"""
Superadmin Export/Import für zentrale Pflege der Fähigkeitsmatrix.

Fokus: Beschreibungen und Gewichtungen (skills.importance, model_skills.relevance,
skill_level_definitions, model_skill_levels) — flaches, bearbeitbares Format.

Kein Vereinsbezug — require_auth + is_superadmin; kein TenantContext.
# ACCESS_LAYER exempt: Plattform-Superadmin-Tool; globale Fähigkeitsmatrix ohne Mandantenkontext
"""
from __future__ import annotations

import csv
import io
import re
import uuid
from datetime import datetime, timezone
from typing import Any, Dict, List, Optional, Tuple

from fastapi import APIRouter, Body, Depends, HTTPException, Query
from fastapi.encoders import jsonable_encoder
from fastapi.responses import JSONResponse, PlainTextResponse

from auth import require_auth
from club_tenancy import is_superadmin
from db import get_db, get_cursor, r2d

router = APIRouter(prefix="/api/admin/matrix-editor", tags=["admin_matrix_editor"])

KIND_V1 = "shinkan.matrix_editor.v1"

SKILLS_CSV_FIELDS = [
    "skill_key",
    "main_category",
    "subcategory",
    "skill_name",
    "description",
    "importance",
    "karate_relevance",
    "relevance_level",
    "level_1",
    "level_2",
    "level_3",
    "level_4",
    "level_5",
]

MATRIX_CSV_FIELDS = [
    "model_key",
    "model_name",
    "skill_key",
    "skill_name",
    "relevance",
    "sort_order",
    "level_number",
    "level_label",
    "description",
    "observable_criteria",
]


def _require_superadmin(session: dict) -> dict:
    role = (session.get("role") or "").strip().lower()
    if not is_superadmin(role):
        raise HTTPException(status_code=403, detail="Nur Superadmins")
    return session


def _slugify_label(text: str) -> str:
    t = (text or "").strip().lower()
    t = re.sub(r"[^a-z0-9äöüß]+", "_", t, flags=re.IGNORECASE)
    t = re.sub(r"_+", "_", t).strip("_")
    return t[:48] or "gruppe"


def _skill_key(main_slug: Optional[str], cat_slug: Optional[str], name: str) -> str:
    return f"{main_slug or ''}|{cat_slug or ''}|{(name or '').strip()}"


def _model_key(import_id: Optional[str], name: str) -> str:
    iid = (import_id or "").strip()
    if iid:
        return iid
    return _slugify_label(name)


def _parse_skill_key(raw: str) -> Tuple[str, str, str]:
    parts = (raw or "").split("|", 2)
    while len(parts) < 3:
        parts.append("")
    return parts[0], parts[1], parts[2]


def _csv_response(text: str, filename: str) -> PlainTextResponse:
    return PlainTextResponse(
        content=text,
        media_type="text/csv; charset=utf-8",
        headers={"Content-Disposition": f'attachment; filename="{filename}"'},
    )


def _rows_to_csv(fieldnames: List[str], rows: List[Dict[str, Any]]) -> str:
    buf = io.StringIO()
    writer = csv.DictWriter(buf, fieldnames=fieldnames, extrasaction="ignore", lineterminator="\n")
    writer.writeheader()
    for row in rows:
        writer.writerow({k: row.get(k, "") for k in fieldnames})
    return buf.getvalue()


def _load_editor_payload(cur) -> Dict[str, Any]:
    cur.execute(
        """
        SELECT s.id, s.name, s.description, s.importance, s.karate_relevance, s.relevance_level,
               mc.slug AS main_category_slug, mc.name AS main_category_name,
               sc.slug AS category_slug, sc.name AS category_name
        FROM skills s
        LEFT JOIN skill_main_categories mc ON s.main_category_id = mc.id
        LEFT JOIN skill_categories sc ON s.category_id = sc.id
        ORDER BY mc.sort_order NULLS LAST, sc.sort_order NULLS LAST, s.sort_order NULLS LAST, s.name
        """
    )
    skill_rows = [r2d(r) for r in cur.fetchall()]
    skill_ids = [int(r["id"]) for r in skill_rows]

    level_defs: Dict[int, Dict[int, str]] = {}
    if skill_ids:
        cur.execute(
            """
            SELECT skill_id, level, description
            FROM skill_level_definitions
            WHERE skill_id = ANY(%s)
            ORDER BY skill_id, level
            """,
            (skill_ids,),
        )
        for r in cur.fetchall():
            sid = int(r["skill_id"])
            level_defs.setdefault(sid, {})[int(r["level"])] = r.get("description") or ""

    skills_out: List[Dict[str, Any]] = []
    skills_csv: List[Dict[str, Any]] = []
    for s in skill_rows:
        sid = int(s["id"])
        main_slug = s.get("main_category_slug")
        cat_slug = s.get("category_slug")
        name = (s.get("name") or "").strip()
        key = _skill_key(main_slug, cat_slug, name)
        defs = level_defs.get(sid, {})
        level_map = {str(i): defs.get(i, "") for i in range(1, 6)}
        entry = {
            "skill_key": key,
            "main_category": s.get("main_category_name") or "",
            "subcategory": s.get("category_name") or "",
            "skill_name": name,
            "description": s.get("description") or "",
            "importance": s.get("importance"),
            "karate_relevance": s.get("karate_relevance"),
            "relevance_level": s.get("relevance_level"),
            "level_definitions": level_map,
        }
        skills_out.append(entry)
        csv_row = {
            "skill_key": key,
            "main_category": entry["main_category"],
            "subcategory": entry["subcategory"],
            "skill_name": name,
            "description": entry["description"],
            "importance": entry["importance"] if entry["importance"] is not None else "",
            "karate_relevance": entry["karate_relevance"] or "",
            "relevance_level": entry["relevance_level"] if entry["relevance_level"] is not None else "",
        }
        for i in range(1, 6):
            csv_row[f"level_{i}"] = level_map.get(str(i), "")
        skills_csv.append(csv_row)

    cur.execute("SELECT id, name, import_id, level_count, status FROM maturity_models ORDER BY name")
    models_raw = [r2d(r) for r in cur.fetchall()]

    models_out: List[Dict[str, Any]] = []
    matrix_csv: List[Dict[str, Any]] = []
    for m in models_raw:
        mid = int(m["id"])
        mkey = _model_key(m.get("import_id"), m.get("name") or "")
        mname = (m.get("name") or "").strip()

        cur.execute(
            """
            SELECT level_number, name, description
            FROM model_levels
            WHERE maturity_model_id = %s
            ORDER BY sort_order ASC, level_number ASC
            """,
            (mid,),
        )
        levels = [r2d(r) for r in cur.fetchall()]
        level_label = {int(lv["level_number"]): lv.get("name") or "" for lv in levels}

        cur.execute(
            """
            SELECT ms.skill_id, ms.sort_order, ms.relevance, s.name AS skill_name,
                   mc.slug AS main_category_slug, sc.slug AS category_slug
            FROM model_skills ms
            JOIN skills s ON s.id = ms.skill_id
            LEFT JOIN skill_main_categories mc ON s.main_category_id = mc.id
            LEFT JOIN skill_categories sc ON s.category_id = sc.id
            WHERE ms.maturity_model_id = %s
            ORDER BY ms.sort_order ASC, ms.id ASC
            """,
            (mid,),
        )
        model_skills = [r2d(r) for r in cur.fetchall()]

        cur.execute(
            """
            SELECT msl.skill_id, msl.level_number, msl.description, msl.observable_criteria,
                   s.name AS skill_name, mc.slug AS main_category_slug, sc.slug AS category_slug
            FROM model_skill_levels msl
            JOIN skills s ON s.id = msl.skill_id
            LEFT JOIN skill_main_categories mc ON s.main_category_id = mc.id
            LEFT JOIN skill_categories sc ON s.category_id = sc.id
            WHERE msl.maturity_model_id = %s
            ORDER BY msl.skill_id, msl.level_number
            """,
            (mid,),
        )
        skill_levels = [r2d(r) for r in cur.fetchall()]

        ms_by_skill: Dict[int, Dict[str, Any]] = {int(ms["skill_id"]): ms for ms in model_skills}
        cells_by_skill: Dict[int, List[Dict[str, Any]]] = {}
        for sl in skill_levels:
            sid = int(sl["skill_id"])
            cells_by_skill.setdefault(sid, []).append(
                {
                    "level_number": int(sl["level_number"]),
                    "description": sl.get("description") or "",
                    "observable_criteria": sl.get("observable_criteria"),
                }
            )

        matrix_rows: List[Dict[str, Any]] = []
        seen_skills = set()
        for ms in model_skills:
            sid = int(ms["skill_id"])
            seen_skills.add(sid)
            skey = _skill_key(ms.get("main_category_slug"), ms.get("category_slug"), ms.get("skill_name") or "")
            matrix_rows.append(
                {
                    "skill_key": skey,
                    "skill_name": ms.get("skill_name") or "",
                    "relevance": ms.get("relevance"),
                    "sort_order": int(ms.get("sort_order") or 0),
                    "cells": cells_by_skill.get(sid, []),
                }
            )
            for cell in cells_by_skill.get(sid, []):
                ln = int(cell["level_number"])
                matrix_csv.append(
                    {
                        "model_key": mkey,
                        "model_name": mname,
                        "skill_key": skey,
                        "skill_name": ms.get("skill_name") or "",
                        "relevance": ms.get("relevance") or "",
                        "sort_order": int(ms.get("sort_order") or 0),
                        "level_number": ln,
                        "level_label": level_label.get(ln, ""),
                        "description": cell.get("description") or "",
                        "observable_criteria": cell.get("observable_criteria") or "",
                    }
                )

        for sid, cells in cells_by_skill.items():
            if sid in seen_skills:
                continue
            sample = cells[0] if cells else {}
            cur.execute(
                """
                SELECT s.name, mc.slug AS main_category_slug, sc.slug AS category_slug
                FROM skills s
                LEFT JOIN skill_main_categories mc ON s.main_category_id = mc.id
                LEFT JOIN skill_categories sc ON s.category_id = sc.id
                WHERE s.id = %s
                """,
                (sid,),
            )
            sk = r2d(cur.fetchone()) or {}
            skey = _skill_key(sk.get("main_category_slug"), sk.get("category_slug"), sk.get("name") or "")
            matrix_rows.append(
                {
                    "skill_key": skey,
                    "skill_name": sk.get("name") or "",
                    "relevance": None,
                    "sort_order": 0,
                    "cells": cells,
                }
            )
            for cell in cells:
                ln = int(cell["level_number"])
                matrix_csv.append(
                    {
                        "model_key": mkey,
                        "model_name": mname,
                        "skill_key": skey,
                        "skill_name": sk.get("name") or "",
                        "relevance": "",
                        "sort_order": 0,
                        "level_number": ln,
                        "level_label": level_label.get(ln, ""),
                        "description": cell.get("description") or "",
                        "observable_criteria": cell.get("observable_criteria") or "",
                    }
                )

        models_out.append(
            {
                "model_key": mkey,
                "model_name": mname,
                "level_count": int(m.get("level_count") or 5),
                "status": m.get("status"),
                "level_labels": [
                    {
                        "level_number": int(lv["level_number"]),
                        "name": lv.get("name") or "",
                        "description": lv.get("description"),
                    }
                    for lv in levels
                ],
                "matrix_rows": matrix_rows,
            }
        )

    return {
        "skills": skills_out,
        "skills_csv_rows": skills_csv,
        "maturity_models": models_out,
        "matrix_csv_rows": matrix_csv,
    }


def _build_skill_lookup(cur) -> Dict[str, int]:
    cur.execute(
        """
        SELECT s.id, s.name, mc.slug AS main_category_slug, sc.slug AS category_slug
        FROM skills s
        LEFT JOIN skill_main_categories mc ON s.main_category_id = mc.id
        LEFT JOIN skill_categories sc ON s.category_id = sc.id
        """
    )
    out: Dict[str, int] = {}
    for r in cur.fetchall():
        row = r2d(r)
        key = _skill_key(row.get("main_category_slug"), row.get("category_slug"), row.get("name") or "")
        out[key] = int(row["id"])
    return out


def _build_model_lookup(cur) -> Dict[str, int]:
    cur.execute("SELECT id, name, import_id FROM maturity_models")
    out: Dict[str, int] = {}
    for r in cur.fetchall():
        row = r2d(r)
        key = _model_key(row.get("import_id"), row.get("name") or "")
        out[key] = int(row["id"])
    return out


def _resolve_skill_id(
    cur,
    skill_lookup: Dict[str, int],
    *,
    skill_key: str,
    main_category: str = "",
    subcategory: str = "",
    skill_name: str = "",
) -> Optional[int]:
    key = (skill_key or "").strip()
    if key and key in skill_lookup:
        return skill_lookup[key]
    if key:
        main_slug, cat_slug, name = _parse_skill_key(key)
        if name and _skill_key(main_slug, cat_slug, name) in skill_lookup:
            return skill_lookup[_skill_key(main_slug, cat_slug, name)]
    name = (skill_name or "").strip()
    if not name:
        return None
    cur.execute(
        """
        SELECT s.id
        FROM skills s
        LEFT JOIN skill_main_categories mc ON s.main_category_id = mc.id
        LEFT JOIN skill_categories sc ON s.category_id = sc.id
        WHERE s.name = %s
          AND COALESCE(mc.name, '') = COALESCE(%s, '')
          AND COALESCE(sc.name, '') = COALESCE(%s, '')
        LIMIT 1
        """,
        (name, (main_category or "").strip() or None, (subcategory or "").strip() or None),
    )
    row = cur.fetchone()
    if row:
        return int(row["id"])
    cur.execute("SELECT id FROM skills WHERE name = %s LIMIT 1", (name,))
    row = cur.fetchone()
    return int(row["id"]) if row else None


def _optional_int(val: Any) -> Optional[int]:
    if val is None or val == "":
        return None
    try:
        return int(val)
    except (TypeError, ValueError):
        return None


def _apply_skills_import(cur, skills: List[Dict[str, Any]], skill_lookup: Dict[str, int], warnings: List[str]) -> int:
    updated = 0
    for row in skills:
        sid = _resolve_skill_id(
            cur,
            skill_lookup,
            skill_key=str(row.get("skill_key") or ""),
            main_category=str(row.get("main_category") or ""),
            subcategory=str(row.get("subcategory") or ""),
            skill_name=str(row.get("skill_name") or ""),
        )
        if not sid:
            warnings.append(f"Skill nicht gefunden: {row.get('skill_key') or row.get('skill_name')}")
            continue

        importance = row.get("importance")
        if importance == "":
            importance = None
        relevance_level = row.get("relevance_level")
        if relevance_level == "":
            relevance_level = None

        cur.execute(
            """
            UPDATE skills SET
                description = COALESCE(%s, description),
                importance = COALESCE(%s, importance),
                karate_relevance = COALESCE(%s, karate_relevance),
                relevance_level = COALESCE(%s, relevance_level),
                updated_at = NOW()
            WHERE id = %s
            """,
            (
                row.get("description"),
                importance,
                row.get("karate_relevance") if row.get("karate_relevance") != "" else None,
                relevance_level,
                sid,
            ),
        )
        updated += 1

        defs = row.get("level_definitions")
        if isinstance(defs, dict):
            for lvl_str, desc in defs.items():
                try:
                    lvl = int(lvl_str)
                except (TypeError, ValueError):
                    continue
                if lvl < 1 or lvl > 10:
                    continue
                text = (desc or "").strip()
                if not text:
                    continue
                cur.execute(
                    """
                    INSERT INTO skill_level_definitions (skill_id, level, description)
                    VALUES (%s, %s, %s)
                    ON CONFLICT (skill_id, level) DO UPDATE SET
                        description = EXCLUDED.description,
                        updated_at = NOW()
                    """,
                    (sid, lvl, text),
                )
        else:
            for i in range(1, 6):
                col = row.get(f"level_{i}")
                if col is None or str(col).strip() == "":
                    continue
                cur.execute(
                    """
                    INSERT INTO skill_level_definitions (skill_id, level, description)
                    VALUES (%s, %s, %s)
                    ON CONFLICT (skill_id, level) DO UPDATE SET
                        description = EXCLUDED.description,
                        updated_at = NOW()
                    """,
                    (sid, i, str(col).strip()),
                )
    return updated


def _apply_matrix_import(
    cur,
    models: List[Dict[str, Any]],
    model_lookup: Dict[str, int],
    skill_lookup: Dict[str, int],
    warnings: List[str],
) -> int:
    cells_updated = 0
    for model in models:
        mkey = str(model.get("model_key") or "").strip()
        mid = model_lookup.get(mkey)
        if not mid and model.get("model_name"):
            mid = model_lookup.get(_model_key(None, str(model.get("model_name"))))
        if not mid:
            warnings.append(f"Reifegradmodell nicht gefunden: {mkey or model.get('model_name')}")
            continue

        rows = model.get("matrix_rows") or []
        if not rows and model.get("cells"):
            rows = [model]

        for mrow in rows:
            sid = _resolve_skill_id(
                cur,
                skill_lookup,
                skill_key=str(mrow.get("skill_key") or ""),
                skill_name=str(mrow.get("skill_name") or ""),
            )
            if not sid:
                warnings.append(f"Matrix-Zeile: Skill nicht gefunden ({mrow.get('skill_key')})")
                continue

            relevance = mrow.get("relevance")
            if relevance is not None and str(relevance).strip() != "":
                sort_order = _optional_int(mrow.get("sort_order")) or 0
                cur.execute(
                    """
                    INSERT INTO model_skills (maturity_model_id, skill_id, sort_order, relevance)
                    VALUES (%s, %s, %s, %s)
                    ON CONFLICT (maturity_model_id, skill_id) DO UPDATE SET
                        sort_order = EXCLUDED.sort_order,
                        relevance = EXCLUDED.relevance
                    """,
                    (mid, sid, sort_order, str(relevance).strip()),
                )

            cells = mrow.get("cells") or []
            for cell in cells:
                ln = _optional_int(cell.get("level_number"))
                if ln is None:
                    continue
                desc = (cell.get("description") or "").strip()
                if not desc:
                    continue
                cur.execute(
                    """
                    INSERT INTO model_skill_levels (
                        maturity_model_id, skill_id, level_number,
                        description, observable_criteria
                    )
                    VALUES (%s, %s, %s, %s, %s)
                    ON CONFLICT (maturity_model_id, skill_id, level_number)
                    DO UPDATE SET
                        description = EXCLUDED.description,
                        observable_criteria = COALESCE(EXCLUDED.observable_criteria, model_skill_levels.observable_criteria),
                        updated_at = NOW()
                    """,
                    (
                        mid,
                        sid,
                        ln,
                        desc,
                        cell.get("observable_criteria") if cell.get("observable_criteria") else None,
                    ),
                )
                cells_updated += 1
    return cells_updated


def _parse_csv_text(text: str) -> List[Dict[str, str]]:
    reader = csv.DictReader(io.StringIO(text))
    return [dict(row) for row in reader]


def _skills_from_csv_rows(rows: List[Dict[str, str]]) -> List[Dict[str, Any]]:
    out: List[Dict[str, Any]] = []
    for row in rows:
        if not any(str(v).strip() for v in row.values()):
            continue
        entry: Dict[str, Any] = {
            "skill_key": row.get("skill_key", ""),
            "main_category": row.get("main_category", ""),
            "subcategory": row.get("subcategory", ""),
            "skill_name": row.get("skill_name", ""),
            "description": row.get("description", ""),
            "importance": _optional_int(row.get("importance")),
            "karate_relevance": row.get("karate_relevance", ""),
            "relevance_level": _optional_int(row.get("relevance_level")),
        }
        for i in range(1, 6):
            entry[f"level_{i}"] = row.get(f"level_{i}", "")
        out.append(entry)
    return out


def _matrix_from_csv_rows(rows: List[Dict[str, str]]) -> List[Dict[str, Any]]:
    by_model: Dict[str, Dict[str, Any]] = {}
    row_index: Dict[Tuple[str, str], Dict[str, Any]] = {}

    for row in rows:
        if not any(str(v).strip() for v in row.values()):
            continue
        mkey = (row.get("model_key") or "").strip()
        if not mkey:
            continue
        model = by_model.setdefault(
            mkey,
            {"model_key": mkey, "model_name": row.get("model_name") or "", "matrix_rows": []},
        )
        skey = (row.get("skill_key") or "").strip()
        row_key = (mkey, skey or (row.get("skill_name") or "").strip())
        mrow = row_index.get(row_key)
        if not mrow:
            mrow = {
                "skill_key": skey,
                "skill_name": row.get("skill_name") or "",
                "relevance": row.get("relevance") or "",
                "sort_order": _optional_int(row.get("sort_order")) or 0,
                "cells": [],
            }
            row_index[row_key] = mrow
            model["matrix_rows"].append(mrow)

        ln = _optional_int(row.get("level_number"))
        if ln is None:
            continue
        desc = (row.get("description") or "").strip()
        if not desc:
            continue
        mrow["cells"].append(
            {
                "level_number": ln,
                "description": desc,
                "observable_criteria": row.get("observable_criteria") or "",
            }
        )

    return list(by_model.values())


@router.get("/export")
def export_matrix_editor(
    format: str = Query("json", pattern="^(json|csv_skills|csv_matrix)$"),
    session: dict = Depends(require_auth),
):
    _require_superadmin(session)
    export_uid = str(uuid.uuid4())
    with get_db() as conn:
        cur = get_cursor(conn)
        payload = _load_editor_payload(cur)

    if format == "csv_skills":
        csv_text = _rows_to_csv(SKILLS_CSV_FIELDS, payload["skills_csv_rows"])
        return _csv_response(csv_text, f"faehigkeiten-katalog-{export_uid[:8]}.csv")

    if format == "csv_matrix":
        csv_text = _rows_to_csv(MATRIX_CSV_FIELDS, payload["matrix_csv_rows"])
        return _csv_response(csv_text, f"faehigkeitsmatrix-zellen-{export_uid[:8]}.csv")

    bundle = {
        "kind": KIND_V1,
        "export_version": 1,
        "bundle_export_id": export_uid,
        "exported_at": datetime.now(timezone.utc).isoformat(),
        "skills": payload["skills"],
        "maturity_models": payload["maturity_models"],
    }
    return JSONResponse(
        content=jsonable_encoder(bundle),
        headers={
            "Content-Disposition": f'attachment; filename="matrix-editor-{export_uid[:8]}.json"'
        },
    )


@router.post("/import")
def import_matrix_editor(
    data: Dict[str, Any] = Body(...),
    session: dict = Depends(require_auth),
):
    _require_superadmin(session)
    warnings: List[str] = []
    skills: List[Dict[str, Any]] = []
    models: List[Dict[str, Any]] = []

    kind = data.get("kind")
    if kind == KIND_V1:
        skills = list(data.get("skills") or [])
        models = list(data.get("maturity_models") or [])
    elif kind == "shinkan.matrix_editor.csv":
        part = (data.get("part") or "").strip().lower()
        csv_text = data.get("csv_text") or ""
        if not csv_text.strip():
            raise HTTPException(400, "csv_text fehlt")
        rows = _parse_csv_text(csv_text)
        if part == "skills":
            skills = _skills_from_csv_rows(rows)
        elif part == "matrix":
            models = _matrix_from_csv_rows(rows)
        else:
            raise HTTPException(400, "part muss skills oder matrix sein")
    else:
        raise HTTPException(400, f"Unbekanntes Format (kind={kind!r})")

    if not skills and not models:
        raise HTTPException(400, "Keine importierbaren Daten")

    with get_db() as conn:
        cur = get_cursor(conn)
        skill_lookup = _build_skill_lookup(cur)
        model_lookup = _build_model_lookup(cur)
        skills_updated = _apply_skills_import(cur, skills, skill_lookup, warnings) if skills else 0
        cells_updated = _apply_matrix_import(cur, models, model_lookup, skill_lookup, warnings) if models else 0

    return {
        "ok": True,
        "skills_updated": skills_updated,
        "matrix_cells_updated": cells_updated,
        "warnings": warnings,
    }