openapi: 3.0.3
info:
  title: WASAPhoto API
  description: |-
    Keep in touch with your friends by sharing photos of special moments, thanks to WASAPhoto! You can
    upload your photos directly from your PC, and they will be visible to everyone following you.
  version: "2.0.0"
paths:
  /session:
    post:
      tags: ["login"]
      summary: Logs in the user
      description: |-
        If the user does not exist, it will be created,
        and an identifier is returned.
        If the user exists, the user identifier is returned.
      operationId: doLogin
      requestBody:
        $ref: "#/components/requestBodies/userDetails"
      responses:
        '201':
          description: User log-in action successful.
          content:
            application/json:
              schema:
                type: object
                properties:
                  user_id: #todo parameter name
                    $ref: "#/components/schemas/uid"
  
  /users/{user_id}/username:
    put:
      tags: ["username"]
      summary: Updates the username
      description: Changes the username of the user with the given one.
      operationId: setMyUsername
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the user to change the username to.
      security:
        - BearerAuth: []
      requestBody:
        $ref: "#/components/requestBodies/userDetails"
      responses:
        '200':
          description: Update username action successful.
        '409':
          description: The chosen username is already taken by another user.
        '404':
          description: The user does not exist.

  /users/{user_id}/followers:
    get:
      tags: ["followers"]
      summary: Gets user's followers
      description: Get the followers list of the user
      operationId: getUserFollowers
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the user to follow.
      responses:
        '200':
          description: Returns the user list
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: "#/components/schemas/uid_name"
        '404':
          description: The user does not exist.
  /users/{user_id}/following:
    get:
      tags: ["followers"]
      summary: Gets following users
      description: Get the users that a user is following
      operationId: getUserFollowing
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the user to follow.
      responses:
        '200':
          description: Returns the user list
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: "#/components/schemas/uid_name"
        '404':
          description: The user does not exist.

  /users/{user_id}/followers/{follower_uid}:
    put:
      tags: ["followers"]
      summary: Follows a user
      description: Starts following a user
      operationId: followUser
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the user to follow.
        - name: follower_uid
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The new follower's user ID.
      responses:
        '200':
          description: Follow user action successful.
        '403':
          description: The user has no permission perform this action.
        '404':
          description: The user does not exist.
    delete:
      tags: ["followers"]
      summary: Unfollows a user
      description: Stops following a user
      operationId: unfollowUser
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the user to remove a follower from.
        - name: follower_uid
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the follower to remove.
      responses:
        '200':
          description: Unfollow user action successful.
        '404':
          description: The user is not followed by follower_uid, or the user does not exist.

  /users/{user_id}/bans/{ban_uid}:
    put:
      tags: ["bans"]
      summary: Bans a user
      description: Add a user to the list of banned users of the user.
      operationId: banUser
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the banning user.
        - name: ban_uid
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the user to ban.
      responses:
        '200':
          description: Ban user action successful.
        '403':
          description: The user has no permission to perform this action.
        '404':
          description: The user does not exist.

    delete:
      tags: ["bans"]
      summary: Unbans a user
      description: Removes a ban from the list of banned users of the user.
      operationId: unbanUser
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the unbanning user.
        - name: ban_uid
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the user to unban.
      responses:
        '200':
          description: Unban user action successful.
        '403':
          description: The user has no permission to perform this action.
        '404':
          description: The user is not banned by the user.

  /users/{user_id}/photos/{photo_id}/likes:
    get:
      tags: ["likes"]
      summary: Gets photo likes
      description: Get the list of users liking a photo
      operationId: getPhotoLikes
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The ID of the author of the photo.
        - name: photo_id
          in: path
          schema:
            $ref: "#/components/schemas/photo_id"
          required: true
          description: The ID of the photo.
      responses:
        '200':
          description: Returns the user list
          content:
            application/json:
              schema:
                type: array
                description: An array of users liking the photo.
                items:
                  $ref: "#/components/schemas/uid_name"
        '404':
          description: The user or the photo does not exist.

  /users/{user_id}/photos/{photo_id}/likes/{liker_uid}:
    put:
      tags: ["likes"]
      summary: likes a Photo
      description: Adds a like to a photo.
      operationId: likePhoto
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the author of the photo to add a like to.
        - name: liker_uid
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the user who likes the photo.
        - name: photo_id
          in: path
          schema:
            $ref: "#/components/schemas/photo_id"
          required: true
          description: The ID of the photo to like.
      responses:
        '200':
          description: Like photo action successful.
        '403':
          description: The user has no permission to perform this action.
        '404':
          description: The user or the photo does not exists (or the author of the photo has banned the authorized user).
    delete:
      tags: ["likes"]
      summary: Unlikes a photo
      description: Removes a like from a photo
      operationId: unlikePhoto
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the author of the photo to remove a like from.
        - name: liker_uid
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the user that was liking the photo.
        - name: photo_id
          in: path
          schema:
            $ref: "#/components/schemas/photo_id"
          required: true
          description: The ID of the photo to remove a like from.
      responses:
        '200':
          description: Unlike photo action successful.
        '404':
          description: The user or photo does not exists, or the user is not liking the photo.

  /users/{user_id}:
    get:
      tags: ["profile"]
      summary: Returns user profile
      description: Returns the profile of a user, including user's photos, followers, and following users.
      operationId: getUserProfile
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          description: The user ID of the user to get the profile of.
          required: true
      responses:
        '200':
          description: Returns the profile details of the given user.
          content:
            application/json:
              schema:
                type: object
                properties:
                  username:
                    $ref: "#/components/schemas/name"
                  followers:
                    $ref: "#/components/schemas/followers_n"
                  following:
                    $ref: "#/components/schemas/following_n"
                  photos:
                    $ref: "#/components/schemas/user_photo_stream"
        '404':
          description: User not found (or the authorized user is banned).

  /users/{user_id}/photos:
    post:
      tags: ["photos"]
      summary: Uploads a photo
      description: Uploads a photo in the gallery of the authorized user.
      operationId: uploadPhoto
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The user ID of the user who uploads the photo.
      requestBody:
        content:
          image/jpeg:
            schema:
              format: binary
      responses:
        '201':
          description: Upload photo action successful.
        '404':
          description: User not found (or the authorized user is banned).

  /users/{user_id}/photos/{photo_id}:
    get:
      tags: ["photos"]
      summary: Downloads a photo
      description: Returns the requested photo in binary format.
      operationId: getUserPhoto
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          description: The user ID of the user who owns the photo.
          required: true
        - name: photo_id
          in: path
          schema:
            $ref: "#/components/schemas/photo_id"
          description: The ID of the photo to download.
          required: true
      responses:
        '200':
          description: The requested photo in binary format.
          content:
            image/jpeg:
              schema:
                format: binary
        '404':
          description: User or photo not found (or the authorized user is banned by the author of the photo).
    delete:
      tags: ["photos"]
      summary: Deletes a photo
      description: Deletes a photo in the gallery of the authorized user.
      operationId: deletePhoto
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          description: The user ID of the user who deletes the photo.
          required: true
        - name: photo_id
          in: path
          schema:
            $ref: "#/components/schemas/photo_id"
          description: The ID of the photo to delete.
          required: true
      responses:
        '200':
          description: Delete photo action successful.
        '401':
          description: The user has no permission to delete that photo.
        '404':
          description: User or photo not found.

  /users/{user_id}/photos/{photo_id}/comments:
    get:
      tags: ["comments"]
      summary: Gets photo comments
      description: Gets the list of comments of a photo
      operationId: getPhotoComments
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
          description: The ID of the author of the photo.
        - name: photo_id
          in: path
          schema:
            $ref: "#/components/schemas/photo_id"
          required: true
          description: The ID of the photo.
      responses:
        '200':
          description: Returns the comments list
          content:
            application/json:
              schema:
                type: array
                description: An array of comments.
                items:
                  type: object
                  properties:
                    user_id:
                      $ref: "#/components/schemas/uid"
                    name:
                      $ref: "#/components/schemas/name"
                    comment:
                      $ref: "#/components/schemas/comment"
                    date:
                      $ref: "#/components/schemas/upload_time"
        '404':
          description: The user or the photo does not exist.
    post:
      tags: ["comments"]
      summary: Comments a photo
      description: Adds a comment to a photo.
      operationId: commentPhoto
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
        - name: photo_id
          in: path
          schema:
            $ref: "#/components/schemas/photo_id"
          required: true
      requestBody:
        description: The comment to post.
        content:
          application/json:
            schema:
              type: object
              properties:
                comment:
                  $ref: "#/components/schemas/comment"
      responses:
        '200':
          description: Comment photo action successful.
        '404':
          description: The user or the photo does not exists (or the author of the photo has banned the authorized user).

  /users/{user_id}/photos/{photo_id}/comments/{comment_id}:
    delete:
      tags: ["comments"]
      summary: Deletes a comment
      description: Deletes a photo in the gallery of the authorized user.
      operationId: deleteComment
      security:
        - BearerAuth: []
      parameters:
        - name: user_id
          in: path
          schema:
            $ref: "#/components/schemas/uid"
          required: true
        - name: photo_id
          in: path
          schema:
            $ref: "#/components/schemas/photo_id"
          required: true
        - name: comment_id
          in: path
          schema:
            $ref: "#/components/schemas/comment_id"
          required: true
      responses:
        '200':
          description: Delete comment action successful.
        '401':
          description: The user has no permission to delete that comment.
        '404':
          description: The comment does not exists.

  /stream: #todo path
    get:
      tags: ["stream"]
      summary: Returns user stream
      description: Returns the photo stream of the authorized user.
      operationId: getMyStream
      security:
        - BearerAuth: []
      parameters:
          - name: limit
            in: query
            schema:
              type: integer
              default: 25
            description: The number of elements to show.
            required: false
          - name: startIndex
            in: query
            schema:
              type: integer
              default: 0
            description: The starting offset.
            required: false
      responses:
        '200':
          description: The photo stream.
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/photo_stream"


components:
  securitySchemes:
    BearerAuth:
      type: http
      scheme: bearer

  schemas:
    uid_name:
      type: object
      properties:
        user_id:
          $ref: "#/components/schemas/uid"
        name:
          $ref: "#/components/schemas/name"
    uid:
      type: string
      format: uuid
      example: "1b4e28ba-2fa1-11d2-883f-0016d3cca427"
    name:
      type: string
      example: Maria
      pattern: 'ˆ.*?$'
      minLength: 3
      maxLength: 16
    photo_id:
      type: integer
      description: The ID of the photo.
      example: 1527
    comment_id:
      type: integer
      description: The ID of the comment.
      example: 3
    upload_time:
      type: string
      format: date-time
      description: Upload time and date.
    likes:
      type: integer
      example: 90
      description: Number of likes.
    followers_n:
      type: integer
      example: 420
      description: Number of followers.
    following_n:
      type: integer
      example: 69
      description: Number of following users.
    user_photo_stream:
      type: array
      items:
        type: object
        properties:
          photo_id:
            $ref: "#/components/schemas/photo_id"
          upload_time:
            $ref: "#/components/schemas/upload_time"
          likes:
            $ref: "#/components/schemas/likes"
    photo_stream:
      type: array
      items:
        type: object
        properties:
          user_id:
            $ref: "#/components/schemas/uid"
          username:
            $ref: "#/components/schemas/name"
          photo_id:
            $ref: "#/components/schemas/photo_id"
          upload_time:
            $ref: "#/components/schemas/upload_time"
          likes:
            $ref: "#/components/schemas/likes"
    comment:
      type: string
      example: "What a lovely picture! 😊"
      description: The comment's text

  requestBodies:
    userDetails:
      description: User details
      content:
        application/json:
          schema:
            type: object
            properties:
              name:
                $ref: "#/components/schemas/name"
      required: true