEditor
          value={row.execution_changes || ''}
          onChange={(html) => onPatch({ execution_changes: html })}
          placeholder="Was unterscheidet diese Variante? (Listen über Symbolleiste)"
          minHeight={rteMinHeight}
          inlineExerciseId={inlineExerciseId}
          linkedExerciseMedia={linkedExerciseMedia}
          onExerciseMediaListChanged={onExerciseMediaListChanged}
        />
      </div>
      <div style={{ display: 'grid', gridTemplateColumns: '1fr 1fr', gap: '10px' }}>
        <div className="form-row">
          <label className="form-label">Dauer Min</label>
          <input
            type="number"
            className="form-input"
            value={row.duration_min}
            onChange={(e) => onPatch({ duration_min: e.target.value })}
          />
        </div>
        <div className="form-row">
          <label className="form-label">Dauer Max</label>
          <input
            type="number"
            className="form-input"
            value={row.duration_max}
            onChange={(e) => onPatch({ duration_max: e.target.value })}
          />
        </div>
      </div>
      <div className="form-row">
        <label className="form-label">Materialänderungen (eine Zeile pro Eintrag)</label>
        <textarea
          className="form-input"
          rows={2}
          value={row.equipment_lines || ''}
          onChange={(e) => onPatch({ equipment_lines: e.target.value })}
          placeholder="+ Pratzen"
        />
      </div>
      <div style={{ display: 'grid', gridTemplateColumns: 'repeat(auto-fit, minmax(160px, 1fr))', gap: '10px' }}>
        <div className="form-row">
          <label className="form-label">Schwere relativ</label>
          <select
            className="form-input"
            value={row.difficulty_adjustment || ''}
            onChange={(e) => onPatch({ difficulty_adjustment: e.target.value })}
          >
            {VARIANT_DIFFICULTY.map((o) => (
              <option key={o.label} value={o.value}>
                {o.label}
              </option>
            ))}
          </select>
        </div>
        <div className="form-row">
          <label className="form-label">Progressions-Stufe (1–10)</label>
          <input
            type="number"
            min={1}
            max={10}
            className="form-input"
            value={row.progression_level}
            onChange={(e) =>
              onPatch({
                progression_level: e.target.value === '' ? '' : parseInt(e.target.value, 10),
              })
            }
          />
        </div>
        <div className="form-row">
          <label className="form-label">Voraussetzungs-Variante</label>
          <select
            className="form-input"
            value={
              row.prerequisite_variant_id === '' || row.prerequisite_variant_id == null
                ? ''
                : String(row.prerequisite_variant_id)
            }
            onChange={(e) =>
              onPatch({
                prerequisite_variant_id: e.target.value === '' ? '' : parseInt(e.target.value, 10),
              })
            }
          >
            <option value="">— keine —</option>
            {prerequisiteOthers.map((o) => (
              <option key={o.id} value={o.id}>
                {o.variant_name || `Variante #${o.id}`}
              </option>
            ))}
          </select>
        </div>
      </div>
    </>
  )
}

function emptyForm() {
  return {
    title: '',
    summary: '',
    goal: '',
    execution: '',
    preparation: '',
    trainer_notes: '',
    equipmentLines: '',
    duration_min: '',
    duration_max: '',
    group_size_min: '',
    group_size_max: '',
    focus_areas_multi: [],
    training_styles_multi: [],
    training_types_multi: [],
    target_groups_multi: [],
    visibility: 'private',
    club_id: null,
    status: 'draft',
    skills: [],
    exercise_kind: 'simple',
    method_archetype: '',
    method_profile_json: '{}',
    combination_slots: [emptyComboSlotRow()],
  }
}

function detailToForm(exercise) {
  return {
    title: exercise.title || '',
    summary: exercise.summary || '',
    goal: exercise.goal || '',
    execution: exercise.execution || '',
    preparation: exercise.preparation || '',
    trainer_notes: exercise.trainer_notes || '',
    equipmentLines: (exercise.equipment || []).join('\n'),
    duration_min: exercise.duration_min ?? '',
    duration_max: exercise.duration_max ?? '',
    group_size_min: exercise.group_size_min ?? '',
    group_size_max: exercise.group_size_max ?? '',
    focus_areas_multi: (exercise.focus_areas || []).map((f) => ({
      focus_area_id: f.focus_area_id,
      is_primary: !!f.is_primary,
    })),
    training_styles_multi: (exercise.training_styles || []).map((t) => ({
      training_style_id: t.training_style_id,
      is_primary: !!t.is_primary,
    })),
    training_types_multi: (exercise.training_types || []).map((t) => ({
      training_type_id: t.training_type_id,
      is_primary: !!t.is_primary,
    })),
    target_groups_multi: (exercise.target_groups || []).map((g) => ({
      target_group_id: g.target_group_id,
      is_primary: !!g.is_primary,
    })),
    visibility: exercise.visibility || 'private',
    club_id:
      String(exercise.visibility || '').trim().toLowerCase() === 'club' &&
      exercise.club_id != null &&
      exercise.club_id !== ''
        ? Number(exercise.club_id)
        : null,
    status: exercise.status || 'draft',
    skills:
      exercise.skills?.map((s) => ({
        skill_id: s.skill_id,
        is_primary: s.is_primary || false,
        intensity: s.intensity || '',
        required_level: normalizeSkillLevelSlug(s.required_level),
        target_level: normalizeSkillLevelSlug(s.target_level),
      })) || [],
    exercise_kind:
      String(exercise.exercise_kind || 'simple').toLowerCase() === 'combination'
        ? 'combination'
        : 'simple',
    method_archetype: exercise.method_archetype != null ? String(exercise.method_archetype) : '',
    method_profile_json:
      typeof exercise.method_profile === 'object' &&
      exercise.method_profile != null &&
      !Array.isArray(exercise.method_profile)
        ? JSON.stringify(exercise.method_profile, null, 2)
        : '{}',
    combination_slots: comboSlotsFromDetail(exercise),
  }
}

function MultiAssocBlock({ title, rows, setRows, options, idKey, emptyLabel }) {
  const setPrimary = (idx) => {
    setRows(rows.map((r, i) => ({ ...r, is_primary: i === idx })))
  }
  const updateRow = (idx, patch) => {
    const next = rows.map((r, i) => (i === idx ? { ...r, ...patch } : r))
    if (patch.is_primary === true) {
      next.forEach((r, i) => {
        if (i !== idx) r.is_primary = false
      })
    }
    setRows(next)
  }
  const addRow = () => setRows([...rows, { [idKey]: '', is_primary: rows.length === 0 }])
  const removeRow = (idx) => {
    const next = rows.filter((_, i) => i !== idx)
    if (next.length && !next.some((r) => r.is_primary)) next[0].is_primary = true
    setRows(next)
  }

  return (
    <div className="multi-assoc-block">
      <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', gap: '8px' }}>
        <h3>{title}</h3>
        <button type="button" className="btn btn-secondary" style={{ fontSize: '12px', padding: '4px 10px' }} onClick={addRow}>
          + Eintrag
        </button>
      </div>
      {rows.length === 0 && (
        <p style={{ fontSize: '13px', color: 'var(--text2)', margin: 0 }}>{emptyLabel}</p>
      )}
      {rows.map((row, idx) => (
        <div key={idx} className="multi-assoc-row">
          <select
            className="form-input"
            value={row[idKey] || ''}
            onChange={(e) => updateRow(idx, { [idKey]: e.target.value ? parseInt(e.target.value, 10) : '' })}
          >
            <option value="">— wählen —</option>
            {options.map((o) => (
              <option key={o.id} value={o.id}>
                {o.icon ? `${o.icon} ` : ''}
                {o.name}
                {o.abbreviation ? ` (${o.abbreviation})` : ''}
              </option>
            ))}
          </select>
          <label style={{ display: 'flex', alignItems: 'center', gap: '4px', fontSize: '13px', whiteSpace: 'nowrap' }}>
            <input
              type="radio"
              name={`primary-${idKey}`}
              checked={!!row.is_primary}
              onChange={() => setPrimary(idx)}
            />
            primär
          </label>
          <button type="button" className="btn" style={{ fontSize: '12px', padding: '4px 8px' }} onClick={() => removeRow(idx)}>
            ✕
          </button>
        </div>
      ))}
    </div>
  )
}

function ExerciseFormPageRoot() {
  const { id: routeId } = useParams()
  const navigate = useNavigate()
  const { user } = useAuth()
  const isSuperadmin = user?.role === 'superadmin'
  const isPlatformAdmin = user?.role === 'admin' || user?.role === 'superadmin'
  const tenantClubDepKey = useMemo(() => getTenantClubDependencyKey(user), [user])

  const [clubsForGovernanceForms, setClubsForGovernanceForms] = useState([])
  useEffect(() => {
    if (!isPlatformAdmin) {
      setClubsForGovernanceForms([])
      return undefined
    }
    let cancelled = false
    ;(async () => {
      try {
        const list = await api.listClubs()
        if (!cancelled) setClubsForGovernanceForms(Array.isArray(list) ? list : [])
      } catch {
        if (!cancelled) setClubsForGovernanceForms([])
      }
    })()
    return () => {
      cancelled = true
    }
  }, [isPlatformAdmin, tenantClubDepKey])

  const membershipClubRows = useMemo(() => activeClubMemberships(user?.clubs), [user?.clubs])

  /** Plattform-Admin: alle Vereine; sonst nur Mitgliedschafts-Vereine. */
  const visibilityClubChoices = useMemo(() => {
    if (isPlatformAdmin && clubsForGovernanceForms.length > 0) {
      return [...clubsForGovernanceForms].sort((a, b) =>
        String(a.name || '').localeCompare(String(b.name || ''), 'de'),
      )
    }
    return [...membershipClubRows].sort((a, b) =>
      String(a.name || '').localeCompare(String(b.name || ''), 'de'),
    )
  }, [isPlatformAdmin, clubsForGovernanceForms, membershipClubRows])

  const governanceDefaultClubId = useMemo(() => getDefaultClubIdForGovernanceForms(user), [user])

  const exerciseId = routeId && !Number.isNaN(parseInt(routeId, 10)) ? parseInt(routeId, 10) : null
  const isEdit = exerciseId != null

  const [formData, setFormData] = useState(emptyForm)
  const [skillsCatalog, setSkillsCatalog] = useState([])
  const [focusAreas, setFocusAreas] = useState([])
  const [styleDirections, setStyleDirections] = useState([])
  const [trainingTypes, setTrainingTypes] = useState([])
  const [targetGroups, setTargetGroups] = useState([])
  const [mediaList, setMediaList] = useState([])
  const [loading, setLoading] = useState(!!isEdit)
  const [saving, setSaving] = useState(false)
  const [formDirty, setFormDirty] = useState(false)
  const [skillPick, setSkillPick] = useState('')

  const toast = useToast()
  const allowUnloadBlock = Boolean(formDirty && !loading && !saving)
  useBeforeUnloadWhen(allowUnloadBlock)
  const blocker = useUnsavedChangesBlocker(allowUnloadBlock)
  const [variants, setVariants] = useState([])
  const [variantDraft, setVariantDraft] = useState(() => emptyVariantDraft())
  const [variantSavingId, setVariantSavingId] = useState(null)
  const [variantBusy, setVariantBusy] = useState(false)
  const [variantEditSelection, setVariantEditSelection] = useState(null)
  const variantsDetailsRef = useRef(null)

  const [mediaFields, setMediaFields] = useState({})
  const [mediaSavingId, setMediaSavingId] = useState(null)
  const [archiveOpen, setArchiveOpen] = useState(false)
  const [archiveQ, setArchiveQ] = useState('')
  const [archiveLoading, setArchiveLoading] = useState(false)
  const [archiveItems, setArchiveItems] = useState([])
  const [archiveError, setArchiveError] = useState(null)
  const [mediaPreview, setMediaPreview] = useState(null)
  const [reportTarget, setReportTarget] = useState(null)

  useEffect(() => {
    const next = {}
    for (const m of mediaList) {
      next[m.id] = {
        title: m.title || '',
      }
    }
    setMediaFields(next)
  }, [mediaList])

  useEffect(() => {
    const onDragOverDoc = (e) => {
      const types = e.dataTransfer?.types ? Array.from(e.dataTransfer.types) : []
      if (!types.includes(SHINKAN_EXERCISE_MEDIA_DRAG_MIME)) return
      e.preventDefault()
      autoScrollForDragNearEdges(e)
    }
    document.addEventListener('dragover', onDragOverDoc)
    return () => document.removeEventListener('dragover', onDragOverDoc)
  }, [])



  useEffect(() => {
    if (!archiveOpen) return undefined
    let cancelled = false
    const t = setTimeout(async () => {
      setArchiveLoading(true)
      setArchiveError(null)
      try {
        const res = await api.listMediaAssets({
          q: archiveQ.trim() || undefined,
          limit: 40,
        })
        if (!cancelled) setArchiveItems((res.items || []).filter(a => !a.legal_hold_active))
      } catch (e) {
        if (!cancelled) setArchiveError(e.message || String(e))
      } finally {
        if (!cancelled) setArchiveLoading(false)
      }
    }, 280)
    return () => {
      cancelled = true
      clearTimeout(t)
    }
  }, [archiveOpen, archiveQ])

  useEffect(() => {
    let cancelled = false
    const boot = async () => {
      try {
        const [skillsData, faData, sdData, ttData, tgData] = await Promise.all([
          api.listSkills(),
          api.listFocusAreas(),
          api.listTrainingStyles(),
          api.listTrainingTypes(),
          api.listTargetGroups(),
        ])
        if (cancelled) return
        setSkillsCatalog(skillsData)
        setFocusAreas(faData)
        setStyleDirections(sdData)
        setTrainingTypes(ttData)
        setTargetGroups(tgData)
      } catch (e) {
        if (!cancelled) {
          console.error(e)
          toast.error(
            'Kataloge (Fokus, Stile, Zielgruppen, Fähigkeiten) konnten nicht geladen werden: ' +
              (e.message || e),
          )
        }
      }
    }
    boot()
    return () => {
      cancelled = true
    }
  }, [toast])

  useEffect(() => {
    if (!isEdit) {
      setFormData(emptyForm())
      setMediaList([])
      setVariants([])
      setVariantDraft(emptyVariantDraft())
      setVariantEditSelection(null)
      setFormDirty(false)
      setLoading(false)
      return
    }
    let cancelled = false
    const load = async () => {
      setLoading(true)
      try {
        const exercise = await api.getExercise(exerciseId)
        if (cancelled) return
        setFormData(detailToForm(exercise))
        setMediaList(exercise.media || [])
        setVariants((exercise.variants || []).map(apiVariantToRow))
        setVariantDraft(emptyVariantDraft())
        setVariantEditSelection(null)
        setFormDirty(false)
      } catch (err) {
        if (!cancelled) {
          toast.error(err.message || 'Übung nicht ladbar')
          navigate('/exercises')
        }
      } finally {
        if (!cancelled) setLoading(false)
      }
    }
    load()
    return () => {
      cancelled = true
    }
  }, [isEdit, exerciseId, navigate, toast])

  useEffect(() => {
    if (variantEditSelection == null || variantEditSelection === 'new') return
    if (!variants.some((v) => v.id === variantEditSelection)) {
      setVariantEditSelection(null)
    }
  }, [variants, variantEditSelection])

  useEffect(() => {
    if (variantEditSelection != null && variantsDetailsRef.current) {
      variantsDetailsRef.current.open = true
    }
  }, [variantEditSelection])

  const updateFormField = (field, value) => {
    setFormDirty(true)
    setFormData((prev) => ({ ...prev, [field]: value }))
  }

  useEffect(() => {
    if (formData.visibility !== 'club') return
    const choices = visibilityClubChoices
    if (!choices.length) return

    const id =
      formData.club_id != null && formData.club_id !== '' ? Number(formData.club_id) : NaN
    const hasValid =
      Number.isFinite(id) && id > 0 && choices.some((c) => Number(c.id) === id)

    if (hasValid) return

    const fallback = governanceDefaultClubId
    const next =
      fallback != null &&
      Number.isFinite(Number(fallback)) &&
      choices.some((c) => Number(c.id) === Number(fallback))
        ? Number(fallback)
        : Number(choices[0].id)

    setFormData((prev) => {
      if (prev.visibility !== 'club') return prev
      if (prev.club_id != null && Number(prev.club_id) === next) return prev
      return { ...prev, club_id: next }
    })
  }, [
    formData.visibility,
    formData.club_id,
    visibilityClubChoices,
    governanceDefaultClubId,
  ])

  const [comboStationPickerIx, setComboStationPickerIx] = useState(null)
  const [comboDropTargetIx, setComboDropTargetIx] = useState(null)

  const reorderCombinationSlots = (fromI, toBeforeIx) => {
    setFormDirty(true)
    setFormData((prev) => {
      const rows = [...(prev.combination_slots || [])]
      if (fromI < 0 || fromI >= rows.length) return prev
      const [moved] = rows.splice(fromI, 1)
      let insertAt = toBeforeIx
      if (fromI < toBeforeIx) insertAt = toBeforeIx - 1
      insertAt = Math.max(0, Math.min(insertAt, rows.length))
      rows.splice(insertAt, 0, moved)
      return { ...prev, combination_slots: rows }
    })
  }

  const patchComboSlotRow = (idx, patch) => {
    setFormDirty(true)
    setFormData((prev) => {
      const rows = [...(prev.combination_slots || [])]
      if (!rows[idx]) return prev
      rows[idx] = { ...rows[idx], ...patch }
      return { ...prev, combination_slots: rows }
    })
  }

  const removeCandidateFromSlot = (slotIdx, exerciseId) => {
    setFormDirty(true)
    setFormData((prev) => {
      const rows = [...(prev.combination_slots || [])]
      const row = rows[slotIdx]
      if (!row) return prev
      const nextIds = (row.candidate_exercise_ids || []).filter((id) => Number(id) !== Number(exerciseId))
      const labels = row.exercise_title_by_id && typeof row.exercise_title_by_id === 'object' ? { ...row.exercise_title_by_id } : {}
      delete labels[Number(exerciseId)]
      rows[slotIdx] = { ...row, candidate_exercise_ids: nextIds, exercise_title_by_id: labels }
      return { ...prev, combination_slots: rows }
    })
  }

  const mergePickedExercisesIntoSlot = (slotIdx, pickedList) => {
    if (!Array.isArray(pickedList) || !pickedList.length) return
    const rowNow = (formData.combination_slots || [])[slotIdx] || emptyComboSlotRow()
    const existingIds = Array.isArray(rowNow.candidate_exercise_ids)
      ? rowNow.candidate_exercise_ids.map((n) => Number(n)).filter((n) => Number.isFinite(n))
      : []
    const ordered = [...existingIds]
    pickedList.forEach((ex) => {
      if (ex?.id == null) return
      const id = Number(ex.id)
      if (!Number.isFinite(id)) return
      if (!ordered.includes(id)) ordered.push(id)
    })
    let nextIds = ordered
    if (nextIds.length > MAX_COMBO_CANDIDATES_PER_STATION) {
      toast.info(
        `Pro Station höchstens ${MAX_COMBO_CANDIDATES_PER_STATION} Übungen — üblich eine feste Übung; zwei bis drei nur als kleiner Wechsel‑Pool. Überschüssige Auswahl wurde abgeschnitten.`,
      )
      nextIds = nextIds.slice(0, MAX_COMBO_CANDIDATES_PER_STATION)
    }
    setFormDirty(true)
    setFormData((prev) => {
      const rows = [...(prev.combination_slots || [])]
      const row = rows[slotIdx] || emptyComboSlotRow()
      const labels =
        row.exercise_title_by_id && typeof row.exercise_title_by_id === 'object' ? { ...row.exercise_title_by_id } : {}
      pickedList.forEach((ex) => {
        if (ex && ex.id != null) {
          const id = Number(ex.id)
          const t = (ex.title || '').trim()
          if (t) labels[id] = t
        }
      })
      rows[slotIdx] = { ...row, candidate_exercise_ids: nextIds, exercise_title_by_id: labels }
      return { ...prev, combination_slots: rows }
    })
  }

  const addSkillRow = () => {
    const id = skillPick ? parseInt(skillPick, 10) : null
    if (!id) {
      toast.error('Fähigkeit wählen')
      return
    }
    if (formData.skills.some((s) => s.skill_id === id)) {
      toast.info('Bereits zugeordnet')
      return
    }
    updateFormField('skills', [
      ...formData.skills,
      {
        skill_id: id,
        is_primary: formData.skills.length === 0,
        intensity: '',
        required_level: '',
        target_level: '',
      },
    ])
    setSkillPick('')
  }

  const setSkillPrimary = (idx) => {
    updateFormField(
      'skills',
      formData.skills.map((s, i) => ({ ...s, is_primary: i === idx })),
    )
  }

  const updateSkillField = (idx, field, value) => {
    updateFormField(
      'skills',
      formData.skills.map((s, i) => (i === idx ? { ...s, [field]: value } : s)),
    )
  }

  const removeSkillRow = (idx) => {
    const next = formData.skills.filter((_, i) => i !== idx)
    if (next.length && !next.some((s) => s.is_primary)) next[0].is_primary = true
    updateFormField('skills', next)
  }

  const performSaveAttempt = useCallback(
    async ({ fromUnsavedDialog = false } = {}) => {
      if (!formData.title || formData.title.trim().length < 3) {
        toast.error('Titel mindestens 3 Zeichen')
        return false
      }
      const payloadBase = {
        ...formData,
        equipment:
          typeof formData.equipmentLines === 'string'
            ? formData.equipmentLines
                .split(/[\n,]+/)
                .map((s) => s.trim())
                .filter(Boolean)
            : [],
      }
      let payload
      try {
        payload = buildExerciseApiPayload(payloadBase)
      } catch (err) {
        toast.error(err.message)
        return false
      }
      setSaving(true)
      try {
        if (isEdit) {
          const saveOnce = (extras = {}) =>
            api.updateExercise(exerciseId, buildExerciseApiPayload(payloadBase, extras))
          try {
            await saveOnce()
          } catch (firstErr) {
            if (
              firstErr.status === 422 &&
              firstErr.code === 'OFFICIAL_MEDIA_LIFECYCLE' &&
              firstErr.payload?.media_assets
            ) {
              toast.error(
                'Speichern nicht möglich: mindestens ein verknüpftes Medium ist nicht aktiv (Papierkorb). ' +
                  'Bitte Medium wiederherstellen oder aus der Übung entfernen.',
              )
              throw firstErr
            }
            if (firstErr.status === 422 && firstErr.code === 'OFFICIAL_MEDIA_CONFIRM_REQUIRED') {
              const promo = (firstErr.payload.assets_need_visibility_promotion || []).length
              const miss = (firstErr.payload.assets_missing_copyright || []).length
              let msg = 'Die Übung ist oder wird offiziell. '
              if (promo > 0) {
                msg += `${promo} verknüpfte Datei(en) werden dabei plattformweit („offiziell“) freigegeben. `
              }
              if (miss > 0) {
                msg += `${miss} Datei(en) haben noch keinen ausreichenden Copyright-Vermerk (mind. 3 Zeichen). `
              }
              msg += 'Fortfahren?'
              if (!window.confirm(msg)) throw firstErr
              let defaultCopyright = ''
              if (miss > 0) {
                defaultCopyright = window.prompt(
                  'Copyright-Vermerk für betroffene Dateien ohne Eintrag (mind. 3 Zeichen):',
                  '© ',
                )
                if (!defaultCopyright || String(defaultCopyright).trim().length < 3) {
                  toast.error('Mindestens 3 Zeichen für den Copyright-Vermerk.')
                  throw firstErr
                }
              }
              await saveOnce({
                promote_attached_media_for_official: true,
                ...(miss > 0 ? { default_official_media_copyright: String(defaultCopyright).trim() } : {}),
              })
            } else if (
              firstErr.status === 422 &&
              firstErr.code === 'CLUB_MEDIA_COPYRIGHT_REQUIRED' &&
              firstErr.payload?.media_assets
            ) {
              const miss = firstErr.payload.media_assets.length
              const msg =
                `Vereinsöffentliche Übungen brauchen bei jeder verknüpften Datei einen Copyright-Vermerk (mind. 3 Zeichen). ` +
                `${miss} Datei(en) sind noch ohne ausreichenden Vermerk. ` +
                `Beim Speichern einen gemeinsamen Vermerk für diese Dateien setzen?`
              if (!window.confirm(msg)) throw firstErr
              const defaultCopyright = window.prompt(
                'Copyright-Vermerk für die betroffenen Dateien (mind. 3 Zeichen):',
                '© ',
              )
              if (!defaultCopyright || String(defaultCopyright).trim().length < 3) {
                toast.error('Mindestens 3 Zeichen für den Copyright-Vermerk.')
                throw firstErr
              }
              await saveOnce({
                default_club_media_copyright: String(defaultCopyright).trim(),
              })
            } else if (firstErr.status === 422 && firstErr.code === 'CLUB_MEDIA_LIFECYCLE') {
              toast.error(
                'Speichern nicht möglich: mindestens ein verknüpftes Medium ist nicht aktiv (Papierkorb). Bitte reaktivieren oder entfernen.',
              )
              throw firstErr
            } else {
              throw firstErr
            }
          }
          const ex = await api.getExercise(exerciseId)
          setMediaList(ex.media || [])
          setVariants((ex.variants || []).map(apiVariantToRow))
          setFormDirty(false)
          toast.success('Gespeichert.')
          return true
        }
        const created = await api.createExercise(payload)
        setFormDirty(false)
        toast.success('Übung angelegt.')
        if (!fromUnsavedDialog) {
          navigate(`/exercises/${created.id}/edit`, { replace: true })
        }
        return true
      } catch (err) {
        toast.error('Fehler beim Speichern: ' + err.message)
        return false
      } finally {
        setSaving(false)
      }
    },
    [exerciseId, formData, isEdit, navigate, toast],
  )

  const handleSubmit = async (e) => {
    e.preventDefault()
    await performSaveAttempt({ fromUnsavedDialog: false })
  }

  const handleUnsavedDialogSave = async () => {
    const ok = await performSaveAttempt({ fromUnsavedDialog: true })
    if (ok) blocker.proceed()
  }

  const refreshMedia = async () => {
    if (!exerciseId) return
    const ex = await api.getExercise(exerciseId)
    setMediaList(ex.media || [])
  }

  const attachFromArchive = async (assetId) => {
    if (!exerciseId) return
    try {
      await api.attachExerciseMediaFromAsset(exerciseId, {
        media_asset_id: assetId,
        context: 'ablauf',
        title: '',
        description: '',
        is_primary: false,
      })
      setArchiveOpen(false)
      await refreshMedia()
    } catch (e) {
      toast.error(e.message || String(e))
    }
  }

  const linkedArchiveAssetIds = useMemo(
    () => new Set((mediaList || []).map((m) => m.media_asset_id).filter(Boolean)),
    [mediaList],
  )

  const handleDeleteMedia = async (mid) => {
    if (
      !confirm(
        'Dieses Medium aus der Übung entfernen? Nur die Verknüpfung wird gelöscht. Die Datei bleibt im Archiv, solange sie noch woanders genutzt wird.\n\n' +
          'Hinweis: Wenn dieser Eintrag noch als Platzhalter im Fließtext steht, zeigt die Vorschau [Medium nicht verfügbar] oder das Speichern der Übung schlägt fehl, bis der Platzhalter entfernt ist.',
      )
    ) {
      return
    }
    try {
      const res = await api.deleteExerciseMedia(exerciseId, mid)
      await refreshMedia()
      const oid = res?.orphan_media_asset_id
      if (oid != null) {
        if (
          confirm(
            'Dieses Archiv-Medium wird danach nirgendwo mehr verwendet. In den Papierkorb (Stufe 1) legen? (Später in der Medienverwaltung wiederherstellbar.)',
          )
        ) {
          await api.postMediaAssetLifecycle(oid, 'trash_soft')
          await refreshMedia()
        }
      }
    } catch (err) {
      toast.error(err.message)
    }
  }

  const moveMediaRow = async (idx, dir) => {
    if (!exerciseId) return
    const j = idx + dir
    if (j < 0 || j >= mediaList.length) return
    const next = [...mediaList]
    const tmp = next[idx]
    next[idx] = next[j]
    next[j] = tmp
    try {
      await api.reorderExerciseMedia(
        exerciseId,
        next.map((x) => x.id),
      )
      setMediaList(next)
    } catch (e) {
      toast.error(e.message || String(e))
    }
  }

  const saveMediaMeta = async (mid) => {
    if (!exerciseId) return
    const fld = mediaFields[mid]
    if (!fld) return
    setMediaSavingId(mid)
    try {
      await api.updateExerciseMedia(exerciseId, mid, {
        title: fld.title.trim() || null,
      })
      await refreshMedia()
    } catch (e) {
      toast.error(e.message || String(e))
    } finally {
      setMediaSavingId(null)
    }
  }

  const refreshVariants = async () => {
    if (!exerciseId) return
    const ex = await api.getExercise(exerciseId)
    setVariants((ex.variants || []).map(apiVariantToRow))
  }

  const updateVariantField = (id, patch) => {
    setFormDirty(true)
    setVariants((prev) => prev.map((v) => (v.id === id ? { ...v, ...patch } : v)))
  }

  const saveVariantRow = async (row) => {
    const payload = buildVariantPayloadFromRow(row)
    if (payload.variant_name.length < 3) {
      toast.error('Variantenname mindestens 3 Zeichen')
      return
    }
    setVariantSavingId(row.id)
    try {
      await api.updateExerciseVariant(exerciseId, row.id, payload)
      await refreshVariants()
    } catch (e) {
      toast.error(e.message || String(e))
    } finally {
      setVariantSavingId(null)
    }
  }

  const deleteVariantRow = async (id) => {
    if (!confirm('Variante wirklich löschen?')) return
    setVariantBusy(true)
    try {
      await api.deleteExerciseVariant(exerciseId, id)
      if (variantEditSelection === id) setVariantEditSelection(null)
      await refreshVariants()
    } catch (e) {
      toast.error(e.message || String(e))
    } finally {
      setVariantBusy(false)
    }
  }

  const moveVariantRow = async (idx, dir) => {
    const j = idx + dir
    if (j < 0 || j >= variants.length) return
    const next = [...variants]
    const tmp = next[idx]
    next[idx] = next[j]
    next[j] = tmp
    const ids = next.map((x) => x.id)
    setVariantBusy(true)
    try {
      await api.reorderExerciseVariants(exerciseId, ids)
      await refreshVariants()
    } catch (e) {
      toast.error(e.message || String(e))
    } finally {
      setVariantBusy(false)
    }
  }

  const createVariantSubmit = async (e) => {
    e.preventDefault()
    if (!exerciseId) return
    const payload = buildVariantPayloadFromRow(variantDraft)
    if (payload.variant_name.length < 3) {
      toast.error('Variantenname mindestens 3 Zeichen')
      return
    }
    setVariantBusy(true)
    try {
      const created = await api.createExerciseVariant(exerciseId, payload)
      setVariantDraft(emptyVariantDraft())
      await refreshVariants()
      if (created?.id != null) setVariantEditSelection(created.id)
      else setVariantEditSelection(null)
    } catch (err) {
      toast.error(err.message || String(err))
    } finally {
      setVariantBusy(false)
    }
  }

  const availableSkills = skillsCatalog.filter((s) => !formData.skills.some((x) => x.skill_id === s.id))

  const selectedVariantForEdit =
    typeof variantEditSelection === 'number' ? variants.find((v) => v.id === variantEditSelection) : null
  const selectedVariantIdx = selectedVariantForEdit
    ? variants.findIndex((v) => v.id === selectedVariantForEdit.id)
    : -1

  if (loading) {
    return (
      <div style={{ padding: '2rem', textAlign: 'center' }}>
        <div className="spinner"></div>
        <p>Laden...</p>
      </div>
    )
  }

  return (
    <div style={{ padding: '12px' }} className="app-page">
      <div style={{ marginBottom: '12px' }}>
        <button type="button" className="btn btn-secondary" onClick={() => navigate('/exercises')}>
          ← Übersicht
        </button>
        {isEdit && (
          <button
            type="button"
            className="btn btn-secondary"
            style={{ marginLeft: '8px' }}
            onClick={() => navigate(`/exercises/${exerciseId}`, { state: { fromExerciseEdit: true } })}
          >
            Ansehen
          </button>
        )}
      </div>

      <div className="card">
        <h1 style={{ marginTop: 0, fontSize: '1.25rem' }}>{isEdit ? 'Übung bearbeiten' : 'Neue Übung'}</h1>

        <form onSubmit={handleSubmit}>
          <div className="form-row">
            <label className="form-label">Titel *</label>
            <input
              type="text"
              className="form-input"
              value={formData.title}
              onChange={(e) => updateFormField('title', e.target.value)}
              required
              minLength={3}
            />
          </div>

          <div className="form-row">
            <label className="form-label">Kurzbeschreibung</label>
            <RichTextEditor
              value={formData.summary}
              onChange={(html) => updateFormField('summary', html)}
              placeholder="Kurzbeschreibung (optional)"
              minHeight="80px"
              inlineExerciseId={isEdit ? exerciseId : null}
              linkedExerciseMedia={isEdit ? mediaList : []}
              onExerciseMediaListChanged={refreshMedia}
            />
          </div>

          <div
            style={{
              padding: '12px',
              borderRadius: '8px',
              border: '1px solid var(--border)',
              background: 'var(--surface2)',
              marginBottom: '12px',
            }}
          >
            <h3 style={{ marginTop: 0, marginBottom: '10px', fontSize: '1rem' }}>Übungstyp</h3>
            <div className="form-row">
              <label className="form-label">Art</label>
              <select
                className="form-input"
                value={formData.exercise_kind === 'combination' ? 'combination' : 'simple'}
                onChange={(e) => {
                  const nk = e.target.value
                  setFormDirty(true)
                  setFormData((prev) => ({
                    ...prev,
                    exercise_kind: nk,
                    ...(nk === 'simple'
                      ? {
                          method_archetype: '',
                          method_profile_json: '{}',
                          combination_slots: [emptyComboSlotRow()],
                        }
                      : {}),
                  }))
                }}
              >
                <option value="simple">Einzelübung</option>
                <option value="combination">Kombinationsübung (Stationen / Pool)</option>
              </select>
            </div>
            {formData.exercise_kind === 'combination' ? (
              <>
                <div className="form-row">
                  <label className="form-label">Methoden-Archetyp (für Coach &amp; Planung empfohlen)</label>
                  <select
                    className="form-input"
                    value={formData.method_archetype || ''}
                    onChange={(e) => {
                      const arch = (e.target.value || '').trim()
                      const forced = ARCHETYPE_DEFAULT_REP_SERIES_COUNT[arch]
                      setFormDirty(true)
                      setFormData((prev) => {
                        const slots = prev.combination_slots || []
                        const nextSlots =
                          forced !== undefined && forced !== null
                            ? slots.map((row) =>
                                normalizeAdvanceMode(row.advance_mode) !== 'timed'
                                  ? {
                                      ...row,
                                      rep_series_count: String(Math.max(1, Math.round(Number(forced)))),
                                    }
                                  : row,
                              )
                            : slots
                        return { ...prev, method_archetype: arch, combination_slots: nextSlots }
                      })
                    }}
                  >
                    <option value="">— noch nicht festgelegt —</option>
                    {COMBINATION_ARCHETYPE_OPTIONS.map((o) => (
                      <option key={o.id} value={o.id}>
                        {o.label}
                      </option>
                    ))}
                  </select>
                </div>
                {String(formData.method_archetype || '').trim() === 'station_parcour' ? (
                  <p
                    style={{
                      fontSize: '12px',
                      color: 'var(--text2)',
                      margin: '4px 0 10px',
                      lineHeight: 1.48,
                      padding: '10px 12px',
                      borderRadius: '8px',
                      background: 'var(--surface)',
                      border: '1px solid var(--border)',
                    }}
                  >
                    <strong>Parcours / Bahnsystem:</strong> typischerweise starten alle an Station 1 und durchlaufen der
                    Reihe nach alle Punkte (Geschwindigkeit variabel). Die Stationsreihenfolge unten ist der Ablaufweg;
                    Zeitangaben pro Station und <strong>Gesamtdurchläufe</strong> im Ablaufprofil strukturieren das
                    spätere Coaching.
                  </p>
                ) : null}
                <div style={{ paddingTop: '4px', borderTop: '1px dashed var(--border)', marginBottom: '12px' }}>
                  <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'baseline', gap: '8px', flexWrap: 'wrap' }}>
                    <strong style={{ fontSize: '14px' }}>Stationen</strong>
                    <span style={{ fontSize: '11px', color: 'var(--text3)' }}>
                      Ablauf = Reihenfolge · ziehen / Pfeile · Einzelübungen · max. {MAX_COMBO_CANDIDATES_PER_STATION}/Station
                    </span>
                  </div>
                  <p style={{ fontSize: '12px', color: 'var(--text2)', margin: '6px 0 12px', lineHeight: 1.48 }}>
                    Pro Station oft <strong>eine</strong> feste Übung; höchstens <strong>drei</strong> als kleiner Auswahl‑Pool.
                    Unter <strong>Steuerung</strong> wählen: zeitlich, nach Wiederholungszahl oder ohne Arbeitsuhr (Coach führt).
                  </p>
                  {(formData.combination_slots || []).map((row, idx) => {
                    const candIds = Array.isArray(row.candidate_exercise_ids) ? row.candidate_exercise_ids : []
                    const comboPoolFull = candIds.length >= MAX_COMBO_CANDIDATES_PER_STATION
                    const slotAdv = normalizeAdvanceMode(row.advance_mode)
                    const serieLabel =
                      slotAdv === 'timed' ? 'Serie' : slotAdv === 'rep' ? 'Wdh. / Serie' : 'Richtwert'
                    const seriePlaceholder = slotAdv === 'rep' ? '10' : slotAdv === 'manual' ? '–' : '1'
                    const showMultiSeries = slotAdv === 'rep' || slotAdv === 'manual'
                    const serienCountUi = parseComboRepSeriesCountUi(row.rep_series_count)
                    const showInterSeriesPause = showMultiSeries && serienCountUi >= 2
                    const intraLabel = slotAdv === 'timed' ? 'Pause (s)' : 'Pause zw. Serien'
                    const lbl =
                      row.exercise_title_by_id && typeof row.exercise_title_by_id === 'object'
                        ? row.exercise_title_by_id
                        : {}
                    const isDropHere = comboDropTargetIx === idx
                    return (
                      <div
                        key={`combo-slot-${idx}`}
                        onDragOver={(e) => {
                          if (!e.dataTransfer?.types?.includes?.(DND_EXERCISE_COMBO_STATION)) return
                          e.preventDefault()
                          e.dataTransfer.dropEffect = 'move'
                          setComboDropTargetIx(idx)
                        }}
                        onDragLeave={() => setComboDropTargetIx((cur) => (cur === idx ? null : cur))}
                        onDrop={(e) => {
                          const rawFrom = e.dataTransfer.getData(DND_EXERCISE_COMBO_STATION)
                          const fromI = parseInt(rawFrom, 10)
                          e.preventDefault()
                          setComboDropTargetIx(null)
                          if (!Number.isFinite(fromI)) return
                          reorderCombinationSlots(fromI, idx)
                        }}
                        style={{
                          marginBottom: '12px',
                          padding: '12px 14px',
                          borderRadius: '12px',
                          border: `1px solid ${isDropHere ? 'var(--accent)' : 'var(--border)'}`,
                          background: 'var(--surface)',
                          boxShadow: isDropHere ? '0 0 0 2px var(--accent-soft)' : 'none',
                        }}
                      >
                        <div style={{ display: 'flex', flexWrap: 'wrap', gap: '10px', alignItems: 'flex-start', marginBottom: '12px' }}>
                          <button
                            type="button"
                            draggable
                            onDragStart={(e) => {
                              e.dataTransfer.effectAllowed = 'move'
                              e.dataTransfer.setData(DND_EXERCISE_COMBO_STATION, String(idx))
                            }}
                            onDragEnd={() => setComboDropTargetIx(null)}
                            aria-label={`Station ${idx + 1} ziehen`}
                            title="Ziehen zum Sortieren"
                            className="btn btn-secondary framework-ctrl framework-ctrl--xs"
                            style={{ cursor: 'grab', padding: '6px 8px', touchAction: 'none' }}
                          >
                            <GripVertical size={18} strokeWidth={2} aria-hidden />
                          </button>
                          <div style={{ display: 'flex', flexDirection: 'column', gap: '4px' }}>
                            <button
                              type="button"
                              className="btn btn-secondary framework-ctrl framework-ctrl--xs"
                              aria-label="Station nach oben"
                              disabled={idx === 0}
                              onClick={() => reorderCombinationSlots(idx, idx - 1)}
                            >
                              ▲
                            </button>
                            <button
                              type="button"
                              className="btn btn-secondary framework-ctrl framework-ctrl--xs"
                              aria-label="Station nach unten"
                              disabled={idx === (formData.combination_slots || []).length - 1}
                              onClick={() => reorderCombinationSlots(idx, idx + 2)}
                            >
                              ▼
                            </button>
                          </div>
                          <div className="form-row" style={{ flex: '1 1 200px', marginBottom: 0 }}>
                            <label className="form-label" style={{ fontSize: '12px' }}>
                              Name (St.&nbsp;{idx + 1})
                            </label>
                            <input
                              type="text"
                              className="form-input"
                              value={row.title || ''}
                              placeholder="z.&nbsp;B. Liegestütz"
                              onChange={(e) => patchComboSlotRow(idx, { title: e.target.value })}
                            />
                          </div>
                          <div style={{ display: 'flex', flexWrap: 'wrap', gap: '8px', alignItems: 'flex-end' }}>
                            <button
                              type="button"
                              className="btn btn-secondary framework-ctrl framework-ctrl--xs"
                              disabled={comboPoolFull}
                              title={
                                comboPoolFull
                                  ? `Max. ${MAX_COMBO_CANDIDATES_PER_STATION} Übungen — eine entfernen, um weitere zu wählen.`
                                  : 'Einzelübung zur Station hinzufügen'
                              }
                              onClick={() => setComboStationPickerIx(idx)}
                            >
                              + Übung
                            </button>
                            <button
                              type="button"
                              className="btn framework-ctrl framework-ctrl--xs"
                              style={{ fontSize: '12px' }}
                              title="Diese Station entfernen"
                              onClick={() => {
                                const prev = formData.combination_slots || []
                                const next = prev.filter((_, j) => j !== idx)
                                updateFormField('combination_slots', next.length ? next : [emptyComboSlotRow()])
                              }}
                            >
                              Entfernen
                            </button>
                          </div>
                        </div>
                        <div style={{ marginBottom: '12px' }}>
                          <span className="form-label" style={{ fontSize: '11px', display: 'block', marginBottom: '6px' }}>
                            Übungen ({candIds.length}/{MAX_COMBO_CANDIDATES_PER_STATION})
                          </span>
                          {candIds.length === 0 ? (
                            <p style={{ fontSize: '12px', color: 'var(--text3)', margin: 0 }}>
                              Mindestens eine Übung — mit „+ Übung“ wählen.
                            </p>
                          ) : (
                            <ul style={{ listStyle: 'none', padding: 0, margin: 0, display: 'flex', flexWrap: 'wrap', gap: '6px' }}>
                              {candIds.map((id) => (
                                <li
                                  key={`${idx}-c-${id}`}
                                  style={{
                                    display: 'inline-flex',
                                    alignItems: 'center',
                                    gap: '6px',
                                    padding: '4px 10px',
                                    borderRadius: '999px',
                                    border: '1px solid var(--border)',
                                    background: 'var(--surface2)',
                                    fontSize: '12px',
                                  }}
                                >
                                  <span style={{ overflow: 'hidden', textOverflow: 'ellipsis', maxWidth: '14rem' }} title={`#${id}`}>
                                    {(lbl[id] || lbl[String(id)] || '').trim() || `Übung #${id}`}
                                  </span>
                                  <button
                                    type="button"
                                    className="tu-icon-btn"
                                    aria-label={`Übung ${id} entfernen`}
                                    title="Entfernen"
                                    onClick={() => removeCandidateFromSlot(idx, id)}
                                  >
                                    ✗
                                  </button>
                                </li>
                              ))}
                            </ul>
                          )}
                        </div>
                        <div className="form-row" style={{ marginBottom: '8px', maxWidth: '22rem' }}>
                          <label className="form-label" style={{ fontSize: '11px' }}>
                            Steuerung
                          </label>
                          <select
                            className="form-input"
                            style={{ fontSize: '0.8125rem' }}
                            value={slotAdv}
                            onChange={(e) => {
                              const m = normalizeAdvanceMode(e.target.value)
                              const patch = { advance_mode: m }
                              if (m !== 'timed') patch.load_sec = ''
                              if (m === 'rep' || m === 'manual') {
                                const curSer = String(row.rep_series_count ?? '').trim()
                                if (!curSer) {
                                  patch.rep_series_count = String(
                                    defaultRepSeriesCountForArchetype(formData.method_archetype || ''),
                                  )
                                }
                              }
                              patchComboSlotRow(idx, patch)
                            }}
                          >
                            <option value="timed">Zeit (Arbeit in Sekunden)</option>
                            <option value="rep">Wiederholungen (Ziel)</option>
                            <option value="manual">Coach (Weiter nach Freigabe)</option>
                          </select>
                        </div>
                        <p style={{ fontSize: '11px', color: 'var(--text3)', margin: '0 0 10px', lineHeight: 1.42 }}>
                          {slotAdv === 'timed'
                            ? 'Arbeit (s): geplantes Ende nach Countdown möglich. Serie: Wiederholungen ohne Stationswechsel innerhalb einer Phase.'
                            : slotAdv === 'rep'
                              ? 'Ohne Pflicht-Arbeits-Timer: Ziel über Wiederholungen. Ab zwei Serien: Pause zwischen diesen Serien; sonst nur Wechsel zur nächsten Station.'
                              : 'Coach: keine feste Arbeitsuhr — Fortschritt später per Tipp. Ab 2 Serien: Pause zwischen Serien; sonst nur Wechsel zur nächsten Station zeitlich planen.'}
                        </p>
                        <div
                          style={{
                            display: 'grid',
                            gridTemplateColumns: 'repeat(auto-fill, minmax(5.25rem, 1fr))',
                            gap: '8px 10px',
                            alignItems: 'end',
                          }}
                        >
                          {slotAdv === 'timed' ? (
                            <div className="form-row" style={{ marginBottom: 0 }}>
                              <label className="form-label" style={{ fontSize: '10px' }}>
                                Arbeit (s)
                              </label>
                              <input
                                type="number"
                                min={0}
                                className="form-input"
                                style={comboTinyNumberInputSx}
                                placeholder="–"
                                value={row.load_sec || ''}
                                onChange={(e) => patchComboSlotRow(idx, { load_sec: e.target.value })}
                              />
                            </div>
                          ) : null}
                          <div className="form-row" style={{ marginBottom: 0 }}>
                            <label className="form-label" style={{ fontSize: '10px' }}>
                              {serieLabel}
                            </label>
                            <input
                              type="number"
                              min={slotAdv === 'rep' ? 1 : undefined}
                              className="form-input"
                              style={comboTinyNumberInputSx}
                              placeholder={seriePlaceholder}
                              value={row.consecutive_reps || ''}
                              onChange={(e) => patchComboSlotRow(idx, { consecutive_reps: e.target.value })}
                            />
                          </div>
                          {showMultiSeries ? (
                            <div className="form-row" style={{ marginBottom: 0 }}>
                              <label className="form-label" style={{ fontSize: '10px' }} title="Wie oft die angegebene Wdh.-Zahl hintereinander (mit Pause zw. Serien)?">
                                Serien
                              </label>
                              <input
                                type="number"
                                min={slotAdv === 'rep' ? 1 : undefined}
                                className="form-input"
                                style={comboTinyNumberInputSx}
                                placeholder="1"
                                value={row.rep_series_count || ''}
                                onChange={(e) => {
                                  let rawSer = e.target.value.trim()
                                  if (rawSer === '') rawSer = '1'
                                  const pn = parseInt(String(rawSer).trim(), 10)
                                  const patch = { rep_series_count: rawSer }
                                  if (!Number.isFinite(pn) || pn < 2) patch.intra_rep_rest_sec = ''
                                  patchComboSlotRow(idx, patch)
                                }}
                              />
                            </div>
                          ) : null}
                          {slotAdv === 'timed' || showInterSeriesPause ? (
                            <div className="form-row" style={{ marginBottom: 0 }}>
                              <label className="form-label" style={{ fontSize: '10px' }}>
                                {intraLabel}
                              </label>
                              <input
                                type="number"
                                min={0}
                                className="form-input"
                                style={comboTinyNumberInputSx}
                                placeholder="–"
                                value={row.intra_rep_rest_sec || ''}
                                onChange={(e) => patchComboSlotRow(idx, { intra_rep_rest_sec: e.target.value })}
                              />
                            </div>
                          ) : null}
                          <div className="form-row" style={{ marginBottom: 0 }}>
                            <label className="form-label" style={{ fontSize: '10px' }}>
                              Wechsel (s)
                            </label>
                            <input
                              type="number"
                              min={0}
                              className="form-input"
                              style={comboTinyNumberInputSx}
                              placeholder="–"
                              value={row.transition_after_sec || ''}
                              onChange={(e) => patchComboSlotRow(idx, { transition_after_sec: e.target.value })}
                            />
                          </div>
                        </div>
                        {showMultiSeries && serienCountUi < 2 ? (
                          <p style={{ fontSize: '10px', color: 'var(--text3)', margin: '6px 0 0', lineHeight: 1.38 }}>
                            <strong>Wechsel (s)</strong> = Pause bis zur <strong>nächsten Station</strong>. Feld „Pause zw.
                            Serien“ erscheint erst ab&nbsp;2 Serien (sonst keine Pause zwischen zwei Blöcken nötig).
                          </p>
                        ) : null}
                      </div>
                    )
                  })}
                  <div
                    onDragOver={(e) => {
                      if (!e.dataTransfer?.types?.includes?.(DND_EXERCISE_COMBO_STATION)) return
                      e.preventDefault()
                      e.dataTransfer.dropEffect = 'move'
                    }}
                    onDrop={(e) => {
                      const rawFrom = e.dataTransfer.getData(DND_EXERCISE_COMBO_STATION)
                      const fromI = parseInt(rawFrom, 10)
                      e.preventDefault()
                      setComboDropTargetIx(null)
                      if (!Number.isFinite(fromI)) return
                      const len = (formData.combination_slots || []).length
                      reorderCombinationSlots(fromI, len)
                    }}
                    style={{
                      padding: '10px',
                      textAlign: 'center',
                      fontSize: '11px',
                      color: 'var(--text3)',
                      border: '1px dashed var(--border)',
                      borderRadius: '10px',
                      marginBottom: '8px',
                    }}
                  >
                    Hier ablegen zum Anhängen am Ende der Reihenfolge
                  </div>
                  <button
                    type="button"
                    className="btn btn-secondary"
                    style={{ fontSize: '12px', marginTop: '4px' }}
                    onClick={() => updateFormField('combination_slots', [...(formData.combination_slots || []), emptyComboSlotRow()])}
                  >
                    + Station
                  </button>
                </div>
                <div className="form-row">
                  <label className="form-label">Ablaufprofil (Runden &amp; global)</label>
                  <CombinationMethodProfileEditor
                    methodArchetype={formData.method_archetype || ''}
                    methodProfileJson={formData.method_profile_json || '{}'}
                    onChangeMethodProfileJson={(s) => updateFormField('method_profile_json', s)}
                    comboSlotsOutline={(formData.combination_slots || []).map((r, i) => ({
                      slot_index: i,
                      title: r.title || '',
                    }))}
                    omitPerSlotTiming
                  />
                </div>
              </>
            ) : null}
          </div>

          <div className="form-row">
            <label className="form-label">Ziel *</label>
            <RichTextEditor
              value={formData.goal}
              onChange={(html) => updateFormField('goal', html)}
              placeholder="Trainingsziel"
              minHeight="120px"
              inlineExerciseId={isEdit ? exerciseId : null}
              linkedExerciseMedia={isEdit ? mediaList : []}
              onExerciseMediaListChanged={refreshMedia}
            />
          </div>

          <div className="form-row">
            <label className="form-label">Durchführung *</label>
            <RichTextEditor
              value={formData.execution}
              onChange={(html) => updateFormField('execution', html)}
              placeholder="Ablauf Schritt für Schritt"
              minHeight="180px"
              inlineExerciseId={isEdit ? exerciseId : null}
              linkedExerciseMedia={isEdit ? mediaList : []}
              onExerciseMediaListChanged={refreshMedia}
            />
          </div>

          <div className="form-row">
            <label className="form-label">Vorbereitung / Aufbau</label>
            <RichTextEditor
              value={formData.preparation}
              onChange={(html) => updateFormField('preparation', html)}
              placeholder="Matten, Raum, …"
              minHeight="100px"
              inlineExerciseId={isEdit ? exerciseId : null}
              linkedExerciseMedia={isEdit ? mediaList : []}
              onExerciseMediaListChanged={refreshMedia}
            />
          </div>

          <div className="form-row">
            <label className="form-label">Hinweise für Trainer</label>
            <RichTextEditor
              value={formData.trainer_notes}
              onChange={(html) => updateFormField('trainer_notes', html)}
              placeholder="Sicherheit, Varianten-Hinweise, …"
              minHeight="100px"
              inlineExerciseId={isEdit ? exerciseId : null}
              linkedExerciseMedia={isEdit ? mediaList : []}
              onExerciseMediaListChanged={refreshMedia}
            />
          </div>

          <div className="form-row">
            <label className="form-label">Material (eine Zeile oder kommagetrennt)</label>
            <textarea
              className="form-input"
              rows={3}
              value={formData.equipmentLines}
              onChange={(e) => updateFormField('equipmentLines', e.target.value)}
              placeholder="Matten&#10;Pratzen"
            />
          </div>

          <div style={{ display: 'grid', gridTemplateColumns: '1fr 1fr', gap: '10px' }}>
            <div className="form-row">
              <label className="form-label">Dauer Min</label>
              <input
                type="number"
                className="form-input"
                value={formData.duration_min}
                onChange={(e) =>
                  updateFormField('duration_min', e.target.value ? parseInt(e.target.value, 10) : '')
                }
              />
            </div>
            <div className="form-row">
              <label className="form-label">Dauer Max</label>
              <input
                type="number"
                className="form-input"
                value={formData.duration_max}
                onChange={(e) =>
                  updateFormField('duration_max', e.target.value ? parseInt(e.target.value, 10) : '')
                }
              />
            </div>
          </div>

          <div style={{ display: 'grid', gridTemplateColumns: '1fr 1fr', gap: '10px' }}>
            <div className="form-row">
              <label className="form-label">Gruppe Min</label>
              <input
                type="number"
                className="form-input"
                value={formData.group_size_min}
                onChange={(e) =>
                  updateFormField('group_size_min', e.target.value ? parseInt(e.target.value, 10) : '')
                }
              />
            </div>
            <div className="form-row">
              <label className="form-label">Gruppe Max</label>
              <input
                type="number"
                className="form-input"
                value={formData.group_size_max}
                onChange={(e) =>
                  updateFormField('group_size_max', e.target.value ? parseInt(e.target.value, 10) : '')
                }
              />
            </div>
          </div>

          <MultiAssocBlock
            title="Fokusbereiche (0…n, ein „primär“)"
            rows={formData.focus_areas_multi}
            setRows={(r) => updateFormField('focus_areas_multi', r)}
            options={focusAreas}
            idKey="focus_area_id"
            emptyLabel="Keine Zuordnung — optional „+ Eintrag“."
          />

          <MultiAssocBlock
            title="Stilrichtungen (0…n, z. B. Shotokan)"
            rows={formData.training_styles_multi}
            setRows={(r) => updateFormField('training_styles_multi', r)}
            options={styleDirections.map((sd) => ({
              ...sd,
              name: sd.parent_style_name ? `${sd.name} (${sd.parent_style_name})` : sd.name,
            }))}
            idKey="training_style_id"
            emptyLabel="Keine Stilrichtung gewählt."
          />

          <MultiAssocBlock
            title="Trainingsstil (0…n, z. B. Breitensport / Leistungssport)"
            rows={formData.training_types_multi}
            setRows={(r) => updateFormField('training_types_multi', r)}
            options={trainingTypes}
            idKey="training_type_id"
            emptyLabel="Kein Trainingsstil gewählt."
          />

          <MultiAssocBlock
            title="Zielgruppen (0…n)"
            rows={formData.target_groups_multi}
            setRows={(r) => updateFormField('target_groups_multi', r)}
            options={targetGroups}
            idKey="target_group_id"
            emptyLabel="Keine Zielgruppe gewählt."
          />

          <div className="form-row">
            <label className="form-label">Fähigkeiten (je Übung mehrere, mit Niveau)</label>
            <div style={{ display: 'flex', flexWrap: 'wrap', gap: '8px', marginBottom: '10px' }}>
              <select
                className="form-input"
                style={{ flex: '1 1 200px' }}
                value={skillPick}
                onChange={(e) => setSkillPick(e.target.value)}
              >
                <option value="">Fähigkeit wählen…</option>
                {availableSkills.map((s) => (
                  <option key={s.id} value={s.id}>
                    {s.name} ({s.category})
                  </option>
                ))}
              </select>
              <button type="button" className="btn btn-secondary" onClick={addSkillRow}>
                Hinzufügen
              </button>
            </div>
            {formData.skills.map((row, idx) => {
              const sk = skillsCatalog.find((s) => s.id === row.skill_id)
              return (
                <div key={`${row.skill_id}-${idx}`} className="skills-editor-row">
                  <div>
                    <strong style={{ fontSize: '14px' }}>{sk?.name || `Skill #${row.skill_id}`}</strong>
                    {sk?.category && (
                      <span style={{ color: 'var(--text2)', fontSize: '12px', marginLeft: '6px' }}>
                        {sk.category}
                      </span>
                    )}
                  </div>
                  <label style={{ fontSize: '12px', display: 'flex', alignItems: 'center', gap: '4px' }}>
                    <input
                      type="radio"
                      name="skill-primary"
                      checked={row.is_primary}
                      onChange={() => setSkillPrimary(idx)}
                    />
                    primär
                  </label>
                  <select
                    className="form-input"
                    value={row.intensity || ''}
                    onChange={(e) => updateSkillField(idx, 'intensity', e.target.value)}
                  >
                    {INTENSITY_OPTIONS.map((o) => (
                      <option key={o.value || 'i'} value={o.value}>
                        {o.label}
                      </option>
                    ))}
                  </select>
                  <select
                    className="form-input"
                    value={row.required_level || ''}
                    onChange={(e) => updateSkillField(idx, 'required_level', e.target.value)}
                  >
                    {SKILL_LEVEL_OPTIONS.map((o) => (
                      <option key={`r-${o.value}`} value={o.value}>
                        von {o.label}
                      </option>
                    ))}
                  </select>
                  <select
                    className="form-input"
                    value={row.target_level || ''}
                    onChange={(e) => updateSkillField(idx, 'target_level', e.target.value)}
                  >
                    {SKILL_LEVEL_OPTIONS.map((o) => (
                      <option key={`t-${o.value}`} value={o.value}>
                        bis {o.label}
                      </option>
                    ))}
                  </select>
                  <button type="button" className="btn" style={{ fontSize: '12px', padding: '4px 8px' }} onClick={() => removeSkillRow(idx)}>
                    Entf.
                  </button>
                </div>
              )
            })}
          </div>

          <div style={{ display: 'grid', gridTemplateColumns: '1fr 1fr', gap: '10px' }}>
            <div className="form-row">
              <label className="form-label">Sichtbarkeit</label>
              <select
                className="form-input"
                value={formData.visibility}
                onChange={(e) => updateFormField('visibility', e.target.value)}
              >
                <option value="private">Privat</option>
                <option value="club">Verein</option>
                {isSuperadmin ? <option value="official">Offiziell</option> : null}
              </select>
            </div>
            <div className="form-row">
              <label className="form-label">Status</label>
              <select
                className="form-input"
                value={formData.status}
                onChange={(e) => updateFormField('status', e.target.value)}
              >
                <option value="draft">Entwurf</option>
                <option value="in_review">In Prüfung</option>
                <option value="approved">Freigegeben</option>
                <option value="archived">Archiviert</option>
              </select>
            </div>
          </div>

          {formData.visibility === 'club' && visibilityClubChoices.length > 0 ? (
            <div className="form-row" style={{ marginTop: '10px' }}>
              <label className="form-label">Verein (Sichtbarkeit)</label>
              <select
                className="form-input"
                value={formData.club_id != null && formData.club_id !== '' ? String(formData.club_id) : ''}
                onChange={(e) => {
                  const v = e.target.value
                  updateFormField('club_id', v === '' ? null : Number(v))
                }}
              >
                {visibilityClubChoices.map((c) => (
                  <option key={c.id} value={String(c.id)}>
                    {(c.name || '').trim() || `Verein #${c.id}`}
                  </option>
                ))}
              </select>
              <p style={{ margin: '6px 0 0', fontSize: '12px', color: 'var(--text3)', lineHeight: 1.4 }}>
                Standard ist der aktive Verein aus der Navigation. Bei Plattform-Admins sind alle Vereine wählbar.
              </p>
            </div>
          ) : null}

          <div style={{ marginTop: '16px' }}>
            <button type="submit" className="btn btn-primary" disabled={saving}>
              {saving ? 'Speichern…' : isEdit ? 'Speichern' : 'Anlegen & weiter'}
            </button>
          </div>
        </form>
      </div>

      {isEdit && formData.exercise_kind !== 'combination' && (
        <details ref={variantsDetailsRef} className="card exercise-variants-details" style={{ marginTop: '16px' }}>
          <summary className="exercise-variants-summary">
            <span className="exercise-variants-summary__title">Übungsvarianten</span>
            <span className="exercise-variants-summary__badge">
              {variants.length === 0
                ? 'keine'
                : `${variants.length} ${variants.length === 1 ? 'Variante' : 'Varianten'}`}
            </span>
          </summary>
          <div className="exercise-variants-details__body">
            <p className="exercise-variants-hint">
              Pro Durchgang nur eine Variante bearbeiten – weniger Scrollen. Reihenfolge entspricht Planung und Auswahl im
              Training; „Voraussetzung“ nutzt ihr später für Progressions-Serien.
            </p>

            {variants.length > 0 && (
              <div className="form-row">
                <label className="form-label" htmlFor="variant-edit-select">
                  Variante auswählen
                </label>
                <select
                  id="variant-edit-select"
                  className="form-input"
                  value={
                    variantEditSelection === 'new'
                      ? 'new'
                      : variantEditSelection == null
                        ? ''
                        : String(variantEditSelection)
                  }
                  onChange={(e) => {
                    const val = e.target.value
                    if (val === '') setVariantEditSelection(null)
                    else if (val === 'new') setVariantEditSelection('new')
                    else setVariantEditSelection(parseInt(val, 10))
                  }}
                >
                  <option value="">— nicht bearbeiten —</option>
                  {variants.map((v) => (
                    <option key={v.id} value={v.id}>
                      {(v.variant_name && String(v.variant_name).trim()) || `Variante #${v.id}`}
                    </option>
                  ))}
                  <option value="new">+ Neue Variante anlegen…</option>
                </select>
              </div>
            )}

            {variants.length === 0 && (
              <p style={{ fontSize: '13px', color: 'var(--text3)', marginBottom: '10px' }}>
                Noch keine Varianten – optional für andere Ausführung, Dauer oder Material in Planung und Training.
              </p>
            )}

            {variants.length === 0 && variantEditSelection !== 'new' && (
              <button type="button" className="btn btn-secondary" onClick={() => setVariantEditSelection('new')}>
                Erste Variante anlegen
              </button>
            )}

            {variantEditSelection === 'new' && (
              <form
                className="exercise-variant-single-form"
                onSubmit={createVariantSubmit}
                style={{ marginTop: '14px', paddingTop: '14px', borderTop: '1px solid var(--border)' }}
              >
                <h3 style={{ marginTop: 0, fontSize: '1rem' }}>Neue Variante</h3>
                <ExerciseVariantFields
                  row={variantDraft}
                  onPatch={(patch) => {
                    setFormDirty(true)
                    setVariantDraft((d) => ({ ...d, ...patch }))
                  }}
                  prerequisiteOthers={variants}
                  rteMinHeight="110px"
                  inlineExerciseId={isEdit ? exerciseId : null}
                  linkedExerciseMedia={isEdit ? mediaList : []}
                  onExerciseMediaListChanged={refreshMedia}
                />
                <button type="submit" className="btn btn-primary" style={{ marginTop: '10px' }} disabled={variantBusy}>
                  {variantBusy ? 'Anlegen…' : 'Variante anlegen'}
                </button>
              </form>
            )}

            {selectedVariantForEdit && (
              <div
                className="exercise-variant-single-form"
                style={{ marginTop: '14px', paddingTop: '14px', borderTop: '1px solid var(--border)' }}
              >
                <div
                  style={{
                    display: 'flex',
                    flexWrap: 'wrap',
                    gap: '8px',
                    alignItems: 'center',
                    marginBottom: '12px',
                  }}
                >
                  <span style={{ fontSize: '12px', color: 'var(--text3)' }}>
                    Pos. {selectedVariantIdx + 1} von {variants.length}
                  </span>
                  <button
                    type="button"
                    className="btn btn-secondary"
                    style={{ fontSize: '11px', padding: '4px 8px' }}
                    disabled={variantBusy || selectedVariantIdx <= 0}
                    onClick={() => moveVariantRow(selectedVariantIdx, -1)}
                  >
                    Nach oben
                  </button>
                  <button
                    type="button"
                    className="btn btn-secondary"
                    style={{ fontSize: '11px', padding: '4px 8px' }}
                    disabled={variantBusy || selectedVariantIdx >= variants.length - 1}
                    onClick={() => moveVariantRow(selectedVariantIdx, 1)}
                  >
                    Nach unten
                  </button>
                  <button
                    type="button"
                    className="btn btn-primary"
                    style={{ marginLeft: 'auto', fontSize: '12px' }}
                    disabled={variantSavingId === selectedVariantForEdit.id || variantBusy}
                    onClick={() => saveVariantRow(selectedVariantForEdit)}
                  >
                    {variantSavingId === selectedVariantForEdit.id ? 'Speichern…' : 'Speichern'}
                  </button>
                  <button
                    type="button"
                    className="btn"
                    style={{ fontSize: '12px', background: 'var(--danger)', color: '#fff', border: 'none' }}
                    disabled={variantBusy}
                    onClick={() => deleteVariantRow(selectedVariantForEdit.id)}
                  >
                    Löschen
                  </button>
                </div>
                <ExerciseVariantFields
                  row={selectedVariantForEdit}
                  onPatch={(patch) => updateVariantField(selectedVariantForEdit.id, patch)}
                  prerequisiteOthers={variants.filter((o) => o.id !== selectedVariantForEdit.id)}
                  rteMinHeight="110px"
                  inlineExerciseId={isEdit ? exerciseId : null}
                  linkedExerciseMedia={isEdit ? mediaList : []}
                  onExerciseMediaListChanged={refreshMedia}
                />
              </div>
            )}

            {variants.length > 0 && variantEditSelection == null && (
              <p style={{ fontSize: '13px', color: 'var(--text3)', marginTop: '12px', marginBottom: 0 }}>
                Wähle eine Variante zum Bearbeiten oder „Neue Variante anlegen…“.
              </p>
            )}
          </div>
        </details>
      )}

      {isEdit && formData.exercise_kind !== 'combination' && (
        <details className="card exercise-variants-details" style={{ marginTop: '16px' }}>
          <summary className="exercise-variants-summary">
            <span className="exercise-variants-summary__title">Progressionsgraph</span>
            <span className="exercise-variants-summary__badge">Übung → Übung</span>
          </summary>
          <div className="exercise-variants-details__body">
            <ExerciseProgressionGraphPanel anchorExerciseId={exerciseId} anchorTitle={formData.title} />
          </div>
        </details>
      )}

      {isEdit && (
        <div className="card" style={{ marginTop: '16px' }}>
          <h2 style={{ marginTop: 0, fontSize: '1.1rem' }}>Medien</h2>
          <p style={{ color: 'var(--text2)', fontSize: '13px', marginBottom: '6px' }}>
            Neue Uploads oder Embeds über die Textfeld-Symbolleiste („Medien im Text“ / „Embed im Text“). Hier
            verwaltest du Verknüpfungen — Kachel in ein Textfeld ziehen, um sie an der Cursorposition einzufügen
            (mittlere Darstellung).
          </p>
          <p style={{ color: 'var(--text3)', fontSize: '12px', marginTop: 0 }}>
            Max. 10 Medien pro Übung.
          </p>
          <div
            style={{
              display: 'flex',
              flexWrap: 'wrap',
              gap: '8px',
              alignItems: 'center',
              marginTop: '10px',
            }}
          >
            <button type="button" className="btn btn-secondary" onClick={() => setArchiveOpen(true)}>
              Aus Archiv verknüpfen…
            </button>
            <Link to="/media" className="btn btn-secondary" style={{ textDecoration: 'none' }}>
              Medienbibliothek
            </Link>
          </div>
          {mediaList.length > 0 && (
            <ul className="exercise-edit-media-strip">
              {mediaList.map((m, idx) => {
                const cap =
                  (m.title || '').trim() ||
                  (m.original_filename || '').trim() ||
                  (m.embed_url ? String(m.embed_url).replace(/^https?:\/\//i, '').slice(0, 80) : '')
                const sub = [m.media_type, m.embed_platform].filter(Boolean).join(' · ') || 'Medium'
                const payloadCaption = (
                  [m.title, m.original_filename].find((x) => typeof x === 'string' && x.trim()) || ''
                ).trim()
                return (
                  <li key={m.id} className="exercise-edit-media-strip__item">
                    <div className="exercise-edit-media-strip__lead">
                      {!m.embed_url ? (
                        <ExerciseMediaThumbTile exerciseId={exerciseId} media={m} onOpenPreview={setMediaPreview} size={76} />
                      ) : (
                        <div
                          className="exercise-edit-media-strip__embed-badge exercise-edit-media-strip__embed-badge--solo"
                          aria-hidden
                        >
                          {m.embed_platform || 'Embed'}
                        </div>
                      )}
                      <div
                        className="exercise-edit-media-strip__handle"
                        title="Mit Drag und Drop in ein Textfeld ziehen"
                        draggable
                        onDragStart={(e) => {
                          try {
                            e.dataTransfer.setData(
                              SHINKAN_EXERCISE_MEDIA_DRAG_MIME,
                              buildExerciseMediaDragPayload(m.id, payloadCaption),
                            )
                            e.dataTransfer.effectAllowed = 'copy'
                          } catch (_) {
                            /* ignore */
                          }
                        }}
                      >
                        ⣿<span className="exercise-edit-media-strip__handle-text"> Ziehen</span>
                      </div>
                    </div>
                    <div className="exercise-edit-media-strip__body">
                      <div className="exercise-edit-media-strip__headline">
                        <span style={{ fontSize: '12px', color: 'var(--text3)' }}>
                          #{m.id} · {sub}
                        </span>
                      </div>
                      <div style={{ fontSize: '13px', color: 'var(--text2)', lineHeight: 1.35 }}>{cap || '—'}</div>
                      <div className="exercise-edit-media-strip__toolbar">
                        <input
                          type="text"
                          className="form-input exercise-edit-media-strip__title"
                          placeholder="Titel (wird in der Vorschau und im Platzhalter genutzt)"
                          value={(mediaFields[m.id] || {}).title ?? ''}
                          onChange={(e) =>
                            setMediaFields((prev) => ({
                              ...prev,
                              [m.id]: {
                                title: e.target.value,
                              },
                            }))
                          }
                        />
                      </div>
                      <div className="exercise-edit-media-strip__actions">
                        {mediaList.length > 1 && (
                          <>
                            <button
                              type="button"
                              className="btn btn-secondary"
                              style={{ fontSize: '11px', padding: '4px 8px' }}
                              disabled={idx === 0}
                              onClick={() => moveMediaRow(idx, -1)}
                              title="Nach oben"
                            >
                              ↑
                            </button>
                            <button
                              type="button"
                              className="btn btn-secondary"
                              style={{ fontSize: '11px', padding: '4px 8px' }}
                              disabled={idx >= mediaList.length - 1}
                              onClick={() => moveMediaRow(idx, 1)}
                              title="Nach unten"
                            >
                              ↓
                            </button>
                          </>
                        )}
                        <button
                          type="button"
                          className="btn btn-primary"
                          style={{ fontSize: '12px', padding: '4px 10px' }}
                          disabled={mediaSavingId === m.id}
                          onClick={() => saveMediaMeta(m.id)}
                        >
                          {mediaSavingId === m.id ? '…' : 'Speichern'}
                        </button>
                        <button
                          type="button"
                          className="btn btn-secondary"
                          style={{ fontSize: '12px', padding: '4px 10px' }}
                          onClick={() => handleDeleteMedia(m.id)}
                        >
                          Entfernen
                        </button>
                      </div>
                    </div>
                  </li>
                )
              })}
            </ul>
          )}
          <p style={{ color: 'var(--text3)', fontSize: '12px', marginTop: mediaList.length ? '12px' : 0 }}>
            Verknüpfungen bleiben nötig (u. a. Zugriff, Orphan-Hinweise): Im Fließtext verweist du gezielt über
            Platzhalter. Ohne Verknüpfung gäbe es keine exercise_media-ID zum Einbetten.
          </p>
          {archiveOpen && (
            <div
              role="dialog"
              aria-modal="true"
              aria-label="Medienarchiv"
              style={{
                position: 'fixed',
                inset: 0,
                background: 'rgba(0,0,0,0.5)',
                zIndex: 1000,
                overflow: 'auto',
                padding: '16px',
              }}
              onClick={() => setArchiveOpen(false)}
              onKeyDown={(e) => e.key === 'Escape' && setArchiveOpen(false)}
            >
              <div
                className="card"
                style={{
                  maxWidth: 560,
                  margin: '4vh auto',
                  maxHeight: '88vh',
                  overflow: 'auto',
                  position: 'relative',
                }}
                onClick={(e) => e.stopPropagation()}
              >
                <h3 style={{ marginTop: 0, fontSize: '1.05rem' }}>Medienarchiv</h3>
                <input
                  type="search"
                  className="form-input"
                  placeholder="Suche Dateiname…"
                  value={archiveQ}
                  onChange={(e) => setArchiveQ(e.target.value)}
                  style={{ marginBottom: '8px' }}
                />
                {archiveLoading && <p style={{ fontSize: '13px', color: 'var(--text3)' }}>Laden…</p>}
                {archiveError && <p style={{ fontSize: '13px', color: 'var(--danger)' }}>{archiveError}</p>}
                {!archiveLoading && !archiveError && archiveItems.length === 0 && (
                  <p style={{ fontSize: '13px', color: 'var(--text3)' }}>Keine Treffer.</p>
                )}
                <ul style={{ listStyle: 'none', padding: 0, margin: 0 }}>
                  {archiveItems.map((a) => {
                    const already = linkedArchiveAssetIds.has(a.id)
                    return (
                    <li
                      key={a.id}
                      style={{
                        display: 'flex',
                        gap: '10px',
                        alignItems: 'center',
                        padding: '8px 0',
                        borderBottom: '1px solid var(--border)',
                      }}
                    >
                      <div
                        style={{
                          width: 56,
                          height: 56,
                          flexShrink: 0,
                          borderRadius: '6px',
                          overflow: 'hidden',
                          background: 'var(--surface2, rgba(127,127,127,0.12))',
                          border: '1px solid var(--border)',
                          display: 'flex',
                          alignItems: 'center',
                          justifyContent: 'center',
                        }}
                      >
                        {a.mime_type?.startsWith('image/') ? (
                          <img
                            alt=""
                            src={resolveMediaAssetFileUrl(a.id)}
                            style={{ width: '100%', height: '100%', objectFit: 'cover' }}
                          />
                        ) : a.mime_type?.startsWith('video/') ? (
                          <span style={{ fontSize: '18px', opacity: 0.75 }} aria-hidden>
                            ▶
                          </span>
                        ) : (
                          <span style={{ fontSize: '10px', color: 'var(--text2)', padding: '2px', textAlign: 'center' }}>
                            PDF
                          </span>
                        )}
                      </div>
                      <div style={{ flex: 1, minWidth: 0 }}>
                        <div style={{ fontSize: '13px', fontWeight: 600, wordBreak: 'break-word' }}>
                          {a.original_filename || `Asset #${a.id}`}
                        </div>
                        <div style={{ fontSize: '11px', color: 'var(--text3)', marginTop: '2px' }}>
                          {a.visibility} · {a.mime_type || '—'}{' '}
                          {a.byte_size != null ? `· ${(a.byte_size / 1024).toFixed(0)} KB` : ''}
                        </div>
                      </div>
                      <button
                        type="button"
                        className="btn btn-primary"
                        style={{ fontSize: '12px' }}
                        disabled={already}
                        title={already ? 'Schon mit dieser Übung verknüpft' : ''}
                        onClick={() => !already && attachFromArchive(a.id)}
                      >
                        {already ? 'Bereits verknüpft' : 'Verknüpfen'}
                      </button>
                    </li>
                    )
                  })}
                </ul>
                <div style={{ marginTop: '16px', display: 'flex', justifyContent: 'flex-end', gap: '8px' }}>
                  <button type="button" className="btn btn-secondary" onClick={() => setArchiveOpen(false)}>
                    Schließen
                  </button>
                </div>
              </div>
            </div>
          )}
          {mediaPreview && (
            <MediaPreviewModal
              title={(mediaPreview.title || '').trim() || mediaPreview.original_filename || `Medium #${mediaPreview.id}`}
              media={mediaPreview}
              fileUrl={mediaPreview.embed_url ? null : resolveExerciseMediaFileUrl(exerciseId, mediaPreview)}
              onClose={() => setMediaPreview(null)}
              onReport={
                !mediaPreview.asset_legal_hold_active
                  ? () => {
                      setReportTarget(mediaPreview)
                      setMediaPreview(null)
                    }
                  : null
              }
            />
          )}
          {reportTarget && (
            <ReportContentModal
              targetType="media_asset"
              targetId={reportTarget.media_asset_id || reportTarget.id}
              targetLabel={reportTarget.title || reportTarget.original_filename || `Medium #${reportTarget.id}`}
              onClose={() => setReportTarget(null)}
            />
          )}
        </div>
      )}

      <ExercisePickerModal
        open={comboStationPickerIx !== null}
        onClose={() => setComboStationPickerIx(null)}
        exerciseKindAny={['simple']}
        multiSelect
        enableQuickCreateDraft
        onSelectExercises={(picked) => {
          if (comboStationPickerIx === null) return
          mergePickedExercisesIntoSlot(comboStationPickerIx, picked)
          setComboStationPickerIx(null)
        }}
      />

      <p style={{ fontSize: '12px', color: 'var(--text3)', marginTop: '16px' }}>
        <strong>KI-Ausbaustufe:</strong> Backend laut Spec{' '}
        <code style={{ fontSize: '11px' }}>POST /api/exercises/ai/suggest</code> und{' '}
        <code style={{ fontSize: '11px' }}>POST /api/exercises/{'{id}'}/ai/regenerate</code> — z. B.{' '}
        <code>OPENROUTER_API_KEY</code>, Vorschläge nur nach Trainer-Bestätigung übernehmen (siehe{' '}
        <code>api.suggestExerciseAi</code>).
      </p>
      <UnsavedChangesPrompt
        blocker={blocker}
        isBusy={saving}
        onSave={handleUnsavedDialogSave}
        onDiscardWithoutSave={() => setFormDirty(false)}
      />
    </div>
  )
}

export default ExerciseFormPageRoot