// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using System.Collections.Generic;
using System.IO;
using System.Reflection;

namespace Microsoft.DotNet.Build.Tasks.Workloads;

internal class EmbeddedTemplates
{
    private static readonly Dictionary<string, string> s_templateResources = new();

    /// <summary>
    /// Extracts the specified filename from the embedded template resource into the destination folder and
    /// returns the full path of the file.
    /// </summary>
    /// <param name="filename">The name of the template file to extract.</param>
    /// <param name="destinationFolder">The directory where the file will be extracted.</param>
    /// <returns>The full path of the extracted file.</returns>
    public static string Extract(string filename, string destinationFolder)
    {
        return Extract(filename, destinationFolder, filename);
    }

    /// <summary>
    /// Extracts the specified filename from the embedded template resource into the destination folder using
    /// the specified filename and return the full path of the file.
    /// </summary>
    /// <param name="filename">The name of the template file to extract.</param>
    /// <param name="destinationFolder">The directory where the file will be extracted.</param>
    /// <returns>The full path of the extracted file.</returns>
    public static string Extract(string filename, string destinationFolder, string destinationFilename)
    {
        if (!s_templateResources.TryGetValue(filename, out string resourceName))
        {
            throw new KeyNotFoundException(string.Format(Strings.TemplateNotFound, filename));
        }

        // Clean out stale files just to be safe.
        string destinationPath = Path.Combine(destinationFolder, destinationFilename);
        if (File.Exists(destinationPath))
        {
            File.Delete(destinationPath);
        }
        else
        {
            Directory.CreateDirectory(destinationFolder);
        }

        using Stream rs = Assembly.GetExecutingAssembly().GetManifestResourceStream(resourceName);
        using FileStream fs = new(destinationPath, FileMode.Create, FileAccess.Write);

        if (rs == null)
        {
            throw new IOException(string.Format(Strings.TemplateResourceNotFound, resourceName));
        }

        rs.CopyTo(fs);

        return destinationPath;
    }

    static EmbeddedTemplates()
    {
        string ns = MethodBase.GetCurrentMethod().DeclaringType.Namespace;

        s_templateResources = new()
        {
            { "DependencyProvider.wxs", $"{ns}.MsiTemplate.DependencyProvider.wxs" },
            { "Directories.wxs", $"{ns}.MsiTemplate.Directories.wxs" },
            { "dotnethome_x64.wxs", $"{ns}.MsiTemplate.dotnethome_x64.wxs" },
            { "ManifestProduct.wxs", $"{ns}.MsiTemplate.ManifestProduct.wxs" },
            { "WorkloadSetProduct.wxs", $"{ns}.MsiTemplate.WorkloadSetProduct.wxs" },
            { "Product.wxs", $"{ns}.MsiTemplate.Product.wxs" },
            { "Productv5.wxs", $"{ns}.MsiTemplate.Productv5.wxs" },
            { "Registry.wxs", $"{ns}.MsiTemplate.Registry.wxs" },
            { "Variables.wxi", $"{ns}.MsiTemplate.Variables.wxi" },

            { $"msi.swr", $"{ns}.SwixTemplate.msi.swr" },
            { $"msi.swixproj", $"{ns}.SwixTemplate.msi.swixproj" },
            { $"component.swr", $"{ns}.SwixTemplate.component.swr" },
            { $"component.res.swr", $"{ns}.SwixTemplate.component.res.swr" },
            { $"component.swixproj", $"{ns}.SwixTemplate.component.swixproj" },
            { $"manifest.vsmanproj", $"{ns}.SwixTemplate.manifest.vsmanproj" },
            { $"packageGroup.swr", $"{ns}.SwixTemplate.packageGroup.swr" },
            { $"packageGroup.swixproj", $"{ns}.SwixTemplate.packageGroup.swixproj" },

            { "Icon.png", $"{ns}.Misc.Icon.png" },
            { "LICENSE.TXT", $"{ns}.Misc.LICENSE.TXT" },
            { "msi.csproj", $"{ns}.Misc.msi.csproj" }
        };
    }
}