{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "title": "Canvas Extension Manifest",
  "description": "Schema for extensions/<name>/canvas.json files",
  "type": "object",
  "required": [
    "id",
    "name",
    "description",
    "version",
    "keywords",
    "screenshots"
  ],
  "additionalProperties": false,
  "properties": {
    "id": {
      "type": "string",
      "description": "Unique identifier for the canvas extension",
      "pattern": "^[a-z0-9-]+$",
      "minLength": 1,
      "maxLength": 100
    },
    "name": {
      "type": "string",
      "description": "Display name for the extension",
      "minLength": 1,
      "maxLength": 100
    },
    "description": {
      "type": "string",
      "description": "Human-friendly description of what the extension does",
      "minLength": 1,
      "maxLength": 500
    },
    "version": {
      "type": "string",
      "description": "Semantic version of the extension metadata",
      "pattern": "^(0|[1-9]\\d*)\\.(0|[1-9]\\d*)\\.(0|[1-9]\\d*)(?:-[0-9A-Za-z-]+(?:\\.[0-9A-Za-z-]+)*)?(?:\\+[0-9A-Za-z-]+(?:\\.[0-9A-Za-z-]+)*)?$"
    },
    "author": {
      "type": "object",
      "description": "Optional author metadata",
      "required": [
        "name"
      ],
      "additionalProperties": false,
      "properties": {
        "name": {
          "type": "string",
          "minLength": 1,
          "maxLength": 100
        },
        "url": {
          "type": "string",
          "format": "uri",
          "maxLength": 2048
        }
      }
    },
    "keywords": {
      "type": "array",
      "description": "Keywords used for search and filtering",
      "items": {
        "type": "string",
        "pattern": "^[a-z0-9-]+$",
        "minLength": 1,
        "maxLength": 50
      },
      "minItems": 1,
      "maxItems": 20,
      "uniqueItems": true
    },
    "screenshots": {
      "type": "object",
      "description": "Screenshot metadata for icon and gallery cards",
      "required": [
        "icon",
        "gallery"
      ],
      "additionalProperties": false,
      "properties": {
        "icon": {
          "$ref": "#/definitions/screenshot"
        },
        "gallery": {
          "$ref": "#/definitions/screenshot"
        }
      }
    }
  },
  "definitions": {
    "screenshot": {
      "type": "object",
      "required": [
        "path",
        "type"
      ],
      "additionalProperties": false,
      "properties": {
        "path": {
          "type": "string",
          "description": "Path relative to the extension root",
          "pattern": "^assets/(?:[A-Za-z0-9_-]+/)*[A-Za-z0-9_-]+(?:\\.[A-Za-z0-9_-]+)*\\.(png|jpg|jpeg|gif|webp|svg)$",
          "minLength": 1,
          "maxLength": 200
        },
        "type": {
          "type": "string",
          "description": "MIME type for the referenced image",
          "enum": [
            "image/png",
            "image/jpeg",
            "image/gif",
            "image/webp",
            "image/svg+xml"
          ]
        }
      }
    }
  }
}