fix(streaks): use user timezone for date strings (#241)

backend/src/database/migrations/20250601204322-AddDifficultyAndCategoryToIQQuestions.ts

@@ -1,8 +1,6 @@
 import { MigrationInterface, QueryRunner } from 'typeorm';
 
-export class AddDifficultyAndCategoryToIQQuestions20250601204322
-  implements MigrationInterface
-{
+export class AddDifficultyAndCategoryToIQQuestions20250601204322 implements MigrationInterface {
   name = 'AddDifficultyAndCategoryToIQQuestions20250601204322';
 
   public async up(queryRunner: QueryRunner): Promise<void> {

backend/src/database/migrations/20250601204323-CreateDailyStreaksTable.ts

@@ -1,8 +1,6 @@
 import { MigrationInterface, QueryRunner } from 'typeorm';
 
-export class CreateDailyStreaksTable20250601204323
-  implements MigrationInterface
-{
+export class CreateDailyStreaksTable20250601204323 implements MigrationInterface {
   name = 'CreateDailyStreaksTable20250601204323';
 
   public async up(queryRunner: QueryRunner): Promise<void> {

backend/src/progress/providers/get-category-stats.provider.ts

@@ -3,16 +3,6 @@ import { InjectRepository } from '@nestjs/typeorm';
 import { FindOptionsWhere, Repository } from 'typeorm';
 import { UserProgress } from '../entities/progress.entity';
 
-interface CategoryStatsRaw {
-  categoryId: string;
-  totalAttempts: string;
-  correctAnswers: string;
-}
-
-interface CategoryNameRaw {
-  category_name: string;
-}
-
 @Injectable()
 export class GetCategoryStatsProvider {
   constructor(

backend/src/progress/providers/get-overall-stats.provider.ts

@@ -4,13 +4,6 @@ import { FindOptionsWhere, Repository } from 'typeorm';
 import { UserProgress } from '../entities/progress.entity';
 import { OverallStatsDto } from '../dtos/overall-stats.dto';
 
-interface OverallStatsRaw {
-  totalAttempts: string;
-  totalCorrect: string;
-  totalPointsEarned: string;
-  totalTimeSpent: string;
-}
-
 @Injectable()
 export class GetOverallStatsProvider {
   constructor(

backend/src/progress/providers/progress-calculation.provider.ts

@@ -6,7 +6,6 @@ import { UserProgress } from '../entities/progress.entity';
 import { SubmitAnswerDto } from '../dtos/submit-answer.dto';
 import { XpLevelService } from '../../users/providers/xp-level.service';
 import { User } from '../../users/user.entity';
-import { Streak } from '../../streak/entities/streak.entity';
 import { DailyQuest } from '../../quests/entities/daily-quest.entity';
 import { getPointsByDifficulty } from '../../puzzles/enums/puzzle-difficulty.enum';
 
@@ -21,13 +20,6 @@ export interface ProgressCalculationResult {
   validation: AnswerValidationResult;
 }
 
-interface ProgressStatsRaw {
-  totalAttempts: string;
-  correctAttempts: string;
-  totalPoints: string;
-  averageTimeSpent: string;
-}
-
 @Injectable()
 export class ProgressCalculationProvider {
   constructor(
@@ -38,8 +30,6 @@ export class ProgressCalculationProvider {
     private readonly xpLevelService: XpLevelService,
     @InjectRepository(User)
     private readonly userRepository: Repository<User>,
-    @InjectRepository(Streak)
-    private readonly streakRepository: Repository<Streak>,
     @InjectRepository(DailyQuest)
     private readonly dailyQuestRepository: Repository<DailyQuest>,
   ) {}

backend/src/puzzles/dtos/create-puzzle.dto.ts

@@ -20,9 +20,7 @@ import {
 } from '../enums/puzzle-difficulty.enum';
 
 @ValidatorConstraint({ name: 'correctAnswerInOptions', async: false })
-export class CorrectAnswerInOptionsConstraint
-  implements ValidatorConstraintInterface
-{
+export class CorrectAnswerInOptionsConstraint implements ValidatorConstraintInterface {
   validate(correctAnswer: string, args: ValidationArguments) {
     const object = args.object as CreatePuzzleDto;
     return object.options?.includes(correctAnswer) || false;
@@ -34,9 +32,7 @@ export class CorrectAnswerInOptionsConstraint
 }
 
 @ValidatorConstraint({ name: 'optionsMinimumLength', async: false })
-export class OptionsMinimumLengthConstraint
-  implements ValidatorConstraintInterface
-{
+export class OptionsMinimumLengthConstraint implements ValidatorConstraintInterface {
   validate(options: string[]) {
     return options?.length >= 2;
   }

backend/src/quests/controllers/daily-quest.controller.ts

@@ -41,6 +41,7 @@ export class DailyQuestController {
   })
   async getTodaysDailyQuest(
     @ActiveUser('sub') userId: string,
+    userTimeZone: string,
   ): Promise<DailyQuestResponseDto> {
     console.log('REQUEST_USER_KEY:', request['user']);
     console.log('Full request keys:', Object.keys(request));
@@ -50,7 +51,7 @@ export class DailyQuestController {
     if (!userId) {
       throw new UnauthorizedException('User ID not found in token');
     }
-    return this.dailyQuestService.getTodaysDailyQuest(userId);
+    return this.dailyQuestService.getTodaysDailyQuest(userId, userTimeZone);
   }
 
   @Get('status')
@@ -72,11 +73,15 @@ export class DailyQuestController {
   })
   async getTodaysDailyQuestStatus(
     @ActiveUser('sub') userId: string,
+    userTimeZone: string,
   ): Promise<DailyQuestStatusDto> {
     if (!userId) {
       throw new UnauthorizedException('User ID not found in token');
     }
-    return this.dailyQuestService.getTodaysDailyQuestStatus(userId);
+    return this.dailyQuestService.getTodaysDailyQuestStatus(
+      userId,
+      userTimeZone,
+    );
   }
 
   @Post('complete')
@@ -106,10 +111,11 @@ export class DailyQuestController {
   })
   async completeDailyQuest(
     @ActiveUser('sub') userId: string,
+    userTimeZone: string,
   ): Promise<CompleteDailyQuestResponseDto> {
     if (!userId) {
       throw new UnauthorizedException('User ID not found in token');
     }
-    return this.dailyQuestService.completeDailyQuest(userId);
+    return this.dailyQuestService.completeDailyQuest(userId, userTimeZone);
   }
 }

backend/src/quests/providers/complete-daily-quest.provider.ts

@@ -5,37 +5,35 @@ import {
   NotFoundException,
 } from '@nestjs/common';
 import { InjectRepository } from '@nestjs/typeorm';
-import { Repository, DataSource } from 'typeorm';
+import { DataSource } from 'typeorm';
 import { DailyQuest } from '../entities/daily-quest.entity';
 import { User } from '../../users/user.entity';
 import { UpdateStreakProvider } from '../../streak/providers/update-streak.provider';
 import { CompleteDailyQuestResponseDto } from '../dtos/complete-daily-quest.dto';
+import { getDateString } from '../../shared/utils/date.util';
 
 @Injectable()
 export class CompleteDailyQuestProvider {
   private readonly logger = new Logger(CompleteDailyQuestProvider.name);
   private readonly BONUS_XP = 100;
 
   constructor(
-    @InjectRepository(DailyQuest)
-    private readonly dailyQuestRepository: Repository<DailyQuest>,
     @InjectRepository(User)
-    private readonly userRepository: Repository<User>,
     private readonly updateStreakProvider: UpdateStreakProvider,
     private readonly dataSource: DataSource,
   ) {}
 
-  async execute(userId: string): Promise<CompleteDailyQuestResponseDto> {
-    const todayDate = this.getTodayDateString();
+  async execute(
+    userId: string,
+    userTimeZone: string,
+  ): Promise<CompleteDailyQuestResponseDto> {
+    const todayDate = getDateString(userTimeZone, 0);
     this.logger.log(
       `Attempting to complete daily quest for user ${userId} on ${todayDate}`,
     );
 
     // Parse userId to number for streak operations
-    const userIdNumber = parseInt(userId, 10);
-    if (isNaN(userIdNumber)) {
-      throw new BadRequestException('Invalid user ID format');
-    }
+    const userIdNumber = userId;
 
     // Use transaction to ensure atomicity
     const transactionResult = await this.dataSource.transaction(
@@ -130,6 +128,7 @@ export class CompleteDailyQuestProvider {
     // 7. Update streak after transaction commits
     const streak = await this.updateStreakProvider.updateStreak(
       transactionResult.userId!,
+      userTimeZone,
     );
 
     this.logger.log(
@@ -145,14 +144,10 @@ export class CompleteDailyQuestProvider {
       streakInfo: {
         currentStreak: streak.currentStreak,
         longestStreak: streak.longestStreak,
-        lastActivityDate: streak.lastActivityDate || this.getTodayDateString(),
+        lastActivityDate:
+          streak.lastActivityDate || getDateString(userTimeZone, 0),
       },
       completedAt: transactionResult.completedAt,
     };
   }
-
-  private getTodayDateString(): string {
-    const now = new Date();
-    return now.toISOString().split('T')[0];
-  }
 }

backend/src/quests/providers/daily-quest.service.ts

@@ -14,17 +14,21 @@ export class DailyQuestService {
     private readonly completeDailyQuestProvider: CompleteDailyQuestProvider,
   ) {}
 
-  async getTodaysDailyQuest(userId: string): Promise<DailyQuestResponseDto> {
-    return this.getTodaysDailyQuestProvider.execute(userId);
+  async getTodaysDailyQuest(
+    userId: string,
+    userTimezone: string,
+  ): Promise<DailyQuestResponseDto> {
+    return this.getTodaysDailyQuestProvider.execute(userId, userTimezone);
   }
 
   /**
    * Returns the status of today's Daily Quest (read-only, lightweight)
    */
   async getTodaysDailyQuestStatus(
     userId: string,
+    userTimeZone: string,
   ): Promise<DailyQuestStatusDto> {
-    return this.getTodaysDailyQuestStatusProvider.execute(userId);
+    return this.getTodaysDailyQuestStatusProvider.execute(userId, userTimeZone);
   }
 
   /**
@@ -33,7 +37,8 @@ export class DailyQuestService {
    */
   async completeDailyQuest(
     userId: string,
+    userTimeZone: string,
   ): Promise<CompleteDailyQuestResponseDto> {
-    return this.completeDailyQuestProvider.execute(userId);
+    return this.completeDailyQuestProvider.execute(userId, userTimeZone);
   }
 }

backend/src/quests/providers/getTodaysDailyQuest.provider.ts

@@ -10,6 +10,7 @@ import { User } from '../../users/user.entity';
 import { DailyQuestResponseDto } from '../dtos/daily-quest-response.dto';
 import { PuzzleResponseDto } from '../dtos/puzzle-response.dto';
 import { PuzzleDifficulty } from '../../puzzles/enums/puzzle-difficulty.enum';
+import { getDateString } from '../../shared/utils/date.util';
 
 @Injectable()
 export class GetTodaysDailyQuestProvider {
@@ -30,8 +31,12 @@ export class GetTodaysDailyQuestProvider {
     private readonly userRepository: Repository<User>,
   ) {}
 
-  async execute(userId: string): Promise<DailyQuestResponseDto> {
-    const todayDate = this.getTodayDateString();
+  async execute(
+    userId: string,
+    userTimezone: string,
+  ): Promise<DailyQuestResponseDto> {
+    const todayDate = getDateString(userTimezone, 0);
+
     this.logger.log(`Fetching daily quest for user ${userId} on ${todayDate}`);
 
     let dailyQuest = await this.findExistingQuest(userId, todayDate);
@@ -46,11 +51,6 @@ export class GetTodaysDailyQuestProvider {
     return this.buildQuestResponse(dailyQuest);
   }
 
-  private getTodayDateString(): string {
-    const now = new Date();
-    return now.toISOString().split('T')[0];
-  }
-
   private async findExistingQuest(
     userId: string,
     questDate: string,

backend/src/quests/providers/getTodaysDailyQuestStatus.provider.ts

@@ -4,6 +4,7 @@ import { Repository } from 'typeorm';
 import { DailyQuest } from '../entities/daily-quest.entity';
 import { DailyQuestStatusDto } from '../dtos/daily-quest-status.dto';
 import { GetTodaysDailyQuestProvider } from './getTodaysDailyQuest.provider';
+import { getDateString } from '../../shared/utils/date.util';
 
 /**
  * Provider for fetching the status of today's Daily Quest.
@@ -29,8 +30,11 @@ export class GetTodaysDailyQuestStatusProvider {
    * @param userId - The user's ID
    * @returns DailyQuestStatusDto with totalQuestions, completedQuestions, isCompleted
    */
-  async execute(userId: string): Promise<DailyQuestStatusDto> {
-    const todayDate = this.getTodayDateString();
+  async execute(
+    userId: string,
+    userTimeZone: string,
+  ): Promise<DailyQuestStatusDto> {
+    const todayDate = getDateString(userTimeZone, 0);
     this.logger.log(
       `Fetching daily quest status for user ${userId} on ${todayDate}`,
     );
@@ -66,14 +70,6 @@ export class GetTodaysDailyQuestStatusProvider {
     return this.buildStatusResponse(dailyQuest);
   }
 
-  /**
-   * Returns today's date as YYYY-MM-DD string (timezone-safe)
-   */
-  private getTodayDateString(): string {
-    const now = new Date();
-    return now.toISOString().split('T')[0];
-  }
-
   /**
    * Converts DailyQuest entity to DailyQuestStatusDto
    */

backend/src/shared/utils/date.util.ts

@@ -0,0 +1,11 @@
+/**
+ * Returns a YYYY-MM-DD string in the given timezone.
+ * @param timeZone IANA timezone string (e.g. "America/New_York")
+ * @param offsetDays Number of days to offset (0 = today, -1 = yesterday)
+ */
+export function getDateString(timeZone: string, offsetDays = 0): string {
+  const now = new Date();
+  now.setDate(now.getUTCDate() + offsetDays);
+
+  return now.toLocaleDateString('en-CA', { timeZone });
+}

backend/src/streak/providers/streaks.service.ts

@@ -4,22 +4,20 @@ import { Streak } from '../entities/streak.entity';
 
 @Injectable()
 export class StreaksService {
-  constructor(
-    private readonly updateStreakProvider: UpdateStreakProvider,
-  ) {}
+  constructor(private readonly updateStreakProvider: UpdateStreakProvider) {}
 
   /**
    * Get user's current streak
    */
-  async getStreak(userId: number): Promise<Streak | null> {
+  async getStreak(userId: string): Promise<Streak | null> {
     return this.updateStreakProvider.getStreak(userId);
   }
 
   /**
    * Update streak after daily quest completion
    * Handles increment, reset, and longest streak tracking
    */
-  async updateStreak(userId: number): Promise<Streak> {
-    return this.updateStreakProvider.updateStreak(userId);
+  async updateStreak(userId: string, userTimezone: string): Promise<Streak> {
+    return this.updateStreakProvider.updateStreak(userId, userTimezone);
   }
 }