install.json

{
  "resources": {
    "head": [
      {
        "type": "style",
        "src": "./source/app.css"
      },
      {
        "type": "script",
        "src": "./vendor/watermark.js"
      },
      {
        "type": "script",
        "src": "./source/app.js"
      }
    ]
  },
  "preview": {
    "handlers": [
      {
        "options": ["text", "textSize", "textColor", "position", "opacity"],
        "execute": "INSTALL_SCOPE.setOptions(INSTALL_OPTIONS)"
      }
    ]
  },
  "options": {
    "properties": {
      "text": {
        "order": 20,
        "default": "Sample text",
        "title": "Watermark text",
        "type": "string"
      },
      "textSize": {
        "order": 21,
        "default": "48",
        "title": "Text size",
        "type": "string",
        "enum": [
          "24",
          "48",
          "96"
        ],
        "enumNames": {
          "24": "Small",
          "48": "Medium",
          "96": "Large"
        }
      },
      "textColor": {
        "order": 22,
        "default": "#ffffff",
        "format": "color",
        "title": "Text color",
        "type": "string"
      },
      "position": {
        "order": 30,
        "default": "center",
        "title": "Watermark position",
        "type": "string",
        "enum": [
          "upperLeft",
          "upperRight",
          "lowerLeft",
          "lowerRight",
          "center"
        ],
        "enumNames": {
          "upperLeft": "Upper left corner",
          "upperRight": "Upper right corner",
          "lowerLeft": "Lower left corner",
          "lowerRight": "Lower right corner",
          "center": "Center"
        }
      },
      "opacity": {
        "order": 31,
        "default": 50,
        "title": "Watermark opacity",
        "type": "number",
        "format": "slider",
        "minimum": 0,
        "maximum": 100,
        "step": 1
      },
      "showAdvanced": {
        "order": 32,
        "type": "boolean",
        "title": "Show advanced options",
        "default": false
      },
      "advanced": {
        "showIf": {
          "showAdvanced": true
        },
        "order": 33,
        "type": "object",
        "title": "Advanced options",
        "properties": {
          "location": {
            "order": 0,
            "title": "Location",
            "type": "string",
            "format": "selector",
            "default": "body"
          },
          "minWidth": {
            "order": 1,
            "default": 300,
            "title": "Minimum width",
            "description": "Only watermark images with a minimum pixel width of...",
            "type": "number",
            "minimum": 0
          },
          "minHeight": {
            "order": 2,
            "default": 300,
            "title": "Minimum height",
            "description": "Only watermark images with a minimum pixel height of...",
            "type": "number",
            "minimum": 0
          }
        }
      }
    }
  }
}