$schema: https://json-schema.org/draft/2020-12/schema
title: Deimos AST generation spec
type: object
description: Top level is a map of node names in Pascal case (e.g., CompilationUnit) to node definitions.
additionalProperties:
  $ref: "#/$defs/NodeDefinition"
$defs:
  NodeDefinition:
    type: object
    additionalProperties: false
    description: A definition of a node type.
    properties:
      children:
        type: array
        description: Ordered child fields for this node.
        items:
          $ref: "#/$defs/StructChildDefinition"
      rules:
        type: array
        description: Alternative parse rules that build this node.
        items:
          $ref: "#/$defs/EnumChildDefinition"
    oneOf:
      - required:
          - "children"
      - required:
          - "rules"
  StructChildDefinition:
    description: A definition of a node's child. Either a bare child name (string) in snake case, or an object.
    oneOf:
      - type: string
        description: Shorthand where child name, var, build, and with are inferred from the given snake-case child name.
      - $ref: "#/$defs/ChildDefinitionWrapper"
  ChildDefinitionWrapper:
    type: object
    description: Single-key object mapping the child-name to its spec.
    minProperties: 1
    maxProperties: 1
    additionalProperties: false
    patternProperties:
      "^[a-z][a-z0-9_]*$":
        $ref: "#/$defs/ChildDefinition"
  ChildDefinition:
    type: object
    description: One of skip/vec/single child specs.
    oneOf:
      - $ref: "#/$defs/SkipChildDefinition"
      - $ref: "#/$defs/VecChildDefinition"
      - $ref: "#/$defs/SingleChildDefinition"
  SkipChildDefinition:
    type: object
    additionalProperties: false
    description: A definition for a child rule that does nothing, i.e., is skipped.
    properties:
      rule:
        type: string
      skip:
        type: boolean # note: must be true
    required:
      - rule
      - skip
  VecChildDefinition:
    type: object
    additionalProperties: false
    description: A definition for a child rule that can be matched multiple times.
    properties:
      rule:
        type: string
      vec:
        type: boolean
    required:
      - rule
      - vec
  SingleChildDefinition:
    type: object
    additionalProperties: false
    description: A definition for a child rule that builds one item.
    properties:
      rule:
        type: string
        description: The type to build, in Pascal case.
      optional:
        type: boolean
        description: If true, this child will be stored as an Option.
      build:
        oneOf:
          - type: string
          - $ref: "#/$defs/SingleChildBuildDefinition"
  SingleChildBuildDefinition:
    type: object
    additionalProperties: false
    description: A definition of what exactly to build for a given child rule.
    oneOf:
      - $ref: "#/$defs/BuildSingleTypeChild"
      - $ref: "#/$defs/BuildBooleanChild"
  BuildSingleTypeChild:
    type: object
    additionalProperties: false
    description: A definition of a single-type child to build.
    properties:
      or_else:
        type: string
        description: The method name to call upon the built-type if the rule is not found. Takes precedence over "or_else_default".
      or_else_default:
        type: boolean
        description: Whether to call the default method on the built-type if the rule is not found.
  BuildBooleanChild:
    type: object
    additionalProperties: false
    description: A definition for building a boolean child.
    properties:
      type:
        type: string
        enum:
          - boolean
      on:
        type: string
        enum:
          - rule_present
  EnumChildDefinition:
    description: A definition of an enum node's child. Either a bare rule (string) in Pascal case, or an object.
    oneOf:
      - type: string
        description: Shorthand where child name, var, build, and with are inferred from the given Pascal-case rule name.
      - $ref: "#/$defs/LongEnumChildDefinition"
  LongEnumChildDefinition:
    type: object
    additionalProperties: false
    description: A format for specifying more specific information for an enum child.
    properties:
      rule:
        type: string
      build:
        type: string
    required:
      - rule
      - build