import { defineConfig } from 'tsup';
import { fileURLToPath } from 'url';
import * as fs from 'fs';
import * as path from 'path';
import {csvLoader} from 'inline-schema/csv-loader/esbuild';
import {yarnSpinnerPlugin} from 'yarn-spinner-loader/esbuild';
import type { Plugin } from 'esbuild';

const srcDir = fileURLToPath(new URL('./src', import.meta.url));
const samplesDir = fileURLToPath(new URL('./src/samples', import.meta.url));

// Auto-discover samples entry points
function getSamplesEntries(): Record<string, string> {
  const entries: Record<string, string> = {};
  if (!fs.existsSync(samplesDir)) return entries;

  for (const item of fs.readdirSync(samplesDir)) {
    const fullPath = path.join(samplesDir, item);
    if (fs.statSync(fullPath).isDirectory()) {
      // Directory sample (e.g. boop) - look for index.ts
      const indexPath = path.join(fullPath, 'index.ts');
      if (fs.existsSync(indexPath)) {
        entries[item] = indexPath;
      }
    } else if (item.endsWith('.ts')) {
      // Single file sample (e.g. tic-tac-toe.ts)
      entries[item.replace('.ts', '')] = fullPath;
    }
  }
  return entries;
}

const samplesEntries = getSamplesEntries();

/**
 * Plugin to rewrite @/core/* and @/utils/* imports to use 'boardgame-core'
 */
function rewriteBoardgameImports(): Plugin {
  return {
    name: 'rewrite-boardgame-imports',
    setup(build) {
      build.onResolve({ filter: /^@\/(core|utils)\// }, args => {
        // Mark these as external and rewrite to 'boardgame-core'
        return {
          path: 'boardgame-core',
          external: true,
        };
      });
      
      // Also handle @/index imports
      build.onResolve({ filter: /^@\/index$/ }, args => {
        return {
          path: 'boardgame-core',
          external: true,
        };
      });
    },
  };
}

export default defineConfig({
  entry: samplesEntries,
  format: ['esm'],
  dts: true,
  clean: true,
  sourcemap: true,
  outDir: 'dist/samples',
  external: ['@preact/signals-core', 'mutative', 'inline-schema', 'boardgame-core'],
  esbuildPlugins: [csvLoader(), rewriteBoardgameImports(), yarnSpinnerPlugin()],
});