<?php

namespace App\Http\Controllers\Api;

use App\Http\Controllers\Controller;
use App\Models\FinancialGoal;
use App\Models\GoalContribution;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Auth;

class FinancialGoalController extends Controller
{
    /**
     * Listar todas las metas del usuario
     */
    public function index(Request $request)
    {
        $query = FinancialGoal::forUser(Auth::id())
            ->with('contributions')
            ->orderByRaw("FIELD(status, 'active', 'paused', 'completed', 'cancelled')")
            ->orderBy('priority', 'desc')
            ->orderBy('target_date', 'asc');
        
        if ($request->has('status')) {
            $query->where('status', $request->status);
        }
        
        $goals = $query->get();
        
        // Calcular estadísticas generales
        $activeGoals = $goals->where('status', 'active');
        $stats = [
            'total_goals' => $goals->count(),
            'active_goals' => $activeGoals->count(),
            'completed_goals' => $goals->where('status', 'completed')->count(),
            'total_target' => $activeGoals->sum('target_amount'),
            'total_saved' => $activeGoals->sum('current_amount'),
            'overall_progress' => $activeGoals->sum('target_amount') > 0 
                ? round(($activeGoals->sum('current_amount') / $activeGoals->sum('target_amount')) * 100, 1)
                : 0,
        ];
        
        return response()->json([
            'data' => $goals,
            'stats' => $stats,
        ]);
    }

    /**
     * Crear una nueva meta
     */
    public function store(Request $request)
    {
        $validated = $request->validate([
            'name' => 'required|string|max:255',
            'description' => 'nullable|string',
            'icon' => 'nullable|string|max:50',
            'color' => 'nullable|string|max:20',
            'target_amount' => 'required|numeric|min:0.01',
            'current_amount' => 'nullable|numeric|min:0',
            'currency' => 'nullable|string|size:3',
            'target_date' => 'nullable|date|after:today',
            'start_date' => 'nullable|date',
            'monthly_contribution' => 'nullable|numeric|min:0',
            'priority' => 'nullable|in:high,medium,low',
        ]);
        
        $validated['user_id'] = Auth::id();
        $validated['start_date'] = $validated['start_date'] ?? now()->format('Y-m-d');
        
        $goal = FinancialGoal::create($validated);
        
        // Si tiene monto inicial, crear contribución
        if (isset($validated['current_amount']) && $validated['current_amount'] > 0) {
            $goal->contributions()->create([
                'amount' => $validated['current_amount'],
                'contribution_date' => $validated['start_date'],
                'notes' => 'Monto inicial',
            ]);
        }
        
        return response()->json([
            'message' => 'Meta creada con éxito',
            'data' => $goal->fresh('contributions'),
        ], 201);
    }

    /**
     * Ver una meta específica
     */
    public function show($id)
    {
        $goal = FinancialGoal::forUser(Auth::id())
            ->with(['contributions' => function($q) {
                $q->orderBy('contribution_date', 'desc');
            }])
            ->findOrFail($id);
        
        return response()->json($goal);
    }

    /**
     * Actualizar una meta
     */
    public function update(Request $request, $id)
    {
        $goal = FinancialGoal::forUser(Auth::id())->findOrFail($id);
        
        $validated = $request->validate([
            'name' => 'sometimes|string|max:255',
            'description' => 'nullable|string',
            'icon' => 'nullable|string|max:50',
            'color' => 'nullable|string|max:20',
            'target_amount' => 'sometimes|numeric|min:0.01',
            'target_date' => 'nullable|date',
            'monthly_contribution' => 'nullable|numeric|min:0',
            'status' => 'sometimes|in:active,completed,paused,cancelled',
            'priority' => 'sometimes|in:high,medium,low',
        ]);
        
        $goal->update($validated);
        
        // Si se marca como completada manualmente
        if (isset($validated['status']) && $validated['status'] === 'completed' && !$goal->completed_at) {
            $goal->completed_at = now();
            $goal->save();
        }
        
        return response()->json([
            'message' => 'Meta actualizada',
            'data' => $goal->fresh('contributions'),
        ]);
    }

    /**
     * Eliminar una meta
     */
    public function destroy($id)
    {
        $goal = FinancialGoal::forUser(Auth::id())->findOrFail($id);
        $goal->delete();
        
        return response()->json([
            'message' => 'Meta eliminada',
        ]);
    }

    /**
     * Añadir contribución a una meta
     */
    public function addContribution(Request $request, $id)
    {
        $goal = FinancialGoal::forUser(Auth::id())->findOrFail($id);
        
        $validated = $request->validate([
            'amount' => 'required|numeric|min:0.01',
            'contribution_date' => 'nullable|date',
            'transaction_id' => 'nullable|exists:transactions,id',
            'notes' => 'nullable|string',
        ]);
        
        $contribution = $goal->addContribution(
            $validated['amount'],
            $validated['contribution_date'] ?? now(),
            $validated['transaction_id'] ?? null,
            $validated['notes'] ?? null
        );
        
        return response()->json([
            'message' => 'Contribución añadida',
            'data' => $goal->fresh('contributions'),
        ]);
    }

    /**
     * Eliminar contribución
     */
    public function removeContribution($goalId, $contributionId)
    {
        $goal = FinancialGoal::forUser(Auth::id())->findOrFail($goalId);
        $contribution = $goal->contributions()->findOrFail($contributionId);
        
        // Restar el monto de la meta
        $goal->current_amount -= $contribution->amount;
        if ($goal->status === 'completed') {
            $goal->status = 'active';
            $goal->completed_at = null;
        }
        $goal->save();
        
        $contribution->delete();
        
        return response()->json([
            'message' => 'Contribución eliminada',
            'data' => $goal->fresh('contributions'),
        ]);
    }
}