"""
Causal Lab v2 — Bibliothèque de graphes causaux + analyse empirique.

Sources d'événements : market_events (toutes catégories).
Templates de graphes  : causal_graph_templates (seed automatique au démarrage).
IA                    : GPT-4o pour recommandation de template + coefficients.

Endpoints :
  GET  /api/causal-lab/templates               — liste des templates
  GET  /api/causal-lab/template/{id}           — détail d'un template
  PUT  /api/causal-lab/template/{id}           — mettre à jour les coefficients
  GET  /api/causal-lab/market-events           — événements analysables
  POST /api/causal-lab/recommend               — GPT-4o recommande un template
  POST /api/causal-lab/analyze                 — analyse (prédiction + réel)
  GET  /api/causal-lab/analyses                — historique des analyses
  GET  /api/causal-lab/calibration             — stats de calibration par template
"""
import json
import logging
import math
from datetime import datetime, timedelta
from typing import Optional
from fastapi import APIRouter, HTTPException, Query
from pydantic import BaseModel

router = APIRouter()
logger = logging.getLogger(__name__)


# ── Initialisation DB (appelée depuis startup) ────────────────────────────────

def _init(conn):
    from services.causal_graphs import init_tables, seed_templates
    init_tables(conn)
    seed_templates(conn)


# ── Récupération des prix autour d'un événement ───────────────────────────────

def _fetch_prices(event_date_str: str, instruments: list[str]) -> dict:
    """
    Télécharge les prix autour de l'événement pour chaque instrument demandé.
    Retourne dict { instrument: [{"t": iso, "c": float}, ...] }
    """
    YFINANCE_MAP = {
        "EURUSD": "EURUSD=X",
        "XAUUSD": "GC=F",
        "SP500":  "^GSPC",
        "BRENT":  "BZ=F",
        "US2Y":   "US2YT=RR",
        "US10Y":  "^TNX",
        "EU10Y":  "GE10YT=RR",
    }

    out: dict = {"mode": "none"}
    for inst in instruments + ["US2Y", "US10Y", "EU10Y"]:
        out[inst] = []

    try:
        import yfinance as yf
        event_dt = datetime.strptime(event_date_str[:10], "%Y-%m-%d")
        days_ago = (datetime.utcnow() - event_dt).days

        # Intraday 5min (< 55 jours) pour les FX / actifs principaux
        use_intraday = days_ago < 55

        for inst in instruments:
            sym = YFINANCE_MAP.get(inst)
            if not sym:
                continue
            try:
                if use_intraday:
                    start = (event_dt - timedelta(days=1)).strftime("%Y-%m-%d")
                    end   = (event_dt + timedelta(days=2)).strftime("%Y-%m-%d")
                    df    = yf.download(sym, start=start, end=end,
                                        interval="5m", progress=False, auto_adjust=True)
                    if df is not None and len(df) > 0:
                        if hasattr(df.columns, "levels"):
                            df.columns = df.columns.get_level_values(0)
                        day_df = df[df.index.date == event_dt.date()]
                        rows = [
                            {"t": idx.isoformat(), "c": round(float(row["Close"]), 5)}
                            for idx, row in day_df.iterrows()
                            if not math.isnan(float(row["Close"]))
                        ]
                        if len(rows) >= 6:
                            out[inst] = rows
                            out["mode"] = "intraday_5m"
                            continue

                # Fallback journalier
                start = (event_dt - timedelta(days=5)).strftime("%Y-%m-%d")
                end   = (event_dt + timedelta(days=5)).strftime("%Y-%m-%d")
                df    = yf.download(sym, start=start, end=end,
                                    interval="1d", progress=False, auto_adjust=True)
                if df is not None and len(df) > 0:
                    if hasattr(df.columns, "levels"):
                        df.columns = df.columns.get_level_values(0)
                    out[inst] = [
                        {"t": str(idx.date()), "c": round(float(row["Close"]), 5)}
                        for idx, row in df.iterrows()
                        if float(row["Close"]) == float(row["Close"])
                    ]
                    if out["mode"] == "none":
                        out["mode"] = "daily"
            except Exception as e:
                logger.debug(f"[causal_lab] price {sym}: {e}")

        # Taux (toujours en journalier)
        start = (event_dt - timedelta(days=4)).strftime("%Y-%m-%d")
        end   = (event_dt + timedelta(days=4)).strftime("%Y-%m-%d")
        for key in ["US2Y", "US10Y", "EU10Y"]:
            sym = YFINANCE_MAP.get(key)
            if not sym:
                continue
            try:
                df = yf.download(sym, start=start, end=end,
                                 interval="1d", progress=False, auto_adjust=True)
                if df is None or len(df) == 0:
                    continue
                if hasattr(df.columns, "levels"):
                    df.columns = df.columns.get_level_values(0)
                out[key] = [
                    {"t": str(idx.date()), "c": round(float(row["Close"]), 3)}
                    for idx, row in df.iterrows()
                    if float(row["Close"]) == float(row["Close"])
                ]
            except Exception as e:
                logger.debug(f"[causal_lab] yield {sym}: {e}")

    except Exception as e:
        logger.error(f"[causal_lab] _fetch_prices: {e}")

    return out


def _drift_metrics(prices: dict, event_date_str: str, inst: str) -> dict:
    series = prices.get(inst, [])
    mode   = prices.get("mode", "none")
    edate  = event_date_str[:10]

    empty = {"pre_pips": None, "post_pips": None, "drift_ratio": None, "leak": "unknown"}
    if not series:
        return empty

    if mode == "intraday_5m":
        n = len(series)
        if n < 8:
            return empty
        mid = n // 2
        # Convertir en pips (×10000 pour FX, ×10 pour or/pétrole/SP500)
        mult = 10000 if inst in ("EURUSD",) else 10
        pre_pips  = round((series[mid - 1]["c"] - series[0]["c"])   * mult)
        post_pips = round((series[-1]["c"]       - series[mid]["c"]) * mult)
    else:
        pre  = [b for b in series if b["t"] <  edate]
        same = [b for b in series if b["t"] == edate]
        if not pre or not same:
            return empty
        mult = 10000 if inst in ("EURUSD",) else 10
        pre_pips  = None
        post_pips = round((same[0]["c"] - pre[-1]["c"]) * mult)

    ratio: Optional[float] = None
    if pre_pips is not None and post_pips and post_pips != 0:
        ratio = round(pre_pips / post_pips, 3)

    leak = "unknown"
    if ratio is not None:
        ar = abs(ratio)
        leak = "high" if ar > 0.5 else "medium" if ar > 0.25 else "low"

    return {"pre_pips": pre_pips, "post_pips": post_pips, "drift_ratio": ratio, "leak": leak}


def _yield_delta(series: list, event_date: str) -> Optional[float]:
    if not series:
        return None
    pre  = [b for b in series if b["t"] <  event_date]
    post = [b for b in series if b["t"] >= event_date]
    if not pre or not post:
        return None
    return round(post[0]["c"] - pre[-1]["c"], 3)


def _activation_score(node_values: dict, actual_moves: dict, template_graph: dict) -> dict:
    """
    Compare les sorties du graphe (outputs) aux mouvements réels.
    Retourne {score, nodes: {node_id: {pred, act, status}}}
    """
    output_nodes = [n for n in template_graph.get("nodes", []) if n.get("type") == "output"]
    nodes_detail: dict = {}
    correct = 0
    evaluated = 0

    for node in output_nodes:
        nid  = node["id"]
        inst = node.get("instrument", "")
        pred = node_values.get(nid)
        act  = actual_moves.get(inst)

        if pred is None or act is None:
            status = "unknown"
        elif abs(pred) < 2 and abs(act) < 2:
            status = "neutral"
        elif (pred > 0) == (act > 0):
            status = "correct"
            correct += 1
            evaluated += 1
        else:
            status = "wrong"
            evaluated += 1

        nodes_detail[nid] = {
            "pred":   round(pred, 2) if pred is not None else None,
            "act":    round(act,  2) if act  is not None else None,
            "status": status,
            "label":  node.get("label", nid),
        }

    score = round(correct / evaluated, 2) if evaluated else None
    return {"score": score, "nodes": nodes_detail, "correct": correct, "total": evaluated}


# ── Helpers GPT-4o ─────────────────────────────────────────────────────────────

def _gpt4o_recommend(event: dict, templates: list) -> dict:
    """Appelle GPT-4o pour recommander un template + coefficients."""
    try:
        from services.database import get_config
        import openai
        key = get_config("openai_api_key") or ""
        if not key:
            return {"error": "GPT-4o non configuré (clé OpenAI manquante)"}

        client = openai.OpenAI(api_key=key)

        template_summary = [
            {
                "id":          t["id"],
                "name":        t["name"],
                "category":    t["category"],
                "sub_type":    t.get("sub_type", ""),
                "instruments": t.get("instruments", []),
                "description": t.get("description", ""),
            }
            for t in templates
        ]

        system_prompt = (
            "You are a macro market analyst and causal graph specialist for the GeoOptions platform. "
            "Given a market event and a library of causal graph templates, recommend the most appropriate template "
            "and suggest any coefficient adjustments. Respond with a JSON object only."
        )

        user_prompt = f"""Market event to analyze:
- Name: {event.get('name')}
- Category: {event.get('category')}
- Sub-type: {event.get('sub_type', '')}
- Description: {event.get('description', '')}
- Market impact: {event.get('market_impact', '')}
- Affected assets: {event.get('affected_assets', '')}
- Impact score: {event.get('impact_score', '')}
- Surprise (%): {event.get('surprise_pct', 'N/A')}
- Expected: {event.get('expected_value', 'N/A')}
- Actual: {event.get('actual_value', 'N/A')}

Available templates:
{json.dumps(template_summary, ensure_ascii=False, indent=2)}

Respond with this exact JSON structure:
{{
  "template_id": <int or null>,
  "template_name": "<name>",
  "confidence": <0.0-1.0>,
  "rationale": "<2-3 sentences explaining why this template fits>",
  "coefficient_suggestions": {{
    "<coef_key>": <suggested_value>
  }},
  "instrument_focus": ["<primary instrument>"],
  "alternative_template_id": <int or null>,
  "notes": "<any additional context>"
}}"""

        resp = client.chat.completions.create(
            model="gpt-4o",
            messages=[
                {"role": "system", "content": system_prompt},
                {"role": "user",   "content": user_prompt},
            ],
            response_format={"type": "json_object"},
            temperature=0.3,
            max_tokens=600,
        )
        raw = resp.choices[0].message.content or "{}"
        return json.loads(raw)

    except Exception as e:
        logger.error(f"[causal_lab] GPT-4o recommend: {e}")
        return {"error": str(e)}


# ── Schémas Pydantic ──────────────────────────────────────────────────────────

class UpdateCoefRequest(BaseModel):
    coefficients: dict  # {coef_key: float}


class CreateTemplateRequest(BaseModel):
    name: str
    category: str
    sub_type: str = ""
    description: str = ""
    instruments: list = ["EURUSD"]
    graph_json: dict
    ai_rationale: str = ""


class RecommendRequest(BaseModel):
    market_event_id: int


class AnalyzeRequest(BaseModel):
    market_event_id: int
    template_id: int
    instrument: str = "EURUSD"
    inputs: dict = {}
    coef_overrides: dict = {}


# ── Endpoints ─────────────────────────────────────────────────────────────────

@router.get("/api/causal-lab/debug")
def debug_causal():
    """Endpoint de diagnostic — vérifie que causal_graphs est bien chargé."""
    try:
        from services.database import get_conn
        from services.causal_graphs import BUILT_IN_TEMPLATES, init_tables, seed_templates
        conn = get_conn()
        init_tables(conn)
        seed_templates(conn)
        count = conn.execute("SELECT COUNT(*) FROM causal_graph_templates").fetchone()[0]
        conn.close()
        return {
            "built_in_templates": len(BUILT_IN_TEMPLATES),
            "db_templates": count,
            "status": "ok",
        }
    except Exception as e:
        import traceback
        return {"status": "error", "error": str(e), "trace": traceback.format_exc()}


@router.get("/api/causal-lab/templates")
def list_templates(category: str = Query("")):
    try:
        from services.database import get_conn
        from services.causal_graphs import get_templates
        conn = get_conn()
        _init(conn)
        data = get_templates(conn, category)
        conn.close()
        print(f"[causal_lab] list_templates → {len(data)} templates (category={category!r})", flush=True)
        return data
    except Exception as e:
        import traceback
        print(f"[causal_lab] list_templates ERROR: {e}\n{traceback.format_exc()}", flush=True)
        logger.error(f"[causal_lab] list_templates: {e}")
        raise HTTPException(500, str(e))


@router.post("/api/causal-lab/template")
def create_template(body: CreateTemplateRequest):
    """Crée un nouveau template utilisateur."""
    try:
        from services.database import get_conn
        from services.causal_graphs import init_tables, seed_templates
        conn = get_conn()
        init_tables(conn); seed_templates(conn)
        existing = conn.execute(
            "SELECT id FROM causal_graph_templates WHERE name = ?", (body.name,)
        ).fetchone()
        if existing:
            raise HTTPException(409, f"Un template nommé '{body.name}' existe déjà")
        cur = conn.execute("""
            INSERT INTO causal_graph_templates
                (name, category, sub_type, instruments, description, graph_json, ai_rationale, created_by)
            VALUES (?, ?, ?, ?, ?, ?, ?, 'user')
        """, (
            body.name, body.category, body.sub_type,
            json.dumps(body.instruments), body.description,
            json.dumps(body.graph_json), body.ai_rationale,
        ))
        conn.commit()
        new_id = cur.lastrowid
        conn.close()
        return {"id": new_id, "name": body.name}
    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"[causal_lab] create_template: {e}")
        raise HTTPException(500, str(e))


@router.delete("/api/causal-lab/template/{template_id}")
def delete_template(template_id: int):
    """Supprime un template utilisateur (les templates system sont protégés)."""
    try:
        from services.database import get_conn
        conn = get_conn()
        row = conn.execute(
            "SELECT created_by FROM causal_graph_templates WHERE id = ?", (template_id,)
        ).fetchone()
        if not row:
            conn.close(); raise HTTPException(404, "Template introuvable")
        if row["created_by"] == "system":
            conn.close(); raise HTTPException(403, "Les templates système ne peuvent pas être supprimés")
        conn.execute("DELETE FROM causal_graph_templates WHERE id = ?", (template_id,))
        conn.commit(); conn.close()
        return {"ok": True}
    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"[causal_lab] delete_template {template_id}: {e}")
        raise HTTPException(500, str(e))


@router.get("/api/causal-lab/template/{template_id}")
def get_template_detail(template_id: int):
    try:
        from services.database import get_conn
        from services.causal_graphs import get_template, init_tables, seed_templates
        conn = get_conn()
        init_tables(conn)
        seed_templates(conn)
        tmpl = get_template(conn, template_id)
        conn.close()
        if not tmpl:
            raise HTTPException(404, "Template introuvable")
        return tmpl
    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"[causal_lab] get_template {template_id}: {e}")
        raise HTTPException(500, str(e))


@router.put("/api/causal-lab/template/{template_id}")
def update_template(template_id: int, body: UpdateCoefRequest):
    try:
        from services.database import get_conn
        from services.causal_graphs import update_coefficients, init_tables, seed_templates
        conn = get_conn()
        init_tables(conn)
        seed_templates(conn)
        ok = update_coefficients(conn, template_id, body.coefficients)
        conn.close()
        if not ok:
            raise HTTPException(404, "Template introuvable")
        return {"ok": True}
    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"[causal_lab] update_template {template_id}: {e}")
        raise HTTPException(500, str(e))


@router.get("/api/causal-lab/market-events")
def list_market_events(
    limit: int    = Query(200, le=500),
    category: str = Query(""),
    q: str        = Query(""),
):
    """Tous les market_events analysables (avec ou sans analyse existante)."""
    try:
        from services.database import get_conn
        conn = get_conn()
        _init(conn)

        conditions = ["1=1"]
        if category:
            conditions.append(f"e.category = '{category}'")
        if q:
            safe_q = q.replace("'", "''")
            conditions.append(f"(e.name LIKE '%{safe_q}%' OR e.description LIKE '%{safe_q}%')")

        where = " AND ".join(conditions)
        rows = conn.execute(f"""
            SELECT e.id, e.name, e.category, e.sub_type,
                   e.start_date, e.end_date, e.level,
                   e.impact_score, e.market_impact, e.affected_assets,
                   e.actual_value, e.expected_value, e.surprise_pct,
                   a.id as analysis_id, a.template_id, a.activation_score,
                   a.instrument, a.analyzed_at
            FROM market_events e
            LEFT JOIN causal_event_analyses a ON a.market_event_id = e.id
            WHERE {where}
            ORDER BY e.start_date DESC
            LIMIT {limit}
        """).fetchall()
        conn.close()

        return [dict(r) for r in rows]

    except Exception as e:
        logger.error(f"[causal_lab] list_market_events: {e}")
        raise HTTPException(500, str(e))


@router.post("/api/causal-lab/recommend")
def recommend_template(body: RecommendRequest):
    """GPT-4o recommande le template le plus adapté à l'événement."""
    try:
        from services.database import get_conn
        from services.causal_graphs import get_templates, init_tables, seed_templates
        conn = get_conn()
        init_tables(conn)
        seed_templates(conn)

        ev_row = conn.execute(
            "SELECT * FROM market_events WHERE id = ?", (body.market_event_id,)
        ).fetchone()
        if not ev_row:
            conn.close()
            raise HTTPException(404, "market_event introuvable")

        event     = dict(ev_row)
        templates = get_templates(conn)
        conn.close()

        recommendation = _gpt4o_recommend(event, templates)
        return {"event": event, "recommendation": recommendation}

    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"[causal_lab] recommend: {e}")
        raise HTTPException(500, str(e))


@router.post("/api/causal-lab/analyze")
def analyze_event(body: AnalyzeRequest):
    """
    Analyse complète : évalue le template sur l'événement,
    compare aux mouvements réels, stocke le résultat.
    """
    try:
        from services.database import get_conn
        from services.causal_graphs import (
            get_template, evaluate_graph, update_calibration,
            init_tables, seed_templates,
        )
        conn = get_conn()
        init_tables(conn)
        seed_templates(conn)

        ev_row = conn.execute(
            "SELECT * FROM market_events WHERE id = ?", (body.market_event_id,)
        ).fetchone()
        if not ev_row:
            conn.close()
            raise HTTPException(404, "market_event introuvable")
        event = dict(ev_row)

        tmpl = get_template(conn, body.template_id)
        if not tmpl:
            conn.close()
            raise HTTPException(404, "Template introuvable")

        graph = tmpl["graph_json"]

        # Inputs de base depuis l'événement
        inputs = {}
        mapping = graph.get("input_mapping", {})
        for input_id, cfg in mapping.items():
            src = cfg.get("source", "")
            if src == "surprise"         and event.get("surprise_pct") is not None:
                inputs[input_id] = float(event["surprise_pct"])
            elif src == "impact_score_scaled" and event.get("impact_score") is not None:
                inputs[input_id] = float(event["impact_score"]) / 10.0
            elif src == "impact_score_pct" and event.get("impact_score") is not None:
                inputs[input_id] = float(event["impact_score"])
            elif src == "actual_value"   and event.get("actual_value") is not None:
                inputs[input_id] = float(event["actual_value"])

        # Inputs manuels (ex: tone_score depuis le frontend)
        inputs.update(body.inputs)

        # Évaluation du graphe
        node_values = evaluate_graph(graph, inputs, body.coef_overrides or {})

        # Prix réels
        instruments = list({body.instrument} | set(tmpl.get("instruments", [body.instrument])))
        prices = _fetch_prices(event["start_date"], instruments)
        edate  = event["start_date"][:10]

        actual_moves: dict = {}
        drift_by_inst: dict = {}
        for inst in instruments:
            drift = _drift_metrics(prices, event["start_date"], inst)
            drift_by_inst[inst] = drift
            if drift.get("post_pips") is not None:
                actual_moves[inst] = drift["post_pips"]

        # Activation
        activation = _activation_score(node_values, actual_moves, graph)

        # Taux
        yields = {
            "us10y": _yield_delta(prices.get("US10Y", []), edate),
            "eu10y": _yield_delta(prices.get("EU10Y", []), edate),
            "us2y":  _yield_delta(prices.get("US2Y",  []), edate),
        }

        analyzed_at = datetime.utcnow().strftime("%Y-%m-%dT%H:%M:%SZ")

        result = {
            "event":         event,
            "template_id":   body.template_id,
            "template_name": tmpl["name"],
            "instrument":    body.instrument,
            "inputs":        inputs,
            "node_values":   node_values,
            "actual_moves":  actual_moves,
            "yields":        yields,
            "activation":    activation,
            "drift":         drift_by_inst.get(body.instrument, {}),
            "prices_mode":   prices.get("mode", "none"),
            "analyzed_at":   analyzed_at,
        }

        # Persistance
        conn.execute("""
            INSERT INTO causal_event_analyses
                (market_event_id, template_id, instrument, inputs_json,
                 override_params, prediction_json, actual_json,
                 activation_score, drift_json, analyzed_at)
            VALUES (?,?,?,?,?,?,?,?,?,?)
        """, (
            body.market_event_id,
            body.template_id,
            body.instrument,
            json.dumps(inputs),
            json.dumps(body.coef_overrides),
            json.dumps(node_values),
            json.dumps(actual_moves),
            activation.get("score"),
            json.dumps(drift_by_inst.get(body.instrument, {})),
            analyzed_at,
        ))
        conn.commit()

        # Calibration
        update_calibration(conn, body.template_id, {
            "activation_score": activation.get("score"),
            "instrument":       body.instrument,
            "pred_pips":        node_values.get(body.instrument.lower(), 0) or
                                next((v for k, v in node_values.items()
                                      if body.instrument.lower() in k.lower()), 0),
            "actual_pips":      actual_moves.get(body.instrument),
            "analyzed_at":      analyzed_at,
        })
        conn.close()

        return result

    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"[causal_lab] analyze: {e}")
        raise HTTPException(500, str(e))


@router.get("/api/causal-lab/analyses")
def list_analyses(
    template_id:    int = Query(0),
    instrument:     str = Query(""),
    limit:          int = Query(100, le=500),
):
    try:
        from services.database import get_conn
        conn = get_conn()
        _init(conn)

        conditions = ["1=1"]
        if template_id:
            conditions.append(f"a.template_id = {template_id}")
        if instrument:
            conditions.append(f"a.instrument = '{instrument}'")
        where = " AND ".join(conditions)

        rows = conn.execute(f"""
            SELECT a.*, e.name as event_name, e.category, e.start_date,
                   t.name as template_name
            FROM causal_event_analyses a
            LEFT JOIN market_events e ON e.id = a.market_event_id
            LEFT JOIN causal_graph_templates t ON t.id = a.template_id
            WHERE {where}
            ORDER BY a.analyzed_at DESC
            LIMIT {limit}
        """).fetchall()
        conn.close()

        result = []
        for r in rows:
            d = dict(r)
            for f in ("inputs_json", "override_params", "prediction_json", "actual_json", "drift_json"):
                try:
                    d[f] = json.loads(d[f] or "{}")
                except Exception:
                    d[f] = {}
            result.append(d)
        return result

    except Exception as e:
        logger.error(f"[causal_lab] list_analyses: {e}")
        raise HTTPException(500, str(e))


@router.get("/api/causal-lab/calibration")
def get_calibration():
    """Statistiques de calibration par template (avg_activation, avg_pred vs avg_actual)."""
    try:
        from services.database import get_conn
        conn = get_conn()
        _init(conn)

        rows = conn.execute("""
            SELECT t.id, t.name, t.category, t.sub_type,
                   t.calibration_json, t.heuristic_ver,
                   COUNT(a.id) as n_analyses,
                   AVG(a.activation_score) as avg_activation
            FROM causal_graph_templates t
            LEFT JOIN causal_event_analyses a ON a.template_id = t.id
            GROUP BY t.id
            ORDER BY t.category, t.name
        """).fetchall()
        conn.close()

        result = []
        for r in rows:
            d = dict(r)
            try:
                d["calibration"] = json.loads(d.pop("calibration_json") or "{}")
            except Exception:
                d["calibration"] = {}
            if d.get("avg_activation") is not None:
                d["avg_activation"] = round(d["avg_activation"], 3)
            result.append(d)
        return result

    except Exception as e:
        logger.error(f"[causal_lab] calibration: {e}")
        raise HTTPException(500, str(e))