using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using Moq;
using PowderCoating.Application.Configuration;
using PowderCoating.Application.Interfaces;
using PowderCoating.Application.Services;

namespace PowderCoating.UnitTests;

public class StorageMigrationServiceTests
{
    [Fact]
    public async Task MigrateFilesystemToAzureAsync_ReturnsError_WhenDirectoryMissing()
    {
        var service = CreateService();
        var missingPath = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString("N"));

        var result = await service.MigrateFilesystemToAzureAsync(missingPath);

        Assert.Equal(0, result.Failed);
        Assert.Equal(0, result.Total);
        Assert.Contains("Media directory not found", result.Errors.Single());
        Assert.True(result.HasErrors);
    }

    [Fact]
    public async Task MigrateFilesystemToAzureAsync_MarksUnknownPathsAsFailed()
    {
        var mediaRoot = CreateTempMediaRoot();
        try
        {
            var unknownPath = Path.Combine(mediaRoot, "1", "misc");
            Directory.CreateDirectory(unknownPath);
            await File.WriteAllTextAsync(Path.Combine(unknownPath, "file.bin"), "abc");

            var service = CreateService();

            var result = await service.MigrateFilesystemToAzureAsync(mediaRoot);

            Assert.Equal(1, result.Failed);
            Assert.Contains(result.Errors, e => e.Contains("Unknown file type"));
            Assert.Equal(MigrationFileStatus.Failed, result.Files.Single().Status);
        }
        finally
        {
            SafeDeleteDirectory(mediaRoot);
        }
    }

    [Fact]
    public async Task MigrateFilesystemToAzureAsync_SkipsExistingBlobs()
    {
        var mediaRoot = CreateTempMediaRoot();
        try
        {
            var filePath = WriteMediaFile(mediaRoot, "1/profile-photos/user.jpg", "profile");
            var relativePath = "1/profile-photos/user.jpg";

            var blobService = new Mock<IAzureBlobStorageService>();
            blobService
                .Setup(x => x.ExistsAsync("profileimages", relativePath))
                .ReturnsAsync(true);

            var service = CreateService(blobService);

            var result = await service.MigrateFilesystemToAzureAsync(mediaRoot);

            Assert.Equal(1, result.Skipped);
            Assert.Equal(0, result.Migrated);
            Assert.Equal(MigrationFileStatus.Skipped, result.Files.Single().Status);
            Assert.True(File.Exists(filePath));
        }
        finally
        {
            SafeDeleteDirectory(mediaRoot);
        }
    }

    [Fact]
    public async Task MigrateFilesystemToAzureAsync_RecordsUploadFailures()
    {
        var mediaRoot = CreateTempMediaRoot();
        try
        {
            WriteMediaFile(mediaRoot, "1/job-photos/9/photo.png", "photo");
            const string relativePath = "1/job-photos/9/photo.png";

            var blobService = new Mock<IAzureBlobStorageService>();
            blobService.Setup(x => x.ExistsAsync("jobimages", relativePath)).ReturnsAsync(false);
            blobService
                .Setup(x => x.UploadAsync("jobimages", relativePath, It.IsAny<Stream>(), "image/png"))
                .ReturnsAsync((false, "upload failed"));

            var service = CreateService(blobService);

            var result = await service.MigrateFilesystemToAzureAsync(mediaRoot);

            Assert.Equal(1, result.Failed);
            Assert.Contains(result.Errors, e => e.Contains("upload failed"));
            Assert.Equal(MigrationFileStatus.Failed, result.Files.Single().Status);
        }
        finally
        {
            SafeDeleteDirectory(mediaRoot);
        }
    }

    [Fact]
    public async Task MigrateFilesystemToAzureAsync_DeletesLocalFileAfterSuccessfulMigration_WhenRequested()
    {
        var mediaRoot = CreateTempMediaRoot();
        try
        {
            var fullPath = WriteMediaFile(mediaRoot, "1/company-logo.png", "logo");
            const string relativePath = "1/company-logo.png";

            var blobService = new Mock<IAzureBlobStorageService>();
            blobService.Setup(x => x.ExistsAsync("companylogos", relativePath)).ReturnsAsync(false);
            blobService
                .Setup(x => x.UploadAsync("companylogos", relativePath, It.IsAny<Stream>(), "image/png"))
                .ReturnsAsync((true, string.Empty));

            var service = CreateService(blobService);

            var result = await service.MigrateFilesystemToAzureAsync(mediaRoot, deleteLocalAfterMigration: true);

            Assert.Equal(1, result.Migrated);
            Assert.Contains(result.Files, f => f.RelativePath == relativePath && f.Status == MigrationFileStatus.Migrated);
            Assert.False(File.Exists(fullPath));
        }
        finally
        {
            SafeDeleteDirectory(mediaRoot);
        }
    }

    [Fact]
    public async Task MigrateFilesystemToAzureAsync_ContinuesAfterPerFileException()
    {
        var mediaRoot = CreateTempMediaRoot();
        try
        {
            WriteMediaFile(mediaRoot, "1/profile-photos/user.jpg", "profile");
            WriteMediaFile(mediaRoot, "1/equipment-manuals/manual.pdf", "manual");

            var blobService = new Mock<IAzureBlobStorageService>();
            blobService
                .Setup(x => x.ExistsAsync("profileimages", "1/profile-photos/user.jpg"))
                .ThrowsAsync(new InvalidOperationException("broken exists"));
            blobService
                .Setup(x => x.ExistsAsync("manuals", "1/equipment-manuals/manual.pdf"))
                .ReturnsAsync(false);
            blobService
                .Setup(x => x.UploadAsync("manuals", "1/equipment-manuals/manual.pdf", It.IsAny<Stream>(), "application/pdf"))
                .ReturnsAsync((true, string.Empty));

            var service = CreateService(blobService);

            var result = await service.MigrateFilesystemToAzureAsync(mediaRoot);

            Assert.Equal(1, result.Failed);
            Assert.Equal(1, result.Migrated);
            Assert.Contains(result.Errors, e => e.Contains("broken exists"));
            Assert.Equal(2, result.Total);
        }
        finally
        {
            SafeDeleteDirectory(mediaRoot);
        }
    }

    private static StorageMigrationService CreateService(Mock<IAzureBlobStorageService>? blobService = null)
    {
        var settings = Options.Create(new StorageSettings
        {
            Containers = new StorageContainers
            {
                ProfileImages = "profileimages",
                JobImages = "jobimages",
                Manuals = "manuals",
                CompanyLogos = "companylogos"
            }
        });

        return new StorageMigrationService(
            (blobService ?? new Mock<IAzureBlobStorageService>()).Object,
            settings,
            Mock.Of<ILogger<StorageMigrationService>>());
    }

    private static string CreateTempMediaRoot()
    {
        var path = Path.Combine(Path.GetTempPath(), "pca-tests", Guid.NewGuid().ToString("N"));
        Directory.CreateDirectory(path);
        return path;
    }

    private static string WriteMediaFile(string mediaRoot, string relativePath, string content)
    {
        var fullPath = Path.Combine(mediaRoot, relativePath.Replace("/", Path.DirectorySeparatorChar.ToString()));
        Directory.CreateDirectory(Path.GetDirectoryName(fullPath)!);
        File.WriteAllText(fullPath, content);
        return fullPath;
    }

    private static void SafeDeleteDirectory(string path)
    {
        if (Directory.Exists(path))
        {
            Directory.Delete(path, recursive: true);
        }
    }
}