#!/usr/bin/env python3
"""#16 Claim-Verification Stufe 2: matche Claims gegen Bestaetigung/Widerspruch in anderen Episoden.

Vorgehen:
1. Lade Claims (default verifiable=1, optional alle).
2. Embedde jeden Claim-Text und suche per Cosinus den besten Kandidaten in anderen Episoden.
3. Bei score >= MIN_SCORE: Qwen-Verifikation: 'belegt' / 'widerspricht' / 'erweitert' / 'kein_bezug'.
4. Schreibe Treffer in neue Tabelle claim_matches.

Nutzung:
    DASHSCOPE_API_KEY=... python3 match_claims.py [db-pfad] [limit]

Optionen:
    --cross-podcast       erlaubt Treffer in anderen Podcasts
    --include-non-verifiable  matche auch Claims, die nicht als verifizierbar markiert sind
"""

import json
import os
import sqlite3
import sys
import time
from pathlib import Path

import numpy as np
from openai import OpenAI

sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
from json_utils import parse_llm_json

ROOT = Path(__file__).resolve().parent.parent
sys.path.insert(0, str(ROOT / "backend"))
from database import get_all_embeddings  # noqa: E402

DB_PATH = sys.argv[1] if len(sys.argv) > 1 else "data/db.sqlite"
LIMIT = int(sys.argv[2]) if len(sys.argv) > 2 and not sys.argv[2].startswith("--") else 500
CROSS_PODCAST = "--cross-podcast" in sys.argv
INCLUDE_NON_VERIFIABLE = "--include-non-verifiable" in sys.argv

API_KEY = os.environ.get("DASHSCOPE_API_KEY", "")
BASE_URL = "https://dashscope-intl.aliyuncs.com/compatible-mode/v1"
EMBED_MODEL = "text-embedding-v3"
LLM_MODEL = "qwen-plus"
EMBED_BATCH = 6
MIN_SCORE = 0.55
HARD_BUDGET_USD = 1.50

COST_IN = 0.0008 / 1000
COST_OUT = 0.002 / 1000

SYSTEM_PROMPT = """Du erhaeltst eine prueffbare Behauptung aus einem Podcast und einen Kandidat-Absatz aus einer anderen Episode.

Pruefe die logische Beziehung des Kandidaten zur Behauptung. Antworte NUR mit JSON:
{"relation": "belegt" | "widerspricht" | "erweitert" | "kein_bezug", "reason": "1 Satz Begruendung"}

- "belegt": der Kandidat liefert Evidenz/Daten, die die Behauptung stuetzen.
- "widerspricht": der Kandidat widerspricht der Behauptung oder nennt Gegenargumente.
- "erweitert": der Kandidat ergaenzt die Behauptung um Aspekte, ohne ihr zuzustimmen oder zu widersprechen.
- "kein_bezug": kein logischer Bezug, auch wenn das Thema verwandt ist."""


def setup_db(db):
    db.executescript("""
    CREATE TABLE IF NOT EXISTS claim_matches (
        id INTEGER PRIMARY KEY AUTOINCREMENT,
        claim_id INTEGER NOT NULL,
        target_podcast TEXT NOT NULL,
        target_episode TEXT NOT NULL,
        target_idx INTEGER NOT NULL,
        relation TEXT NOT NULL,
        reason TEXT,
        score REAL,
        FOREIGN KEY (claim_id) REFERENCES claims(id)
    );
    CREATE INDEX IF NOT EXISTS idx_claim_matches ON claim_matches(claim_id);
    CREATE INDEX IF NOT EXISTS idx_claim_matches_relation ON claim_matches(relation);
    """)


def fetch_claims(db):
    where = "WHERE 1=1"
    if not INCLUDE_NON_VERIFIABLE:
        where += " AND c.verifiable = 1"
    where += " AND NOT EXISTS (SELECT 1 FROM claim_matches m WHERE m.claim_id = c.id)"
    rows = db.execute(f"""
        SELECT c.id, c.podcast_id, c.episode_id, c.paragraph_idx, c.claim_text, c.claim_type
        FROM claims c
        {where}
        ORDER BY c.id
        LIMIT ?
    """, (LIMIT,)).fetchall()
    return rows


def embed_batch(client, texts):
    resp = client.embeddings.create(model=EMBED_MODEL, input=texts, dimensions=1024)
    return [item.embedding for item in resp.data]


def best_candidate(c_vec, vectors, meta, exclude_podcast, exclude_episode, allow_cross):
    scores = vectors @ c_vec
    order = np.argsort(scores)[::-1]
    for idx in order[:30]:
        m = meta[idx]
        if m["podcast_id"] == exclude_podcast and m["episode_id"] == exclude_episode:
            continue
        if not allow_cross and m["podcast_id"] != exclude_podcast:
            continue
        return m, float(scores[idx])
    return None, 0.0


class Budget:
    def __init__(self, hard_limit_usd):
        self.hard_limit = hard_limit_usd
        self.tokens_in = 0
        self.tokens_out = 0

    def add(self, usage):
        if usage:
            self.tokens_in += getattr(usage, "prompt_tokens", 0) or 0
            self.tokens_out += getattr(usage, "completion_tokens", 0) or 0

    def cost(self):
        return self.tokens_in * COST_IN + self.tokens_out * COST_OUT

    def over(self):
        return self.cost() > self.hard_limit


def verify(client, claim_text, candidate_text, budget):
    user_msg = (
        f"BEHAUPTUNG:\n\"{claim_text}\"\n\n"
        f"KANDIDAT-ABSATZ:\n\"{candidate_text[:1000]}\""
    )
    last_err = None
    for attempt in range(2):
        try:
            resp = client.chat.completions.create(
                model=LLM_MODEL,
                messages=[
                    {"role": "system", "content": SYSTEM_PROMPT},
                    {"role": "user", "content": user_msg},
                ],
                temperature=0.0,
                max_tokens=200,
            )
            budget.add(getattr(resp, "usage", None))
            content = resp.choices[0].message.content
            try:
                return parse_llm_json(content, expect="object"), None
            except ValueError as pe:
                last_err = f"parse: {pe}"
                break
        except Exception as e:
            last_err = str(e)
            if attempt < 1:
                time.sleep(2)
                continue
    return None, last_err


def main():
    if not API_KEY:
        print("DASHSCOPE_API_KEY nicht gesetzt.")
        sys.exit(1)
    client = OpenAI(api_key=API_KEY, base_url=BASE_URL, timeout=60.0, max_retries=1)

    db = sqlite3.connect(DB_PATH, timeout=30.0)
    db.execute("PRAGMA busy_timeout=30000")
    db.row_factory = sqlite3.Row
    setup_db(db)

    claims = fetch_claims(db)
    print(f"Claims zu matchen: {len(claims)}")
    if not claims:
        return

    print("Lade paragraph-embeddings…")
    vectors, meta = get_all_embeddings(None)
    if vectors is None:
        print("Keine Embeddings vorhanden — abbruch.")
        return
    nan_mask = np.isnan(vectors).any(axis=1)
    if nan_mask.any():
        print(f"  {nan_mask.sum()} NaN-Vektoren maskiert")
        vectors[nan_mask] = 0
    print(f"  {len(meta)} Vektoren geladen")

    print(f"Embedde {len(claims)} Claims…")
    c_vecs = []
    for i in range(0, len(claims), EMBED_BATCH):
        batch = claims[i:i + EMBED_BATCH]
        texts = [c["claim_text"][:500] for c in batch]
        try:
            embs = embed_batch(client, texts)
        except Exception as e:
            print(f"  Embedding-Batch {i // EMBED_BATCH + 1} fehler: {e}")
            time.sleep(2)
            embs = [None] * len(batch)
        for emb in embs:
            if emb is None:
                c_vecs.append(None)
            else:
                v = np.array(emb, dtype=np.float32)
                v /= np.linalg.norm(v) or 1
                c_vecs.append(v)

    budget = Budget(hard_limit_usd=HARD_BUDGET_USD)
    rel_counts = {"belegt": 0, "widerspricht": 0, "erweitert": 0, "kein_bezug": 0}
    skipped_low_score = 0
    parse_failed = 0

    for i, (c, c_vec) in enumerate(zip(claims, c_vecs)):
        if budget.over():
            print(f"!! Budget ({budget.cost():.4f} USD) erreicht — Abbruch nach {i}")
            break
        if c_vec is None:
            continue

        cand, score = best_candidate(c_vec, vectors, meta, c["podcast_id"], c["episode_id"], CROSS_PODCAST)
        if cand is None or score < MIN_SCORE:
            skipped_low_score += 1
            continue

        cand_text = db.execute(
            "SELECT text FROM paragraphs WHERE id=?", (cand["id"],)
        ).fetchone()["text"]

        result, err = verify(client, c["claim_text"], cand_text, budget)
        if result is None:
            parse_failed += 1
            continue

        rel = (result.get("relation") or "").lower()
        if rel not in rel_counts:
            rel = "kein_bezug"
        rel_counts[rel] += 1

        if rel != "kein_bezug":
            db.execute(
                "INSERT INTO claim_matches (claim_id, target_podcast, target_episode, "
                "target_idx, relation, reason, score) VALUES (?, ?, ?, ?, ?, ?, ?)",
                (c["id"], cand["podcast_id"], cand["episode_id"], cand["idx"],
                 rel, (result.get("reason") or "")[:500], score),
            )

        if (i + 1) % 20 == 0:
            db.commit()
            print(f"  [{i+1}/{len(claims)}] belegt={rel_counts['belegt']} "
                  f"widerspricht={rel_counts['widerspricht']} erweitert={rel_counts['erweitert']} "
                  f"kein_bezug={rel_counts['kein_bezug']} skipped={skipped_low_score} "
                  f"cost=${budget.cost():.4f}")
        time.sleep(0.25)

    db.commit()

    print()
    print("=== Zusammenfassung ===")
    for k, v in rel_counts.items():
        print(f"  {k}: {v}")
    print(f"  skipped (score<{MIN_SCORE}): {skipped_low_score}")
    print(f"  parse-failures:        {parse_failed}")
    print(f"  Tokens in={budget.tokens_in} out={budget.tokens_out}")
    print(f"  Kosten ~${budget.cost():.4f}")
    db.close()


if __name__ == "__main__":
    main()