"""
Opportunities (Pipeline) Router
Re-implemented to use the standard 'Sag' (Case) model.
Each 'Opportunity' is now a Case with template_key='pipeline'.
"""

from fastapi import APIRouter, HTTPException, Request, Body, Query
from app.core.database import execute_query
import logging
from typing import Optional, List, Dict, Any

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

@router.get("/opportunities", tags=["Opportunities"])
async def list_opportunities(
    q: Optional[str] = None,
    stage: Optional[str] = None,
    status: Optional[str] = None
):
    """
    List all 'pipeline' cases.
    Criteria:
    - template_key = 'pipeline'
    - OR has tag 'pipeline'
    """
    query = """
    SELECT 
        s.id,
        s.titel,
        s.status,
        s.pipeline_amount,
        s.pipeline_probability,
        s.pipeline_stage_id,
        ps.name AS pipeline_stage,
        s.created_at,
        s.deadline,
        s.beskrivelse,
        s.customer_id,
        COALESCE(c.name, 'Ukendt kunde') as customer_name,
        s.ansvarlig_bruger_id,
        COALESCE(u.full_name, u.username, 'Ingen') as ansvarlig_navn
    FROM sag_sager s
    LEFT JOIN customers c ON s.customer_id = c.id
    LEFT JOIN users u ON s.ansvarlig_bruger_id = u.user_id
    LEFT JOIN pipeline_stages ps ON ps.id = s.pipeline_stage_id
    WHERE s.deleted_at IS NULL
    AND (
        s.template_key = 'pipeline'
        OR EXISTS (
            SELECT 1
            FROM entity_tags et
            JOIN tags t ON t.id = et.tag_id
            WHERE et.entity_type = 'case'
              AND et.entity_id = s.id
              AND LOWER(t.name) = 'pipeline'
        )
        OR EXISTS (
            SELECT 1
            FROM sag_tags st
            WHERE st.sag_id = s.id
              AND st.deleted_at IS NULL
              AND LOWER(st.tag_navn) = 'pipeline'
        )
    )
    """
    
    params = []
    
    if q:
        query += " AND (s.titel ILIKE %s OR c.name ILIKE %s)"
        params.extend([f"%{q}%", f"%{q}%"])
        
    if status and status != 'all':
        if status == 'open':
            query += " AND s.status = 'åben'"
        elif status in ('won', 'lost', 'lukket'):
            query += " AND s.status = 'lukket'"

    if stage and stage != 'all':
        query += " AND LOWER(COALESCE(ps.name, '')) = LOWER(%s)"
        params.append(stage)
            
    query += " ORDER BY s.created_at DESC"
    
    try:
        results = execute_query(query, tuple(params))
        
        # Transform to match frontend expectations somewhat, or just return as cases
        # We'll return as cases but add 'amount' and 'probability' as nulls if frontend expects them
        # Actually better to update frontend to not expect them.
        return results
            
    except Exception as e:
        logger.error(f"Failed to list opportunities: {e}")
        # Return empty list on error instead of 500 to keep UI responsive
        return []

@router.post("/opportunities", tags=["Opportunities"])
async def create_opportunity(
    payload: Dict[str, Any] = Body(...)
):
    """
    Create a new 'pipeline' case.
    """
    try:
        title = payload.get("title")
        customer_id = payload.get("customer_id")
        description = payload.get("description", "")
        # Map frontend 'expected_close_date' to 'deadline'
        deadline = payload.get("expected_close_date") or None
        if deadline == "": 
            deadline = None

        if not title:
            raise HTTPException(status_code=400, detail="Mangler titel")
        if not customer_id:
            raise HTTPException(status_code=400, detail="Mangler kunde")

        # Insert as a Case with template_key='pipeline'
        query = """
        INSERT INTO sag_sager (
            titel, 
            beskrivelse, 
            customer_id, 
            status, 
            template_key, 
            deadline,
            created_by_user_id
        ) VALUES (
            %s, %s, %s, 'åben', 'pipeline', %s, 1
        ) RETURNING id, titel
        """
        
        result = execute_query(query, (title, description, customer_id, deadline))
        
        if result:
            new_case = result[0]
            return new_case
        else:
             raise HTTPException(status_code=500, detail="Kunne ikke oprette pipeline sag")
             
    except Exception as e:
        logger.error(f"Failed to create opportunity case: {e}")
        raise HTTPException(status_code=500, detail=str(e))

@router.get("/pipeline/stages", tags=["Opportunities"])
async def list_pipeline_stages():
    """List available pipeline stages from DB with a safe static fallback."""
    try:
        stages = execute_query(
            """
            SELECT id, name, color, sort_order
            FROM pipeline_stages
            WHERE COALESCE(is_active, TRUE) = TRUE
            ORDER BY sort_order ASC, id ASC
            """
        )
        if stages:
            return stages
    except Exception as e:
        logger.warning("Could not load pipeline stages from DB: %s", e)

    return [
        {"id": 1, "name": "Lead", "color": "#6c757d", "sort_order": 10},
        {"id": 2, "name": "Kontakt", "color": "#17a2b8", "sort_order": 20},
        {"id": 3, "name": "Tilbud", "color": "#ffc107", "sort_order": 30},
        {"id": 4, "name": "Forhandling", "color": "#fd7e14", "sort_order": 40},
        {"id": 5, "name": "Vundet", "color": "#28a745", "sort_order": 50},
        {"id": 6, "name": "Tabt", "color": "#dc3545", "sort_order": 60},
    ]