openapi: 3.0.0
info:
  title: Usage API
  version: 1.1.0
  description: API for retrieving usage information and costs

paths:
  /v1/usage/total-cost:
    get:
      summary: Get total cost for a given period
      tags:
        - Usage
      security:
        - ApiKeyAuth: []
      parameters:
        - in: query
          name: start_date
          schema:
            type: string
            format: date
          required: true
        - in: query
          name: end_date
          schema:
            type: string
            format: date
          required: true
      responses:
        '200':
          description: Total cost retrieved successfully
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TotalCostResponse'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'

  /v1/usage/records:
    get:
      summary: Get a list of usage records for a given period
      tags:
        - Usage
      security:
        - ApiKeyAuth: []
      parameters:
        - in: query
          name: start_date
          schema:
            type: string
            format: date
          required: true
        - in: query
          name: end_date
          schema:
            type: string
            format: date
          required: true
        - $ref: '#/components/parameters/PageParam'
        - $ref: '#/components/parameters/ItemsPerPageParam'
      responses:
        '200':
          description: Usage records retrieved successfully
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    type: array
                    items:
                      $ref: '#/components/schemas/UsageRecordResponse'
                  pagination:
                    $ref: '#/components/schemas/Pagination'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'

components:
  schemas:
    TotalCostResponse:
      type: object
      properties:
        start_date:
          type: string
          format: date
        end_date:
          type: string
          format: date
        total_cost:
          type: number
          format: float

    UsageRecordResponse:
      type: object
      properties:
        id:
          type: string
          format: uuid
        created_at:
          type: string
          format: date-time
        service_name:
          type: string
          enum: [ FINE_TUNING_JOB ]
        usage_amount:
          type: number
          format: float
        usage_unit:
          type: string
          enum: [ TOKEN ]
        cost:
          type: number
          format: float
        fine_tuning_job_name:
          type: string
    Pagination:
      type: object
      properties:
        total_pages:
          type: integer
        current_page:
          type: integer
        items_per_page:
          type: integer

    ErrorResponse:
      type: object
      properties:
        status:
          type: integer
        message:
          type: string

  responses:
    BadRequest:
      description: Bad request
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'

    Unauthorized:
      description: Unauthorized
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'

    NotFound:
      description: Resource not found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'

    Forbidden:
      description: Forbidden
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'

  parameters:
    PageParam:
      in: query
      name: page
      schema:
        type: integer
        default: 1
        minimum: 1
      description: Page number to retrieve
    ItemsPerPageParam:
      in: query
      name: items_per_page
      schema:
        type: integer
        default: 20
        minimum: 1
      description: Number of items to return per page

  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: x-api-key