Inceptum/src/main/java/io/gitlab/jfronny/inceptum/windows/control/InstanceView.java

package io.gitlab.jfronny.inceptum.windows.control;

import imgui.ImGui;
import imgui.flag.ImGuiTableFlags;
import io.gitlab.jfronny.inceptum.Inceptum;
import io.gitlab.jfronny.inceptum.install.steps.DownloadLibrariesStep;
import io.gitlab.jfronny.inceptum.model.inceptum.ArtifactInfo;
import io.gitlab.jfronny.inceptum.model.inceptum.InstanceMeta;
import io.gitlab.jfronny.inceptum.model.mojang.MinecraftArgument;
import io.gitlab.jfronny.inceptum.model.mojang.VersionInfo;
import io.gitlab.jfronny.inceptum.model.mojang.VersionsListInfo;
import io.gitlab.jfronny.inceptum.util.ProcessUtils;
import io.gitlab.jfronny.inceptum.util.Utils;
import io.gitlab.jfronny.inceptum.util.VersionInfoLibraryResolver;
import io.gitlab.jfronny.inceptum.util.api.FabricMetaApi;
import io.gitlab.jfronny.inceptum.util.api.McApi;
import io.gitlab.jfronny.inceptum.util.api.account.AccountManager;
import io.gitlab.jfronny.inceptum.util.api.account.AuthInfo;
import io.gitlab.jfronny.inceptum.windows.InstanceEditWindow;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicReference;

public class InstanceView {
    public static void draw(List<Path> paths) {
        if (ImGui.beginTable("Instances", 2, ImGuiTableFlags.SizingFixedFit | ImGuiTableFlags.Borders)) {
            for (Path path : paths) {
                if (Files.exists(path.resolve("inceptum.setup.lock"))) {
                    ImGui.tableNextColumn();
                    ImGui.text("Setting up");
                    ImGui.tableNextColumn();
                    ImGui.text("This instance is currently being set up");
                    continue;
                }
                if (!Files.exists(path.resolve("instance.json"))) {
                    Inceptum.LOGGER.error("Invalid instance (doesn't contain instance.json): " + path);
                    continue;
                }
                InstanceMeta instance;
                try {
                    instance = Utils.loadObject(path.resolve("instance.json"), InstanceMeta.class);
                } catch (IOException e) {
                    Inceptum.LOGGER.error("Could not load instance.json", e);
                    continue;
                }
                ImGui.tableNextColumn();
                boolean disabled = false;
                if (Files.exists(path.resolve("inceptum.lock"))) {
                    try {
                        if (ProcessUtils.isProcessAlive(Files.readString(path.resolve("inceptum.lock"))))
                            disabled = true;
                        else Files.delete(path.resolve("inceptum.lock"));
                    } catch (IOException e) {
                        continue;
                    }
                }
                if (disabled) ImGui.beginDisabled();
                if (ImGui.button(path.getFileName().toString())) launch(path, instance);
                ImGui.tableNextColumn();
                if (ImGui.button("Edit##" + path)) Inceptum.open(new InstanceEditWindow(path, instance));
                if (disabled) ImGui.endDisabled();
            }
            ImGui.endTable();
        }
    }

    private static void launch(Path path, InstanceMeta instance) {
        for (VersionsListInfo version : McApi.getVersions().versions) {
            if (version.id.equals(instance.getMinecraftVersion())) {
                try {
                    List<String> args = new ArrayList<>();
                    VersionInfo info = McApi.getVersionInfo(version);
                    if (instance.isFabric()) {
                        FabricMetaApi.addFabric(info, instance.getLoaderVersion());
                    }
                    args.add(Objects.requireNonNullElseGet(instance.java, () ->
                            Utils.getJvmMain(Inceptum.NATIVES_DIR
                                    .resolve(info.javaVersion.component)
                                    .resolve(Integer.toString(info.javaVersion.majorVersion)))
                            .toAbsolutePath().toString()));
                    DownloadLibrariesStep.execute(info, new AtomicBoolean(false), new AtomicReference<>());
                    StringBuilder classPath = new StringBuilder();
                    for (ArtifactInfo artifact : VersionInfoLibraryResolver.getRelevant(info)) {
                        classPath.append(Inceptum.LIBRARIES_DIR.resolve(artifact.path).toAbsolutePath());
                        classPath.append(':');
                    }
                    classPath.append(Inceptum.LIBRARIES_DIR.resolve("net/minecraft/minecraft").resolve(version.id + ".jar").toAbsolutePath());
                    //TODO custom JVM args
                    if (info.arguments != null) args.addAll(parse(info.arguments.jvm, info, instance, classPath.toString(), path.toAbsolutePath().toString()));
                    if (instance.minMem != null) args.add("-Xms" + instance.minMem);
                    if (instance.maxMem != null) args.add("-Xmx" + instance.maxMem);
                    if (info.minecraftArguments != null) {
                        args.add("-cp");
                        args.add(classPath.toString());
                        args.add("-Djava.library.path=" + Inceptum.NATIVES_DIR.resolve(instance.getMinecraftVersion()).toAbsolutePath());
                    }
                    args.add(info.mainClass);
                    if (info.arguments != null) args.addAll(parse(info.arguments.game, info, instance, classPath.toString(), path.toAbsolutePath().toString()));
                    else if (info.minecraftArguments != null) {
                        for (String s : info.minecraftArguments.split(" ")) {
                            args.add(expandArg(s, info, instance, classPath.toString(), path.toAbsolutePath().toString()));
                        }
                    }
                    else {
                        Inceptum.LOGGER.error("Could not launch: No valid argument source found");
                        return;
                    }
                    Inceptum.LOGGER.info(String.join(" ", args));
                    ProcessBuilder pb = new ProcessBuilder(args.toArray(new String[0]));
                    pb.directory(path.toFile());
                    pb.redirectOutput(ProcessBuilder.Redirect.INHERIT);
                    pb.redirectError(ProcessBuilder.Redirect.INHERIT);
                    Files.writeString(path.resolve("inceptum.lock"), Long.toString(pb.start().pid()));
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    private static List<String> parse(List<MinecraftArgument> arguments, VersionInfo info, InstanceMeta instance, String classPath, String gameDirectory) {
        List<String> res = new ArrayList<>();
        for (MinecraftArgument argument : arguments) {
            for (String s : argument.arg()) {
                res.add(expandArg(s, info, instance, classPath, gameDirectory));
            }
        }
        return res;
    }

    private static String expandArg(String arg, VersionInfo info, InstanceMeta instance, String classPath, String gameDirectory) {
        AuthInfo authInfo = AccountManager.getSelectedAccount();
        return arg
                // game args
                .replace("${auth_player_name}", authInfo.name())
                .replace("${version_name}", instance.getMinecraftVersion())
                .replace("${game_directory}", gameDirectory)
                .replace("${assets_root}", Inceptum.ASSETS_DIR.toAbsolutePath().toString())
                .replace("${assets_index_name}", info.assets)
                .replace("${auth_uuid}", authInfo.uuid())
                .replace("${auth_access_token}", authInfo.accessToken())
                .replace("${user_type}", authInfo.userType())
                .replace("${version_type}", info.type)
                .replace("${resolution_width}", "1920") //TODO has_custom_resolution
                .replace("${resolution_height}", "1080") //TODO has_custom_resolution
                // jvm args
                .replace("${natives_directory}", Inceptum.NATIVES_DIR.resolve(instance.getMinecraftVersion()).toAbsolutePath().toString())
                .replace("${launcher_name}", "Inceptum")
                .replace("${launcher_version}", Inceptum.VERSION.version)
                .replace("${classpath}", classPath)
                .replace("${user_properties}", "{}");
    }
}