[Playground CLI] Move mounting code to mount.ts (#2362)

## Motivation for the change, related issues

Consolidates two mounting-related files to sets the stage for
#2360. Right now
it diffs two deleted files with one added file and it's difficult to
reason about.

There are no code changes other than relocating the code.

## Testing Instructions (or ideally a Blueprint)
 
CI

Author: adamziel

packages/playground/cli/src/cli-auto-mount.ts

@@ -1,3 +1,10 @@
+import { basename, join } from 'path';
+import type {
+	BlueprintDeclaration,
+	StepDefinition,
+} from '@wp-playground/blueprints';
+import fs from 'fs';
+import type { RunCLIArgs } from './run-cli';
 import { existsSync } from 'fs';
 import path from 'path';
 import { createNodeFsMountHandler } from '@php-wasm/node';
@@ -83,3 +90,185 @@ export function mountResources(php: PHP, mounts: Mount[]) {
 		php.mount(mount.vfsPath, createNodeFsMountHandler(mount.hostPath));
 	}
 }
+
+export function expandAutoMounts(args: RunCLIArgs): RunCLIArgs {
+	const path = process.cwd();
+
+	const mount = [...(args.mount || [])];
+	const mountBeforeInstall = [...(args.mountBeforeInstall || [])];
+
+	if (isPluginDirectory(path)) {
+		const pluginName = basename(path);
+		mount.push({
+			hostPath: path,
+			vfsPath: `/wordpress/wp-content/plugins/${pluginName}`,
+		});
+	} else if (isThemeDirectory(path)) {
+		const themeName = basename(path);
+		mount.push({
+			hostPath: path,
+			vfsPath: `/wordpress/wp-content/themes/${themeName}`,
+		});
+	} else if (containsWpContentDirectories(path)) {
+		mount.push(...wpContentMounts(path));
+	} else if (containsFullWordPressInstallation(path)) {
+		/**
+		 * We don't want Playground and WordPress to modify the OS filesystem on their own
+		 * by creating files like wp-config.php or wp-content/db.php.
+		 * To ensure WordPress can write to the /wordpress/ and /wordpress/wp-content/ directories,
+		 * we leave these directories as MEMFS nodes and mount individual files
+		 * and directories into them instead of mounting the entire directory as a NODEFS node.
+		 */
+		const files = fs.readdirSync(path);
+		const mounts: Mount[] = [];
+		for (const file of files) {
+			if (file.startsWith('wp-content')) {
+				continue;
+			}
+			mounts.push({
+				hostPath: `${path}/${file}`,
+				vfsPath: `/wordpress/${file}`,
+			});
+		}
+		mountBeforeInstall.push(
+			...mounts,
+			...wpContentMounts(join(path, 'wp-content'))
+		);
+	} else {
+		/**
+		 * By default, mount the current working directory as the Playground root.
+		 * This allows users to run and PHP or HTML files using the Playground CLI.
+		 */
+		mount.push({ hostPath: path, vfsPath: '/wordpress' });
+	}
+
+	const blueprint = (args.blueprint as BlueprintDeclaration) || {};
+	blueprint.steps = [...(blueprint.steps || []), ...getSteps(path)];
+
+	/**
+	 * If Playground is mounting a full WordPress directory,
+	 * it doesn't need to setup WordPress.
+	 */
+	const skipWordPressSetup =
+		args.skipWordPressSetup || containsFullWordPressInstallation(path);
+
+	return {
+		...args,
+		blueprint,
+		mount,
+		mountBeforeInstall,
+		skipWordPressSetup,
+	} as RunCLIArgs;
+}
+
+export function containsFullWordPressInstallation(path: string): boolean {
+	const files = fs.readdirSync(path);
+	return (
+		files.includes('wp-admin') &&
+		files.includes('wp-includes') &&
+		files.includes('wp-content')
+	);
+}
+
+export function containsWpContentDirectories(path: string): boolean {
+	const files = fs.readdirSync(path);
+	return (
+		files.includes('themes') ||
+		files.includes('plugins') ||
+		files.includes('mu-plugins') ||
+		files.includes('uploads')
+	);
+}
+
+export function isThemeDirectory(path: string): boolean {
+	const files = fs.readdirSync(path);
+	if (!files.includes('style.css')) {
+		return false;
+	}
+	const styleCssContent = fs.readFileSync(join(path, 'style.css'), 'utf8');
+	const themeNameRegex = /^(?:[ \t]*<\?php)?[ \t/*#@]*Theme Name:(.*)$/im;
+	return !!themeNameRegex.exec(styleCssContent);
+}
+
+export function isPluginDirectory(path: string): boolean {
+	const files = fs.readdirSync(path);
+	const pluginNameRegex = /^(?:[ \t]*<\?php)?[ \t/*#@]*Plugin Name:(.*)$/im;
+	const pluginNameMatch = files
+		.filter((file) => file.endsWith('.php'))
+		.find((file) => {
+			const fileContent = fs.readFileSync(join(path, file), 'utf8');
+			return !!pluginNameRegex.exec(fileContent);
+		});
+	return !!pluginNameMatch;
+}
+
+/**
+ * Returns a list of files and directories in the wp-content directory
+ * to be mounted individually.
+ *
+ * This is needed because WordPress needs to be able to write to the
+ * wp-content directory without Playground modifying the OS filesystem.
+ *
+ * See expandAutoMounts for more details.
+ */
+export function wpContentMounts(wpContentDir: string): Mount[] {
+	const files = fs.readdirSync(wpContentDir);
+	return (
+		files
+			/**
+			 * index.php is added by WordPress automatically and
+			 * can't be mounted from the current working directory
+			 * because it already exists.
+			 *
+			 * Because index.php should be empty, it's safe to not include it.
+			 */
+			.filter((file) => !file.startsWith('index.php'))
+			.map((file) => ({
+				hostPath: `${wpContentDir}/${file}`,
+				vfsPath: `/wordpress/wp-content/${file}`,
+			}))
+	);
+}
+
+export function getSteps(path: string): StepDefinition[] {
+	if (isPluginDirectory(path)) {
+		return [
+			{
+				step: 'activatePlugin',
+				pluginPath: `/wordpress/wp-content/plugins/${basename(path)}`,
+			},
+		];
+	} else if (isThemeDirectory(path)) {
+		return [
+			{
+				step: 'activateTheme',
+				themeFolderName: basename(path),
+			},
+		];
+	} else if (
+		containsWpContentDirectories(path) ||
+		containsFullWordPressInstallation(path)
+	) {
+		/**
+		 * Playground needs to ensure there is an active theme.
+		 * Otherwise when WordPress loads it will show a white screen.
+		 */
+		return [
+			{
+				step: 'runPHP',
+				code: `<?php
+					require_once '/wordpress/wp-load.php';
+					$theme = wp_get_theme();
+					if (!$theme->exists()) {
+						$themes = wp_get_themes();
+						if (count($themes) > 0) {
+							$themeName = array_keys($themes)[0];
+							switch_theme($themeName);
+						}
+					}
+				`,
+			},
+		];
+	}
+	return [];
+}

packages/playground/cli/src/mount.ts

@@ -63,7 +63,7 @@ export async function resolveBlueprint({
 	switch (extension) {
 		case '.zip':
 			return ZipFilesystem.fromArrayBuffer(
-				fs.readFileSync(blueprintPath)
+				fs.readFileSync(blueprintPath).buffer as ArrayBuffer
 			);
 		case '.json': {
 			const blueprintText = fs.readFileSync(blueprintPath, 'utf-8');