package io.gitlab.jfronny.inceptum.cli.commands;

import io.gitlab.jfronny.commons.io.JFiles;
import io.gitlab.jfronny.commons.throwable.ThrowingBiFunction;
import io.gitlab.jfronny.inceptum.cli.*;
import io.gitlab.jfronny.inceptum.common.Utils;
import io.gitlab.jfronny.inceptum.launcher.system.instance.Instance;
import io.gitlab.jfronny.inceptum.launcher.system.instance.ModManager;
import io.gitlab.jfronny.inceptum.launcher.system.instance.ModPath;
import io.gitlab.jfronny.inceptum.launcher.system.instance.Mod;
import io.gitlab.jfronny.inceptum.launcher.system.mds.ModsDirScanner;
import io.gitlab.jfronny.inceptum.launcher.system.source.ModSource;
import io.gitlab.jfronny.inceptum.launcher.util.Unchecked;

import java.io.*;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.*;

public class ModCommand extends Command {
    //TODO ModAddCommand (search and install)
    public ModCommand() {
        super("Allows managing mods in instances", "", List.of("mod"), List.of(
                new ModListCommand(),
                new ModUpdateCommand(),
                new ModRemoveCommand()
        ));
    }

    @Override
    protected void invoke(CommandArgs args) {
        Utils.LOGGER.error("No known mod command was specified");
    }

    public static class ModListCommand extends BaseInstanceCommand {
        private final boolean filterUpdatable;

        public ModListCommand() {
            this("Lists the mods in an instance", List.of("list", "ls"), List.of(
                    new ModListCommand("List only updatable mods", List.of("updatable"), List.of(), true)
            ), false);
        }

        private ModListCommand(String help, List<String> aliases, List<Command> subCommands, boolean filterUpdatable) {
            super(help, "", aliases, subCommands);
            this.filterUpdatable = filterUpdatable;
        }

        @Override
        protected void invoke(CommandArgs args, Instance instance) throws IOException {
            if (!instance.isFabric()) {
                System.err.println("This is not a fabric instance");
                return;
            }
            System.out.println("Scanning installed mods, this might take a while");
            instance.mds().runOnce((path, mod) -> {
                boolean hasSources = !mod.getMetadata().sources.isEmpty();
                boolean updatable = hasSources && mod.getMetadata().sources.values().stream().anyMatch(Optional::isPresent);
                if (filterUpdatable && !updatable) return;
                System.out.println("- " + path.getFileName().toString());
                System.out.println("  " + mod.getName());
                for (String s : mod.getDescription()) {
                    System.out.println("  " + s);
                }
                if (hasSources) {
                    System.out.println("  Sources:");
                    for (Map.Entry<ModSource, Optional<ModSource>> entry : mod.getMetadata().sources.entrySet()) {
                        System.out.println("  - " + entry.getKey().getName() + " (" + entry.getKey().getVersion() + ")");
                        System.out.println("    Local: " + entry.getKey().getJarPath().toString());
                        if (entry.getValue().isPresent())
                            System.out.println("    Updatable to: " + entry.getValue().get().getVersion());
                    }
                }
            });
        }
    }

    public static class ModRemoveCommand extends BaseInstanceCommand {
        private final boolean ignoreDependencies;

        public ModRemoveCommand() {
            this("Removes mods from an instance", List.of("remove", "delete", "rm", "del"), List.of(
                    new ModRemoveCommand("Skip dependency checks", List.of("ignore-dependencies"), List.of(), true)
            ), false);
        }

        private ModRemoveCommand(String help, List<String> aliases, List<Command> subCommands, boolean ignoreDependencies) {
            super(help, "<mod file>...", aliases, subCommands);
            this.ignoreDependencies = ignoreDependencies;
        }

        @Override
        protected void invoke(CommandArgs args, Instance instance) throws IOException {
            if (!instance.isFabric()) {
                Utils.LOGGER.error("This is not a fabric instance");
                return;
            }
            if (args.length == 0) {
                Utils.LOGGER.error("You must specify mods to remove");
                return;
            }
            Set<Path> mods = new HashSet<>();
            for (String arg : args) {
                Path p = instance.modsDir().resolve(arg);
                if (!Files.exists(p)) p = instance.modsDir().resolve(arg + ".imod");
                if (!Files.exists(p)) {
                    Utils.LOGGER.error("Nonexistant mod file: " + instance.modsDir().resolve(arg));
                    return;
                }
                mods.add(p);
            }
            ModsDirScanner mds = instance.mds();
            if (!ignoreDependencies && !mds.isComplete()) {
                Utils.LOGGER.error("Scanning mods dir to search for dependencies. This might take a while");
                mds.runOnce((path, mod) -> System.out.println("Scanned " + path));
            }
            for (Path mod : mods) {
                try {
                    mds.get(mod).delete();
                } catch (IOException e) {
                    Utils.LOGGER.error("Could not delete " + mod, e);
                    return;
                }
            }
        }
    }

    public static class ModUpdateCommand extends BaseInstanceCommand {
        private final ThrowingBiFunction<CommandArgs, Path, Set<Path>, IOException> pathSupplier;

        public ModUpdateCommand() {
            this("Update mods in an instance", "<mod file>...", List.of("update", "upgrade", "up"), List.of(
                    new ModUpdateCommand("Update all mods in an instance", "", List.of("all"), List.of(), (args, instancePath) -> Set.copyOf(JFiles.list(instancePath)))
            ), (args, instancePath) -> {
                Set<Path> mods = new HashSet<>();
                for (String arg : args) {
                    Path p = instancePath.resolve("mods").resolve(arg);
                    if (!Files.exists(p)) p = instancePath.resolve("mods").resolve(arg + ".imod");
                    if (!Files.exists(p)) {
                        throw new FileNotFoundException("Nonexistant mod file: " + instancePath.resolve("mods").resolve(arg));
                    }
                    mods.add(p);
                }
                return mods;
            });
        }

        private ModUpdateCommand(String help, String usage, List<String> aliases, List<Command> subCommands, ThrowingBiFunction<CommandArgs, Path, Set<Path>, IOException> pathSupplier) {
            super(help, usage, aliases, subCommands);
            this.pathSupplier = pathSupplier;
        }

        @Override
        protected void invoke(CommandArgs args, Instance instance) throws IOException {
            if (!instance.isFabric()) {
                throw new IOException("This is not a fabric instance");
            }
            if (args.length == 0) {
                throw new IllegalArgumentException("You must specify mods to remove");
            }
            Set<Path> mods = pathSupplier.apply(args, instance.path());
            ModsDirScanner mds = instance.mds();
            if (!mds.isComplete()) {
                Utils.LOGGER.error("Scanning mods dir to search for dependencies. This might take a while");
                mds.runOnce((path, mod) -> System.out.println("Scanned " + path));
            }
            for (Path mod : mods) {
                try {
                    mds.get(mod).delete();
                    Mod md = mds.get(mod);
                    md.getMetadata().sources.values().stream()
                            .filter(Optional::isPresent)
                            .map(Optional::get)
                            .findFirst()
                            .ifPresentOrElse(update -> {
                                try {
                                    Utils.LOGGER.info("Updating " + mod + " to " + update.getVersion());
                                    md.update(update);
                                    Utils.LOGGER.info("Update completed");
                                } catch (IOException e) {
                                    throw new Unchecked(e);
                                }
                                }, () -> Utils.LOGGER.error("Could not find any update for " + mod));
                } catch (IOException e) {
                    throw new IOException("Could not delete " + mod, e);
                } catch (Unchecked e) {
                    throw new IOException("Could not delete " + mod, e.exception);
                }
            }
        }
    }
}