fix: cooldown serveur 2s/8s + loot dans transaction (élimine deadlock)

src/combat/combat.service.ts

@@ -1,6 +1,7 @@
 import { Injectable, BadRequestException, ConflictException } from '@nestjs/common';
 import { InjectRepository } from '@nestjs/typeorm';
-import { DataSource, Repository } from 'typeorm';
+import { DataSource, EntityManager, Repository } from 'typeorm';
+import { CharacterMaterial } from '../material/character-material.entity';
 import { EventEmitter2 } from '@nestjs/event-emitter';
 import { Character } from '../character/entities/character.entity';
 import { Monster } from '../monster/monster.entity';
@@ -54,8 +55,25 @@ const DEFEAT_HP_RATIO = 0.2;    // 20% hpMax à la défaite
 const VICTORY_HP_REGEN_RATIO = 0.1; // +10% hpMax à la victoire
 const DEFEAT_GOLD_LOSS_RATIO = 0.05; // perte 5% or à la défaite
 
+/** Ajouter un matériau dans la transaction courante (pas de connexion séparée). */
+async function addMaterialInTx(manager: EntityManager, characterId: string, materialId: string, quantity: number) {
+  const repo = manager.getRepository(CharacterMaterial);
+  let entry = await repo.findOne({ where: { characterId, materialId } });
+  if (entry) {
+    entry.quantity += quantity;
+  } else {
+    entry = repo.create({ characterId, materialId, quantity });
+  }
+  await repo.save(entry);
+}
+
+const COOLDOWN_SINGLE_MS = 2_000;
+const COOLDOWN_MULTI_MS = 8_000;
+
 @Injectable()
 export class CombatService {
+  private readonly cooldowns = new Map<string, number>(); // userId → timestamp
+
   constructor(
     @InjectRepository(Character)
     private readonly characterRepository: Repository<Character>,
@@ -69,7 +87,23 @@ export class CombatService {
     private readonly dataSource: DataSource,
   ) {}
 
+  private checkCooldown(userId: string): void {
+    const lastCombat = this.cooldowns.get(userId) ?? 0;
+    const remaining = lastCombat - Date.now();
+    if (remaining > 0) {
+      throw new BadRequestException(
+        `Cooldown actif — attendez ${Math.ceil(remaining / 1000)}s`,
+      );
+    }
+  }
+
+  private setCooldown(userId: string, durationMs: number): void {
+    this.cooldowns.set(userId, Date.now() + durationMs);
+  }
+
   async startCombat(dto: StartCombatDto, user: User) {
+    this.checkCooldown(user.id);
+
     // Charger le monstre (hors transaction — lecture seule)
     const monster = await this.monsterService.findOne(dto.monsterId);
 
@@ -202,7 +236,7 @@ export class CombatService {
       if (result.winner === 'player' && monster.dropMaterialId) {
         const { dropRate, dropQty } = computeDropRate(character.level, monster.minLevel, monster.maxLevel);
         if (Math.random() < dropRate) {
-          await this.materialService.addMaterial(character.id, monster.dropMaterialId, dropQty);
+          await addMaterialInTx(manager, character.id, monster.dropMaterialId, dropQty);
           lootMaterial = { name: 'matériau', quantity: dropQty };
           lootedMaterialId = monster.dropMaterialId;
         }
@@ -284,10 +318,12 @@ export class CombatService {
       }
     }
 
+    this.setCooldown(user.id, COOLDOWN_SINGLE_MS);
     return txResult.response;
   }
 
   async startMultiCombat(dto: StartCombatDto, user: User, count: number) {
+    this.checkCooldown(user.id);
     const monster = await this.monsterService.findOne(dto.monsterId);
 
     const txResult = await this.dataSource.transaction(async (manager) => {
@@ -368,7 +404,7 @@ export class CombatService {
           if (monster.dropMaterialId) {
             const { dropRate, dropQty } = computeDropRate(character.level, monster.minLevel, monster.maxLevel);
             if (Math.random() < dropRate) {
-              await this.materialService.addMaterial(character.id, monster.dropMaterialId, dropQty);
+              await addMaterialInTx(manager, character.id, monster.dropMaterialId, dropQty);
               totals.loot.push({ name: 'matériau', quantity: dropQty });
               lootedMaterialIds.push(monster.dropMaterialId);
             }
@@ -428,6 +464,7 @@ export class CombatService {
       }
     }
 
+    this.setCooldown(user.id, COOLDOWN_MULTI_MS);
     return {
       mode: 'multi',
       count: txResult.combatsDone,