import { SDTFEngine, createSDTFEngine } from '@specifyapp/specify-design-token-format';
import type { DeriveBuiltInParserHandlerFromDefinition } from '../../internals/createBuiltInParserDefinition.js';
import type { ToScssVariablesParserDefinition } from './definition.js';
import { SpecifyError, specifyErrors } from '../../../errors/index.js';
import { merge } from 'lodash-es';
import { convertTokens } from './convertTokens.js';
import { DEFAULT_TEMPLATE } from '../../../converters/scss/utils/template.js';

export const toScssVariablesHandler: DeriveBuiltInParserHandlerFromDefinition<
  ToScssVariablesParserDefinition
> = async (previousDataBox, toolbox, parserOptions, outputOptions, _context) => {
  let sdtfEngine: SDTFEngine;

  switch (previousDataBox.type) {
    case 'SDTF': {
      sdtfEngine = createSDTFEngine(previousDataBox.graph);
      break;
    }
    case 'SDTF Engine': {
      sdtfEngine = previousDataBox.engine;
      break;
    }
    default: {
      throw new SpecifyError({
        errorKey: specifyErrors.PARSERS_ENGINE_INVALID_PARSER_INPUT.errorKey,
        publicMessage: `${
          (previousDataBox as any).type
        } is not a valid input for the to-css-custom-properties parser.`,
      });
    }
  }

  if (outputOptions?.type !== 'file')
    throw new SpecifyError({
      errorKey: specifyErrors.PARSERS_ENGINE_INVALID_OUTPUT_TYPE.errorKey,
      publicMessage: `The output type ${outputOptions?.type} is not supported by the to-scss-variable parser.`,
    });

  const defaultOptions = {
    tokenNameTemplate: DEFAULT_TEMPLATE,
    shouldRenderSingleMode: false,
  };

  const finalOptions = merge(defaultOptions, parserOptions);

  toolbox.populateOutput({
    type: 'files',
    files: [
      {
        path: outputOptions.filePath,
        content: { type: 'text', text: convertTokens(sdtfEngine, finalOptions) },
      },
    ],
  });

  return {
    type: 'SDTF Engine',
    engine: sdtfEngine,
  };
};