using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEditor;
using System.IO;

public class AssetBundleBuildExtersion
{
    public static void Build(string _output, string _category, BuildAssetBundleOptions _bundleOption, BuildTarget _buildTarget)
    {
        var assetBundles = AssetDatabase.GetAllAssetBundleNames();

        List<string> targetAssetBundles = new List<string>();
        for (int i = 0; i < assetBundles.Length; i++)
        {
            var bundleName = assetBundles[i];
            if (bundleName.StartsWith(_category))
            {
                targetAssetBundles.Add(bundleName);
            }
        }

        var assets = new List<AssetBundleBuild>();

        for (int i = 0; i < targetAssetBundles.Count; i++)
        {
            var assetBundleBuild = new AssetBundleBuild();
            assetBundleBuild.assetBundleName = targetAssetBundles[i];
            assetBundleBuild.assetNames = AssetDatabase.GetAssetPathsFromAssetBundle(targetAssetBundles[i]);
            assets.Add(assetBundleBuild);
        }

        var rootPath = StringUtility.Contact(_output, Path.AltDirectorySeparatorChar, _category);
        var mainFile = StringUtility.Contact(_output, Path.AltDirectorySeparatorChar, GetMainFestFileName(_buildTarget));
        var mainFileRename = StringUtility.Contact(_output, Path.AltDirectorySeparatorChar, _category, "_assetbundle");
        var manifest = StringUtility.Contact(_output, Path.AltDirectorySeparatorChar, GetMainFestFileName(_buildTarget), ".manifest");
        var manifestRename = StringUtility.Contact(_output, Path.AltDirectorySeparatorChar, _category, "_assetbundle.manifest");

        if (Directory.Exists(rootPath))
        {
            Directory.Delete(rootPath, true);
        }

        Directory.CreateDirectory(rootPath);

        if (File.Exists(mainFileRename))
        {
            File.Delete(mainFileRename);
        }

        if (File.Exists(manifestRename))
        {
            File.Delete(manifestRename);
        }

        BuildPipeline.BuildAssetBundles(_output, assets.ToArray(), _bundleOption, _buildTarget);

        File.Move(mainFile, mainFileRename);
        File.Move(manifest, manifestRename);

    }

    static string GetMainFestFileName(BuildTarget _target)
    {
        switch (_target)
        {
            case BuildTarget.StandaloneWindows:
                return "standalone";
            case BuildTarget.Android:
                return "android";
            case BuildTarget.iOS:
                return "ios";
            default:
                return string.Empty;
        }
    }

}