schema.ts

import fs from 'fs-extra';
import * as graphql from 'graphql/language/index.js';
import type { DocumentNode } from 'graphql/language/index.js';
import SchemaCodeGenerator from './codegen/schema.js';

export default class Schema {
  constructor(
    public document: string,
    public ast: DocumentNode,
    public filename?: string,
  ) {
    this.filename = filename;
    this.document = document;
    this.ast = ast;
  }

  codeGenerator() {
    return new SchemaCodeGenerator(this);
  }

  static async load(filename: string) {
    const document = await fs.readFile(filename, 'utf-8');
    const ast = graphql.parse(document);
    return new Schema(document, ast, filename);
  }

  static async loadFromString(document: string) {
    try {
      const ast = graphql.parse(document);
      return new Schema(document, ast);
    } catch (e) {
      throw new Error(`Failed to load schema from string: ${e.message}`);
    }
  }

  getEntityNames(): string[] {
    return this.ast.definitions
      .filter(
        def =>
          def.kind === 'ObjectTypeDefinition' &&
          def.directives?.find(directive => directive.name.value === 'entity') !== undefined,
      )
      .map(entity => (entity as graphql.ObjectTypeDefinitionNode).name.value);
  }

  immutableEntitiesCount(): number {
    const isImmutable = (entity: graphql.ConstDirectiveNode) => {
      return (
        entity.arguments?.find(arg => {
          return (
            (arg.name.value === 'immutable' || arg.name.value === 'timeseries') &&
            arg.value.kind === 'BooleanValue' &&
            arg.value.value
          );
        }) !== undefined
      );
    };

    return this.ast.definitions.filter(def => {
      if (def.kind !== 'ObjectTypeDefinition') {
        return false;
      }

      const entity = def.directives?.find(directive => directive.name.value === 'entity');
      if (entity === undefined) {
        return false;
      }

      return isImmutable(entity);
    }).length;
  }

  getImmutableEntityNames(): string[] {
    return this.ast.definitions
      .filter(
        def =>
          def.kind === 'ObjectTypeDefinition' &&
          def.directives?.find(
            directive =>
              directive.name.value === 'entity' &&
              directive.arguments?.find(arg => {
                return (
                  arg.name.value === 'immutable' &&
                  arg.value.kind === 'BooleanValue' &&
                  arg.value.value === true
                );
              }),
          ) !== undefined,
      )
      .map(entity => (entity as graphql.ObjectTypeDefinitionNode).name.value);
  }
}