package com.zombie.game.template;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.InputStream;
import java.util.*;

/**
 * 模板管理器
 *
 * 负责从 JSON 配置文件加载和管理所有游戏模板（僵尸、武器、玩家）。
 * 单例模式，在服务器启动时加载一次。
 */
public class TemplateManager {
    private static final Logger logger = LoggerFactory.getLogger(TemplateManager.class);
    private static TemplateManager instance;

    private final Map<String, ZombieTemplate> zombieTemplates = new LinkedHashMap<>();
    private final Map<String, WeaponTemplate> weaponTemplates = new LinkedHashMap<>();
    private PlayerTemplate playerTemplate;

    private TemplateManager() {
        loadAll();
    }

    public static synchronized TemplateManager getInstance() {
        if (instance == null) {
            instance = new TemplateManager();
        }
        return instance;
    }

    private void loadAll() {
        loadZombies();
        loadWeapons();
        loadPlayer();
        logger.info("Templates loaded: {} zombies, {} weapons, 1 player base",
            zombieTemplates.size(), weaponTemplates.size());
    }

    private void loadZombies() {
        try (InputStream is = getClass().getResourceAsStream("/data/zombies.json")) {
            ObjectMapper mapper = new ObjectMapper();
            JsonNode root = mapper.readTree(is);
            JsonNode types = root.get("types");
            for (JsonNode node : types) {
                ZombieTemplate t = new ZombieTemplate(
                    node.get("id").asText(),
                    node.get("name").asText(),
                    (float) node.get("baseHealth").asDouble(),
                    (float) node.get("baseSpeed").asDouble(),
                    (float) node.get("damage").asDouble(),
                    (float) node.get("attackRate").asDouble(),
                    node.get("canRangedAttack").asBoolean(),
                    (float) node.get("rangedRange").asDouble(),
                    node.get("rangedDamage").asInt(),
                    (float) node.get("rangedBulletSpeed").asDouble(),
                    node.get("canSplit").asBoolean(),
                    node.get("minSplit").asInt(),
                    node.get("maxSplit").asInt(),
                    (float) node.get("spawnWeight").asDouble()
                );
                zombieTemplates.put(t.getId(), t);
            }
        } catch (Exception e) {
            throw new RuntimeException("Failed to load zombie templates", e);
        }
    }

    private void loadWeapons() {
        try (InputStream is = getClass().getResourceAsStream("/data/weapons.json")) {
            ObjectMapper mapper = new ObjectMapper();
            JsonNode root = mapper.readTree(is);
            JsonNode types = root.get("types");
            for (JsonNode node : types) {
                WeaponTemplate t = new WeaponTemplate(
                    node.get("id").asText(),
                    node.get("name").asText(),
                    node.has("category") ? node.get("category").asText() : "firearm",
                    node.get("damage").asInt(),
                    node.get("fireRate").asLong(),
                    node.get("pelletCount").asInt(),
                    (float) node.get("spread").asDouble(),
                    (float) node.get("bulletSpeed").asDouble(),
                    (float) node.get("range").asDouble(),
                    node.get("maxAmmo").asInt(),
                    node.get("chargeable").asBoolean(),
                    node.get("explosive").asBoolean(),
                    (float) node.get("explosionRadius").asDouble(),
                    node.has("fireZoneRadius") ? (float) node.get("fireZoneRadius").asDouble() : 0,
                    node.has("fireZoneDamage") ? (float) node.get("fireZoneDamage").asDouble() : 0,
                    node.has("fireZoneDuration") ? (float) node.get("fireZoneDuration").asDouble() : 0,
                    node.has("turretHealth") ? (float) node.get("turretHealth").asDouble() : 0,
                    node.has("turretRange") ? (float) node.get("turretRange").asDouble() : 0,
                    node.has("turretFireRate") ? node.get("turretFireRate").asLong() : 0,
                    node.has("turretDamage") ? node.get("turretDamage").asInt() : 0,
                    node.has("turretBulletSpeed") ? (float) node.get("turretBulletSpeed").asDouble() : 0
                );
                weaponTemplates.put(t.getId(), t);
            }
        } catch (Exception e) {
            throw new RuntimeException("Failed to load weapon templates", e);
        }
    }

    private void loadPlayer() {
        try (InputStream is = getClass().getResourceAsStream("/data/players.json")) {
            ObjectMapper mapper = new ObjectMapper();
            JsonNode root = mapper.readTree(is);
            JsonNode base = root.get("base");
            playerTemplate = new PlayerTemplate(
                (float) base.get("speed").asDouble(),
                (float) base.get("maxHealth").asDouble(),
                (float) base.get("invulnerableTime").asDouble(),
                (float) base.get("respawnTime").asDouble(),
                (float) base.get("size").asDouble()
            );
        } catch (Exception e) {
            throw new RuntimeException("Failed to load player template", e);
        }
    }

    public ZombieTemplate getZombieTemplate(String id) {
        return zombieTemplates.get(id);
    }

    public Collection<ZombieTemplate> getAllZombieTemplates() {
        return zombieTemplates.values();
    }

    public WeaponTemplate getWeaponTemplate(String id) {
        return weaponTemplates.get(id);
    }

    public Collection<WeaponTemplate> getAllWeaponTemplates() {
        return weaponTemplates.values();
    }

    public PlayerTemplate getPlayerTemplate() {
        return playerTemplate;
    }

    public int getWeaponIndex(String id) {
        int idx = 0;
        for (String key : weaponTemplates.keySet()) {
            if (key.equals(id)) return idx;
            idx++;
        }
        return 0;
    }

    public String getWeaponId(int index) {
        int idx = 0;
        for (String key : weaponTemplates.keySet()) {
            if (idx == index) return key;
            idx++;
        }
        return weaponTemplates.keySet().iterator().next();
    }
}