<?php

namespace App\Http\Controllers;

use App\Models\OauthClient;
use App\Services\OAuthService;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Auth;

class OauthController extends Controller
{
    public function __construct(private readonly OAuthService $oauth) {}

    public function authorize(Request $request)
    {
        $data = $request->validate([
            'response_type' => ['required', 'in:code'],
            'client_id' => ['required', 'string'],
            'redirect_uri' => ['required', 'string'],
            'scope' => ['nullable', 'string'],
            'state' => ['required', 'string', 'max:200'],
            'nonce' => ['nullable', 'string', 'max:200'],
            'code_challenge' => ['required', 'string', 'max:200'],
            'code_challenge_method' => ['required', 'in:S256'],
            'confirm' => ['nullable'],
        ]);
        $client = OauthClient::query()->where('client_id', $data['client_id'])->where('status', 'active')->first();
        if (! $client || ! $client->allowsRedirect($data['redirect_uri'])) {
            abort(400, '客户端或回调地址无效');
        }
        if (! Auth::check()) {
            $login = rtrim((string) config('qz.frontend_url'), '/').'/login?redirect='.urlencode($request->fullUrl());

            return redirect()->away($login);
        }
        $user = $request->user();
        if ($user->status !== 'active') {
            return redirect()->away($this->withQuery($data['redirect_uri'], [
                'error' => 'access_denied',
                'state' => $data['state'],
            ]));
        }
        $scopes = $this->oauth->scopes($data['scope'] ?? 'openid');
        if (! $client->is_first_party && ! $request->boolean('confirm')) {
            return view('oauth.consent', [
                'client' => $client,
                'scopes' => $scopes,
                'query' => $request->except(['_token', 'confirm']),
            ]);
        }
        $code = $this->oauth->issueCode($client, $user, $data, $scopes);

        return redirect()->away($this->withQuery($data['redirect_uri'], [
            'code' => $code,
            'state' => $data['state'],
        ]));
    }

    public function token(Request $request)
    {
        $client = $this->oauth->clientFromRequest($request);
        if (! $client) {
            return response()->json(['error' => 'invalid_client'], 401);
        }
        $result = match ($request->input('grant_type')) {
            'authorization_code' => $this->oauth->exchange($request, $client),
            'refresh_token' => $this->oauth->refresh($request, $client),
            default => ['error' => 'unsupported_grant_type'],
        };
        $status = isset($result['error']) ? 400 : 200;

        return response()->json($result, $status);
    }

    public function userinfo(Request $request)
    {
        $token = $this->bearer($request);
        $info = $token ? $this->oauth->userinfo($token) : null;
        if (! $info) {
            return response()->json(['error' => 'invalid_token'], 401);
        }

        return response()->json($info);
    }

    public function introspect(Request $request)
    {
        $client = $this->oauth->clientFromRequest($request);
        if (! $client) {
            return response()->json(['active' => false], 401);
        }

        return response()->json($this->oauth->introspect((string) $request->input('token')));
    }

    public function revoke(Request $request)
    {
        $client = $this->oauth->clientFromRequest($request);
        if (! $client) {
            return response()->json(['error' => 'invalid_client'], 401);
        }
        $this->oauth->revoke((string) $request->input('token'));

        return response()->noContent();
    }

    private function bearer(Request $request): ?string
    {
        $header = (string) $request->header('Authorization');
        if (! str_starts_with($header, 'Bearer ')) {
            return null;
        }

        return trim(substr($header, 7));
    }

    private function withQuery(string $uri, array $params): string
    {
        $joiner = str_contains($uri, '?') ? '&' : '?';

        return $uri.$joiner.http_build_query($params);
    }
}