openapi: 3.1.0
info:
  title: Renamer Extension Command API
  version: 0.1.0
  description: >
    Contract representation of the `renamer extension` command workflows (preview/apply/undo)
    for testing harnesses and documentation parity.
servers:
  - url: cli://renamer
    description: Command-line invocation surface
paths:
  /extension/preview:
    post:
      summary: Preview extension normalization results
      description: Mirrors `renamer extension [source-ext...] [target-ext] --dry-run`
      operationId: previewExtension
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ExtensionRequest'
      responses:
        '200':
          description: Successful preview
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ExtensionPreview'
        '400':
          description: Validation error (invalid extensions, missing arguments)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
  /extension/apply:
    post:
      summary: Apply extension normalization
      description: Mirrors `renamer extension [source-ext...] [target-ext] --yes`
      operationId: applyExtension
      requestBody:
        required: true
        content:
          application/json:
            schema:
              allOf:
                - $ref: '#/components/schemas/ExtensionRequest'
                - type: object
                  properties:
                    dryRun:
                      type: boolean
                      const: false
      responses:
        '200':
          description: Successful apply (may include no-change entries)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ExtensionApplyResult'
        '409':
          description: Conflict detected; apply refused
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ConflictResponse'
        '400':
          description: Validation error (invalid extensions, missing arguments)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
  /extension/undo:
    post:
      summary: Undo the most recent extension batch
      description: Mirrors `renamer undo` when last ledger entry was from extension command.
      operationId: undoExtension
      responses:
        '200':
          description: Undo succeeded and ledger updated
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UndoResult'
        '409':
          description: Ledger inconsistent or missing entry
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
components:
  schemas:
    ExtensionRequest:
      type: object
      required:
        - workingDir
        - sourceExtensions
        - targetExtension
      properties:
        workingDir:
          type: string
          description: Absolute path for command scope.
        sourceExtensions:
          type: array
          description: Ordered list of dot-prefixed extensions to normalize (case-insensitive uniqueness).
          minItems: 1
          items:
            type: string
            pattern: '^\\.[\\w\\-]+$'
        targetExtension:
          type: string
          description: Dot-prefixed extension applied to all matches.
          pattern: '^\\.[\\w\\-]+$'
        includeDirs:
          type: boolean
          default: false
        recursive:
          type: boolean
          default: false
        includeHidden:
          type: boolean
          default: false
        extensionFilter:
          type: array
          items:
            type: string
            pattern: '^\\.[\\w\\-]+$'
        dryRun:
          type: boolean
          default: true
        autoConfirm:
          type: boolean
          default: false
    ExtensionPreview:
      type: object
      required:
        - totalCandidates
        - totalChanged
        - noChange
        - entries
      properties:
        totalCandidates:
          type: integer
          minimum: 0
        totalChanged:
          type: integer
          minimum: 0
        noChange:
          type: integer
          minimum: 0
        conflicts:
          type: array
          items:
            $ref: '#/components/schemas/Conflict'
        warnings:
          type: array
          items:
            type: string
        entries:
          type: array
          items:
            $ref: '#/components/schemas/PreviewEntry'
    ExtensionApplyResult:
      type: object
      required:
        - totalApplied
        - noChange
        - ledgerEntryId
      properties:
        totalApplied:
          type: integer
          minimum: 0
        noChange:
          type: integer
          minimum: 0
        ledgerEntryId:
          type: string
        warnings:
          type: array
          items:
            type: string
    UndoResult:
      type: object
      required:
        - restored
        - ledgerEntryId
      properties:
        restored:
          type: integer
        ledgerEntryId:
          type: string
        message:
          type: string
    Conflict:
      type: object
      required:
        - originalPath
        - proposedPath
        - reason
      properties:
        originalPath:
          type: string
        proposedPath:
          type: string
        reason:
          type: string
          enum:
            - duplicate_target
            - existing_file
    PreviewEntry:
      type: object
      required:
        - originalPath
        - proposedPath
        - status
      properties:
        originalPath:
          type: string
        proposedPath:
          type: string
        status:
          type: string
          enum:
            - changed
            - no_change
            - skipped
        sourceExtension:
          type: string
    ErrorResponse:
      type: object
      required:
        - error
      properties:
        error:
          type: string
        remediation:
          type: string
    ConflictResponse:
      type: object
      required:
        - error
        - conflicts
      properties:
        error:
          type: string
        conflicts:
          type: array
          items:
            $ref: '#/components/schemas/Conflict'