openapi: 3.0.0
info:
  title: Api
  version: 0.0.0
servers:
  - url: "http://localhost:8080"
paths:
  /purchases/packs/<packId>:
    post:
      tags:
        - PurchasesApiV2
      summary: createPackPurchase
      description: "POST /api/v2/purchases/packs/{packId}\nCreate purchase intent for a pack\nReturns purchase info including payment URL for YooKassa"
      operationId: createPackPurchase
      parameters:
        - name: packId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /purchases/packs/<packId>/status:
    get:
      tags:
        - PurchasesApiV2
      summary: getPackPurchaseStatus
      description: "GET /api/v2/purchases/packs/{packId}/status\nCheck if pack is purchased by the authenticated user"
      operationId: getPackPurchaseStatus
      parameters:
        - name: packId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /purchases/payments:
    post:
      tags:
        - PurchasesApiV2
      summary: createPayment
      description: POST /api/v2/purchases/payments\nCreate a payment\nCurrently supports YooKassa for web payments
      operationId: createPayment
      responses:
        200:
          description: "Operation completed!"
  /purchases/payments/<paymentId>/verify:
    get:
      tags:
        - PurchasesApiV2
      summary: verifyPayment
      description: "GET /api/v2/purchases/payments/{paymentId}/verify\nVerify payment status\nUpdates user purchases on success"
      operationId: verifyPayment
      parameters:
        - name: paymentId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /users/me:
    get:
      tags:
        - UsersApiV2
      summary: getCurrentUser
      description: GET /api/v2/users/me\nReturns current authenticated user.
      operationId: getCurrentUser
      responses:
        200:
          description: "Operation completed!"
    patch:
      tags:
        - UsersApiV2
      summary: updateCurrentUser
      description: PATCH /api/v2/users/me\nUpdates mutable user fields (currently name and email).
      operationId: updateCurrentUser
      responses:
        200:
          description: "Operation completed!"
  /users/me/settings:
    post:
      tags:
        - UsersApiV2
      summary: updateUserSettings
      description: POST /api/v2/users/me/settings\nUpdates user settings.
      operationId: updateUserSettings
      responses:
        200:
          description: "Operation completed!"
  /users/me/statistics:
    post:
      tags:
        - UsersApiV2
      summary: addUserTestStatistics
      description: POST /api/v2/users/me/statistics\nAdds user test statistics entry.
      operationId: addUserTestStatistics
      responses:
        200:
          description: "Operation completed!"
  /users/me/purchases:
    get:
      tags:
        - UsersApiV2
      summary: getUserPurchases
      description: GET /api/v2/users/me/purchases\nReturns current user's processed purchases.
      operationId: getUserPurchases
      responses:
        200:
          description: "Operation completed!"
  /users/me/statistics/detailed:
    get:
      tags:
        - UsersApiV2
      summary: getDetailedStatistics
      description: "GET /api/v2/users/me/statistics/detailed\nReturns detailed user statistics including streaks, study time, achievements, word statistics, and pack progress."
      operationId: getDetailedStatistics
      security:
        - bearerAuth: []
      responses:
        200:
          description: Detailed user statistics
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UserDataDto'
              example:
                allWordsStatistics:
                  words:
                    - word: "hello"
                      correct: 10.0
                      incorrect: 2.0
                      skipped: 0.0
                      questionTypes: ["translation", "pronunciation"]
                  correct: 150.0
                  incorrect: 30.0
                  skipped: 5.0
                allTestsStatistics:
                  tests: []
                  totalAttempts: 25
                  averageScore: 0.85
                lastTimeOnline: "2024-01-15T10:30:00Z"
                totalStudyTimeMinutes: 1200
                currentStreak: 7
                longestStreak: 15
                packProgress:
                  basic_pack:
                    packId: "basic_pack"
                    totalCards: 100
                    learnedCards: 45
                    studyTimeMinutes: 300
                    lastStudyDate: "2024-01-15T09:00:00Z"
                    firstStudyDate: "2024-01-01T08:00:00Z"
                    cardAttempts: {}
                    averageAccuracy: 0.82
                studyDates:
                  - "2024-01-15T09:00:00Z"
                  - "2024-01-14T10:00:00Z"
                categoryMinutes:
                  basic: 300
                achievements:
                  - id: "streak_7"
                    title: "Week Warrior"
                    description: "Study for 7 consecutive days"
                    type: "streak7Days"
                    unlockedAt: "2024-01-15T09:00:00Z"
                    progress: 1.0
        401:
          description: Unauthorized - Authentication required
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "unauthorized"
                message: "Authentication required"
        404:
          description: User data not found
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "user_data_not_found"
        500:
          description: Internal server error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "internal_server_error"
                message: "An unexpected error occurred"
  /users/me/statistics/packs:
    get:
      tags:
        - UsersApiV2
      summary: getPacksStatistics
      description: "GET /api/v2/users/me/statistics/packs\nReturns statistics for all user packs or specific pack if packId provided."
      operationId: getPacksStatistics
      security:
        - bearerAuth: []
      parameters:
        - name: packId
          in: query
          description: Filter by specific pack ID
          required: false
          schema:
            type: string
          example: "basic_pack"
      responses:
        200:
          description: List of pack progress statistics
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/PackProgressDto'
              example:
                - packId: "basic_pack"
                  totalCards: 100
                  learnedCards: 45
                  studyTimeMinutes: 300
                  lastStudyDate: "2024-01-15T09:00:00Z"
                  firstStudyDate: "2024-01-01T08:00:00Z"
                  cardAttempts: {}
                  averageAccuracy: 0.82
                - packId: "advanced_pack"
                  totalCards: 200
                  learnedCards: 120
                  studyTimeMinutes: 600
                  lastStudyDate: "2024-01-14T15:00:00Z"
                  firstStudyDate: "2023-12-01T10:00:00Z"
                  cardAttempts: {}
                  averageAccuracy: 0.75
        401:
          description: Unauthorized - Authentication required
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "unauthorized"
                message: "Authentication required"
        500:
          description: Internal server error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "internal_server_error"
                message: "An unexpected error occurred"
  /users/me/statistics/words:
    get:
      tags:
        - UsersApiV2
      summary: getWordsStatistics
      description: "GET /api/v2/users/me/statistics/words\nReturns paginated word statistics with optional filtering."
      operationId: getWordsStatistics
      security:
        - bearerAuth: []
      parameters:
        - name: packId
          in: query
          description: Filter by specific pack ID
          required: false
          schema:
            type: string
          example: "basic_pack"
        - name: limit
          in: query
          description: Number of results per page (default 50, max 100)
          required: false
          schema:
            type: integer
            minimum: 1
            maximum: 100
            default: 50
          example: 50
        - name: offset
          in: query
          description: Pagination offset (default 0)
          required: false
          schema:
            type: integer
            minimum: 0
            default: 0
          example: 0
        - name: sortBy
          in: query
          description: Sort order - 'difficulty', 'accuracy', 'recent', or 'alphabetical' (default 'difficulty')
          required: false
          schema:
            type: string
            enum: [difficulty, accuracy, recent, alphabetical]
            default: difficulty
          example: "difficulty"
        - name: needsReview
          in: query
          description: Filter to show only words needing review (set to 'true')
          required: false
          schema:
            type: string
            enum: ["true", "false"]
          example: "false"
      responses:
        200:
          description: Paginated word statistics
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/WordStatisticsPaginatedResponse'
              example:
                words:
                  - word: "hello"
                    correct: 10.0
                    incorrect: 2.0
                    skipped: 0.0
                    questionTypes: ["translation"]
                    lastReviewed: "2024-01-15T09:00:00Z"
                    firstLearned: "2024-01-01T08:00:00Z"
                    recentAttempts: []
                    difficultyScore: 0.17
                    needsReview: false
                    packId: "basic_pack"
                  - word: "world"
                    correct: 5.0
                    incorrect: 8.0
                    skipped: 1.0
                    questionTypes: ["translation", "pronunciation"]
                    lastReviewed: "2024-01-14T10:00:00Z"
                    firstLearned: "2024-01-01T08:00:00Z"
                    recentAttempts: []
                    difficultyScore: 0.57
                    needsReview: true
                    packId: "basic_pack"
                totalCount: 45
                page: 0
                pageSize: 50
                hasMore: false
        400:
          description: Bad request - Invalid query parameters
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "bad_request"
                message: "Invalid limit parameter. Must be between 1 and 100."
        401:
          description: Unauthorized - Authentication required
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "unauthorized"
                message: "Authentication required"
        500:
          description: Internal server error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "internal_server_error"
                message: "An unexpected error occurred"
  /users/me/statistics/timeline:
    get:
      tags:
        - UsersApiV2
      summary: getTimelineStatistics
      description: "GET /api/v2/users/me/statistics/timeline\nReturns timeline statistics for study activity over a specified period."
      operationId: getTimelineStatistics
      security:
        - bearerAuth: []
      parameters:
        - name: period
          in: query
          description: Time period - 'day', 'week', 'month', or 'year' (default 'month')
          required: false
          schema:
            type: string
            enum: [day, week, month, year]
            default: month
          example: "month"
        - name: from
          in: query
          description: Start date in ISO 8601 format (overrides period if provided)
          required: false
          schema:
            type: string
            format: date-time
          example: "2024-01-01T00:00:00Z"
        - name: to
          in: query
          description: End date in ISO 8601 format (defaults to now if not provided)
          required: false
          schema:
            type: string
            format: date-time
          example: "2024-01-31T23:59:59Z"
      responses:
        200:
          description: Timeline statistics for the specified period
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TimelineStatisticsResponse'
              example:
                period: "month"
                startDate: "2024-01-01T00:00:00Z"
                endDate: "2024-01-31T23:59:59Z"
                totalDays: 31
                activeDays: 20
                totalMinutes: 1200
                averageDailyMinutes: 60.0
                currentStreak: 7
                dailyActivity:
                  "2024-01-15T00:00:00Z": 60
                  "2024-01-14T00:00:00Z": 45
                  "2024-01-13T00:00:00Z": 30
                studyDates:
                  - "2024-01-15T09:00:00Z"
                  - "2024-01-14T10:00:00Z"
                  - "2024-01-13T08:00:00Z"
        400:
          description: Bad request - Invalid date format
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "bad_request"
                message: "Invalid date format. Use ISO 8601 format (YYYY-MM-DDTHH:mm:ssZ)."
        401:
          description: Unauthorized - Authentication required
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "unauthorized"
                message: "Authentication required"
        500:
          description: Internal server error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "internal_server_error"
                message: "An unexpected error occurred"
  /users/me/sessions:
    post:
      tags:
        - UsersApiV2
      summary: recordStudySession
      description: "POST /api/v2/users/me/sessions\nRecords a study session for the user. Used to track study activity and update statistics."
      operationId: recordStudySession
      security:
        - bearerAuth: []
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/StudySessionDto'
            example:
              sessionId: "session_1234567890"
              startTime: "2024-01-15T09:00:00Z"
              endTime: "2024-01-15T09:30:00Z"
              wordsLearned: 10
              testsCompleted: 2
              accuracy: 0.85
              packId: "basic_pack"
              testId: null
      responses:
        200:
          description: Session recorded successfully
          content:
            application/json:
              schema:
                type: object
                properties:
                  result:
                    type: boolean
                    example: true
                  sessionId:
                    type: string
                    example: "session_1234567890"
              example:
                result: true
                sessionId: "session_1234567890"
        400:
          description: Bad request - Invalid session data
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "bad_request"
                message: "Invalid session data: startTime is required"
        401:
          description: Unauthorized - Authentication required
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "unauthorized"
                message: "Authentication required"
        500:
          description: Internal server error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "internal_server_error"
                message: "An unexpected error occurred"
  /users/me/achievements:
    get:
      tags:
        - UsersApiV2
      summary: getAchievements
      description: "GET /api/v2/users/me/achievements\nReturns user's achievements and progress. Includes both unlocked and locked achievements with progress indicators."
      operationId: getAchievements
      security:
        - bearerAuth: []
      responses:
        200:
          description: List of user achievements
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/AchievementDto'
              example:
                - id: "streak_7"
                  title: "Week Warrior"
                  description: "Study for 7 consecutive days"
                  iconUrl: null
                  unlockedAt: "2024-01-15T09:00:00Z"
                  type: "streak7Days"
                  progress: 1.0
                - id: "words_10"
                  title: "Word Explorer"
                  description: "Learn 10 words"
                  iconUrl: null
                  unlockedAt: "2024-01-10T08:00:00Z"
                  type: "words10Learned"
                  progress: 1.0
                - id: "streak_30"
                  title: "Monthly Master"
                  description: "Study for 30 consecutive days"
                  iconUrl: null
                  unlockedAt: null
                  type: "streak30Days"
                  progress: 0.23
        401:
          description: Unauthorized - Authentication required
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "unauthorized"
                message: "Authentication required"
        500:
          description: Internal server error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
              example:
                error: "internal_server_error"
                message: "An unexpected error occurred"
  /admin/users:
    get:
      tags:
        - AdminUsersApiV2
      summary: getUsers
      description: GET /api/v2/admin/users\nReturns list of users by optional ids.
      operationId: getUsers
      responses:
        200:
          description: "Operation completed!"
    post:
      tags:
        - AdminUsersApiV2
      summary: upsertUser
      description: POST /api/v2/admin/users\nCreates or updates user data (admin editing).
      operationId: upsertUser
      responses:
        200:
          description: "Operation completed!"
  /admin/users/ids:
    get:
      tags:
        - AdminUsersApiV2
      summary: getUserIds
      description: GET /api/v2/admin/users/ids\nReturns comma separated user ids.
      operationId: getUserIds
      responses:
        200:
          description: "Operation completed!"
  /admin/users/<userId>/purchases:
    get:
      tags:
        - AdminUsersApiV2
      summary: getUserPurchases
      description: "GET /api/v2/admin/users/<id>/purchases\nReturns user payments history."
      operationId: getUserPurchases
      parameters:
        - name: userId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /admin/users/<userId>:
    delete:
      tags:
        - AdminUsersApiV2
      summary: deleteUser
      description: "DELETE /api/v2/admin/users/<id>\nDeletes user."
      operationId: deleteUser
      parameters:
        - name: userId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /auth/oauth/google:
    post:
      tags:
        - AuthApiV2
      summary: authenticateGoogle
      description: POST /api/v2/auth/oauth/google\nAuthenticate with Google ID token
      operationId: authenticateGoogle
      responses:
        200:
          description: "Operation completed!"
  /auth/telegram/generate-code:
    post:
      tags:
        - AuthApiV2
      summary: generateTelegramCode
      description: "POST /api/v2/auth/telegram/generate-code\nGenerate a new Telegram authentication code\nCalled by the Telegram bot when user requests a code\nBody: { telegramUserId: string, telegramUsername?: string, firstName?: string, lastName?: string }"
      operationId: generateTelegramCode
      responses:
        200:
          description: "Operation completed!"
  /auth/telegram/web-code:
    post:
      tags:
        - AuthApiV2
      summary: createWebTelegramCode
      description: "POST /api/v2/auth/telegram/web-code\nGenerates a new Telegram authentication code initiated from the web app"
      operationId: createWebTelegramCode
      responses:
        200:
          description: "Operation completed!"
  /auth/telegram/claim-code:
    post:
      tags:
        - AuthApiV2
      summary: claimTelegramCode
      description: "POST /api/v2/auth/telegram/claim-code\nCalled by Telegram bot when user sends a code generated via the web app\nBody: { code: string, telegramUserId: string, telegramUsername?: string, firstName?: string, lastName?: string }"
      operationId: claimTelegramCode
      responses:
        200:
          description: "Operation completed!"
  /auth/telegram/code-status/<code>:
    get:
      tags:
        - AuthApiV2
      summary: getTelegramCodeStatus
      description: "GET /api/v2/auth/telegram/code-status/<code>\nReturns current status for a Telegram authentication code"
      operationId: getTelegramCodeStatus
      parameters:
        - name: code
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /auth/oauth/telegram:
    post:
      tags:
        - AuthApiV2
      summary: authenticateTelegram
      description: "POST /api/v2/auth/oauth/telegram\nAuthenticate with Telegram auth code from bot\nBody: { code: string }"
      operationId: authenticateTelegram
      responses:
        200:
          description: "Operation completed!"
  /auth/refresh:
    post:
      tags:
        - AuthApiV2
      summary: refreshToken
      description: POST /api/v2/auth/refresh\nRefresh access token using refresh token
      operationId: refreshToken
      responses:
        200:
          description: "Operation completed!"
  /auth/me:
    get:
      tags:
        - AuthApiV2
      summary: getCurrentUser
      description: GET /api/v2/auth/me\nGet current authenticated user (requires Bearer token)
      operationId: getCurrentUser
      responses:
        200:
          description: "Operation completed!"
  /auth/logout:
    post:
      tags:
        - AuthApiV2
      summary: logout
      description: "POST /api/v2/auth/logout\nLogout and invalidate tokens\nBody (optional): { refreshToken: string }"
      operationId: logout
      responses:
        200:
          description: "Operation completed!"
  /tests/<testId>:
    get:
      tags:
        - TestsApiV2
      summary: getTest
      description: "GET /api/v2/tests/{testId}\nGet test details by ID"
      operationId: getTest
      parameters:
        - name: testId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /tests/<testId>/results:
    post:
      tags:
        - TestsApiV2
      summary: submitTestResults
      description: "POST /api/v2/tests/{testId}/results\nSubmit test results"
      operationId: submitTestResults
      parameters:
        - name: testId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /tests/<testId>/history:
    get:
      tags:
        - TestsApiV2
      summary: getTestHistory
      description: "GET /api/v2/tests/{testId}/history\nGet test attempt history for the authenticated user\nSupports pagination via query params: ?page=1&limit=20"
      operationId: getTestHistory
      parameters:
        - name: testId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /games:
    get:
      tags:
        - GamesApiV2
      summary: getGames
      description: GET /api/v2/games\nGet all available games\nReturns list of games with metadata
      operationId: getGames
      responses:
        200:
          description: "Operation completed!"
  /games/<gameId>/assets:
    get:
      tags:
        - GamesApiV2
      summary: getGameAssets
      description: "GET /api/v2/games/{gameId}/assets\nGet game assets\nReturns game assets file (zip) or asset info"
      operationId: getGameAssets
      parameters:
        - name: gameId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /admin/discounts:
    get:
      tags:
        - DiscountsApiV2
      summary: GET /api/v2/admin/discounts
      operationId: listDiscountCampaigns
      responses:
        200:
          description: "Operation completed!"
    post:
      tags:
        - DiscountsApiV2
      summary: POST /api/v2/admin/discounts
      operationId: addDiscountCampaign
      responses:
        200:
          description: "Operation completed!"
  /admin/discounts/<id>:
    delete:
      tags:
        - DiscountsApiV2
      summary: "DELETE /api/v2/admin/discounts/{id}"
      operationId: deleteDiscountCampaign
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /subscriptions/plans:
    get:
      tags:
        - SubscriptionsApiV2
      summary: getPlans
      description: GET /api/v2/subscriptions/plans\nList available subscription plans\nReturns all available subscription plans. Authentication is optional.
      operationId: getPlans
      responses:
        200:
          description: "Operation completed!"
  /subscriptions/purchase:
    post:
      tags:
        - SubscriptionsApiV2
      summary: purchase
      description: POST /api/v2/subscriptions/purchase\nPurchase a subscription
      operationId: purchase
      responses:
        200:
          description: "Operation completed!"
  /subscriptions/status:
    get:
      tags:
        - SubscriptionsApiV2
      summary: getStatus
      description: GET /api/v2/subscriptions/status\nGet current user subscription status
      operationId: getStatus
      responses:
        200:
          description: "Operation completed!"
  /subscriptions/cancel:
    post:
      tags:
        - SubscriptionsApiV2
      summary: cancel
      description: POST /api/v2/subscriptions/cancel\nCancel user’s subscription
      operationId: cancel
      responses:
        200:
          description: "Operation completed!"
  /packs:
    get:
      tags:
        - PacksApiV2
      summary: getPacks
      description: "GET /api/v2/packs\nGet all pack previews with pagination\nQuery params: ?search=term&language=lang&page=1&limit=20"
      operationId: getPacks
      responses:
        200:
          description: "Operation completed!"
  /packs/<packId>:
    get:
      tags:
        - PacksApiV2
      summary: getPack
      description: "GET /api/v2/packs/{packId}\nGet pack details by ID\nReturns full pack details with purchase status if authenticated"
      operationId: getPack
      parameters:
        - name: packId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /packs/<packId>/buy:
    get:
      tags:
        - PacksApiV2
      summary: getPackBuyPage
      description: "GET /api/v2/packs/{packId}/buy\nReturns pack purchase details (includes rewarded ads offer when available)"
      operationId: getPackBuyPage
      parameters:
        - name: packId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /packs/<packId>/cards:
    get:
      tags:
        - PacksApiV2
      summary: getPackCards
      description: "GET /api/v2/packs/{packId}/cards\nGet all cards in a pack\nSupports pagination via query params: ?page=1&limit=20"
      operationId: getPackCards
      parameters:
        - name: packId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /packs/<packId>/cards/<cardId>/image:
    get:
      tags:
        - PacksApiV2
      summary: getCardImage
      description: "GET /api/v2/packs/{packId}/cards/{cardId}/image\nGet card image\nReturns PNG image file\n\nImages are accessible for enabled packs even without authentication\nto allow image preview in public pack listings"
      operationId: getCardImage
      parameters:
        - name: packId
          in: path
          required: true
          schema:
            type: string
        - name: cardId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /packs/<packId>/tests:
    get:
      tags:
        - PacksApiV2
      summary: getPackTests
      description: "GET /api/v2/packs/{packId}/tests\nGet tests for a pack"
      operationId: getPackTests
      parameters:
        - name: packId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /tasks:
    get:
      tags:
        - TasksApiV2
      summary: "GET /api/v2/tasks - Get tasks with optional filtering"
      operationId: getTasks
      responses:
        200:
          description: "Operation completed!"
  /tasks/<taskId>:
    get:
      tags:
        - TasksApiV2
      summary: "GET /api/v2/tasks/{taskId} - Get specific task"
      operationId: getTask
      parameters:
        - name: taskId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /tasks/<taskId>/start:
    post:
      tags:
        - TasksApiV2
      summary: "POST /api/v2/tasks/{taskId}/start - Start a task"
      operationId: startTask
      parameters:
        - name: taskId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /tasks/<taskId>/complete:
    post:
      tags:
        - TasksApiV2
      summary: "POST /api/v2/tasks/{taskId}/complete - Complete a task"
      operationId: completeTask
      parameters:
        - name: taskId
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /users/me/tasks/progress:
    get:
      tags:
        - TasksApiV2
      summary: "GET /api/v2/users/me/tasks/progress - Get user task progress"
      operationId: getUserProgress
      responses:
        200:
          description: "Operation completed!"
  /tasks/categories:
    get:
      tags:
        - TasksApiV2
      summary: "GET /api/v2/tasks/categories - Get available task categories and filters"
      operationId: getTaskCategories
      responses:
        200:
          description: "Operation completed!"
  /promocodes:
    get:
      tags:
        - PromocodesApiV2
      summary: listPromocodes
      description: GET /api/v2/promocodes\nLists available promocodes for current user.\nReturns active campaigns with promocodes that user can apply.
      operationId: listPromocodes
      responses:
        200:
          description: "Operation completed!"
  /promocodes/<code>/validate:
    get:
      tags:
        - PromocodesApiV2
      summary: validatePromocode
      description: "GET /api/v2/promocodes/{code}/validate\nValidates a promocode without applying it.\nReturns validation result with valid: true/false and message."
      operationId: validatePromocode
      parameters:
        - name: code
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /promocodes/<code>/apply:
    post:
      tags:
        - PromocodesApiV2
      summary: applyPromocode
      description: "POST /api/v2/promocodes/{code}/apply\nApplies promocode for current user."
      operationId: applyPromocode
      parameters:
        - name: code
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /admin/promocodes:
    get:
      tags:
        - PromocodesApiV2
      summary: listPromoCodeCampaigns
      description: GET /api/v2/admin/promocodes\nLists promocode campaigns (admin only).
      operationId: listPromoCodeCampaigns
      responses:
        200:
          description: "Operation completed!"
    post:
      tags:
        - PromocodesApiV2
      summary: upsertPromoCodeCampaign
      description: POST /api/v2/admin/promocodes\nCreates or updates promocode campaign (admin only).
      operationId: upsertPromoCodeCampaign
      responses:
        200:
          description: "Operation completed!"
  /admin/promocodes/<id>:
    get:
      tags:
        - PromocodesApiV2
      summary: getPromoCodeCampaign
      description: "GET /api/v2/admin/promocodes/{id}\nReturns promocode campaign details (admin only)."
      operationId: getPromoCodeCampaign
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
    delete:
      tags:
        - PromocodesApiV2
      summary: deletePromoCodeCampaign
      description: "DELETE /api/v2/admin/promocodes/{id}\nDeletes promocode campaign (admin only)."
      operationId: deletePromoCodeCampaign
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /ads/product/acquire/<key>:
    post:
      tags:
        - AdsApiV2
      summary: "POST /api/v2/ads/product/acquire/{key}"
      description: Confirms rewarded ad completion and grants product access to the user.
      operationId: acquireProductForAd
      parameters:
        - name: key
          in: path
          required: true
          schema:
            type: string
      responses:
        200:
          description: "Operation completed!"
  /adsgram/reward:
    get:
      tags:
        - AdsApiV2
      summary: "GET /api/v2/adsgram/reward?userId={userId}"
      description: Callback endpoint for Adsgram rewarded ad completion.\nThis endpoint is called by Adsgram when a user completes a rewarded ad.
      operationId: adsgramRewardCallback
      responses:
        200:
          description: "Operation completed!"
components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
      description: JWT Bearer token authentication
  schemas:
    ErrorResponse:
      type: object
      properties:
        error:
          type: string
          description: Error code identifier
          example: "bad_request"
        message:
          type: string
          description: Human-readable error message
          example: "Invalid request parameters"
      required:
        - error
    UserDataDto:
      type: object
      description: Comprehensive user statistics and data
      properties:
        allWordsStatistics:
          $ref: '#/components/schemas/AllWordsStatisticsDto'
        allTestsStatistics:
          $ref: '#/components/schemas/AllTestsStatisticsDto'
        lastTimeOnline:
          type: string
          format: date-time
          nullable: true
          description: When user was last online
        totalStudyTimeMinutes:
          type: integer
          description: Total study time in minutes
          example: 1200
        currentStreak:
          type: integer
          description: Current consecutive days streak
          example: 7
        longestStreak:
          type: integer
          description: Longest streak ever achieved
          example: 15
        packProgress:
          type: object
          additionalProperties:
            $ref: '#/components/schemas/PackProgressDto'
          description: Map of pack ID to pack progress statistics
        studyDates:
          type: array
          items:
            type: string
            format: date-time
          description: List of dates when user studied
        categoryMinutes:
          type: object
          additionalProperties:
            type: integer
          description: Study time by category/language in minutes
        achievements:
          type: array
          items:
            $ref: '#/components/schemas/AchievementDto'
          description: User's achievements
    AllWordsStatisticsDto:
      type: object
      description: Aggregated word statistics
      properties:
        words:
          type: array
          items:
            $ref: '#/components/schemas/WordStatisticsDto'
        correct:
          type: number
          format: double
          description: Total correct answers
        incorrect:
          type: number
          format: double
          description: Total incorrect answers
        skipped:
          type: number
          format: double
          description: Total skipped answers
    WordStatisticsDto:
      type: object
      description: Basic word statistics
      properties:
        word:
          type: string
          description: The word being tracked
          example: "hello"
        correct:
          type: number
          format: double
          description: Number of correct answers
          example: 10.0
        incorrect:
          type: number
          format: double
          description: Number of incorrect answers
          example: 2.0
        skipped:
          type: number
          format: double
          description: Number of skipped answers
          example: 0.0
        questionTypes:
          type: array
          items:
            type: string
          description: Types of questions attempted
          example: ["translation", "pronunciation"]
    AllTestsStatisticsDto:
      type: object
      description: Aggregated test statistics
      properties:
        tests:
          type: array
          items:
            type: object
        totalAttempts:
          type: integer
          description: Total number of test attempts
        averageScore:
          type: number
          format: double
          description: Average test score (0.0 to 1.0)
    PackProgressDto:
      type: object
      description: Statistics about user's progress on a specific pack
      properties:
        packId:
          type: string
          description: Pack identifier
          example: "basic_pack"
        totalCards:
          type: integer
          description: Total number of cards in the pack
          example: 100
        learnedCards:
          type: integer
          description: Number of cards learned by the user
          example: 45
        studyTimeMinutes:
          type: integer
          description: Total study time spent on this pack in minutes
          example: 300
        lastStudyDate:
          type: string
          format: date-time
          nullable: true
          description: Date when user last studied this pack
          example: "2024-01-15T09:00:00Z"
        firstStudyDate:
          type: string
          format: date-time
          nullable: true
          description: Date when user first started studying this pack
          example: "2024-01-01T08:00:00Z"
        cardAttempts:
          type: object
          additionalProperties:
            type: integer
          description: Map of card ID to number of attempts
          example: {}
        averageAccuracy:
          type: number
          format: double
          description: Average accuracy across all attempts (0.0 to 1.0)
          example: 0.82
      required:
        - packId
        - totalCards
    DetailedWordStatisticsDto:
      allOf:
        - $ref: '#/components/schemas/WordStatisticsDto'
        - type: object
          properties:
            lastReviewed:
              type: string
              format: date-time
              nullable: true
              description: When this word was last reviewed
            firstLearned:
              type: string
              format: date-time
              nullable: true
              description: When this word was first learned
            recentAttempts:
              type: array
              items:
                $ref: '#/components/schemas/WordAttemptDto'
              description: Recent attempts (last 10)
            difficultyScore:
              type: number
              format: double
              description: Difficulty score (0.0 = easy, 1.0 = hard)
              example: 0.57
            needsReview:
              type: boolean
              description: Whether this word needs review
              example: true
            packId:
              type: string
              nullable: true
              description: Which pack this word belongs to
              example: "basic_pack"
    WordAttemptDto:
      type: object
      description: Individual word attempt data
      properties:
        timestamp:
          type: string
          format: date-time
          description: When the attempt happened
        wasCorrect:
          type: boolean
          description: Whether the answer was correct
        questionType:
          type: string
          description: Type of question asked
          example: "translation"
        wasSkipped:
          type: boolean
          description: Whether the question was skipped
          default: false
      required:
        - timestamp
        - wasCorrect
        - questionType
    WordStatisticsPaginatedResponse:
      type: object
      description: Paginated response for word statistics
      properties:
        words:
          type: array
          items:
            $ref: '#/components/schemas/DetailedWordStatisticsDto'
          description: List of word statistics
        totalCount:
          type: integer
          description: Total number of words matching the filter
          example: 45
        page:
          type: integer
          description: Current page number (0-based)
          example: 0
        pageSize:
          type: integer
          description: Number of results per page
          example: 50
        hasMore:
          type: boolean
          description: Whether there are more results available
          example: false
      required:
        - words
        - totalCount
        - page
        - pageSize
        - hasMore
    TimelineStatisticsResponse:
      type: object
      description: Timeline statistics for study activity
      properties:
        period:
          type: string
          description: Time period used
          enum: [day, week, month, year]
          example: "month"
        startDate:
          type: string
          format: date-time
          description: Start date of the period
          example: "2024-01-01T00:00:00Z"
        endDate:
          type: string
          format: date-time
          description: End date of the period
          example: "2024-01-31T23:59:59Z"
        totalDays:
          type: integer
          description: Total days in the period
          example: 31
        activeDays:
          type: integer
          description: Number of days with study activity
          example: 20
        totalMinutes:
          type: integer
          description: Total study time in minutes
          example: 1200
        averageDailyMinutes:
          type: number
          format: double
          description: Average study time per active day in minutes
          example: 60.0
        currentStreak:
          type: integer
          description: Current streak within the period
          example: 7
        dailyActivity:
          type: object
          additionalProperties:
            type: integer
          description: Map of date (ISO string) to study minutes for that day
          example:
            "2024-01-15T00:00:00Z": 60
            "2024-01-14T00:00:00Z": 45
        studyDates:
          type: array
          items:
            type: string
            format: date-time
          description: List of dates when user studied
          example:
            - "2024-01-15T09:00:00Z"
            - "2024-01-14T10:00:00Z"
      required:
        - period
        - startDate
        - endDate
        - totalDays
        - activeDays
        - totalMinutes
        - averageDailyMinutes
        - currentStreak
        - dailyActivity
        - studyDates
    StudySessionDto:
      type: object
      description: Study session data for tracking learning activity
      properties:
        sessionId:
          type: string
          nullable: true
          description: Unique session identifier
          example: "session_1234567890"
        startTime:
          type: string
          format: date-time
          description: When the session started
          example: "2024-01-15T09:00:00Z"
        endTime:
          type: string
          format: date-time
          nullable: true
          description: When the session ended (null if still active)
          example: "2024-01-15T09:30:00Z"
        wordsLearned:
          type: integer
          description: Number of words learned during this session
          default: 0
          example: 10
        testsCompleted:
          type: integer
          description: Number of tests completed during this session
          default: 0
          example: 2
        accuracy:
          type: number
          format: double
          description: Overall accuracy during this session (0.0 to 1.0)
          default: 0.0
          example: 0.85
        packId:
          type: string
          nullable: true
          description: Pack being studied (if focused on specific pack)
          example: "basic_pack"
        testId:
          type: string
          nullable: true
          description: Test being taken (if part of a test)
      required:
        - startTime
    AchievementDto:
      type: object
      description: Achievement data structure
      properties:
        id:
          type: string
          description: Unique achievement identifier
          example: "streak_7"
        title:
          type: string
          description: Achievement title
          example: "Week Warrior"
        description:
          type: string
          description: Achievement description
          example: "Study for 7 consecutive days"
        iconUrl:
          type: string
          nullable: true
          description: URL to achievement icon/badge image
        unlockedAt:
          type: string
          format: date-time
          nullable: true
          description: When this achievement was unlocked (null if locked)
          example: "2024-01-15T09:00:00Z"
        type:
          type: string
          description: Achievement type for categorization
          enum:
            - firstWordLearned
            - firstTestCompleted
            - firstPackCompleted
            - streak3Days
            - streak7Days
            - streak30Days
            - streak100Days
            - words10Learned
            - words50Learned
            - words100Learned
            - words500Learned
            - words1000Learned
            - perfectTestScore
            - speedLearner
            - dedicatedLearner
            - nightOwl
            - earlyBird
            - consistentLearner
            - languageMaster
          example: "streak7Days"
        progress:
          type: number
          format: double
          description: Progress towards unlocking (0.0 to 1.0 for locked achievements)
          default: 0.0
          example: 1.0
      required:
        - id
        - title
        - description
        - type
tags:
  - name: PurchasesApiV2
    description: Purchases API v2\n\nRESTful endpoints for managing purchases and payments
  - name: UsersApiV2
    description: "API v2 endpoints for user profile and self-service operations."
  - name: AdminUsersApiV2
    description: Admin endpoints for user management in API v2.
  - name: AuthApiV2
    description: API v2 Authentication endpoints\n\nImplements OAuth2/JWT Bearer token authentication
  - name: TestsApiV2
    description: Tests API v2\n\nRESTful endpoints for managing tests and test results
  - name: GamesApiV2
    description: Games API v2\n\nRESTful endpoints for managing games and game assets
  - name: DiscountsApiV2
    description: Admin endpoints for discount campaign management.
  - name: SubscriptionsApiV2
    description: "Subscriptions API v2\nRESTful endpoints for managing subscriptions & plans"
  - name: PacksApiV2
    description: API v2 Packs endpoints\n\nRESTful endpoints for card packs with pagination and filtering
  - name: TasksApiV2
    description: API v2 endpoints for user tasks management
  - name: PromocodesApiV2
    description: API v2 endpoints for promocode management and activation.
  - name: AdsApiV2
    description: API v2 endpoints for rewarded ads flows.