from __future__ import annotations

import uuid

from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel, Field

from account_access import (
    FORGOT_MESSAGE,
    consume_password_reset,
    consume_verification,
    deliver_jobs,
    find_by_login,
    issue_password_reset,
    issue_verification,
    load_profile,
    normalize_email,
    profile_view,
    resend_verification,
    reset_message,
    verified_reset_recipients,
    verify_message,
)
from auth import create_session, hash_password, require_auth, verify_password
from db import get_db
from mailer import MailNotConfigured
from version import APP_VERSION

router = APIRouter(prefix="/api/auth", tags=["auth"])


class LoginRequest(BaseModel):
    email: str
    password: str = Field(min_length=4)


class SetupRequest(BaseModel):
    email: str
    name: str = Field(min_length=1)
    password: str = Field(min_length=4)


class ForgotRequest(BaseModel):
    email: str = Field(min_length=1)


class ResetPasswordRequest(BaseModel):
    token: str = Field(min_length=10)
    password: str = Field(min_length=4)


class VerifyEmailRequest(BaseModel):
    token: str = Field(min_length=10)


class ResendVerificationRequest(BaseModel):
    purpose: str


def _profile_count() -> int:
    with get_db() as conn:
        row = conn.execute("SELECT COUNT(*) AS n FROM profiles").fetchone()
        return int(row["n"])


@router.get("/status")
def auth_status():
    return {
        "status": "ok",
        "service": "kansho",
        "version": APP_VERSION,
        "needs_setup": _profile_count() == 0,
    }


@router.post("/setup")
def setup(req: SetupRequest):
    if _profile_count() > 0:
        raise HTTPException(409, "Setup ist bereits abgeschlossen")
    email = normalize_email(req.email)
    profile_id = str(uuid.uuid4())
    jobs: list[tuple[list[str], str, str]] = []
    with get_db() as conn:
        conn.execute(
            """
            INSERT INTO profiles (id, email, name, password_hash, role)
            VALUES (?, ?, ?, ?, 'admin')
            """,
            (profile_id, email, req.name.strip(), hash_password(req.password)),
        )
        raw = issue_verification(conn, profile_id, "primary", email)
        if raw:
            subject, body = verify_message(raw)
            jobs.append(([email], subject, body))
    _send_or_log_failure(jobs)
    token, expires = create_session(profile_id)
    return {
        "token": token,
        "profile_id": profile_id,
        "name": req.name.strip(),
        "role": "admin",
        "expires_at": expires.isoformat(),
    }


def _send_or_log_failure(jobs: list[tuple[list[str], str, str]]) -> bool:
    if not jobs:
        return True
    try:
        deliver_jobs(jobs)
    except MailNotConfigured:
        return False
    return True


@router.post("/login")
def login(req: LoginRequest):
    with get_db() as conn:
        prof = find_by_login(conn, req.email)
    if not prof or not verify_password(req.password, prof["password_hash"]):
        raise HTTPException(401, "Ungültige Zugangsdaten")
    if (prof.get("status") or "active") != "active":
        raise HTTPException(401, "Ungültige Zugangsdaten")
    token, expires = create_session(prof["id"], prof.get("session_days") or 30)
    return {
        "token": token,
        "profile_id": prof["id"],
        "name": prof["name"],
        "role": prof["role"],
        "expires_at": expires.isoformat(),
    }


@router.post("/logout")
def logout(session: dict = Depends(require_auth)):
    with get_db() as conn:
        conn.execute("DELETE FROM sessions WHERE token = ?", (session["token"],))
    return {"ok": True}


@router.get("/me")
def me(session: dict = Depends(require_auth)):
    with get_db() as conn:
        prof = profile_view(load_profile(conn, session["profile_id"]))
    if not prof:
        raise HTTPException(401, "Profil nicht gefunden")
    return prof


@router.post("/forgot-password")
def forgot_password(req: ForgotRequest):
    jobs: list[tuple[list[str], str, str]] = []
    with get_db() as conn:
        prof = find_by_login(conn, req.email)
        if prof and (prof.get("status") or "active") == "active":
            recipients = verified_reset_recipients(prof)
            if recipients:
                raw = issue_password_reset(conn, prof["id"])
                if raw:
                    subject, body = reset_message(raw)
                    jobs.append((recipients, subject, body))
    _send_or_log_failure(jobs)
    return {"ok": True, "message": FORGOT_MESSAGE}


@router.post("/reset-password")
def reset_password(req: ResetPasswordRequest):
    with get_db() as conn:
        consume_password_reset(conn, req.token, req.password)
    return {"ok": True}


@router.post("/verify-email")
def verify_email(req: VerifyEmailRequest):
    with get_db() as conn:
        return consume_verification(conn, req.token)


@router.post("/resend-verification")
def resend(req: ResendVerificationRequest, session: dict = Depends(require_auth)):
    with get_db() as conn:
        profile = load_profile(conn, session["profile_id"])
        if not profile:
            raise HTTPException(401, "Profil nicht gefunden")
        recipients, subject, body = resend_verification(conn, profile, req.purpose)
        jobs = [(recipients, subject, body)]
    if not _send_or_log_failure(jobs):
        raise HTTPException(503, "Mailversand ist nicht konfiguriert")
    return {"ok": True}