"""
PIOE - Personal Intelligence & Opportunity Engine

FastAPI Backend Application
"""
from fastapi import FastAPI, Depends, HTTPException, Query, BackgroundTasks
from fastapi.staticfiles import StaticFiles
from fastapi.responses import HTMLResponse, JSONResponse
from fastapi.middleware.cors import CORSMiddleware
from sqlalchemy.orm import Session
from datetime import datetime
from typing import Optional
from pathlib import Path

from .database import get_db, init_db
from .models import Opportunity, OpportunityCategory, OpportunityStatus, Domain
from .delivery import DigestGenerator
from .ingestion import IngestionScheduler

# Initialize app
app = FastAPI(
    title="PIOE - Personal Intelligence & Opportunity Engine",
    description="Signal intelligence system for opportunities in AI, Robotics, and more",
    version="1.0.0"
)

# CORS middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Global scheduler instance
scheduler: Optional[IngestionScheduler] = None


@app.on_event("startup")
async def startup():
    """Initialize database and scheduler on startup."""
    init_db()
    global scheduler
    scheduler = IngestionScheduler()
    # Don't auto-start scheduler - let user trigger manually first
    print("PIOE Backend started. Run /api/ingest/start to begin ingestion.")


@app.on_event("shutdown")
async def shutdown():
    """Cleanup on shutdown."""
    global scheduler
    if scheduler:
        scheduler.stop()


# ============== API Routes ==============

@app.get("/", response_class=HTMLResponse)
async def serve_dashboard():
    """Serve the frontend dashboard."""
    frontend_path = Path(__file__).parent.parent / "frontend" / "index.html"
    if frontend_path.exists():
        return HTMLResponse(content=frontend_path.read_text(), status_code=200)
    return HTMLResponse(content="<h1>PIOE Dashboard - Frontend not found</h1>", status_code=200)


# ---------- Opportunities ----------

@app.get("/api/opportunities")
async def get_opportunities(
    db: Session = Depends(get_db),
    category: Optional[str] = None,
    domain: Optional[str] = None,
    status: Optional[str] = None,
    min_score: float = 0.0,
    limit: int = Query(default=50, le=200),
    offset: int = 0
):
    """Get filtered list of opportunities."""
    query = db.query(Opportunity).filter(
        Opportunity.combined_score >= min_score
    )
    
    if category:
        try:
            query = query.filter(Opportunity.category == OpportunityCategory(category))
        except ValueError:
            pass
    
    if domain:
        try:
            query = query.filter(Opportunity.domain == Domain(domain))
        except ValueError:
            pass
    
    if status:
        try:
            query = query.filter(Opportunity.status == OpportunityStatus(status))
        except ValueError:
            pass
    
    total = query.count()
    
    opportunities = query.order_by(
        Opportunity.combined_score.desc()
    ).offset(offset).limit(limit).all()
    
    return {
        "total": total,
        "limit": limit,
        "offset": offset,
        "opportunities": [
            {
                "id": o.id,
                "title": o.title,
                "category": o.category.value if o.category else None,
                "domain": o.domain.value if o.domain else None,
                "source_name": o.source_name,
                "url": o.url,
                "deadline": o.deadline.isoformat() if o.deadline else None,
                "relevance_score": o.relevance_score,
                "novelty_score": o.novelty_score,
                "credibility_score": o.credibility_score,
                "combined_score": o.combined_score,
                # PIOE 2.0 fields
                "roi_score": getattr(o, 'roi_score', None),
                "risk_level": o.risk_level.value if hasattr(o, 'risk_level') and o.risk_level else "medium",
                "region": o.region.value if hasattr(o, 'region') and o.region else "global",
                "status": o.status.value if o.status else None,
                "discovered_at": o.discovered_at.isoformat() if o.discovered_at else None,
                "raw_text": o.raw_text[:500] if o.raw_text else None
            }
            for o in opportunities
        ]
    }


@app.get("/api/opportunities/{opportunity_id}")
async def get_opportunity(opportunity_id: str, db: Session = Depends(get_db)):
    """Get single opportunity by ID with full PIOE 2.0 details."""
    opp = db.query(Opportunity).filter(Opportunity.id == opportunity_id).first()
    if not opp:
        raise HTTPException(status_code=404, detail="Opportunity not found")
    
    return {
        "id": opp.id,
        "title": opp.title,
        "category": opp.category.value if opp.category else None,
        "domain": opp.domain.value if opp.domain else None,
        "source_name": opp.source_name,
        "source_type": opp.source_type.value if opp.source_type else None,
        "url": opp.url,
        "deadline": opp.deadline.isoformat() if opp.deadline else None,
        "published_at": opp.published_at.isoformat() if opp.published_at else None,
        "discovered_at": opp.discovered_at.isoformat() if opp.discovered_at else None,
        "raw_text": opp.raw_text,
        # Core scores
        "relevance_score": opp.relevance_score,
        "novelty_score": opp.novelty_score,
        "credibility_score": opp.credibility_score,
        "signal_strength": opp.signal_strength,
        "combined_score": opp.combined_score,
        # PIOE 2.0: Decision intelligence
        "roi_score": getattr(opp, 'roi_score', None),
        "unlock_potential": getattr(opp, 'unlock_potential', None),
        "risk_level": opp.risk_level.value if hasattr(opp, 'risk_level') and opp.risk_level else "medium",
        "competition_level": getattr(opp, 'competition_level', None),
        # PIOE 2.0: Regional
        "region": opp.region.value if hasattr(opp, 'region') and opp.region else "global",
        "region_weight": getattr(opp, 'region_weight', 1.0),
        # Status and metadata
        "status": opp.status.value if opp.status else None,
        "metadata": opp.extra_data
    }


@app.get("/api/opportunities/{opportunity_id}/guidance")
async def get_action_guidance(opportunity_id: str, db: Session = Depends(get_db)):
    """PIOE 2.0: Get AI-powered action guidance for an opportunity."""
    from .intelligence import LLMClient
    
    opp = db.query(Opportunity).filter(Opportunity.id == opportunity_id).first()
    if not opp:
        raise HTTPException(status_code=404, detail="Opportunity not found")
    
    # Build opportunity dict for LLM
    opp_dict = {
        "title": opp.title,
        "category": opp.category.value if opp.category else "other",
        "domain": opp.domain.value if opp.domain else "mixed",
        "deadline": opp.deadline.isoformat() if opp.deadline else None,
        "raw_text": opp.raw_text or "",
        "roi_score": getattr(opp, 'roi_score', 0.5),
        "competition_level": getattr(opp, 'competition_level', 0.5),
        "region": opp.region.value if hasattr(opp, 'region') and opp.region else "global",
    }
    
    # Get action guidance from LLM
    llm = LLMClient.get_client()
    guidance = llm.recommend_action(opp_dict)
    
    return {
        "opportunity_id": opportunity_id,
        "guidance": guidance
    }


@app.patch("/api/opportunities/{opportunity_id}/status")
async def update_opportunity_status(
    opportunity_id: str,
    status: str,
    db: Session = Depends(get_db)
):
    """Update opportunity status (save, apply, dismiss, etc.)."""
    opp = db.query(Opportunity).filter(Opportunity.id == opportunity_id).first()
    if not opp:
        raise HTTPException(status_code=404, detail="Opportunity not found")
    
    try:
        opp.status = OpportunityStatus(status)
        db.commit()
        return {"success": True, "new_status": status}
    except ValueError:
        raise HTTPException(status_code=400, detail=f"Invalid status: {status}")


# ---------- Digest ----------

@app.get("/api/digest/daily")
async def get_daily_digest(db: Session = Depends(get_db), limit: int = 10):
    """Get today's opportunity digest."""
    generator = DigestGenerator(db)
    digest = generator.generate_daily(limit)
    return {"digest": digest}


@app.get("/api/digest/weekly")
async def get_weekly_digest(db: Session = Depends(get_db), limit: int = 25):
    """Get weekly opportunity digest."""
    generator = DigestGenerator(db)
    digest = generator.generate_weekly(limit)
    return {"digest": digest}


@app.get("/api/digest/urgent")
async def get_urgent_digest(db: Session = Depends(get_db), limit: int = 10):
    """Get urgent opportunities with approaching deadlines."""
    generator = DigestGenerator(db)
    digest = generator.generate_urgent(limit)
    return {"digest": digest}


@app.get("/api/digest/{category}")
async def get_category_digest(
    category: str,
    db: Session = Depends(get_db),
    limit: int = 10
):
    """Get digest for specific category."""
    try:
        cat = OpportunityCategory(category)
    except ValueError:
        raise HTTPException(status_code=400, detail=f"Invalid category: {category}")
    
    generator = DigestGenerator(db)
    digest = generator.generate_by_category(cat, limit)
    return {"digest": digest}


# ---------- Ingestion Control ----------

@app.post("/api/ingest/run")
async def run_ingestion(background_tasks: BackgroundTasks):
    """Trigger full ingestion manually."""
    global scheduler
    if not scheduler:
        scheduler = IngestionScheduler()
    
    background_tasks.add_task(scheduler.run_full_ingestion)
    return {"message": "Ingestion started in background"}


@app.post("/api/ingest/source/{source_name}")
async def run_source_ingestion(source_name: str, background_tasks: BackgroundTasks):
    """Trigger ingestion for specific source."""
    global scheduler
    if not scheduler:
        scheduler = IngestionScheduler()
    
    background_tasks.add_task(scheduler.ingest_single_source, source_name)
    return {"message": f"Ingestion started for {source_name}"}


@app.post("/api/ingest/start")
async def start_scheduler():
    """Start the automatic ingestion scheduler."""
    global scheduler
    if not scheduler:
        scheduler = IngestionScheduler()
    
    scheduler.start()
    return {"message": "Scheduler started"}


@app.post("/api/ingest/stop")
async def stop_scheduler():
    """Stop the automatic ingestion scheduler."""
    global scheduler
    if scheduler:
        scheduler.stop()
    return {"message": "Scheduler stopped"}


# ---------- Stats ----------

@app.get("/api/stats")
async def get_stats(db: Session = Depends(get_db)):
    """Get overview statistics."""
    from sqlalchemy import func
    
    total = db.query(Opportunity).count()
    new_count = db.query(Opportunity).filter(
        Opportunity.status == OpportunityStatus.NEW
    ).count()
    
    # Category breakdown
    categories = db.query(
        Opportunity.category, func.count(Opportunity.id)
    ).group_by(Opportunity.category).all()
    
    # Domain breakdown
    domains = db.query(
        Opportunity.domain, func.count(Opportunity.id)
    ).group_by(Opportunity.domain).all()
    
    return {
        "total_opportunities": total,
        "new_opportunities": new_count,
        "by_category": {
            cat.value if cat else "unknown": count 
            for cat, count in categories
        },
        "by_domain": {
            dom.value if dom else "unknown": count 
            for dom, count in domains
        }
    }


# ---------- AI Chat ----------

from pydantic import BaseModel

class ChatMessage(BaseModel):
    message: str

@app.post("/api/chat")
async def chat_with_opportunities(
    chat: ChatMessage,
    db: Session = Depends(get_db)
):
    """
    PIOE 2.0: AI-powered chat to search and explore opportunities.
    Ask questions like:
    - "Find me hackathons in Nigeria"
    - "What grants are available for AI projects?"
    - "Show me high ROI opportunities with low competition"
    """
    from .intelligence import LLMClient
    
    user_message = chat.message.strip()
    if not user_message:
        return {"response": "Please ask a question about opportunities.", "opportunities": []}
    
    # Get all opportunities for context (limit to recent high-scoring ones)
    opportunities = db.query(Opportunity).filter(
        Opportunity.combined_score >= 0.3
    ).order_by(Opportunity.combined_score.desc()).limit(100).all()
    
    # Build context for LLM
    opp_summaries = []
    for o in opportunities:
        summary = f"[{o.id}] {o.title} | Category: {o.category.value if o.category else 'other'} | Domain: {o.domain.value if o.domain else 'mixed'} | Region: {o.region.value if hasattr(o, 'region') and o.region else 'global'} | ROI: {getattr(o, 'roi_score', 0.5):.0%} | Risk: {o.risk_level.value if hasattr(o, 'risk_level') and o.risk_level else 'medium'}"
        opp_summaries.append(summary)
    
    opp_context = "\n".join(opp_summaries[:50]) if opp_summaries else "No opportunities found in database."
    
    # Create prompt for LLM
    prompt = f"""You are PIOE, a Personal Intelligence & Opportunity Engine assistant.
The user is from Nigeria and interested in AI, Computer Vision, Robotics, and Web3 opportunities.

AVAILABLE OPPORTUNITIES:
{opp_context}

USER QUESTION: {user_message}

Instructions:
1. Answer the user's question based on the opportunities above
2. If they're searching for specific types, list the most relevant opportunity IDs
3. Provide actionable advice
4. Be concise but helpful
5. If no matching opportunities exist, suggest what to search for

Return a JSON response:
{{
    "response": "Your helpful answer here",
    "matched_ids": ["id1", "id2"] or [] if none match,
    "suggested_action": "What the user should do next"
}}"""
    
    try:
        llm = LLMClient.get_client()
        result = llm._generate(prompt) if hasattr(llm, '_generate') else '{"response": "AI not configured", "matched_ids": [], "suggested_action": "Configure Gemini API key"}'
        
        import json
        # Try to parse JSON response
        start = result.find('{')
        end = result.rfind('}') + 1
        if start != -1 and end > start:
            parsed = json.loads(result[start:end])
            response_text = parsed.get("response", result)
            matched_ids = parsed.get("matched_ids", [])
            suggested_action = parsed.get("suggested_action", "")
        else:
            response_text = result
            matched_ids = []
            suggested_action = ""
        
        # Get the matched opportunities
        matched_opps = []
        if matched_ids:
            for opp in opportunities:
                if opp.id in matched_ids:
                    matched_opps.append({
                        "id": opp.id,
                        "title": opp.title,
                        "category": opp.category.value if opp.category else None,
                        "domain": opp.domain.value if opp.domain else None,
                        "url": opp.url,
                        "roi_score": getattr(opp, 'roi_score', None),
                        "risk_level": opp.risk_level.value if hasattr(opp, 'risk_level') and opp.risk_level else "medium",
                        "region": opp.region.value if hasattr(opp, 'region') and opp.region else "global",
                    })
        
        return {
            "response": response_text,
            "opportunities": matched_opps[:10],
            "suggested_action": suggested_action,
            "total_searched": len(opportunities)
        }
        
    except Exception as e:
        # Fallback: Simple keyword search
        keywords = user_message.lower().split()
        matched = []
        for o in opportunities:
            text = f"{o.title} {o.raw_text or ''}".lower()
            if any(kw in text for kw in keywords):
                matched.append({
                    "id": o.id,
                    "title": o.title,
                    "category": o.category.value if o.category else None,
                    "url": o.url,
                    "roi_score": getattr(o, 'roi_score', None),
                })
        
        return {
            "response": f"Found {len(matched)} opportunities matching your search. (AI unavailable: {str(e)[:50]})",
            "opportunities": matched[:10],
            "suggested_action": "Click on any opportunity for details",
            "total_searched": len(opportunities)
        }


# Mount static files (frontend assets)
frontend_dir = Path(__file__).parent.parent / "frontend"
if frontend_dir.exists():
    app.mount("/static", StaticFiles(directory=str(frontend_dir)), name="static")