fix: build system

.browserslistrc

@@ -0,0 +1,3 @@
+current node
+last 2 versions and > 2%
+ie > 10

build/rollup.config.js

@@ -1,18 +1,165 @@
-import commonjs from '@rollup/plugin-commonjs'; // Convert CommonJS modules to ES6
-import vue from 'rollup-plugin-vue'; // Handle .vue SFC files
-import buble from '@rollup/plugin-buble'; // Transpile/polyfill with reasonable browser support
-export default {
-    input: 'src/wrapper.js', // Path relative to package.json
+// rollup.config.js
+import fs from 'fs';
+import path from 'path';
+import vue from 'rollup-plugin-vue';
+import alias from '@rollup/plugin-alias';
+import commonjs from '@rollup/plugin-commonjs';
+import replace from '@rollup/plugin-replace';
+import babel from 'rollup-plugin-babel';
+import { terser } from 'rollup-plugin-terser';
+import minimist from 'minimist';
+import scss from 'rollup-plugin-scss';      // handles '.css' and '.scss'
+
+// Get browserslist config and remove ie from es build targets
+const esbrowserslist = fs
+  .readFileSync('./.browserslistrc')
+  .toString()
+  .split('\n')
+  .filter(entry => entry && entry.substring(0, 2) !== 'ie');
+
+const argv = minimist(process.argv.slice(2));
+
+const projectRoot = path.resolve(__dirname, '..');
+
+const baseConfig = {
+  input: 'src/entry.js',
+  plugins: {
+    preVue: [
+      alias({
+        resolve: ['.js', '.jsx', '.ts', '.tsx', '.vue'],
+        entries: {
+          '@': path.resolve(projectRoot, 'src')
+        }
+      })
+    ],
+    replace: {
+      'process.env.NODE_ENV': JSON.stringify('production'),
+      'process.env.ES_BUILD': JSON.stringify('false')
+    },
+    vue: {
+      css: true,
+      template: {
+        isProduction: true
+      }
+    },
+    babel: {
+      exclude: 'node_modules/**',
+      runtimeHelpers: true,
+      extensions: ['.js', '.jsx', '.ts', '.tsx', '.vue']
+    }
+  }
+};
+
+// ESM/UMD/IIFE shared settings: externals
+// Refer to https://rollupjs.org/guide/en/#warning-treating-module-as-external-dependency
+const external = [
+  // list external dependencies, exactly the way it is written in the import statement.
+  // eg. 'jquery'
+  // 'vue'
+];
+
+// UMD/IIFE shared settings: output.globals
+// Refer to https://rollupjs.org/guide/en#output-globals for details
+const globals = {
+  // Provide global variable names to replace your external imports
+  // eg. jquery: '$'
+  // vue: 'Vue'
+};
+
+// Customize configs for individual targets
+const buildFormats = [];
+if (!argv.format || argv.format === 'es') {
+  const esConfig = {
+    ...baseConfig,
+    external,
     output: {
-        name: 'Eplainer',
-        exports: 'named',
+      file: 'dist/vue-png-explainer.esm.js',
+      format: 'esm',
+      exports: 'named'
     },
     plugins: [
-        commonjs(),
-        vue({
-            css: true, // Dynamically inject css as a <style> tag
-            compileTemplate: true, // Explicitly convert template to render function
-        }),
-        buble(), // Transpile to ES5
-    ],
-};
+      replace({
+        ...baseConfig.plugins.replace,
+        'process.env.ES_BUILD': JSON.stringify('true')
+      }),
+      ...baseConfig.plugins.preVue,
+      vue(baseConfig.plugins.vue),
+      babel({
+        ...baseConfig.plugins.babel,
+        presets: [
+          [
+            '@babel/preset-env',
+            {
+              targets: esbrowserslist
+            }
+          ]
+        ]
+      }),
+      commonjs(),
+      scss()
+    ]
+  };
+  buildFormats.push(esConfig);
+}
+
+if (!argv.format || argv.format === 'cjs') {
+  const umdConfig = {
+    ...baseConfig,
+    external,
+    output: {
+      compact: true,
+      file: 'dist/vue-png-explainer.ssr.js',
+      format: 'cjs',
+      name: 'DiscoComponents',
+      exports: 'named',
+      globals
+    },
+    plugins: [
+      replace(baseConfig.plugins.replace),
+      ...baseConfig.plugins.preVue,
+      vue({
+        ...baseConfig.plugins.vue,
+        template: {
+          ...baseConfig.plugins.vue.template,
+          optimizeSSR: true
+        }
+      }),
+      babel(baseConfig.plugins.babel),
+      commonjs(),
+      scss()
+    ]
+  };
+  buildFormats.push(umdConfig);
+}
+
+if (!argv.format || argv.format === 'iife') {
+  const unpkgConfig = {
+    ...baseConfig,
+    external,
+    output: {
+      compact: true,
+      file: 'dist/vue-png-explainer.min.js',
+      format: 'iife',
+      name: 'DiscoComponents',
+      exports: 'named',
+      globals
+    },
+    plugins: [
+      replace(baseConfig.plugins.replace),
+      ...baseConfig.plugins.preVue,
+      vue(baseConfig.plugins.vue),
+      babel(baseConfig.plugins.babel),
+      commonjs(),
+      terser({
+        output: {
+          ecma: 5
+        }
+      }),
+      scss()
+    ]
+  };
+  buildFormats.push(unpkgConfig);
+}
+
+// Export config
+export default buildFormats;