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

  "type": "object",

  "properties": {
    "$schema": {
      "type": "string"
    }
  },

  "patternProperties": {
    "^[^$].*$": {
      "type": "object",
      "properties": {
        "inherit": {
          "title": "Inherit from another element",
          "description": "Most properties from the parent element will be copied onto this one",
          "type": "string"
        },

        "embedded": {
          "title": "Mark this element as belonging in the embedded content category",
          "$ref": "#/definitions/contentCategory"
        },

        "flow": {
          "title": "Mark this element as belonging in the flow content category",
          "$ref": "#/definitions/contentCategory"
        },

        "heading": {
          "title": "Mark this element as belonging in the heading content category",
          "$ref": "#/definitions/contentCategory"
        },

        "interactive": {
          "title": "Mark this element as belonging in the interactive content category",
          "$ref": "#/definitions/contentCategory"
        },

        "metadata": {
          "title": "Mark this element as belonging in the metadata content category",
          "$ref": "#/definitions/contentCategory"
        },

        "phrasing": {
          "title": "Mark this element as belonging in the phrasing content category",
          "$ref": "#/definitions/contentCategory"
        },

        "sectioning": {
          "title": "Mark this element as belonging in the sectioning content category",
          "$ref": "#/definitions/contentCategory"
        },

        "deprecated": {
          "title": "Mark element as deprecated",
          "description": "Deprecated elements should not be used. If a message is provided it will be included in the error",
          "anyOf": [
            { "type": "boolean" },
            { "type": "string" },
            { "$ref": "#/definitions/deprecatedElement" }
          ]
        },

        "foreign": {
          "title": "Mark element as foreign",
          "description": "Foreign elements are elements which have a start and end tag but is otherwize not parsed",
          "type": "boolean"
        },

        "void": {
          "title": "Mark element as void",
          "description": "Void elements are elements which cannot have content and thus must not use an end tag",
          "type": "boolean"
        },

        "transparent": {
          "title": "Mark element as transparent",
          "description": "Transparent elements follows the same content model as its parent, i.e. the content must be allowed in the parent.",
          "anyOf": [{ "type": "boolean" }, { "type": "array", "items": { "type": "string" } }]
        },

        "implicitClosed": {
          "title": "List of elements which implicitly closes this element",
          "description": "Some elements are automatically closed when another start tag occurs",
          "type": "array",
          "items": { "type": "string" }
        },

        "implicitRole": {
          "title": "Implicit ARIA role for this element",
          "description": "Some elements have implicit ARIA roles.",
          "deprecated": true,
          "function": true
        },

        "aria": {
          "title": "WAI-ARIA properties for this element",
          "$ref": "#/definitions/Aria"
        },

        "scriptSupporting": {
          "title": "Mark element as script-supporting",
          "description": "Script-supporting elements are elements which can be inserted where othersise not permitted to assist in templating",
          "type": "boolean"
        },

        "focusable": {
          "title": "Mark this element as focusable",
          "description": "This element may contain an associated label element.",
          "anyOf": [{ "type": "boolean" }, { "function": true }]
        },

        "form": {
          "title": "Mark element as a submittable form element",
          "type": "boolean"
        },

        "formAssociated": {
          "title": "Mark element as a form-associated element",
          "$ref": "#/definitions/FormAssociated"
        },

        "labelable": {
          "title": "Mark this element as labelable",
          "description": "This element may contain an associated label element.",
          "anyOf": [{ "type": "boolean" }, { "function": true }]
        },

        "submitButton": {
          "title": "Mark this element as a submit button",
          "description": "This element can be used to submit forms.",
          "anyOf": [{ "type": "boolean" }, { "function": true }]
        },

        "templateRoot": {
          "title": "Mark element as an element ignoring DOM ancestry, i.e. <template>.",
          "description": "The <template> element can contain any elements.",
          "type": "boolean"
        },

        "deprecatedAttributes": {
          "title": "List of deprecated attributes",
          "type": "array",
          "items": { "type": "string" }
        },

        "requiredAttributes": {
          "title": "List of required attributes",
          "type": "array",
          "items": { "type": "string" }
        },

        "attributes": {
          "title": "List of known attributes and allowed values",
          "$ref": "#/definitions/PermittedAttribute"
        },

        "permittedContent": {
          "title": "List of elements or categories allowed as content in this element",
          "$ref": "#/definitions/Permitted"
        },

        "permittedDescendants": {
          "title": "List of elements or categories allowed as descendants in this element",
          "$ref": "#/definitions/Permitted"
        },

        "permittedOrder": {
          "title": "Required order of child elements",
          "$ref": "#/definitions/PermittedOrder"
        },

        "permittedParent": {
          "title": "List of elements or categories allowed as parent to this element",
          "$ref": "#/definitions/Permitted"
        },

        "requiredAncestors": {
          "title": "List of required ancestor elements",
          "$ref": "#/definitions/RequiredAncestors"
        },

        "requiredContent": {
          "title": "List of required content elements",
          "$ref": "#/definitions/RequiredContent"
        },

        "textContent": {
          "title": "Allow, disallow or require textual content",
          "description": "This property controls whenever an element allows, disallows or requires text. Text from any descendant counts, not only direct children",
          "default": "default",
          "type": "string",
          "enum": ["none", "default", "required", "accessible"]
        }
      },
      "additionalProperties": false
    }
  },

  "definitions": {
    "Aria": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "implicitRole": {
          "title": "Implicit ARIA role for this element",
          "description": "Some elements have implicit ARIA roles.",
          "anyOf": [{ "type": "string" }, { "function": true }]
        },
        "naming": {
          "title": "Prohibit or allow this element to be named by aria-label or aria-labelledby",
          "anyOf": [{ "type": "string", "enum": ["prohibited", "allowed"] }, { "function": true }]
        }
      }
    },

    "contentCategory": {
      "anyOf": [{ "type": "boolean" }, { "function": true }]
    },

    "deprecatedElement": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "message": {
          "type": "string",
          "title": "A short text message shown next to the regular error message."
        },
        "documentation": {
          "type": "string",
          "title": "An extended markdown formatted message shown with the contextual rule documentation."
        },
        "source": {
          "type": "string",
          "title": "Element source, e.g. what standard or library deprecated this element.",
          "default": "html5"
        }
      }
    },

    "FormAssociated": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "disablable": {
          "type": "boolean",
          "title": "Disablable elements can be disabled using the disabled attribute."
        },
        "listed": {
          "type": "boolean",
          "title": "Listed elements have a name attribute and is listed in the form and fieldset elements property."
        }
      }
    },

    "Permitted": {
      "type": "array",
      "items": {
        "anyOf": [
          {
            "type": "string"
          },
          {
            "type": "array",
            "items": {
              "anyOf": [
                {
                  "type": "string"
                },
                {
                  "$ref": "#/definitions/PermittedGroup"
                }
              ]
            }
          },
          {
            "$ref": "#/definitions/PermittedGroup"
          }
        ]
      }
    },

    "PermittedAttribute": {
      "type": "object",
      "patternProperties": {
        "^.*$": {
          "anyOf": [
            {
              "type": "object",
              "additionalProperties": false,
              "properties": {
                "allowed": {
                  "function": true,
                  "title": "Set to a function to evaluate if this attribute is allowed in this context"
                },
                "boolean": {
                  "type": "boolean",
                  "title": "Set to true if this is a boolean attribute"
                },
                "deprecated": {
                  "title": "Set to true or string if this attribute is deprecated",
                  "oneOf": [{ "type": "boolean" }, { "type": "string" }]
                },
                "list": {
                  "type": "boolean",
                  "title": "Set to true if this attribute is a list of space-separated tokens, each which must be valid by itself"
                },
                "enum": {
                  "type": "array",
                  "title": "Exhaustive list of values (string or regex) this attribute accepts",
                  "uniqueItems": true,
                  "items": {
                    "anyOf": [{ "type": "string" }, { "regexp": true }]
                  }
                },
                "omit": {
                  "type": "boolean",
                  "title": "Set to true if this attribute can optionally omit its value"
                },
                "required": {
                  "title": "Set to true or a function to evaluate if this attribute is required",
                  "oneOf": [{ "type": "boolean" }, { "function": true }]
                }
              }
            },
            {
              "type": "array",
              "uniqueItems": true,
              "items": {
                "type": "string"
              }
            },
            {
              "type": "null"
            }
          ]
        }
      }
    },

    "PermittedGroup": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "exclude": {
          "anyOf": [
            {
              "items": {
                "type": "string"
              },
              "type": "array"
            },
            {
              "type": "string"
            }
          ]
        }
      }
    },

    "PermittedOrder": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },

    "RequiredAncestors": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },

    "RequiredContent": {
      "type": "array",
      "items": {
        "type": "string"
      }
    }
  }
}