"""
Sniper Alerts API - Hyper-personalized auction notifications

This implements "Strategie 4: Alerts nach Maß" from analysis_3.md:
"Der User kann extrem spezifische Filter speichern:
- Informiere mich NUR, wenn eine 4-Letter .com Domain droppt, die kein 'q' oder 'x' enthält."

Endpoints:
- GET /sniper-alerts - Get user's alerts
- POST /sniper-alerts - Create new alert
- PUT /sniper-alerts/{id} - Update alert
- DELETE /sniper-alerts/{id} - Delete alert
- GET /sniper-alerts/{id}/matches - Get matched auctions
- POST /sniper-alerts/{id}/test - Test alert against current auctions
"""
import logging
from datetime import datetime
from typing import Optional, List
from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel, Field
from sqlalchemy import select, func, and_
from sqlalchemy.ext.asyncio import AsyncSession

from app.database import get_db
from app.api.deps import get_current_user
from app.models.user import User
from app.models.sniper_alert import SniperAlert, SniperAlertMatch
from app.models.auction import DomainAuction

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


# ============== Schemas ==============

class SniperAlertCreate(BaseModel):
    """Create a new sniper alert."""
    name: str = Field(..., min_length=1, max_length=100)
    description: Optional[str] = Field(None, max_length=500)
    
    # Filter criteria
    tlds: Optional[str] = Field(None, description="Comma-separated TLDs: com,io,ai")
    keywords: Optional[str] = Field(None, description="Must contain (comma-separated)")
    exclude_keywords: Optional[str] = Field(None, description="Must not contain")
    max_length: Optional[int] = Field(None, ge=1, le=63)
    min_length: Optional[int] = Field(None, ge=1, le=63)
    max_price: Optional[float] = Field(None, ge=0)
    min_price: Optional[float] = Field(None, ge=0)
    max_bids: Optional[int] = Field(None, ge=0, description="Max bids (low competition)")
    ending_within_hours: Optional[int] = Field(None, ge=1, le=168)
    platforms: Optional[str] = Field(None, description="Comma-separated platforms")
    
    # Advanced
    no_numbers: bool = False
    no_hyphens: bool = False
    exclude_chars: Optional[str] = Field(None, description="Chars to exclude: q,x,z")
    
    # Notifications
    notify_email: bool = True
    notify_sms: bool = False


class SniperAlertUpdate(BaseModel):
    """Update a sniper alert."""
    name: Optional[str] = Field(None, max_length=100)
    description: Optional[str] = Field(None, max_length=500)
    tlds: Optional[str] = None
    keywords: Optional[str] = None
    exclude_keywords: Optional[str] = None
    max_length: Optional[int] = Field(None, ge=1, le=63)
    min_length: Optional[int] = Field(None, ge=1, le=63)
    max_price: Optional[float] = Field(None, ge=0)
    min_price: Optional[float] = Field(None, ge=0)
    max_bids: Optional[int] = Field(None, ge=0)
    ending_within_hours: Optional[int] = Field(None, ge=1, le=168)
    platforms: Optional[str] = None
    no_numbers: Optional[bool] = None
    no_hyphens: Optional[bool] = None
    exclude_chars: Optional[str] = None
    notify_email: Optional[bool] = None
    notify_sms: Optional[bool] = None
    is_active: Optional[bool] = None


class SniperAlertResponse(BaseModel):
    """Sniper alert response."""
    id: int
    name: str
    description: Optional[str]
    tlds: Optional[str]
    keywords: Optional[str]
    exclude_keywords: Optional[str]
    max_length: Optional[int]
    min_length: Optional[int]
    max_price: Optional[float]
    min_price: Optional[float]
    max_bids: Optional[int]
    ending_within_hours: Optional[int]
    platforms: Optional[str]
    no_numbers: bool
    no_hyphens: bool
    exclude_chars: Optional[str]
    notify_email: bool
    notify_sms: bool
    is_active: bool
    matches_count: int
    notifications_sent: int
    last_matched_at: Optional[datetime]
    created_at: datetime
    
    class Config:
        from_attributes = True


class MatchResponse(BaseModel):
    """Alert match response."""
    id: int
    domain: str
    platform: str
    current_bid: float
    end_time: datetime
    auction_url: Optional[str]
    matched_at: datetime
    notified: bool
    
    class Config:
        from_attributes = True


# ============== Endpoints ==============

@router.get("", response_model=List[SniperAlertResponse])
async def get_sniper_alerts(
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    """Get user's sniper alerts."""
    result = await db.execute(
        select(SniperAlert)
        .where(SniperAlert.user_id == current_user.id)
        .order_by(SniperAlert.created_at.desc())
    )
    alerts = list(result.scalars().all())
    
    return [
        SniperAlertResponse(
            id=alert.id,
            name=alert.name,
            description=alert.description,
            tlds=alert.tlds,
            keywords=alert.keywords,
            exclude_keywords=alert.exclude_keywords,
            max_length=alert.max_length,
            min_length=alert.min_length,
            max_price=alert.max_price,
            min_price=alert.min_price,
            max_bids=alert.max_bids,
            ending_within_hours=alert.ending_within_hours,
            platforms=alert.platforms,
            no_numbers=alert.no_numbers,
            no_hyphens=alert.no_hyphens,
            exclude_chars=alert.exclude_chars,
            notify_email=alert.notify_email,
            notify_sms=alert.notify_sms,
            is_active=alert.is_active,
            matches_count=alert.matches_count,
            notifications_sent=alert.notifications_sent,
            last_matched_at=alert.last_matched_at,
            created_at=alert.created_at,
        )
        for alert in alerts
    ]


@router.post("", response_model=SniperAlertResponse)
async def create_sniper_alert(
    data: SniperAlertCreate,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    """Create a new sniper alert."""
    # Check alert limit based on subscription
    user_alerts = await db.execute(
        select(func.count(SniperAlert.id)).where(
            SniperAlert.user_id == current_user.id
        )
    )
    alert_count = user_alerts.scalar() or 0
    
    tier = current_user.subscription.tier if current_user.subscription else "scout"
    limits = {"scout": 2, "trader": 10, "tycoon": 50}
    max_alerts = limits.get(tier, 2)
    
    if alert_count >= max_alerts:
        raise HTTPException(
            status_code=403,
            detail=f"Alert limit reached ({max_alerts}). Upgrade for more."
        )
    
    # SMS notifications are Tycoon only
    if data.notify_sms and tier != "tycoon":
        raise HTTPException(
            status_code=403,
            detail="SMS notifications are a Tycoon feature"
        )
    
    # Build filter criteria JSON
    filter_criteria = {
        "tlds": data.tlds.split(',') if data.tlds else None,
        "keywords": data.keywords.split(',') if data.keywords else None,
        "exclude_keywords": data.exclude_keywords.split(',') if data.exclude_keywords else None,
        "max_length": data.max_length,
        "min_length": data.min_length,
        "max_price": data.max_price,
        "min_price": data.min_price,
        "max_bids": data.max_bids,
        "ending_within_hours": data.ending_within_hours,
        "platforms": data.platforms.split(',') if data.platforms else None,
        "no_numbers": data.no_numbers,
        "no_hyphens": data.no_hyphens,
        "exclude_chars": data.exclude_chars.split(',') if data.exclude_chars else None,
    }
    
    alert = SniperAlert(
        user_id=current_user.id,
        name=data.name,
        description=data.description,
        filter_criteria=filter_criteria,
        tlds=data.tlds,
        keywords=data.keywords,
        exclude_keywords=data.exclude_keywords,
        max_length=data.max_length,
        min_length=data.min_length,
        max_price=data.max_price,
        min_price=data.min_price,
        max_bids=data.max_bids,
        ending_within_hours=data.ending_within_hours,
        platforms=data.platforms,
        no_numbers=data.no_numbers,
        no_hyphens=data.no_hyphens,
        exclude_chars=data.exclude_chars,
        notify_email=data.notify_email,
        notify_sms=data.notify_sms,
    )
    
    db.add(alert)
    await db.commit()
    await db.refresh(alert)
    
    return SniperAlertResponse(
        id=alert.id,
        name=alert.name,
        description=alert.description,
        tlds=alert.tlds,
        keywords=alert.keywords,
        exclude_keywords=alert.exclude_keywords,
        max_length=alert.max_length,
        min_length=alert.min_length,
        max_price=alert.max_price,
        min_price=alert.min_price,
        max_bids=alert.max_bids,
        ending_within_hours=alert.ending_within_hours,
        platforms=alert.platforms,
        no_numbers=alert.no_numbers,
        no_hyphens=alert.no_hyphens,
        exclude_chars=alert.exclude_chars,
        notify_email=alert.notify_email,
        notify_sms=alert.notify_sms,
        is_active=alert.is_active,
        matches_count=alert.matches_count,
        notifications_sent=alert.notifications_sent,
        last_matched_at=alert.last_matched_at,
        created_at=alert.created_at,
    )


@router.put("/{id}", response_model=SniperAlertResponse)
async def update_sniper_alert(
    id: int,
    data: SniperAlertUpdate,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    """Update a sniper alert."""
    result = await db.execute(
        select(SniperAlert).where(
            and_(
                SniperAlert.id == id,
                SniperAlert.user_id == current_user.id,
            )
        )
    )
    alert = result.scalar_one_or_none()
    
    if not alert:
        raise HTTPException(status_code=404, detail="Alert not found")
    
    # Update fields
    update_fields = data.model_dump(exclude_unset=True)
    for field, value in update_fields.items():
        if hasattr(alert, field):
            setattr(alert, field, value)
    
    await db.commit()
    await db.refresh(alert)
    
    return SniperAlertResponse(
        id=alert.id,
        name=alert.name,
        description=alert.description,
        tlds=alert.tlds,
        keywords=alert.keywords,
        exclude_keywords=alert.exclude_keywords,
        max_length=alert.max_length,
        min_length=alert.min_length,
        max_price=alert.max_price,
        min_price=alert.min_price,
        max_bids=alert.max_bids,
        ending_within_hours=alert.ending_within_hours,
        platforms=alert.platforms,
        no_numbers=alert.no_numbers,
        no_hyphens=alert.no_hyphens,
        exclude_chars=alert.exclude_chars,
        notify_email=alert.notify_email,
        notify_sms=alert.notify_sms,
        is_active=alert.is_active,
        matches_count=alert.matches_count,
        notifications_sent=alert.notifications_sent,
        last_matched_at=alert.last_matched_at,
        created_at=alert.created_at,
    )


@router.delete("/{id}")
async def delete_sniper_alert(
    id: int,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    """Delete a sniper alert."""
    result = await db.execute(
        select(SniperAlert).where(
            and_(
                SniperAlert.id == id,
                SniperAlert.user_id == current_user.id,
            )
        )
    )
    alert = result.scalar_one_or_none()
    
    if not alert:
        raise HTTPException(status_code=404, detail="Alert not found")
    
    await db.delete(alert)
    await db.commit()
    
    return {"success": True, "message": "Alert deleted"}


@router.get("/{id}/matches", response_model=List[MatchResponse])
async def get_alert_matches(
    id: int,
    limit: int = 50,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    """Get matched auctions for an alert."""
    # Verify ownership
    result = await db.execute(
        select(SniperAlert).where(
            and_(
                SniperAlert.id == id,
                SniperAlert.user_id == current_user.id,
            )
        )
    )
    alert = result.scalar_one_or_none()
    
    if not alert:
        raise HTTPException(status_code=404, detail="Alert not found")
    
    matches_result = await db.execute(
        select(SniperAlertMatch)
        .where(SniperAlertMatch.alert_id == id)
        .order_by(SniperAlertMatch.matched_at.desc())
        .limit(limit)
    )
    matches = list(matches_result.scalars().all())
    
    return [
        MatchResponse(
            id=m.id,
            domain=m.domain,
            platform=m.platform,
            current_bid=m.current_bid,
            end_time=m.end_time,
            auction_url=m.auction_url,
            matched_at=m.matched_at,
            notified=m.notified,
        )
        for m in matches
    ]


@router.post("/{id}/test")
async def test_sniper_alert(
    id: int,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    """Test alert against current auctions."""
    # Verify ownership
    result = await db.execute(
        select(SniperAlert).where(
            and_(
                SniperAlert.id == id,
                SniperAlert.user_id == current_user.id,
            )
        )
    )
    alert = result.scalar_one_or_none()
    
    if not alert:
        raise HTTPException(status_code=404, detail="Alert not found")
    
    # Get active auctions
    auctions_result = await db.execute(
        select(DomainAuction)
        .where(DomainAuction.is_active == True)
        .limit(500)
    )
    auctions = list(auctions_result.scalars().all())
    
    matches = []
    for auction in auctions:
        if alert.matches_domain(
            auction.domain,
            auction.tld,
            auction.current_bid,
            auction.num_bids
        ):
            matches.append({
                "domain": auction.domain,
                "platform": auction.platform,
                "current_bid": auction.current_bid,
                "num_bids": auction.num_bids,
                "end_time": auction.end_time.isoformat(),
            })
    
    return {
        "alert_name": alert.name,
        "auctions_checked": len(auctions),
        "matches_found": len(matches),
        "matches": matches[:20],  # Limit to 20 for preview
        "message": f"Found {len(matches)} matching auctions" if matches else "No matches found. Try adjusting your criteria.",
    }