$schema: "https://json-schema.org/draft/2020-12/schema"
$id: "https://cfse.ai/schemas/artifacts/prj.schema.yaml"
title: "CFSE Projection (PRJ) Artifact Schema"
description: "Schema for PRJ-* artifacts (viewer-context projections across surfaces)"

type: object

required:
  - id
  - title
  - viewer_context
  - surfaces

properties:
  id:
    $ref: "https://cfse.ai/schemas/grammar.schema.yaml#/$defs/ProjectionID"
    description: "Unique identifier for this PRJ artifact"

  title:
    type: string
    minLength: 1
    maxLength: 120
    description: "Human-readable name"

  viewer_context:
    type: object
    description: "Viewer context definition (label + reference based; no executable logic)"
    additionalProperties: true

  surfaces:
    type: array
    minItems: 1
    items:
      $ref: "#/$defs/SurfaceRef"
    description: "Surfaces included in this projection"

  assumptions:
    type: object
    properties:
      predicates:
        type: array
        items:
          $ref: "https://cfse.ai/schemas/grammar.schema.yaml#/$defs/PredicateID"
      invariants:
        type: array
        items:
          $ref: "https://cfse.ai/schemas/grammar.schema.yaml#/$defs/InvariantID"
    additionalProperties: false
    description: "Traceability references used to define the projection context"

  visible:
    type: array
    items:
      $ref: "#/$defs/Exposure"
    description: "Optional explicit listing of what is visible for this viewer context"

  notes:
    type: string

  status:
    $ref: "https://cfse.ai/schemas/grammar.schema.yaml#/$defs/ArtifactStatus"
    default: "DRAFT"

  version:
    type: string
    pattern: "^[0-9]+\\.[0-9]+\\.[0-9]+$"

  extensions:
    $ref: "https://cfse.ai/schemas/grammar.schema.yaml#/$defs/Extensions"

additionalProperties: false

$defs:
  SurfaceRef:
    type: object
    required:
      - ref
    properties:
      ref:
        $ref: "https://cfse.ai/schemas/grammar.schema.yaml#/$defs/EntryPointID"
        description: "Reference to an entry point (EP-*)"
      notes:
        type: string
    additionalProperties: false

  ExposureMode:
    type: string
    enum:
      - DISCLOSE
      - DERIVE
      - LINK
      - METADATA

  Exposure:
    type: object
    required:
      - ref
      - exposure_mode
    properties:
      ref:
        type: string
      exposure_mode:
        $ref: "#/$defs/ExposureMode"
      governed_by_invariants:
        type: array
        items:
          $ref: "https://cfse.ai/schemas/grammar.schema.yaml#/$defs/InvariantID"
      notes:
        type: string
    additionalProperties: false