<?php

namespace App\Http\Controllers;

use App\Models\GatewayUser;
use App\Models\Budget;
use Illuminate\Http\Request;
use Illuminate\Support\Str;

class GatewayUserController extends Controller
{
    /**
     * Display a listing of the gateway users.
     */
    public function index(Request $request)
    {
        $query = GatewayUser::with('budget')
            ->withCount(['apiKeys', 'usageLogs']);

        // Search
        if ($request->filled('search')) {
            $search = $request->search;
            $query->where(function ($q) use ($search) {
                $q->where('user_id', 'like', "%{$search}%")
                  ->orWhere('alias', 'like', "%{$search}%");
            });
        }

        // Filter by status
        if ($request->filled('status')) {
            if ($request->status === 'active') {
                $query->active();
            } elseif ($request->status === 'blocked') {
                $query->blocked();
            }
        }

        // Sort
        $sortField = $request->get('sort', 'created_at');
        $sortDirection = $request->get('direction', 'desc');
        $query->orderBy($sortField, $sortDirection);

        $users = $query->paginate(20)->withQueryString();

        return view('gateway-users.index', compact('users'));
    }

    /**
     * Show the form for creating a new gateway user.
     */
    public function create()
    {
        $budgets = Budget::all();
        return view('gateway-users.create', compact('budgets'));
    }

    /**
     * Store a newly created gateway user in storage.
     */
    public function store(Request $request)
    {
        $validated = $request->validate([
            'alias' => 'nullable|string|max:255',
            'budget_id' => 'nullable|exists:budgets,budget_id',
            'metadata' => 'nullable|array',
        ]);

        // Generate unique user_id
        $userId = 'user_' . Str::random(16);

        $user = GatewayUser::create([
            'user_id' => $userId,
            'alias' => $validated['alias'] ?? null,
            'budget_id' => $validated['budget_id'] ?? null,
            'spend' => 0,
            'blocked' => false,
            'metadata' => $validated['metadata'] ?? [],
        ]);

        return redirect()
            ->route('gateway-users.show', $user->user_id)
            ->with('success', 'Gateway User created successfully!');
    }

    /**
     * Display the specified gateway user.
     */
    public function show(string $userId)
    {
        $user = GatewayUser::with(['apiKeys', 'budget'])
            ->findOrFail($userId);

        // Get usage statistics for last 30 days
        $stats = $this->getUserStatistics($userId, 30);

        // Get recent logs
        $recentLogs = $user->usageLogs()
            ->with('apiKey')
            ->orderByDesc('timestamp')
            ->limit(50)
            ->get();

        // Get daily usage for chart (last 30 days)
        $dailyUsage = $user->usageLogs()
            ->selectRaw('DATE(timestamp) as date, COUNT(*) as requests, SUM(cost) as cost, SUM(total_tokens) as tokens')
            ->where('timestamp', '>=', now()->subDays(30))
            ->groupBy('date')
            ->orderBy('date')
            ->get();

        return view('gateway-users.show', compact('user', 'stats', 'recentLogs', 'dailyUsage'));
    }

    /**
     * Show the form for editing the specified gateway user.
     */
    public function edit(string $userId)
    {
        $user = GatewayUser::findOrFail($userId);
        $budgets = Budget::all();
        
        return view('gateway-users.edit', compact('user', 'budgets'));
    }

    /**
     * Update the specified gateway user in storage.
     */
    public function update(Request $request, string $userId)
    {
        $user = GatewayUser::findOrFail($userId);

        $validated = $request->validate([
            'alias' => 'nullable|string|max:255',
            'budget_id' => 'nullable|exists:budgets,budget_id',
            'metadata' => 'nullable|array',
        ]);

        $user->update($validated);

        return redirect()
            ->route('gateway-users.show', $user->user_id)
            ->with('success', 'Gateway User updated successfully!');
    }

    /**
     * Remove the specified gateway user from storage.
     */
    public function destroy(string $userId)
    {
        $user = GatewayUser::findOrFail($userId);
        
        // Delete associated API keys and usage logs
        $user->apiKeys()->delete();
        $user->usageLogs()->delete();
        $user->delete();

        return redirect()
            ->route('gateway-users.index')
            ->with('success', 'Gateway User deleted successfully!');
    }

    /**
     * Toggle block status of a gateway user.
     */
    public function toggleBlock(string $userId)
    {
        $user = GatewayUser::findOrFail($userId);
        $user->blocked = !$user->blocked;
        $user->save();

        $status = $user->blocked ? 'blocked' : 'unblocked';

        return redirect()
            ->back()
            ->with('success', "User has been {$status} successfully!");
    }

    /**
     * Bulk actions for gateway users.
     */
    public function bulkAction(Request $request)
    {
        $validated = $request->validate([
            'action' => 'required|in:block,unblock,delete',
            'user_ids' => 'required|array|min:1',
            'user_ids.*' => 'exists:users,user_id',
        ]);

        $count = 0;

        switch ($validated['action']) {
            case 'block':
                GatewayUser::whereIn('user_id', $validated['user_ids'])
                    ->update(['blocked' => true]);
                $count = count($validated['user_ids']);
                $message = "{$count} user(s) have been blocked successfully!";
                break;

            case 'unblock':
                GatewayUser::whereIn('user_id', $validated['user_ids'])
                    ->update(['blocked' => false]);
                $count = count($validated['user_ids']);
                $message = "{$count} user(s) have been unblocked successfully!";
                break;

            case 'delete':
                foreach ($validated['user_ids'] as $userId) {
                    $user = GatewayUser::find($userId);
                    if ($user) {
                        $user->apiKeys()->delete();
                        $user->usageLogs()->delete();
                        $user->delete();
                        $count++;
                    }
                }
                $message = "{$count} user(s) have been deleted successfully!";
                break;
        }

        return redirect()
            ->route('gateway-users.index')
            ->with('success', $message);
    }

    /**
     * Get user statistics for a given time period.
     */
    private function getUserStatistics(string $userId, int $days)
    {
        return \App\Models\UsageLog::where('user_id', $userId)
            ->where('timestamp', '>=', now()->subDays($days))
            ->selectRaw('
                COUNT(*) as total_requests,
                SUM(prompt_tokens) as total_prompt_tokens,
                SUM(completion_tokens) as total_completion_tokens,
                SUM(total_tokens) as total_tokens,
                SUM(cost) as total_cost,
                AVG(total_tokens) as avg_tokens_per_request
            ')
            ->first();
    }
}