// ==========================================================================
//  Squidex Headless CMS
// ==========================================================================
//  Copyright (c) Squidex UG (haftungsbeschraenkt)
//  All rights reserved. Licensed under the MIT license.
// ==========================================================================

using System.Security.Claims;
using System.Text;
using FakeItEasy;
using Microsoft.Extensions.Caching.Memory;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Options;
using Squidex.Assets;
using Squidex.Domain.Apps.Core.Assets;
using Squidex.Domain.Apps.Core.Contents;
using Squidex.Domain.Apps.Core.Rules.EnrichedEvents;
using Squidex.Domain.Apps.Core.Scripting;
using Squidex.Domain.Apps.Core.TestHelpers;
using Squidex.Domain.Apps.Entities.TestHelpers;
using Squidex.Infrastructure;
using Squidex.Infrastructure.Json.Objects;
using Xunit;

namespace Squidex.Domain.Apps.Entities.Assets
{
    public class AssetsJintExtensionTests : IClassFixture<TranslationsFixture>
    {
        private readonly IAppProvider appProvider = A.Fake<IAppProvider>();
        private readonly IAssetFileStore assetFileStore = A.Fake<IAssetFileStore>();
        private readonly IAssetQueryService assetQuery = A.Fake<IAssetQueryService>();
        private readonly IAssetThumbnailGenerator assetThumbnailGenerator = A.Fake<IAssetThumbnailGenerator>();
        private readonly NamedId<DomainId> appId = NamedId.Of(DomainId.NewGuid(), "my-app");
        private readonly JintScriptEngine sut;

        public AssetsJintExtensionTests()
        {
            var services =
                new ServiceCollection()
                    .AddSingleton(appProvider)
                    .AddSingleton(assetFileStore)
                    .AddSingleton(assetQuery)
                    .AddSingleton(assetThumbnailGenerator)
                    .BuildServiceProvider();

            var extensions = new IJintExtension[]
            {
                new AssetsJintExtension(services)
            };

            A.CallTo(() => appProvider.GetAppAsync(appId.Id, false, A<CancellationToken>._))
                .Returns(Mocks.App(appId));

            sut = new JintScriptEngine(new MemoryCache(Options.Create(new MemoryCacheOptions())),
                Options.Create(new JintScriptOptions
                {
                    TimeoutScript = TimeSpan.FromSeconds(2),
                    TimeoutExecution = TimeSpan.FromSeconds(10)
                }),
                extensions);
        }

        public static IEnumerable<object[]> Encodings()
        {
            yield return new object[] { "ascii" };
            yield return new object[] { "unicode" };
            yield return new object[] { "utf8" };
            yield return new object[] { "base64" };
        }

        public static byte[] Encode(string encoding, string text)
        {
            switch (encoding)
            {
                case "base64":
                    return Convert.FromBase64String(text);
                case "ascii":
                    return Encoding.ASCII.GetBytes(text);
                case "unicode":
                    return Encoding.Unicode.GetBytes(text);
                default:
                    return Encoding.UTF8.GetBytes(text);
            }
        }

        [Fact]
        public async Task Should_resolve_asset()
        {
            var (vars, assets) = SetupAssetsVars(1);

            var expected = $@"
                Text: {assets[0].FileName} {assets[0].Id}
            ";

            var script = @"
                getAsset(data.assets.iv[0], function (assets) {
                    var result1 = `Text: ${assets[0].fileName} ${assets[0].id}`;

                    complete(`${result1}`);
                });";

            var result = (await sut.ExecuteAsync(vars, script)).ToString();

            Assert.Equal(Cleanup(expected), Cleanup(result));
        }

        [Fact]
        public async Task Should_resolve_assets()
        {
            var (vars, assets) = SetupAssetsVars(2);

            var expected = $@"
                Text: {assets[0].FileName} {assets[0].Id}
                Text: {assets[1].FileName} {assets[1].Id}
            ";

            var script = @"
                getAssets(data.assets.iv, function (assets) {
                    var result1 = `Text: ${assets[0].fileName} ${assets[0].id}`;
                    var result2 = `Text: ${assets[1].fileName} ${assets[1].id}`;

                    complete(`${result1}\n${result2}`);
                });";

            var result = (await sut.ExecuteAsync(vars, script)).ToString();

            Assert.Equal(Cleanup(expected), Cleanup(result));
        }

        [Theory]
        [MemberData(nameof(Encodings))]
        public async Task Should_resolve_text(string encoding)
        {
            var (vars, assets) = SetupAssetsVars(1);

            SetupText(assets[0].ToRef(), Encode(encoding, "hello+assets"));

            var expected = @"
                Text: hello+assets
            ";

            var script = $@"
                getAssets(data.assets.iv, function (assets) {{
                    getAssetText(assets[0], function (text) {{
                        var result = `Text: ${{text}}`;

                        complete(result);
                    }}, '{encoding}');
                }});";

            var result = (await sut.ExecuteAsync(vars, script)).ToString();

            Assert.Equal(Cleanup(expected), Cleanup(result));
        }

        [Fact]
        public async Task Should_not_resolve_text_if_too_big()
        {
            var (vars, _) = SetupAssetsVars(1, 1_000_000);

            var expected = @"
                Text: ErrorTooBig
            ";

            var script = @"
                getAssets(data.assets.iv, function (assets) {
                    getAssetText(assets[0], function (text) {
                        var result = `Text: ${text}`;

                        complete(result);
                    });
                });";

            var result = (await sut.ExecuteAsync(vars, script)).ToString();

            Assert.Equal(Cleanup(expected), Cleanup(result));

            A.CallTo(() => assetFileStore.DownloadAsync(A<DomainId>._, A<DomainId>._, A<long>._, null, A<Stream>._, A<BytesRange>._, A<CancellationToken>._))
                .MustNotHaveHappened();
        }

        [Theory]
        [MemberData(nameof(Encodings))]
        public async Task Should_resolve_text_from_event(string encoding)
        {
            var @event = new EnrichedAssetEvent
            {
                Id = DomainId.NewGuid(),
                FileVersion = 0,
                FileSize = 100,
                AppId = appId
            };

            SetupText(@event.ToRef(), Encode(encoding, "hello+assets"));

            var vars = new ScriptVars
            {
                ["event"] = @event
            };

            var expected = @"
                Text: hello+assets
            ";

            var script = $@"
                getAssetText(event, function (text) {{
                    var result = `Text: ${{text}}`;

                    complete(result);
                }}, '{encoding}');";

            var result = (await sut.ExecuteAsync(vars, script)).ToString();

            Assert.Equal(Cleanup(expected), Cleanup(result));
        }

        [Fact]
        public async Task Should_resolve_blur_hash()
        {
            var (vars, assets) = SetupAssetsVars(1);

            SetupBlurHash(assets[0].ToRef(), "Hash");

            var expected = @"
                Hash: Hash
            ";

            var script = @"
                getAssets(data.assets.iv, function (assets) {
                    getAssetBlurHash(assets[0], function (text) {
                        var result = `Hash: ${text}`;

                        complete(result);
                    });
                });";

            var result = (await sut.ExecuteAsync(vars, script)).ToString();

            Assert.Equal(Cleanup(expected), Cleanup(result));
        }

        [Fact]
        public async Task Should_not_resolve_blur_hash_if_too_big()
        {
            var (vars, assets) = SetupAssetsVars(1, 1_000_000);

            SetupBlurHash(assets[0].ToRef(), "Hash");

            var expected = @"
                Hash: null
            ";

            var script = @"
                getAssets(data.assets.iv, function (assets) {
                    getAssetBlurHash(assets[0], function (text) {
                        var result = `Hash: ${text}`;

                        complete(result);
                    });
                });";

            var result = (await sut.ExecuteAsync(vars, script)).ToString();

            Assert.Equal(Cleanup(expected), Cleanup(result));
        }

        [Fact]
        public async Task Should_not_resolve_blue_hash_if_not_an_image()
        {
            var (vars, assets) = SetupAssetsVars(1, type: AssetType.Audio);

            SetupBlurHash(assets[0].ToRef(), "Hash");

            var expected = @"
                Hash: null
            ";

            var script = @"
                getAssets(data.assets.iv, function (assets) {
                    getAssetBlurHash(assets[0], function (text) {
                        var result = `Hash: ${text}`;

                        complete(result);
                    });
                });";

            var result = (await sut.ExecuteAsync(vars, script)).ToString();

            Assert.Equal(Cleanup(expected), Cleanup(result));
        }

        [Fact]
        public async Task Should_resolve_blur_hash_from_event()
        {
            var @event = new EnrichedAssetEvent
            {
                Id = DomainId.NewGuid(),
                AssetType = AssetType.Image,
                FileVersion = 0,
                FileSize = 100,
                AppId = appId
            };

            SetupBlurHash(@event.ToRef(), "Hash");

            var vars = new ScriptVars
            {
                ["event"] = @event
            };

            var expected = @"
                Text: Hash
            ";

            var script = @"
                getAssetBlurHash(event, function (text) {
                    var result = `Text: ${text}`;

                    complete(result);
                });";

            var result = (await sut.ExecuteAsync(vars, script)).ToString();

            Assert.Equal(Cleanup(expected), Cleanup(result));
        }

        private void SetupBlurHash(AssetRef asset, string hash)
        {
            A.CallTo(() => assetThumbnailGenerator.ComputeBlurHashAsync(A<Stream>._, asset.MimeType, A<BlurOptions>._, A<CancellationToken>._))
                .Returns(hash);
        }

        private void SetupText(AssetRef asset, byte[] bytes)
        {
            A.CallTo(() => assetFileStore.DownloadAsync(appId.Id, asset.Id, asset.FileVersion, null, A<Stream>._, A<BytesRange>._, A<CancellationToken>._))
                .Invokes(x => x.GetArgument<Stream>(4)?.Write(bytes));
        }

        private (ScriptVars, IAssetEntity[]) SetupAssetsVars(int count, int fileSize = 100, AssetType type = AssetType.Image)
        {
            var assets = Enumerable.Range(0, count).Select(x => CreateAsset(1, fileSize, type)).ToArray();
            var assetIds = assets.Select(x => x.Id);

            var user = new ClaimsPrincipal();

            var data =
                new ContentData()
                    .AddField("assets",
                        new ContentFieldData()
                            .AddInvariant(JsonValue.Array(assetIds)));

            A.CallTo(() => assetQuery.QueryAsync(
                    A<Context>.That.Matches(x => x.App.Id == appId.Id && x.User == user), null, A<Q>.That.HasIds(assetIds), A<CancellationToken>._))
                .Returns(ResultList.CreateFrom(2, assets));

            var vars = new ScriptVars
            {
                ["data"] = data,
                ["appId"] = appId.Id,
                ["appName"] = appId.Name,
                ["user"] = user
            };

            return (vars, assets);
        }

        private IEnrichedAssetEntity CreateAsset(int index, int fileSize = 100, AssetType type = AssetType.Image)
        {
            return new AssetEntity
            {
                AppId = appId,
                Id = DomainId.NewGuid(),
                FileSize = fileSize,
                FileName = $"file{index}.jpg",
                MimeType = "image/jpg",
                Type = type
            };
        }

        private static string Cleanup(string text)
        {
            return text
                .Replace("\r", string.Empty, StringComparison.Ordinal)
                .Replace("\n", string.Empty, StringComparison.Ordinal)
                .Replace(" ", string.Empty, StringComparison.Ordinal);
        }
    }
}