#!/usr/bin/env -S node -r esm

import * as rollup from 'rollup';
import resolve from '@rollup/plugin-node-resolve';
import commonjs from '@rollup/plugin-commonjs';
import json from '@rollup/plugin-json';
import * as path from 'path';

function computeBasename(f) {
  const m = /^(.*).dist.json$/.exec(f);
  if (!m) throw new Error(`Config filename ${f} does not match pattern`);
  return m[1];
}

const [_node, _rollup_redo, mode, configJsonFilename, targetFilename] = process.argv;

const basename = computeBasename(configJsonFilename);
const config = require(`${process.cwd()}/${configJsonFilename}`);
const inputFile = ('input' in config)
      ? path.resolve(process.cwd(), config.input)
      : `${process.cwd()}/lib/${basename}.js`;

async function build() {
  const bundle = await rollup.rollup({
    input: inputFile,
    external: ['crypto'],
    plugins: [
      {
        resolveId(toResolve, referencingModule) {
          {
            const m = /^@syndicate-lang\/(.*)$/.exec(toResolve);
            if (m) {
              if (mode === 'deps') {
                console.log(`../${m[1]}/all`);
              }
            }
          }
          if (/^\0?util(\?commonjs.*)?$/.test(toResolve)) {
            return '../core/src/util_stub.js';
          }
          if (/^\0?crypto(\?commonjs.*)?$/.test(toResolve)) {
            return '../core/src/crypto_stub.js';
          }
          if (/^\0?worker_threads(\?commonjs.*)?$/.test(toResolve)) {
            return '../core/src/worker_stub.js';
          }
          return null;
        },
      },
      resolve({
        browser: true,
      }),
      commonjs(),
      json(),
    ],
    onwarn(w, defaultHandler) {
      if (((w.code === 'UNRESOLVED_IMPORT') ||
           (w.code === 'MISSING_GLOBAL_NAME')) &&
          (w.source.startsWith('@syndicate-lang/')))
      {
        return;
      }
      defaultHandler(w);
    },
    treeshake: {
      moduleSideEffects: "no-external",
    },
  });

  switch (mode) {
    case 'deps': {
      const deps = {};
      for (const m of bundle.cache.modules) {
        deps[m.id] = m.dependencies;
      }
      const seen = {};
      function visit(id) {
        if (id in seen) return;
        if (!id.startsWith('/')) return;
        seen[id] = true;
        console.log(id);
        for (const dep of (deps[id] || [])) {
          visit(dep);
        }
      }
      visit(inputFile);
    }

    case 'generate': {
      await bundle.write({
        output: {
          file: targetFilename,
          format: config.format || 'es',
          name: config.name || 'Syndicate_' + basename,
        },
      });
      break;
    }

    default:
      console.error('Unknown mode', mode);
      break;
  }
}

build().then(null, console.error);