package me.tvhee.tvheeapi.repositoryinstaller;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.lang.management.ManagementFactory;
import java.lang.reflect.Array;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.channels.Channels;
import java.nio.channels.ReadableByteChannel;
import java.nio.file.Files;
import java.util.Arrays;
import java.util.Enumeration;
import java.util.LinkedList;
import java.util.List;
import java.util.function.Predicate;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

public class Builder
{
	public static final boolean IS_WINDOWS = System.getProperty("os.name").startsWith("Windows");
	public static final File CWD = new File(".");
	private static File msysDir;
	private static File maven;

	public static void start() throws Exception
	{
		System.out.println("Java Version: " + JavaVersion.getCurrentVersion());
		System.out.println("Current Path: " + CWD.getAbsolutePath());
		if(CWD.getAbsolutePath().contains("'") || CWD.getAbsolutePath().contains("#") || CWD.getAbsolutePath().contains("~") || CWD.getAbsolutePath().contains("(") || CWD.getAbsolutePath().contains(")"))
		{
			System.err.println("Please do not run in a path with special characters!");
			return;
		}
		if(CWD.getAbsolutePath().contains("Dropbox") || CWD.getAbsolutePath().contains("OneDrive"))
		{
			System.err.println("Please do not run in a Dropbox, OneDrive, or similar. You can always copy the completed jars there later.");
			return;
		}

		try
		{
			runProcess(CWD, "sh", "-c", "exit");
		}
		catch(Exception ex)
		{
			if(Builder.IS_WINDOWS)
			{
				final String gitVersion = "PortableGit-2.30.0-" + (System.getProperty("os.arch").endsWith("64") ? "64" : "32") + "-bit";
				msysDir = new File(gitVersion, "PortableGit");
				if(!msysDir.isDirectory())
				{
					System.out.println("*** Could not find PortableGit installation, downloading. ***");
					final String gitName = gitVersion + ".7z.exe";
					final File gitInstall = new File(gitVersion, gitName);
					gitInstall.deleteOnExit();
					gitInstall.getParentFile().mkdirs();
					if(!gitInstall.exists())
					{
						download("https://github.com/git-for-windows/git/releases/download/v2.30.0.windows.1/" + gitName, gitInstall);
					}
					System.out.println("Extracting downloaded git install");
					runProcess(gitInstall.getParentFile(), gitInstall.getAbsolutePath(), "-y", "-gm2", "-nr");
					gitInstall.delete();
				}
				System.out.println("*** Using downloaded git " + msysDir + " ***");
				System.out.println("*** Please note that this is a beta feature, so if it does not work please also try a manual install of git from https://git-for-windows.github.io/ ***");
			}
			else
			{
				System.out.println("You must run this jar through bash (msysgit)");
				System.exit(1);
			}
		}
		try
		{
			runProcess(CWD, "git", "--version");
		}
		catch(Exception ex)
		{
			System.out.println("Could not successfully run git. Please ensure it is installed and functioning. " + ex.getMessage());
			System.exit(1);
		}
		try
		{
			runProcess(CWD, "git", "config", "--global", "--includes", "user.name");
		}
		catch(Exception ex)
		{
			System.out.println("Git name not set, setting it to default value.");
			runProcess(CWD, "git", "config", "--global", "user.name", "BuildTools");
		}
		try
		{
			runProcess(CWD, "git", "config", "--global", "--includes", "user.email");
		}
		catch(Exception ex)
		{
			System.out.println("Git email not set, setting it to default value.");
			runProcess(CWD, "git", "config", "--global", "user.email", "example@mail.com");
		}

		final String mavenVersion = "apache-maven-3.6.0";

		final String m2Home = System.getenv("M2_HOME");
		if(m2Home == null || !(maven = new File(m2Home)).exists())
		{
			maven = new File(mavenVersion);
			if(!maven.exists())
			{
				System.out.println("Maven does not exist, downloading. Please wait.");
				final File mvnTemp = new File(mavenVersion + "-bin.zip");
				mvnTemp.deleteOnExit();
				download("https://static.spigotmc.org/maven/" + mvnTemp.getName(), mvnTemp);
				unzip(mvnTemp, new File("."));
				mvnTemp.delete();
			}
		}

		String version = getNewestVersion();

		final File download = new File("TvheeAPI-" + version + ".jar");
		int resourceId = 85346;

		download("https://api.spigotmc.org/legacy/update.php?resource=" + resourceId, download);

		//runProcess(new File("C:\\Users\\<>\\IdeaProjects\\TvheeAPIRepositoryInstaller\\test\\apache-maven-3.6.0\\bin\\mvn.cmd"), "install:install-file", "-Dfile=\"" + download.getAbsolutePath() + "\"", "-DgroupId=me.tvhee", "-DartifactId=TvheeAPI", "-Dversion=" + version, "-Dpackaging=jar");
		runMaven(CWD, "install:install-file", "-Dfile=\"" + download.getAbsolutePath() + "\"", "-DgroupId=me.tvhee", "-DartifactId=TvheeAPI", "-Dversion=" + version, "-Dpackaging=jar");
	}

	private static String getNewestVersion()
	{
		try
		{
			int resourceId = 85346;

			HttpURLConnection connection = (HttpURLConnection) new URL("https://api.spigotmc.org/legacy/update.php?resource=" + resourceId).openConnection();
			connection.setRequestMethod("GET");

			final BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
			return reader.readLine();
		}
		catch(final Exception ex)
		{
			System.out.println("Could not check for update from SpigotMC.org" + ex.getMessage());
			return "";
		}
	}

	public static int runMaven(final File workDir, final String... command) throws Exception
	{
		final List<String> args = new LinkedList<>();

		if(Builder.IS_WINDOWS)
		{
			args.add("\"" + Builder.maven.getAbsolutePath() + "\\bin\\mvn.cmd\"");
		}
		else
		{
			args.add("sh");
			args.add("\"" + Builder.maven.getAbsolutePath() + "\\bin\\mvn\"");
		}

		args.add("-Dbt.name=dev");

		args.addAll(Arrays.asList(command));
		return runProcess(workDir, args.toArray(new String[args.size()]));
	}

	public static int runProcess(final File workDir, String... command) throws Exception
	{
		if(command[0].equals("java"))
		{
			command[0] = System.getProperty("java.home") + "/bin/" + command[0];
		}

		if(msysDir != null)
		{
			if("bash".equals(command[0]))
			{
				command[0] = "git-bash";
			}
			String cmd = System.getenv("ComSpec");
			if(cmd == null)
			{
				cmd = "cmd.exe";
			}
			final String[] shim = { cmd, "/D", "/C" };
			command = concat(shim, command, String.class);
		}
		return runProcess0(workDir, command);
	}

	public static <T> T[] concat(final T[] first, final T[] second, final Class<T> type)
	{
		final T[] result = newArray(type, first.length + second.length);
		System.arraycopy(first, 0, result, 0, first.length);
		System.arraycopy(second, 0, result, first.length, second.length);
		return result;
	}

	public static <T> T[] newArray(final Class<T> type, final int length)
	{
		return (T[]) Array.newInstance(type, length);
	}

	private static int runProcess0(final File workDir, final String... command) throws Exception
	{
		if(workDir == null)
			throw new NullPointerException();

		if(command == null || command.length < 1)
			throw new NullPointerException("Invalid command");

		final ProcessBuilder pb = new ProcessBuilder(command);
		pb.directory(workDir);
		pb.environment().put("JAVA_HOME", System.getProperty("java.home"));
		pb.environment().remove("M2_HOME");
		if(!pb.environment().containsKey("MAVEN_OPTS"))
		{
			pb.environment().put("MAVEN_OPTS", "-Xmx1024M");
		}
		if(!pb.environment().containsKey("_JAVA_OPTIONS"))
		{
			StringBuilder javaOptions = new StringBuilder("-Djdk.net.URLClassPath.disableClassPathURLCheck=true");
			for(final String arg : ManagementFactory.getRuntimeMXBean().getInputArguments())
			{
				if(arg.startsWith("-Xmx"))
				{
					javaOptions.append(" ").append(arg);
				}
			}
			pb.environment().put("_JAVA_OPTIONS", javaOptions.toString());
		}
		if(Builder.IS_WINDOWS)
		{
			String pathEnv = null;
			for(final String key : pb.environment().keySet())
			{
				if(key.equalsIgnoreCase("path"))
				{
					pathEnv = key;
				}
			}
			if(pathEnv == null)
			{
				throw new IllegalStateException("Could not find path variable!");
			}
			if(msysDir != null)
			{
				final String path = msysDir.getAbsolutePath() + ";" + new File(msysDir, "bin").getAbsolutePath() + ";" + pb.environment().get(pathEnv);
				pb.environment().put(pathEnv, path);
			}
			String path = pb.environment().get(pathEnv);
			if(!path.contains("C:\\WINDOWS\\system32;"))
			{
				path = System.getenv("SystemRoot") + "\\system32;" + path;
				pb.environment().put(pathEnv, path);
			}
		}
		final Process ps = pb.start();
		new Thread(new StreamRedirector(ps.getInputStream(), System.out), "System.out redirector").start();
		new Thread(new StreamRedirector(ps.getErrorStream(), System.err), "System.err redirector").start();
		final int status = ps.waitFor();
		if(status != 0)
		{
			throw new RuntimeException("Error running command, return status !=0: " + Arrays.toString(command));
		}
		return status;
	}

	public static void unzip(final File zipFile, final File targetFolder) throws IOException
	{
		unzip(zipFile, targetFolder, null);
	}

	public static void unzip(final File zipFile, final File targetFolder, final Predicate<String> filter) throws IOException
	{
		targetFolder.mkdir();
		final ZipFile zip = new ZipFile(zipFile);
		try
		{
			final Enumeration<? extends ZipEntry> entries = zip.entries();
			while(entries.hasMoreElements())
			{
				final ZipEntry entry = entries.nextElement();

				if(filter != null && !filter.test(entry.getName()))
				{
					continue;
				}
				final File outFile = new File(targetFolder, entry.getName());
				if(entry.isDirectory())
				{
					outFile.mkdirs();
				}
				else
				{
					if(outFile.getParentFile() != null)
					{
						outFile.getParentFile().mkdirs();
					}

					try(InputStream is = zip.getInputStream(entry))
					{
						Files.copy(is, outFile.toPath());
					}

					System.out.println("Extracted: " + outFile);
				}
			}
		}
		finally
		{
			zip.close();
		}
	}

	public static void download(final String url, final File target)
	{
		try
		{
			final ReadableByteChannel channel;

			HttpURLConnection connection = (HttpURLConnection) new URL(url).openConnection();
			connection.setRequestProperty("User-Agent", "TvheeAPIRepositoryDownloader");
			channel = Channels.newChannel(connection.getInputStream());
			final FileOutputStream output = new FileOutputStream(target);

			output.getChannel().transferFrom(channel, 0, Long.MAX_VALUE);
			output.flush();
			output.close();
		}
		catch(final Exception ex)
		{
			System.out.println("Could not download file " + target.getName() + ": " + ex.getMessage());
		}
	}
}