<?php

namespace App\Http\Controllers\ESign;

use App\Http\Controllers\Controller;
use App\Models\ESign\EsignAuditLog;
use App\Models\ESign\EsignContract;
use App\Models\ESign\EsignSigner;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Str;
use Illuminate\View\View;

class EsignPublicController extends Controller
{
    // ─── 화면 라우트 ───

    public function auth(string $token): View
    {
        return view('esign.sign.auth', ['token' => $token]);
    }

    public function sign(string $token): View
    {
        return view('esign.sign.sign', ['token' => $token]);
    }

    public function done(string $token): View
    {
        return view('esign.sign.done', ['token' => $token]);
    }

    // ─── 서명 API (토큰 기반, 비인증) ───

    /**
     * 토큰으로 계약/서명자 정보 조회
     */
    public function getContract(string $token): JsonResponse
    {
        $signer = EsignSigner::withoutGlobalScopes()
            ->where('access_token', $token)
            ->first();

        if (! $signer) {
            return response()->json(['success' => false, 'message' => '유효하지 않은 서명 링크입니다.'], 404);
        }

        if ($signer->token_expires_at && $signer->token_expires_at->isPast()) {
            return response()->json(['success' => false, 'message' => '서명 링크가 만료되었습니다.'], 400);
        }

        $contract = EsignContract::withoutGlobalScopes()
            ->with(['signers:id,contract_id,name,role,status,signed_at'])
            ->find($signer->contract_id);

        if (! $contract) {
            return response()->json(['success' => false, 'message' => '계약을 찾을 수 없습니다.'], 404);
        }

        EsignAuditLog::create([
            'tenant_id' => $contract->tenant_id,
            'contract_id' => $contract->id,
            'signer_id' => $signer->id,
            'action' => 'viewed',
            'ip_address' => request()->ip(),
            'user_agent' => request()->userAgent(),
            'created_at' => now(),
        ]);

        return response()->json([
            'success' => true,
            'data' => [
                'contract' => $contract,
                'signer' => [
                    'id' => $signer->id,
                    'name' => $signer->name,
                    'email' => $signer->email,
                    'role' => $signer->role,
                    'status' => $signer->status,
                ],
            ],
        ]);
    }

    /**
     * OTP 발송
     */
    public function sendOtp(string $token): JsonResponse
    {
        $signer = $this->findSigner($token);
        if (! $signer) {
            return response()->json(['success' => false, 'message' => '유효하지 않은 서명 링크입니다.'], 404);
        }

        $contract = EsignContract::withoutGlobalScopes()->find($signer->contract_id);
        if (! $contract || ! in_array($contract->status, ['pending', 'partially_signed'])) {
            return response()->json(['success' => false, 'message' => '서명할 수 없는 상태입니다.'], 400);
        }

        $otpCode = str_pad(random_int(0, 999999), 6, '0', STR_PAD_LEFT);

        $signer->update([
            'otp_code' => $otpCode,
            'otp_expires_at' => now()->addMinutes(5),
            'otp_attempts' => 0,
        ]);

        // OTP 이메일 발송
        \Illuminate\Support\Facades\Mail::to($signer->email)->send(
            new \App\Mail\EsignOtpMail($signer->name, $otpCode)
        );

        EsignAuditLog::create([
            'tenant_id' => $contract->tenant_id,
            'contract_id' => $contract->id,
            'signer_id' => $signer->id,
            'action' => 'otp_sent',
            'ip_address' => request()->ip(),
            'user_agent' => request()->userAgent(),
            'metadata' => ['email' => $signer->email],
            'created_at' => now(),
        ]);

        return response()->json(['success' => true, 'message' => '인증 코드가 발송되었습니다.']);
    }

    /**
     * OTP 검증
     */
    public function verifyOtp(Request $request, string $token): JsonResponse
    {
        $signer = $this->findSigner($token);
        if (! $signer) {
            return response()->json(['success' => false, 'message' => '유효하지 않은 서명 링크입니다.'], 404);
        }

        if ($signer->otp_attempts >= 5) {
            return response()->json(['success' => false, 'message' => '인증 시도 횟수를 초과했습니다.'], 400);
        }

        if (! $signer->otp_code || ! $signer->otp_expires_at) {
            return response()->json(['success' => false, 'message' => '인증 코드가 발송되지 않았습니다.'], 400);
        }

        if ($signer->otp_expires_at->isPast()) {
            return response()->json(['success' => false, 'message' => '인증 코드가 만료되었습니다.'], 400);
        }

        $signer->increment('otp_attempts');

        $otpCode = $request->input('otp_code');
        if ($signer->otp_code !== $otpCode) {
            return response()->json(['success' => false, 'message' => '인증 코드가 올바르지 않습니다.'], 400);
        }

        $contract = EsignContract::withoutGlobalScopes()->find($signer->contract_id);

        $signer->update([
            'auth_verified_at' => now(),
            'otp_code' => null,
            'otp_expires_at' => null,
            'status' => 'authenticated',
        ]);

        EsignAuditLog::create([
            'tenant_id' => $contract->tenant_id,
            'contract_id' => $contract->id,
            'signer_id' => $signer->id,
            'action' => 'authenticated',
            'ip_address' => request()->ip(),
            'user_agent' => request()->userAgent(),
            'created_at' => now(),
        ]);

        return response()->json([
            'success' => true,
            'data' => ['sign_session_token' => Str::random(64)],
        ]);
    }

    // ─── Private ───

    private function findSigner(string $token): ?EsignSigner
    {
        $signer = EsignSigner::withoutGlobalScopes()
            ->where('access_token', $token)
            ->first();

        if ($signer && $signer->token_expires_at && $signer->token_expires_at->isPast()) {
            return null;
        }

        return $signer;
    }
}