ICTS_2021/Unity3/Assets/AssetBundling/Editor/AssetBundleExporter.cs

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

/// <summary>
/// Exports the levels under ForAssetBundles asset folder.
/// The build target used is dependent on the current project's platform.
/// This is to avoid switching of platform causing pain for reimporting ALL assets (especially if using PVRTC on iOS)
/// </summary>
public class AssetBundleExporter
{
	public static void Export()
	{
		CreateAssetBundleFolders();

		CleanStreamingAssetsFolder();

		string forAssetBundlesPath = Application.dataPath + "/ForAssetBundles";
		//Find all levels to export
		System.IO.DirectoryInfo dir = new System.IO.DirectoryInfo(forAssetBundlesPath);
		foreach (System.IO.DirectoryInfo g in dir.GetDirectories())
		{
			BuildTarget buildTarget;
#if UNITY_IPHONE
			buildTarget = BuildTarget.iOS;
#elif UNITY_ANDROID
			buildTarget = BuildTarget.Android;
#elif UNITY_WEBPLAYER
			buildTarget = BuildTarget.WebPlayer;
#endif
			Export(g.Name, g.FullName, buildTarget);
		}
		CopyDefaultAssetBundleFor(AssetBundleUtils.GetBuildTargetPrefix());
	}

	static void Export(string bundleNamePrefix, string srcPath, BuildTarget buildTarget)
	{
		System.IO.DirectoryInfo dir = new System.IO.DirectoryInfo(srcPath);
		//find all sub-parts to export
		foreach (System.IO.DirectoryInfo subPart in dir.GetDirectories())
		{
			string bundleName = bundleNamePrefix + "_" + subPart.Name;
			AVDebug.Log("Building bundle " + bundleName);

			List<Object> assets = new List<Object>();
			foreach (System.IO.FileInfo file in subPart.GetFiles())
			{
				//skip meta files
				if (file.Name.EndsWith("meta"))
				{
					continue;
				}
				string relativeSrcPath = "Assets"+file.FullName.Substring(Application.dataPath.Length);
				AVDebug.Log("Adding "+relativeSrcPath);
				Object[] asset = AssetDatabase.LoadAllAssetsAtPath(relativeSrcPath);
				assets.AddRange(asset);
			}
			Debug.Log("assets "+assets.Count);

			string destPath = GetDestPathFor(buildTarget) + "/"+bundleName+".unity3d";
			BuildPipeline.BuildAssetBundle(assets[0], assets.ToArray(), destPath, BuildAssetBundleOptions.CompleteAssets | BuildAssetBundleOptions.CollectDependencies, buildTarget);
		}
	}

	static string GetDestPathFor(BuildTarget buildTarget)
	{
		string result = AssetBundleUtils.GetLocalAssetBundlesDestPath() + buildTarget.ToString();
		AVDebug.Log("Destination is " + result);
		return result;
	}


	static void CreateAssetBundleFolders()
	{
		string assetBundlesPath = AssetBundleUtils.GetLocalAssetBundlesDestPath();
		System.IO.DirectoryInfo dir = new System.IO.DirectoryInfo(assetBundlesPath);
		if (dir.Exists)
		{
			return;
		}
		dir.Create();

		dir = new System.IO.DirectoryInfo(assetBundlesPath + BuildTarget.iOS.ToString());
		dir.Create();
		dir = new System.IO.DirectoryInfo(assetBundlesPath + BuildTarget.Android.ToString());
		dir.Create();
	}

	static void CleanStreamingAssetsFolder()
	{
		string path = Directory.GetCurrentDirectory()+"/Assets/StreamingAssets";
		System.IO.DirectoryInfo streamingAssetsFolder = new DirectoryInfo(path);

		foreach (FileInfo file in streamingAssetsFolder.GetFiles())
		{
		    file.Delete();
		}
		foreach (DirectoryInfo dir in streamingAssetsFolder.GetDirectories())
		{
		    dir.Delete(true);
		}
	}

	static void CopyDefaultAssetBundleFor(string platform)
	{
		string streamingAssetsFolderPath = Directory.GetCurrentDirectory()+"/Assets/StreamingAssets/"+platform;
		Directory.CreateDirectory(streamingAssetsFolderPath);

		string assetBundlesPath = Directory.GetCurrentDirectory()+"/AssetBundles/"+platform;
		System.IO.DirectoryInfo assetBundlesFolder = new DirectoryInfo(assetBundlesPath);

		foreach (FileInfo file in assetBundlesFolder.GetFiles())
		{
			if (file.Name.StartsWith("default_"))
			{
		    	file.CopyTo(streamingAssetsFolderPath+"/"+file.Name);
			}
		}
	}

}