openapi: 3.1.0
info:
  title: HelpYourNeighbour API
  version: 0.2.0
  description: API contract for authentication, requests, offers, contacts, profile, addresses, and reviews.
servers:
  - url: http://localhost:3000
    description: Local development
security:
  - bearerAuth: []
paths:
  /health:
    get:
      tags: [system]
      summary: Health check
      security: []
      responses:
        '200':
          description: Service healthy
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HealthResponse'

  /auth/register:
    post:
      tags: [auth]
      summary: Register a new user
      security: []
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/RegisterRequest'
      responses:
        '201':
          description: User created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/AuthTokenResponse'
        '400':
          $ref: '#/components/responses/BadRequest'
        '409':
          description: Email already exists
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '500':
          description: Registration failed
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'

  /auth/login:
    post:
      tags: [auth]
      summary: Login with email/password
      security: []
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/LoginRequest'
      responses:
        '200':
          description: Login success
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/AuthTokenResponse'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          description: Invalid credentials
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'

  /requests:
    get:
      tags: [requests]
      summary: List help requests
      security: []
      responses:
        '200':
          description: Request list
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/HelpRequest'
    post:
      tags: [requests]
      summary: Create help request
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateHelpRequest'
      responses:
        '201':
          description: Created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/IdResponse'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'

  /offers/{requestId}:
    post:
      tags: [offers]
      summary: Create offer for help request
      parameters:
        - $ref: '#/components/parameters/RequestId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateOfferRequest'
      responses:
        '201':
          description: Offer created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/IdResponse'
        '400':
          $ref: '#/components/responses/BadRequestSimple'
        '401':
          $ref: '#/components/responses/Unauthorized'

  /offers/negotiation/{offerId}:
    post:
      tags: [offers]
      summary: Create counter-offer/negotiation message
      parameters:
        - $ref: '#/components/parameters/OfferId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateOfferRequest'
      responses:
        '201':
          description: Negotiation entry created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/IdResponse'
        '400':
          $ref: '#/components/responses/BadRequestSimple'
        '401':
          $ref: '#/components/responses/Unauthorized'

  /offers/accept/{offerId}:
    post:
      tags: [offers]
      summary: Accept offer and create deal
      parameters:
        - $ref: '#/components/parameters/OfferId'
      responses:
        '201':
          description: Deal created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DealCreatedResponse'
        '400':
          description: Invalid offer id
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          description: Offer not found
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'

  /contacts/request:
    post:
      tags: [contacts]
      summary: Request contact exchange for a deal
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ContactRequestCreate'
      responses:
        '201':
          description: Request created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/IdResponse'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '404':
          description: Deal not found
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '409':
          description: Request already exists
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'

  /contacts/respond:
    post:
      tags: [contacts]
      summary: Accept or reject contact exchange request
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ContactRequestRespond'
      responses:
        '200':
          description: Response processed
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/StatusResponse'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '404':
          description: Request not found
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'

  /contacts/deal/{dealId}:
    get:
      tags: [contacts]
      summary: List accepted contact exchanges for deal
      parameters:
        - $ref: '#/components/parameters/DealId'
      responses:
        '200':
          description: Accepted contact exchange rows
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/ContactExchangeRow'
        '400':
          description: Invalid dealId
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '404':
          description: Deal not found
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'

  /addresses/change-request:
    post:
      tags: [addresses]
      summary: Request address change with postal verification code
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/AddressChangeRequest'
      responses:
        '201':
          description: Change request created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/AddressChangeCreatedResponse'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'

  /addresses/verify:
    post:
      tags: [addresses]
      summary: Verify address change with 6-digit code
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/AddressVerifyRequest'
      responses:
        '200':
          description: Address verified
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/StatusResponse'
        '400':
          description: Invalid payload or code
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '404':
          description: Request not found
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '409':
          description: Request not pending
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'

  /profile/phone:
    post:
      tags: [profile]
      summary: Update encrypted phone number
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/PhoneUpdateRequest'
      responses:
        '200':
          description: Phone updated
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/StatusResponse'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'

  /reviews/{dealId}:
    post:
      tags: [reviews]
      summary: Create review for deal
      parameters:
        - $ref: '#/components/parameters/DealId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateReviewRequest'
      responses:
        '201':
          description: Review created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/IdResponse'
        '400':
          $ref: '#/components/responses/BadRequestSimple'
        '401':
          $ref: '#/components/responses/Unauthorized'

components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT

  parameters:
    RequestId:
      name: requestId
      in: path
      required: true
      schema:
        type: integer
        minimum: 1
    OfferId:
      name: offerId
      in: path
      required: true
      schema:
        type: integer
        minimum: 1
    DealId:
      name: dealId
      in: path
      required: true
      schema:
        type: integer
        minimum: 1

  responses:
    BadRequest:
      description: Validation failed
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
    BadRequestSimple:
      description: Invalid payload
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
    Unauthorized:
      description: Missing or invalid token
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
    Forbidden:
      description: Forbidden
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'

  schemas:
    HealthResponse:
      type: object
      additionalProperties: false
      properties:
        status:
          type: string
          example: ok
      required: [status]

    ErrorResponse:
      type: object
      properties:
        error:
          oneOf:
            - type: string
            - type: object

    StatusResponse:
      type: object
      additionalProperties: false
      properties:
        status:
          type: string
      required: [status]

    IdResponse:
      type: object
      additionalProperties: false
      properties:
        id:
          type: integer
          minimum: 1
      required: [id]

    DealCreatedResponse:
      type: object
      additionalProperties: false
      properties:
        dealId:
          type: integer
          minimum: 1
      required: [dealId]

    AuthTokenResponse:
      type: object
      additionalProperties: false
      properties:
        token:
          type: string
      required: [token]

    RegisterRequest:
      type: object
      additionalProperties: false
      properties:
        email:
          type: string
          format: email
        password:
          type: string
          minLength: 8
        displayName:
          type: string
          minLength: 2
          maxLength: 120
      required: [email, password, displayName]

    LoginRequest:
      type: object
      additionalProperties: false
      properties:
        email:
          type: string
          format: email
        password:
          type: string
          minLength: 1
      required: [email, password]

    HelpRequest:
      type: object
      properties:
        id:
          type: integer
        title:
          type: string
        description:
          type: string
        value_chf:
          type: number
        status:
          type: string
        created_at:
          type: string
          format: date-time
        requester_name:
          type: string

    CreateHelpRequest:
      type: object
      additionalProperties: false
      properties:
        title:
          type: string
          minLength: 3
          maxLength: 180
        description:
          type: string
          minLength: 5
        valueChf:
          type: number
          exclusiveMinimum: 0
      required: [title, description, valueChf]

    CreateOfferRequest:
      type: object
      additionalProperties: false
      properties:
        amountChf:
          type: number
          exclusiveMinimum: 0
        message:
          type: string
          maxLength: 2000
      required: [amountChf]

    ContactRequestCreate:
      type: object
      additionalProperties: false
      properties:
        dealId:
          type: integer
          minimum: 1
        targetUserId:
          type: integer
          minimum: 1
      required: [dealId, targetUserId]

    ContactRequestRespond:
      type: object
      additionalProperties: false
      properties:
        requestId:
          type: integer
          minimum: 1
        accept:
          type: boolean
      required: [requestId, accept]

    ContactExchangeRow:
      type: object
      properties:
        id:
          type: integer
        requester_id:
          type: integer
        target_id:
          type: integer
        accepted:
          type: boolean
        requester_phone_encrypted:
          type: string
        target_phone_encrypted:
          type: string

    AddressChangeRequest:
      type: object
      additionalProperties: false
      properties:
        newAddress:
          type: string
          minLength: 10
      required: [newAddress]

    AddressChangeCreatedResponse:
      type: object
      additionalProperties: false
      properties:
        requestId:
          type: integer
          minimum: 1
        postalDispatch:
          type: string
          example: pending_letter
        note:
          type: string
        verificationCode:
          type: string
          pattern: '^\\d{6}$'
      required: [requestId, postalDispatch, note, verificationCode]

    AddressVerifyRequest:
      type: object
      additionalProperties: false
      properties:
        requestId:
          type: integer
          minimum: 1
        code:
          type: string
          pattern: '^\\d{6}$'
      required: [requestId, code]

    PhoneUpdateRequest:
      type: object
      additionalProperties: false
      properties:
        phone:
          type: string
          minLength: 6
          maxLength: 40
      required: [phone]

    CreateReviewRequest:
      type: object
      additionalProperties: false
      properties:
        revieweeId:
          type: integer
          minimum: 1
        rating:
          type: integer
          minimum: 1
          maximum: 5
        comment:
          type: string
          maxLength: 2000
      required: [revieweeId, rating]