import { walkProgram } from '@code-to-json/core';
import { formatWalkerOutput } from '@code-to-json/formatter';
import { InvalidArgumentsError } from '@code-to-json/utils';
import { createReverseResolverForProject, NODE_HOST } from '@code-to-json/utils-node';
import { createProgramFromTsConfig, PASSTHROUGH_REVERSE_RESOLVER } from '@code-to-json/utils-ts';
import * as fs from 'fs';
import * as path from 'path';
import * as ts from 'typescript';
import { createProgramFromEntryGlobs } from '../command-utils';

/**
 * Run the symbol walker to generate a JSON file based on some code
 * @param options CLI options
 * @param entries an array of entry globs
 * @internal
 */
export default async function generateJSON(
  options: { [k: string]: any } & { project?: string },
  entries?: string[],
): Promise<void>;
export default async function generateJSON(
  options: { [k: string]: any },
  entries: string[],
): Promise<void>;
export default async function generateJSON(
  options: { [k: string]: any },
  rawEntries?: string[],
): Promise<void> {
  const { project, out = 'out', format } = options as {
    format: 'raw' | 'both' | 'formatted';
    out: string;
    project: string;
  };
  let program!: ts.Program;
  let pathNormalizer = PASSTHROUGH_REVERSE_RESOLVER;

  if (typeof project === 'string') {
    // run tool based on tsconfig.json
    program = await createProgramFromTsConfig(project, NODE_HOST);
    pathNormalizer = await createReverseResolverForProject(project, NODE_HOST);
  } else if (!project && rawEntries && rawEntries.length > 0) {
    // run tool based on entries
    program = await createProgramFromEntryGlobs(rawEntries);
  } else {
    throw new InvalidArgumentsError('Either --project <path> or entries glob(s) must be defined');
  }
  if (['raw', 'both', 'formatted'].indexOf(format) < 0) {
    throw new Error(`Invalid --format option: ${format}`);
  }
  // get the raw result
  const walkResult = walkProgram(program, NODE_HOST, {
    pathNormalizer,
  });

  const outputPath = path.isAbsolute(out) ? out : path.join(process.cwd(), out);
  if (!fs.existsSync(outputPath)) {
    fs.mkdirSync(outputPath, { recursive: true });
  }
  if (format === 'raw' || format === 'both') {
    const rawOutputPath = path.join(outputPath, 'raw.json');
    // write the raw output file
    fs.writeFileSync(rawOutputPath, JSON.stringify(walkResult, null, '  '));
  }
  if (format === 'formatted' || format === 'both') {
    // get the formatted result
    const formattedResult = formatWalkerOutput(walkResult);
    // determine the appropriate place(s) to write output files
    const formattedOutputPath = path.join(outputPath, 'formatted.json');
    // create the output folder if it doesn't currently exist
    // write the formatted output file
    fs.writeFileSync(formattedOutputPath, JSON.stringify(formattedResult, null, '  '));
  }
}