<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use Illuminate\Support\Facades\Http;

class BffController extends Controller
{
    private function dummyAccounts(): array
    {
        return [
            'admin@caps04.local' => [
                'id' => 1,
                'name' => 'Admin Dummy',
                'email' => 'admin@caps04.local',
                'role' => 'admin',
                'password' => 'password',
            ],
            'dosen@caps04.local' => [
                'id' => 2,
                'name' => 'Dosen Dummy',
                'email' => 'dosen@caps04.local',
                'role' => 'dosen',
                'password' => 'password',
            ],
            'mahasiswa@caps04.local' => [
                'id' => 3,
                'name' => 'Mahasiswa Dummy',
                'email' => 'mahasiswa@caps04.local',
                'role' => 'mahasiswa',
                'password' => 'password',
            ],
        ];
    }

    private function encodeDummyToken(array $user): string
    {
        $payload = [
            'id' => $user['id'],
            'name' => $user['name'],
            'email' => $user['email'],
            'role' => $user['role'],
        ];

        $encoded = base64_encode(json_encode($payload));
        return 'dummy-token.' . rtrim(strtr($encoded, '+/', '-_'), '=');
    }

    private function decodeDummyToken(?string $token): ?array
    {
        if (!$token || !str_starts_with($token, 'dummy-token.')) {
            return null;
        }

        $parts = explode('.', $token, 2);
        if (count($parts) !== 2) {
            return null;
        }

        $raw = strtr($parts[1], '-_', '+/');
        $padding = strlen($raw) % 4;
        if ($padding > 0) {
            $raw .= str_repeat('=', 4 - $padding);
        }
        $decoded = base64_decode($raw, true);
        if ($decoded === false) {
            return null;
        }

        $payload = json_decode($decoded, true);
        if (!is_array($payload)) {
            return null;
        }

        return $payload;
    }

    public function login(Request $request)
    {
        $email = strtolower((string) $request->input('email'));
        $password = (string) $request->input('password');
        $accounts = $this->dummyAccounts();

        if (!isset($accounts[$email]) || $accounts[$email]['password'] !== $password) {
            return response()->json([
                'message' => 'Invalid dummy credentials.',
            ], 401);
        }

        $account = $accounts[$email];

        return response()->json([
            'token' => $this->encodeDummyToken($account),
            'user' => [
                'id' => $account['id'],
                'name' => $account['name'],
                'email' => $account['email'],
                'role' => $account['role'],
            ],
        ]);
    }

    public function me(Request $request)
    {
        $authorization = $request->header('Authorization');
        $token = null;

        if (is_string($authorization) && str_starts_with($authorization, 'Bearer ')) {
            $token = substr($authorization, 7);
        }

        $payload = $this->decodeDummyToken($token);
        if ($payload) {
            return response()->json([
                'id' => $payload['id'] ?? 0,
                'name' => $payload['name'] ?? 'Dummy User',
                'email' => $payload['email'] ?? 'dummy@example.com',
                'role' => $payload['role'] ?? 'mahasiswa',
            ]);
        }

        return response()->json([
            'id' => 1,
            'name' => 'Dummy User',
            'email' => 'dummy@example.com',
            'role' => 'mahasiswa',
        ]);
    }

    public function proxy(Request $request, string $path)
    {
        $base = rtrim(env('API_URL', ''), '/');
        abort_if($base === '', 500, 'API_URL is not set');

        $url = $base . '/' . ltrim($path, '/');
        $headers = [
            'Accept' => 'application/json',
        ];

        if ($request->hasHeader('Authorization')) {
            $headers['Authorization'] = $request->header('Authorization');
        }

        $resp = Http::send($request->method(), $url, [
            'query' => $request->query(),
            'body'  => $request->getContent(),
            'headers' => $headers,
        ]);

        return response($resp->body(), $resp->status())->withHeaders($resp->headers());
    }
}