<?php

use App\Models\Setting;
use App\Models\Share;
use App\Models\ShareFile;
use App\Services\FileEncryptionService;
use App\Services\ShareService;
use Illuminate\Database\Eloquent\ModelNotFoundException;
use Illuminate\Foundation\Testing\RefreshDatabase;
use Illuminate\Http\UploadedFile;
use Illuminate\Support\Facades\Hash;
use Illuminate\Support\Facades\Storage;
use Illuminate\Validation\ValidationException;
use Tests\TestCase;

pest()->extend(TestCase::class)
    ->use(RefreshDatabase::class);

beforeEach(function () {
    Storage::fake('shares');
    $this->service = app(ShareService::class);
});

test('create share without password stores encryption key', function () {
    $file = UploadedFile::fake()->create('document.pdf', 1024);

    $share = $this->service->createShare([
        ['file' => $file, 'relativePath' => null],
    ]);

    expect($share)->toBeInstanceOf(Share::class);
    expect($share->token)->toHaveLength(16);
    expect($share->password)->toBeNull();
    expect($share->encryption_key)->not->toBeNull();
    expect($share->wrapped_key)->toBeNull();
    expect($share->files)->toHaveCount(1);
    expect($share->files->first()->original_name)->toBe('document.pdf');
});

test('create share with password does not store encryption key', function () {
    $file = UploadedFile::fake()->create('secret.txt', 512);

    $share = $this->service->createShare([
        ['file' => $file, 'relativePath' => null],
    ], [
        'password' => 'my-password',
    ]);

    expect($share->password)->not->toBeNull();
    expect($share->encryption_key)->toBeNull();
    expect(Hash::check('my-password', $share->password))->toBeTrue();
});

test('create share with options sets expiration and max downloads', function () {
    $file = UploadedFile::fake()->create('file.txt', 256);

    $share = $this->service->createShare([
        ['file' => $file, 'relativePath' => null],
    ], [
        'expires_at' => now()->addDay(),
        'max_downloads' => 5,
    ]);

    expect($share->expires_at)->not->toBeNull();
    expect($share->max_downloads)->toBe(5);
});

test('create share with multiple files', function () {
    $file1 = UploadedFile::fake()->create('file1.txt', 100);
    $file2 = UploadedFile::fake()->create('file2.txt', 200);

    $share = $this->service->createShare([
        ['file' => $file1, 'relativePath' => 'folder/file1.txt'],
        ['file' => $file2, 'relativePath' => 'folder/file2.txt'],
    ]);

    expect($share->files)->toHaveCount(2);
    expect($share->files->first()->relative_path)->toBe('folder/file1.txt');
});

test('delete share removes files and database records', function () {
    $file = UploadedFile::fake()->create('file.txt', 100);

    $share = $this->service->createShare([
        ['file' => $file, 'relativePath' => null],
    ]);

    $shareId = $share->id;
    $token = $share->token;

    $this->service->deleteShare($share);

    expect(Share::query()->find($shareId))->toBeNull();
    expect(ShareFile::query()->where('share_id', $shareId)->count())->toBe(0);
    expect(Storage::disk('shares')->directories())->not->toContain($token);
});

test('verify password returns true for correct password', function () {
    $file = UploadedFile::fake()->create('file.txt', 100);

    $share = $this->service->createShare([
        ['file' => $file, 'relativePath' => null],
    ], [
        'password' => 'correct-password',
    ]);

    expect($this->service->verifyPassword($share, 'correct-password'))->toBeTrue();
    expect($this->service->verifyPassword($share, 'wrong-password'))->toBeFalse();
});

test('verify password returns true for non-password share', function () {
    $file = UploadedFile::fake()->create('file.txt', 100);

    $share = $this->service->createShare([
        ['file' => $file, 'relativePath' => null],
    ]);

    expect($this->service->verifyPassword($share, 'any'))->toBeTrue();
});

test('record download increments counter', function () {
    $share = Share::factory()->create(['download_count' => 0]);

    $this->service->recordDownload($share);

    expect($share->fresh()->download_count)->toBe(1);
});

test('record download auto-deletes when limit reached', function () {
    $share = Share::factory()->withMaxDownloads(1)->create(['download_count' => 0]);

    $this->service->recordDownload($share);

    expect(Share::query()->find($share->id))->toBeNull();
});

test('get total used space sums share sizes', function () {
    Share::factory()->create(['total_size' => 1000]);
    Share::factory()->create(['total_size' => 2000]);

    expect($this->service->getTotalUsedSpace())->toBe(3000);
});

test('is storage full checks against quota', function () {
    Setting::set('max_storage_quota', 1000);

    Share::factory()->create(['total_size' => 999]);
    expect($this->service->isStorageFull())->toBeFalse();

    Share::factory()->create(['total_size' => 1]);
    expect($this->service->isStorageFull())->toBeTrue();
});

test('get decryption key returns stored key for non-password share', function () {
    $file = UploadedFile::fake()->create('file.txt', 100);

    $share = $this->service->createShare([
        ['file' => $file, 'relativePath' => null],
    ]);

    $key = $this->service->getDecryptionKey($share);

    expect($key)->not->toBeNull();
    expect(strlen($key))->toBe(64);
});

test('get decryption key unwraps the data key of a password share, which decrypts its files', function () {
    $file = UploadedFile::fake()->createWithContent('file.txt', 'the secret contents');

    $share = $this->service->createShare([
        ['file' => $file, 'relativePath' => null],
    ], [
        'password' => 'test-password',
    ]);

    $key = $this->service->getDecryptionKey($share, 'test-password');

    $decrypted = implode('', iterator_to_array(app(FileEncryptionService::class)->decryptedChunks($this->service->storedFilePath($share->files->first()), $key), false));
    expect($decrypted)->toBe('the secret contents');
});

test('get decryption key derives the key of a password share created before key wrapping', function () {
    $salt = str_repeat('ab', 32);
    $share = Share::factory()->withPassword('old-password')->create(['encryption_salt' => $salt]);

    $key = $this->service->getDecryptionKey($share, 'old-password');

    expect($key)->toBe(hash_pbkdf2('sha256', 'old-password', hex2bin($salt), 100000, 64));
});

test('get decryption key throws for password share without password', function () {
    $file = UploadedFile::fake()->create('file.txt', 100);

    $share = $this->service->createShare([
        ['file' => $file, 'relativePath' => null],
    ], [
        'password' => 'test-password',
    ]);

    $this->service->getDecryptionKey($share);
})->throws(RuntimeException::class, 'Password required');

test('registering a file starts a pending share with the file\'s encrypted header on disk', function () {
    config(['uploads.chunk_size' => 4]);

    $file = $this->service->registerFile(null, 'report.pdf', 10, 'reports/report.pdf');

    expect($file->share->isCompleted())->toBeFalse();
    expect($file->share->total_size)->toBe(10);
    expect($file->relative_path)->toBe('reports/report.pdf');
    expect($file->completed_at)->toBeNull();
    expect(file_get_contents($this->service->storedFilePath($file), false, null, 0, 12))->toBe('SEALCHK2'.pack('N', 4));
});

test('a second registered file joins the same pending share and adds its size', function () {
    $first = $this->service->registerFile(null, 'one.txt', 10, null);

    $second = $this->service->registerFile($first->share, 'two.txt', 20, null);

    expect($second->share_id)->toBe($first->share_id);
    expect($second->share->total_size)->toBe(30);
});

test('a file larger than the admin file size limit is rejected', function () {
    Setting::set('max_file_size', 5 * 1024 * 1024);

    expect(fn () => $this->service->registerFile(null, 'big.iso', 6 * 1024 * 1024, null))
        ->toThrow(ValidationException::class, '"big.iso" is too large (6 MB). Maximum file size is 5 MB.');
    expect(Share::query()->count())->toBe(0);
});

test('a file beyond the admin limit of files per share is rejected', function () {
    Setting::set('max_files_per_share', 1);
    $first = $this->service->registerFile(null, 'one.txt', 10, null);

    expect(fn () => $this->service->registerFile($first->share, 'two.txt', 10, null))
        ->toThrow(ValidationException::class, 'Too many files. Maximum 1 files allowed per share.');
    expect(ShareFile::query()->count())->toBe(1);
});

test('a file that takes the share beyond the admin size per share is rejected', function () {
    Setting::set('max_size_per_share', 25);
    $first = $this->service->registerFile(null, 'one.txt', 20, null);

    expect(fn () => $this->service->registerFile($first->share, 'two.txt', 10, null))
        ->toThrow(ValidationException::class, 'Total file size exceeds the maximum allowed per share.');
});

test('a file that does not fit the storage quota beside files still uploading is rejected', function () {
    Setting::set('max_storage_quota', 100);
    Share::factory()->pending()->create(['total_size' => 60]);

    expect(fn () => $this->service->registerFile(null, 'file.txt', 50, null))
        ->toThrow(ValidationException::class, 'Storage is full. Please contact the administrator.');
});

test('chunks stored in order complete the file', function () {
    config(['uploads.chunk_size' => 4]);
    $file = $this->service->registerFile(null, 'notes.txt', 6, null);

    $afterFirst = $this->service->storeChunk($file, 0, encryptedChunk($file, 'abcd', 0, false));
    $afterLast = $this->service->storeChunk($file->refresh(), 1, encryptedChunk($file, 'ef', 1, true));

    expect([$afterFirst, $afterLast])->toBe([1, 2]);
    expect($file->refresh()->completed_at)->not->toBeNull();
    $decrypted = implode('', iterator_to_array(app(FileEncryptionService::class)->decryptedChunks($this->service->storedFilePath($file), $file->share->encryption_key), false));
    expect($decrypted)->toBe('abcdef');
});

test('a chunk stored a second time is counted once', function () {
    config(['uploads.chunk_size' => 4]);
    $file = $this->service->registerFile(null, 'notes.txt', 6, null);
    $chunk = encryptedChunk($file, 'abcd', 0, false);
    $this->service->storeChunk($file, 0, $chunk);

    $uploadedChunks = $this->service->storeChunk($file, 0, $chunk);

    expect($uploadedChunks)->toBe(1);
    expect($file->refresh()->uploaded_chunks)->toBe(1);
});

test('a chunk with the wrong length is rejected', function () {
    config(['uploads.chunk_size' => 4]);
    $file = $this->service->registerFile(null, 'notes.txt', 6, null);

    expect(fn () => $this->service->storeChunk($file, 0, encryptedChunk($file, 'abc', 0, false)))
        ->toThrow(InvalidArgumentException::class, 'wrong length');
    expect($file->refresh()->uploaded_chunks)->toBe(0);
});

test('a chunk that fails authentication is rejected', function () {
    config(['uploads.chunk_size' => 4]);
    $file = $this->service->registerFile(null, 'notes.txt', 6, null);
    $chunk = encryptedChunk($file, 'abcd', 0, false);
    $chunk[0] = $chunk[0] ^ "\x01";

    expect(fn () => $this->service->storeChunk($file, 0, $chunk))
        ->toThrow(InvalidArgumentException::class, 'failed authentication');
    expect($file->refresh()->uploaded_chunks)->toBe(0);
});

test('a chunk beyond the end of the file is rejected', function () {
    config(['uploads.chunk_size' => 4]);
    $file = $this->service->registerFile(null, 'notes.txt', 4, null);

    expect(fn () => $this->service->storeChunk($file, 1, encryptedChunk($file, 'abcd', 1, true)))
        ->toThrow(InvalidArgumentException::class, 'beyond the end');
});

test('the MIME type is detected from the first chunk\'s content', function () {
    $png = base64_decode('iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNkYPhfDwAChwGA60e6kgAAAABJRU5ErkJggg==');
    $file = $this->service->registerFile(null, 'photo.bin', strlen($png), null);

    $this->service->storeChunk($file, 0, encryptedChunk($file, $png, 0, true));

    expect($file->refresh()->mime_type)->toBe('image/png');
});

test('a chunk for a removed file is rejected', function () {
    $file = $this->service->registerFile(null, 'notes.txt', 4, null);
    $chunk = encryptedChunk($file, 'abcd', 0, true);
    $this->service->removeFile($file);

    $this->service->storeChunk($file, 0, $chunk);
})->throws(ModelNotFoundException::class);

test('removing a file deletes it and gives its size back', function () {
    $keep = $this->service->registerFile(null, 'keep.txt', 10, null);
    $remove = $this->service->registerFile($keep->share, 'remove.txt', 20, null);
    $path = $this->service->storedFilePath($remove);

    $this->service->removeFile($remove);

    expect($keep->share->refresh()->total_size)->toBe(10);
    expect(file_exists($path))->toBeFalse();
    $this->assertModelMissing($remove);
});

test('completing a share with a file still uploading is rejected', function () {
    $file = $this->service->registerFile(null, 'notes.txt', 4, null);

    expect(fn () => $this->service->completeShare($file->share))
        ->toThrow(ValidationException::class, 'Wait until every file has finished uploading, or remove the ones that failed.');
    expect($file->share->refresh()->isCompleted())->toBeFalse();
});

test('completing a share without files is rejected', function () {
    $share = Share::factory()->pending()->create();

    expect(fn () => $this->service->completeShare($share))
        ->toThrow(ValidationException::class, 'Please select at least one file to upload.');
});

test('completing a share with a password wraps its data key instead of storing it', function () {
    $file = $this->service->registerFile(null, 'notes.txt', 4, null);
    $this->service->storeChunk($file, 0, encryptedChunk($file, 'abcd', 0, true));
    $dataKey = $file->share->encryption_key;

    $share = $this->service->completeShare($file->share, ['password' => 'a-long-password']);

    expect($share->refresh()->isCompleted())->toBeTrue();
    expect($share->encryption_key)->toBeNull();
    expect(app(FileEncryptionService::class)->unwrapKey($share->wrapped_key, 'a-long-password'))->toBe($dataKey);
});

test('create share stores an empty file', function () {
    $share = $this->service->createShare([
        ['file' => UploadedFile::fake()->createWithContent('empty.txt', ''), 'relativePath' => null],
    ]);

    expect($share->files->first()->completed_at)->not->toBeNull();
    expect(filesize($this->service->storedFilePath($share->files->first())))->toBe(FileEncryptionService::HEADER_LENGTH + FileEncryptionService::TAG_LENGTH);
});