/*
 * Copyright (C) 2011-2021 lishid. All rights reserved.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, version 3.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

package com.lishid.openinv.commands;

import com.lishid.openinv.OpenInv;
import com.lishid.openinv.util.TabCompleter;
import java.util.Collections;
import java.util.List;
import org.bukkit.Material;
import org.bukkit.NamespacedKey;
import org.bukkit.command.Command;
import org.bukkit.command.CommandSender;
import org.bukkit.command.TabExecutor;
import org.bukkit.enchantments.Enchantment;
import org.bukkit.entity.Player;
import org.bukkit.inventory.Inventory;
import org.bukkit.inventory.ItemStack;
import org.bukkit.inventory.meta.ItemMeta;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

/**
 * Command adding the ability to search online players' inventories for enchantments of a specific
 * type at or above the level specified.
 *
 * @author Jikoo
 */
public class SearchEnchantCommand implements TabExecutor {

    private final OpenInv plugin;

    public SearchEnchantCommand(OpenInv plugin) {
        this.plugin = plugin;
    }

    @Override
    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
        if (args.length == 0) {
            return false;
        }

        Enchantment enchant = null;
        int level = 0;

        for (String argument : args) {
            try {
                level = Integer.parseInt(argument);
                continue;
            } catch (NumberFormatException ignored) {}

            argument = argument.toLowerCase();
            int colon = argument.indexOf(':');
            NamespacedKey key;
            try {
                if (colon > -1 && colon < argument.length() - 1) {
                    key = new NamespacedKey(argument.substring(0, colon), argument.substring(colon + 1));
                } else {
                    key = NamespacedKey.minecraft(argument);
                }
            } catch (IllegalArgumentException ignored) {
                continue;
            }

            Enchantment localEnchant = Enchantment.getByKey(key);
            if (localEnchant != null) {
                enchant = localEnchant;
            }
        }

        // Arguments not set correctly
        if (level == 0 && enchant == null) {
            return false;
        }

        StringBuilder players = new StringBuilder();
        for (Player player : plugin.getServer().getOnlinePlayers()) {
            boolean flagInventory = containsEnchantment(player.getInventory(), enchant, level);
            boolean flagEnder = containsEnchantment(player.getEnderChest(), enchant, level);

            // No matches, continue
            if (!flagInventory && !flagEnder) {
                continue;
            }

            // Matches, append details
            players.append(player.getName()).append(" (");
            if (flagInventory) {
                players.append("inv");
            }
            if (flagEnder) {
                if (flagInventory) {
                    players.append(',');
                }
                players.append("ender");
            }
            players.append("), ");
        }

        if (players.length() > 0) {
            // Matches found, delete trailing comma and space
            players.delete(players.length() - 2, players.length());
        } else {
            plugin.sendMessage(sender, "messages.info.player.noMatches",
                    "%target%", (enchant != null ? enchant.getKey().toString() : "") + " >= " + level);
            return true;
        }

        plugin.sendMessage(sender, "messages.info.player.matches",
                "%target%", (enchant != null ? enchant.getKey().toString() : "") + " >= " + level,
                "%detail%", players.toString());
        return true;
    }

    private boolean containsEnchantment(Inventory inventory, @Nullable Enchantment enchant, int minLevel) {
        for (ItemStack item : inventory.getContents()) {
            //noinspection ConstantConditions // Spigot improperly annotated, should be ItemStack @NotNull []
            if (item == null || item.getType() == Material.AIR) {
                continue;
            }
            if (enchant != null) {
                if (item.containsEnchantment(enchant) && item.getEnchantmentLevel(enchant) >= minLevel) {
                    return true;
                }
            } else {
                if (!item.hasItemMeta()) {
                    continue;
                }
                ItemMeta meta = item.getItemMeta();
                if (meta == null || !meta.hasEnchants()) {
                    continue;
                }
                for (int enchLevel : meta.getEnchants().values()) {
                    if (enchLevel >= minLevel) {
                        return true;
                    }
                }
            }
        }
        return false;
    }

    @Override
    public List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
        if (!command.testPermissionSilent(sender) || args.length < 1 || args.length > 2) {
            return Collections.emptyList();
        }

        if (args.length == 1) {
            return TabCompleter.completeObject(args[0], enchantment -> enchantment.getKey().toString(), Enchantment.values());
        } else {
            return TabCompleter.completeInteger(args[1]);
        }
    }

}