import { prisma } from '../../core/database/prisma'
import { addItemByKey, adjustCoins, findItemByKey, getInventoryEntry } from '../economy/service';
import type { ItemProps, InventoryState } from '../economy/types';
import type { LevelRequirements, RunMinigameOptions, RunResult, RewardsTable, MobsTable } from './types';
import type { Prisma } from '@prisma/client';

function parseJSON<T>(v: unknown): T | null {
  if (!v || (typeof v !== 'object' && typeof v !== 'string')) return null;
  return v as T;
}

function pickWeighted<T extends { weight: number }>(arr: T[]): T | null {
  const total = arr.reduce((s, a) => s + Math.max(0, a.weight || 0), 0);
  if (total <= 0) return null;
  const r = Math.random() * total;
  let acc = 0;
  for (const a of arr) {
    acc += Math.max(0, a.weight || 0);
    if (r <= acc) return a;
  }
  return arr[arr.length - 1] ?? null;
}

async function ensureAreaAndLevel(guildId: string, areaKey: string, level: number) {
  const area = await prisma.gameArea.findFirst({ where: { key: areaKey, OR: [{ guildId }, { guildId: null }] }, orderBy: [{ guildId: 'desc' }] });
  if (!area) throw new Error('Área no encontrada');
  const lvl = await prisma.gameAreaLevel.findFirst({ where: { areaId: area.id, level } });
  if (!lvl) throw new Error('Nivel no encontrado');
  return { area, lvl } as const;
}

function parseItemProps(json: unknown): ItemProps {
  if (!json || typeof json !== 'object') return {};
  return json as ItemProps;
}

function parseInvState(json: unknown): InventoryState {
  if (!json || typeof json !== 'object') return {};
  return json as InventoryState;
}

async function validateRequirements(userId: string, guildId: string, req?: LevelRequirements, toolKey?: string) {
  if (!req) return { toolKeyUsed: undefined as string | undefined };
  const toolReq = req.tool;
  if (!toolReq) return { toolKeyUsed: undefined as string | undefined };

  // herramienta requerida
  if (toolReq.required && !toolKey) throw new Error('Se requiere una herramienta');
  if (!toolKey) return { toolKeyUsed: undefined };

  // verificar herramienta
  const toolItem = await findItemByKey(guildId, toolKey);
  if (!toolItem) throw new Error('Herramienta no encontrada');
  const { entry } = await getInventoryEntry(userId, guildId, toolKey);
  if (!entry || (entry.quantity ?? 0) <= 0) throw new Error('No tienes la herramienta');

  const props = parseItemProps(toolItem.props);
  const tool = props.tool;
  if (toolReq.toolType && tool?.type !== toolReq.toolType) throw new Error('Tipo de herramienta incorrecto');
  if (toolReq.minTier != null && (tool?.tier ?? 0) < toolReq.minTier) throw new Error('Tier de herramienta insuficiente');
  if (toolReq.allowedKeys && !toolReq.allowedKeys.includes(toolKey)) throw new Error('Esta herramienta no es válida para esta área');

  return { toolKeyUsed: toolKey };
}

async function applyRewards(userId: string, guildId: string, rewards?: RewardsTable): Promise<RunResult['rewards']> {
  const results: RunResult['rewards'] = [];
  if (!rewards || !Array.isArray(rewards.table) || rewards.table.length === 0) return results;
  const draws = Math.max(1, rewards.draws ?? 1);
  for (let i = 0; i < draws; i++) {
    const pick = pickWeighted(rewards.table);
    if (!pick) continue;
    if (pick.type === 'coins') {
      const amt = Math.max(0, pick.amount);
      if (amt > 0) {
        await adjustCoins(userId, guildId, amt);
        results.push({ type: 'coins', amount: amt });
      }
    } else if (pick.type === 'item') {
      const qty = Math.max(1, pick.qty);
      await addItemByKey(userId, guildId, pick.itemKey, qty);
      results.push({ type: 'item', itemKey: pick.itemKey, qty });
    }
  }
  return results;
}

async function sampleMobs(mobs?: MobsTable): Promise<string[]> {
  const out: string[] = [];
  if (!mobs || !Array.isArray(mobs.table) || mobs.table.length === 0) return out;
  const draws = Math.max(0, mobs.draws ?? 0);
  for (let i = 0; i < draws; i++) {
    const pick = pickWeighted(mobs.table);
    if (pick) out.push(pick.mobKey);
  }
  return out;
}

async function reduceToolDurability(userId: string, guildId: string, toolKey: string) {
  const { item, entry } = await getInventoryEntry(userId, guildId, toolKey);
  if (!entry) return { broken: false, delta: 0 } as const;
  const props = parseItemProps(item.props);
  const breakable = props.breakable;
  const delta = Math.max(1, breakable?.durabilityPerUse ?? 1);
  if (item.stackable) {
    // Herramientas deberían ser no apilables; si lo son, solo decrementamos cantidad como fallback
    const consumed = Math.min(1, entry.quantity);
    if (consumed > 0) {
      await prisma.inventoryEntry.update({ where: { userId_guildId_itemId: { userId, guildId, itemId: item.id } }, data: { quantity: { decrement: consumed } } });
    }
    return { broken: consumed > 0, delta } as const;
  }
  const state = parseInvState(entry.state);
  state.instances ??= [{}];
  if (state.instances.length === 0) state.instances.push({});
  const inst = state.instances[0];
  const max = Math.max(1, breakable?.maxDurability ?? 1);
  const current = Math.min(Math.max(0, inst.durability ?? max), max);
  const next = current - delta;
  let broken = false;
  if (next <= 0) {
    // romper: eliminar instancia
    state.instances.shift();
    broken = true;
  } else {
    (inst as any).durability = next;
    state.instances[0] = inst;
  }
  await prisma.inventoryEntry.update({
    where: { userId_guildId_itemId: { userId, guildId, itemId: item.id } },
    data: { state: state as unknown as Prisma.InputJsonValue, quantity: state.instances.length },
  });
  return { broken, delta } as const;
}

export { reduceToolDurability };

export async function runMinigame(userId: string, guildId: string, areaKey: string, level: number, opts?: RunMinigameOptions): Promise<RunResult> {
  const { area, lvl } = await ensureAreaAndLevel(guildId, areaKey, level);

  // Cooldown por área
  const areaConf = (area.config as any) ?? {};
  const cdSeconds = Math.max(0, Number(areaConf.cooldownSeconds ?? 0));
  const cdKey = `minigame:${area.key}`;
  if (cdSeconds > 0) {
    const existing = await prisma.actionCooldown.findUnique({ where: { userId_guildId_key: { userId, guildId, key: cdKey } } });
    if (existing && existing.until > new Date()) {
      throw new Error('Cooldown activo para esta actividad');
    }
  }

  // Leer configuración de nivel (requirements, rewards, mobs)
  const requirements = parseJSON<LevelRequirements>(lvl.requirements) ?? {};
  const rewards = parseJSON<RewardsTable>(lvl.rewards) ?? { table: [] };
  const mobs = parseJSON<MobsTable>(lvl.mobs) ?? { table: [] };

  // Validar herramienta si aplica
  const reqRes = await validateRequirements(userId, guildId, requirements, opts?.toolKey);

  // Aplicar recompensas y samplear mobs
  const delivered = await applyRewards(userId, guildId, rewards);
  const mobsSpawned = await sampleMobs(mobs);

  // Reducir durabilidad de herramienta si se usó
  let toolInfo: RunResult['tool'] | undefined;
  if (reqRes.toolKeyUsed) {
    const t = await reduceToolDurability(userId, guildId, reqRes.toolKeyUsed);
    toolInfo = { key: reqRes.toolKeyUsed, durabilityDelta: t.delta, broken: t.broken };
  }

  // Registrar la ejecución
  const resultJson: Prisma.InputJsonValue = {
    rewards: delivered,
    mobs: mobsSpawned,
    tool: toolInfo,
    notes: 'auto',
  } as unknown as Prisma.InputJsonValue;

  await prisma.minigameRun.create({
    data: {
      userId,
      guildId,
      areaId: area.id,
      level,
      toolItemId: null, // opcional si decides guardar id del item herramienta
      success: true,
      result: resultJson,
    },
  });

  // Progreso del jugador
  await prisma.playerProgress.upsert({
    where: { userId_guildId_areaId: { userId, guildId, areaId: area.id } },
    create: { userId, guildId, areaId: area.id, highestLevel: Math.max(1, level) },
    update: { highestLevel: { set: level } },
  });

  // Setear cooldown
  if (cdSeconds > 0) {
    await prisma.actionCooldown.upsert({
      where: { userId_guildId_key: { userId, guildId, key: cdKey } },
      update: { until: new Date(Date.now() + cdSeconds * 1000) },
      create: { userId, guildId, key: cdKey, until: new Date(Date.now() + cdSeconds * 1000) },
    });
  }

  return { success: true, rewards: delivered, mobs: mobsSpawned, tool: toolInfo };
}