{
  "$schema": "http://json-schema.org/draft-06/schema#",
  "$id": "https://html-validate.org/schemas/config.json",

  "type": "object",
  "additionalProperties": false,
  "properties": {
    "$schema": {
      "type": "string"
    },

    "root": {
      "type": "boolean",
      "title": "Mark as root configuration",
      "description": "If this is set to true no further configurations will be searched.",
      "default": false
    },

    "extends": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "title": "Configurations to extend",
      "description": "Array of shareable or builtin configurations to extend."
    },

    "elements": {
      "type": "array",
      "items": {
        "anyOf": [{ "type": "string" }, { "type": "object" }]
      },
      "title": "Element metadata to load",
      "description": "Array of modules, plugins or files to load element metadata from. Use <rootDir> to refer to the folder with the package.json file.",
      "examples": [
        ["html-validate:recommended", "plugin:recommended", "module", "./local-file.json"]
      ]
    },

    "plugins": {
      "type": "array",
      "items": {
        "anyOf": [{ "type": "string" }, { "type": "object" }]
      },
      "title": "Plugins to load",
      "description": "Array of plugins load. Use <rootDir> to refer to the folder with the package.json file.",
      "examples": [["my-plugin", "./local-plugin"]]
    },

    "transform": {
      "type": "object",
      "additionalProperties": {
        "anyOf": [{ "type": "string" }, { "function": true }]
      },
      "title": "File transformations to use.",
      "description": "Object where key is regular expression to match filename and value is name of transformer or a function.",
      "examples": [
        {
          "^.*\\.foo$": "my-transformer",
          "^.*\\.bar$": "my-plugin",
          "^.*\\.baz$": "my-plugin:named"
        }
      ]
    },

    "rules": {
      "type": "object",
      "patternProperties": {
        ".*": {
          "anyOf": [
            { "enum": [0, 1, 2, "off", "warn", "error"] },
            {
              "type": "array",
              "minItems": 1,
              "maxItems": 1,
              "items": [{ "enum": [0, 1, 2, "off", "warn", "error"] }]
            },
            {
              "type": "array",
              "minItems": 2,
              "maxItems": 2,
              "items": [{ "enum": [0, 1, 2, "off", "warn", "error"] }, {}]
            }
          ]
        }
      },
      "title": "Rule configuration.",
      "description": "Enable/disable rules, set severity. Some rules have additional configuration like style or patterns to use.",
      "examples": [
        {
          "foo": "error",
          "bar": "off",
          "baz": ["error", { "style": "camelcase" }]
        }
      ]
    }
  }
}