"""
UAE Knowledge System - FastAPI Backend
Serves the HTML frontend and provides search API
"""
import json
import os
import httpx
from datetime import datetime
from pathlib import Path
from typing import Dict, List, Optional

from fastapi import FastAPI, Request
from fastapi.staticfiles import StaticFiles
from fastapi.responses import HTMLResponse, FileResponse
from pydantic import BaseModel

# Load .env file if present
try:
    from dotenv import load_dotenv
    load_dotenv(Path(__file__).parent.parent / ".env")
except ImportError:
    pass  # python-dotenv not installed

from .services import get_knowledge_base, get_retriever, search_knowledge_base, get_stats

# Google Sheets storage for persistent feedback
import sys
sys.path.insert(0, str(Path(__file__).parent.parent / "ir"))
try:
    import sheets_storage
except ImportError:
    sheets_storage = None

def is_sheets_enabled():
    """Check if sheets storage is available and configured (dynamic check)."""
    if sheets_storage is None:
        return False
    return sheets_storage.is_sheets_enabled()

# DeepL API configuration
DEEPL_API_KEY = os.environ.get("DEEPL_API_KEY", "")
DEEPL_API_URL = "https://api-free.deepl.com/v2/translate"  # Use api.deepl.com for paid plans

# ============================================================
# Path Configuration
# ============================================================
PROJECT_ROOT = Path(__file__).parent.parent
FRONTEND_DIR = PROJECT_ROOT / "frontend"
DATA_DIR = PROJECT_ROOT / "data"

# Feedback file location - use /data for HF Spaces persistence
FEEDBACK_FILE = DATA_DIR / "feedback.json"

# Translation cache file - persistent across restarts
TRANSLATION_CACHE_FILE = DATA_DIR / "translations_cache.json"

# ============================================================
# Initialize FastAPI
# ============================================================
app = FastAPI(title="UAE Knowledge System", version="2.3.0")


# ============================================================
# Request/Response Models
# ============================================================
class SearchRequest(BaseModel):
    query: str
    category: str


class FeedbackRequest(BaseModel):
    query: str
    category: str
    entity_ratings: Dict[str, Dict[str, int]]
    notes: str
    results: List[str]


class TranslateRequest(BaseModel):
    texts: List[str]  # List of texts to translate
    target_lang: str  # AR or ZH (DeepL uses ZH for Chinese)


class RatingRequest(BaseModel):
    query: str
    category: str
    entity_id: str
    entity_index: int
    rating_type: str  # 'relevance' or 'helpful'
    rating_value: int  # 0, 1, or 2 for relevance; 0 or 1 for helpful


class EntityFeedbackRequest(BaseModel):
    query_id: str  # UUID for tracking unique search sessions
    query: str
    query_timestamp: str
    entity_id: str
    entity_name: str
    rank_position: int
    rank_score: float
    ratings: Dict[str, Optional[bool]]  # {relevance, helpful, sensitivity_handling}
    comment: str
    submitted_at: str


# ============================================================
# Translation Cache (file-based, persistent across restarts)
# ============================================================
_translation_cache: Dict[str, str] = {}  # {text:lang: translated}


def load_translation_cache() -> None:
    """Load translation cache from file"""
    global _translation_cache
    if TRANSLATION_CACHE_FILE.exists():
        try:
            with open(TRANSLATION_CACHE_FILE, "r", encoding="utf-8") as f:
                _translation_cache = json.load(f)
            print(f"Loaded {len(_translation_cache)} cached translations")
        except Exception as e:
            print(f"Error loading translation cache: {e}")
            _translation_cache = {}
    else:
        _translation_cache = {}


def save_translation_cache() -> None:
    """Save translation cache to file"""
    try:
        DATA_DIR.mkdir(parents=True, exist_ok=True)
        with open(TRANSLATION_CACHE_FILE, "w", encoding="utf-8") as f:
            json.dump(_translation_cache, f, ensure_ascii=False, indent=2)
    except Exception as e:
        print(f"Error saving translation cache: {e}")


async def translate_with_deepl(texts: List[str], target_lang: str) -> List[str]:
    """Translate texts using DeepL API"""
    if not DEEPL_API_KEY:
        return texts  # Return original if no API key

    # Map our language codes to DeepL codes
    lang_map = {"ar": "AR", "cn": "ZH"}
    deepl_lang = lang_map.get(target_lang.lower(), target_lang.upper())

    # Check cache first
    results = []
    texts_to_translate = []
    text_indices = []

    for i, text in enumerate(texts):
        cache_key = f"{text}:{deepl_lang}"
        if cache_key in _translation_cache:
            results.append(_translation_cache[cache_key])
        else:
            results.append(None)  # Placeholder
            texts_to_translate.append(text)
            text_indices.append(i)

    # Translate uncached texts
    if texts_to_translate:
        try:
            async with httpx.AsyncClient() as client:
                response = await client.post(
                    DEEPL_API_URL,
                    headers={
                        "Authorization": f"DeepL-Auth-Key {DEEPL_API_KEY}"
                    },
                    data={
                        "text": texts_to_translate,
                        "target_lang": deepl_lang,
                        "source_lang": "EN"
                    },
                    timeout=30.0
                )

                if response.status_code == 200:
                    data = response.json()
                    translations = data.get("translations", [])

                    for j, trans in enumerate(translations):
                        translated_text = trans.get("text", texts_to_translate[j])
                        original_idx = text_indices[j]
                        results[original_idx] = translated_text

                        # Cache the translation
                        cache_key = f"{texts_to_translate[j]}:{deepl_lang}"
                        _translation_cache[cache_key] = translated_text

                    # Save cache to file after new translations
                    save_translation_cache()
                else:
                    # On error, use original texts
                    for j, idx in enumerate(text_indices):
                        results[idx] = texts_to_translate[j]

        except Exception as e:
            print(f"Translation error: {e}")
            # On error, use original texts
            for j, idx in enumerate(text_indices):
                results[idx] = texts_to_translate[j]

    return results


# ============================================================
# API Endpoints
# ============================================================
@app.get("/", response_class=HTMLResponse)
async def root():
    """Serve the main HTML page"""
    html_path = FRONTEND_DIR / "index.html"
    if html_path.exists():
        return FileResponse(html_path)
    return HTMLResponse("<h1>UAE Knowledge System</h1><p>index.html not found</p>")


@app.get("/api/stats")
async def api_stats():
    """Get knowledge base statistics"""
    return get_stats()


@app.post("/api/search")
async def api_search(request: SearchRequest):
    """Search the knowledge base"""
    try:
        results = search_knowledge_base(request.query, top_k=100)
        return {
            "results": results,
            "query": request.query,
            "category": request.category,
            "is_sensitive": False,
            "sensitive_topic": None,
            "sensitive_guidance": None
        }
    except Exception as e:
        import traceback
        return {"error": str(e), "traceback": traceback.format_exc()[:500]}


@app.post("/api/feedback")
async def api_feedback(request: FeedbackRequest, req: Request):
    """Save user feedback"""
    try:
        # Ensure data directory exists
        DATA_DIR.mkdir(parents=True, exist_ok=True)

        # Get client IP
        client_ip = req.headers.get("x-forwarded-for", "").split(",")[0].strip()
        if not client_ip:
            client_ip = req.client.host if req.client else "unknown"

        feedback = {
            "timestamp": datetime.now().isoformat(),
            "client_ip": client_ip,
            "query": request.query,
            "category": request.category,
            "entity_ratings": request.entity_ratings,
            "notes": request.notes,
            "results": request.results
        }

        # Load existing feedback
        if FEEDBACK_FILE.exists():
            with open(FEEDBACK_FILE, "r", encoding="utf-8") as f:
                all_feedback = json.load(f)
        else:
            all_feedback = []

        all_feedback.append(feedback)

        # Save feedback
        with open(FEEDBACK_FILE, "w", encoding="utf-8") as f:
            json.dump(all_feedback, f, ensure_ascii=False, indent=2)

        return {"success": True, "total": len(all_feedback)}

    except Exception as e:
        return {"success": False, "error": str(e)}


@app.post("/api/rating")
async def api_rating(request: RatingRequest, req: Request):
    """Save individual entity rating (auto-save on click)"""
    try:
        # Ensure data directory exists
        DATA_DIR.mkdir(parents=True, exist_ok=True)

        # Get client IP
        client_ip = req.headers.get("x-forwarded-for", "").split(",")[0].strip()
        if not client_ip:
            client_ip = req.client.host if req.client else "unknown"

        rating_file = DATA_DIR / "ratings.json"

        rating = {
            "timestamp": datetime.now().isoformat(),
            "client_ip": client_ip,
            "query": request.query,
            "category": request.category,
            "entity_id": request.entity_id,
            "entity_index": request.entity_index,
            "rating_type": request.rating_type,
            "rating_value": request.rating_value
        }

        # Try Google Sheets first (persistent cloud storage)
        sheets_saved = False
        if is_sheets_enabled() and sheets_storage:
            try:
                success = sheets_storage.save_rating_to_sheets(
                    query=request.query,
                    category=request.category or "Not selected",
                    entity_id=request.entity_id,
                    entity_name=request.entity_id,  # Use ID as name fallback
                    rank=request.entity_index + 1,
                    score=0,
                    rating=f"{request.rating_type}:{request.rating_value}",
                    page=1,
                    client_ip=client_ip
                )
                sheets_saved = success
            except Exception as e:
                print(f"Google Sheets save failed: {e}")

        # Also save to local file as backup
        if rating_file.exists():
            with open(rating_file, "r", encoding="utf-8") as f:
                all_ratings = json.load(f)
        else:
            all_ratings = []

        all_ratings.append(rating)

        with open(rating_file, "w", encoding="utf-8") as f:
            json.dump(all_ratings, f, ensure_ascii=False, indent=2)

        return {"success": True, "total": len(all_ratings), "sheets_saved": sheets_saved}

    except Exception as e:
        return {"success": False, "error": str(e)}


@app.post("/api/entity-feedback")
async def api_entity_feedback(request: EntityFeedbackRequest, req: Request):
    """Save per-entity feedback with ratings and comment"""
    try:
        # Ensure data directory exists
        DATA_DIR.mkdir(parents=True, exist_ok=True)

        # Get client IP
        client_ip = req.headers.get("x-forwarded-for", "").split(",")[0].strip()
        if not client_ip:
            client_ip = req.client.host if req.client else "unknown"

        feedback_file = DATA_DIR / "entity_feedbacks.json"

        feedback = {
            "query_id": request.query_id,
            "query": request.query,
            "query_timestamp": request.query_timestamp,
            "user_ip": client_ip,
            "entity_id": request.entity_id,
            "entity_name": request.entity_name,
            "rank_position": request.rank_position,
            "rank_score": request.rank_score,
            "ratings": request.ratings,
            "comment": request.comment,
            "submitted_at": request.submitted_at
        }

        # Try Google Sheets first (persistent cloud storage)
        sheets_saved = False
        if is_sheets_enabled() and sheets_storage:
            try:
                # Convert ratings dict to string for sheet
                ratings_str = json.dumps(request.ratings) if request.ratings else ""
                success = sheets_storage.save_rating_to_sheets(
                    query=request.query,
                    category=str(request.rank_position),  # Use rank as category placeholder
                    entity_id=request.entity_id,
                    entity_name=request.entity_name,
                    rank=request.rank_position,
                    score=request.rank_score,
                    rating=ratings_str,
                    page=1,
                    client_ip=client_ip,
                    comment=request.comment or "",
                    query_id=request.query_id
                )
                sheets_saved = success
            except Exception as e:
                print(f"Google Sheets save failed: {e}")

        # Also save to local file as backup
        if feedback_file.exists():
            with open(feedback_file, "r", encoding="utf-8") as f:
                all_feedbacks = json.load(f)
        else:
            all_feedbacks = []

        all_feedbacks.append(feedback)

        with open(feedback_file, "w", encoding="utf-8") as f:
            json.dump(all_feedbacks, f, ensure_ascii=False, indent=2)

        return {"success": True, "total": len(all_feedbacks), "sheets_saved": sheets_saved}

    except Exception as e:
        return {"success": False, "error": str(e)}


@app.post("/api/translate")
async def api_translate(request: TranslateRequest):
    """Translate texts using DeepL API"""
    try:
        if not DEEPL_API_KEY:
            return {
                "success": False,
                "error": "Translation not configured (DEEPL_API_KEY not set)",
                "translations": request.texts  # Return original texts
            }

        translations = await translate_with_deepl(request.texts, request.target_lang)
        return {
            "success": True,
            "translations": translations,
            "target_lang": request.target_lang
        }
    except Exception as e:
        return {
            "success": False,
            "error": str(e),
            "translations": request.texts  # Return original on error
        }


@app.get("/api/translate/status")
async def api_translate_status():
    """Check if translation is available"""
    return {
        "available": bool(DEEPL_API_KEY),
        "provider": "DeepL" if DEEPL_API_KEY else None
    }


# ============================================================
# Static Files - Serve frontend assets
# ============================================================
# Mount CSS
app.mount("/css", StaticFiles(directory=str(FRONTEND_DIR / "css")), name="css")

# Mount JavaScript
app.mount("/js", StaticFiles(directory=str(FRONTEND_DIR / "js")), name="js")

# Mount assets (images)
app.mount("/assets", StaticFiles(directory=str(FRONTEND_DIR / "assets")), name="assets")


# ============================================================
# Startup Event
# ============================================================
@app.on_event("startup")
async def startup_event():
    """Pre-load retriever and cache on startup"""
    print("Starting UAE Knowledge System API...")
    # Load translation cache from file
    load_translation_cache()
    # Pre-load in background to speed up first request
    get_knowledge_base()
    get_retriever()
    print("System ready!")


# ============================================================
# Run with Uvicorn (for direct execution)
# ============================================================
if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=7860)