import json
import os
from pathlib import Path
from datetime import datetime

import yaml

try:
    from rapidfuzz import process, fuzz
    HAS_RAPIDFUZZ = True
except Exception:
    HAS_RAPIDFUZZ = False

from .normalize import normalize_unit as _normalize_unit

DATA_PATH = Path(os.getenv('AGX_DICTIONARY_PATH', '/opt/microdao-daarion/data/dictionaries/dictionaries.yaml'))
PENDING_PATH = Path(os.getenv('AGX_PENDING_PATH', '/opt/microdao-daarion/data/dictionaries/pending.jsonl'))
REDACT_KEYS = set(k.strip().lower() for k in os.getenv('AGX_AUDIT_REDACT_KEYS', 'token,secret,password,authorization,cookie,api_key,signature').split(','))


def _load():
    data = yaml.safe_load(DATA_PATH.read_text(encoding='utf-8'))
    return data


def _sanitize(obj):
    if isinstance(obj, dict):
        out = {}
        for k, v in obj.items():
            if k.lower() in REDACT_KEYS:
                out[k] = '***REDACTED***'
            else:
                out[k] = _sanitize(v)
        return out
    if isinstance(obj, list):
        return [_sanitize(v) for v in obj]
    return obj


def _suggest(term: str, items: list):
    term_cf = term.casefold().strip()
    candidates = []
    for item in items:
        if item.get('id'):
            candidates.append((item['id'], item['name'], item['id']))
        candidates.append((item['id'], item['name'], item['name']))
        for s in item.get('synonyms', []):
            candidates.append((item['id'], item['name'], s))

    scores = []
    if HAS_RAPIDFUZZ:
        choices = [c[2] for c in candidates]
        results = process.extract(term_cf, choices, scorer=fuzz.WRatio, limit=5)
        for match, score, idx in results:
            item_id, name, _ = candidates[idx]
            scores.append({"id": item_id, "name": name, "score": score / 100})
    else:
        import difflib
        for item_id, name, cand in candidates:
            score = difflib.SequenceMatcher(None, term_cf, cand.casefold()).ratio()
            scores.append({"id": item_id, "name": name, "score": score})
        scores = sorted(scores, key=lambda x: x['score'], reverse=True)[:5]

    return scores


def _match(term: str, items: list):
    term_cf = term.casefold().strip()
    for item in items:
        if term_cf == item.get('id', '').casefold():
            return item, 1.0, 'exact_id'
        if term_cf == item.get('name', '').casefold():
            return item, 0.98, 'exact_name'
        for s in item.get('synonyms', []):
            if term_cf == s.casefold():
                return item, 0.95, 'synonym'
    # fuzzy
    suggestions = _suggest(term, items)
    if suggestions:
        top = suggestions[0]
        if top['score'] >= 0.85:
            item = next((i for i in items if i.get('id') == top['id']), None)
            if item:
                return item, float(top['score']), 'fuzzy'
    return None, 0.0, 'none'


def _pending(trace_id: str, source: str, category: str, raw_term: str, suggestions: list, note: str = ''):
    PENDING_PATH.parent.mkdir(parents=True, exist_ok=True)
    record = {
        "ts": datetime.utcnow().isoformat() + 'Z',
        "trace_id": trace_id,
        "source": source,
        "category": category,
        "raw_term": raw_term,
        "suggestions": suggestions,
        "note": note
    }
    record = _sanitize(record)
    with PENDING_PATH.open('a', encoding='utf-8') as f:
        f.write(json.dumps(record, ensure_ascii=False) + '\n')


def _normalize(term: str, items: list, category: str, trace_id: str, source: str):
    item, conf, matched_by = _match(term, items)
    suggestions = _suggest(term, items)
    if not item or conf < 0.85:
        _pending(trace_id, source, category, term, suggestions)
        return {
            "status": "pending",
            "normalized_id": None,
            "canonical_name": None,
            "confidence": conf,
            "matched_by": matched_by,
            "suggestions": suggestions
        }
    return {
        "status": "ok",
        "normalized_id": item['id'],
        "canonical_name": item.get('name'),
        "confidence": conf,
        "matched_by": matched_by,
        "suggestions": suggestions
    }


def normalize_field(term: str, trace_id: str = '', source: str = 'telegram'):
    data = _load()
    return _normalize(term, data.get('fields', []), 'field', trace_id, source)


def normalize_crop(term: str, trace_id: str = '', source: str = 'telegram'):
    data = _load()
    return _normalize(term, data.get('crops', []), 'crop', trace_id, source)


def normalize_operation(term: str, trace_id: str = '', source: str = 'telegram'):
    data = _load()
    return _normalize(term, data.get('operations', []), 'operation', trace_id, source)


def normalize_material(term: str, trace_id: str = '', source: str = 'telegram'):
    data = _load()
    return _normalize(term, data.get('materials', []), 'material', trace_id, source)


def normalize_unit(term: str, trace_id: str = '', source: str = 'telegram'):
    data = _load()
    unit_id = _normalize_unit(term, data.get('units', []))
    if not unit_id:
        suggestions = _suggest(term, data.get('units', []))
        _pending(trace_id, source, 'unit', term, suggestions)
        return {
            "status": "pending",
            "normalized_id": None,
            "canonical_name": None,
            "confidence": 0.0,
            "matched_by": 'none',
            "suggestions": suggestions
        }
    item = next(u for u in data.get('units', []) if u['id'] == unit_id)
    return {
        "status": "ok",
        "normalized_id": unit_id,
        "canonical_name": item.get('id'),
        "confidence": 1.0,
        "matched_by": 'synonym',
        "suggestions": _suggest(term, data.get('units', []))
    }


def normalize_from_text(text: str, trace_id: str = '', source: str = 'telegram'):
    # naive extractor: split by comma
    parts = [p.strip() for p in text.split(',') if p.strip()]
    results = {"fields": [], "crops": [], "operations": [], "materials": [], "units": []}
    for p in parts:
        for cat, func in [
            ("fields", normalize_field),
            ("crops", normalize_crop),
            ("operations", normalize_operation),
            ("materials", normalize_material),
            ("units", normalize_unit)
        ]:
            res = func(p, trace_id=trace_id, source=source)
            if res['status'] == 'ok':
                results[cat].append({"term": p, **res})
                break
            elif res['status'] == 'pending':
                results[cat].append({"term": p, **res})
                break
    return results