Build Optimizations

/**
 * Vue I18n build selection strategy
 */
interface BuildSelection {
  /**
   * Development builds include full message compiler
   * Production builds use runtime-only for smaller size
   */
  development: 'vue-i18n.esm-bundler.js';
  production: 'vue-i18n.runtime.esm-bundler.js';
  
  /**
   * Alternative module support
   */
  petite: {
    development: 'petite-vue-i18n.esm-bundler.js';
    production: 'petite-vue-i18n.runtime.esm-bundler.js';
  };
}

/**
 * Runtime-only build configuration
 */
interface RuntimeOnlyOptions {
  /**
   * Use Vue I18n runtime-only build in production
   * Excludes message compiler from final bundle
   * @default true
   */
  runtimeOnly?: boolean;
}

VueI18nPlugin({
  runtimeOnly: true  // Automatic in production, full build in development
});

// Results in bundler alias configuration:
// Production: vue-i18n → vue-i18n.runtime.esm-bundler.js
// Development: vue-i18n → vue-i18n.esm-bundler.js

/**
 * Composition API optimization
 */
interface CompositionAPIOptions {
  /**
   * Tree-shake legacy Options API, use Composition API only
   * Removes $t, $tc, $te methods from Vue instances
   * @default true
   */
  compositionOnly?: boolean;
}

// With compositionOnly: true (default)
// ✅ Available: useI18n(), useScope(), etc.
// ❌ Removed: this.$t, this.$tc, this.$te, etc.

// With compositionOnly: false  
// ✅ Available: Both Composition and Options API
// ⚠️ Larger bundle size

/**
 * Full install feature control
 */
interface FullInstallOptions {
  /**
   * Install full Vue I18n feature set including built-in components
   * When false, excludes i18n-t, i18n-n, i18n-d components and v-t directive
   * @default true
   */
  fullInstall?: boolean;
}

// With fullInstall: true (default)
// ✅ Available: <i18n-t>, <i18n-n>, <i18n-d> components
// ✅ Available: v-t directive
// ✅ Available: All utility functions

// With fullInstall: false
// ❌ Components and directive tree-shaken
// ✅ Available: Core i18n functions only
// ⚠️ Smaller bundle size

/**
 * Message compiler optimization
 */
interface MessageCompilerOptions {
  /**
   * Tree-shake message compiler from bundle
   * Requires pre-compiled messages (no runtime compilation)
   * @default false
   */
  dropMessageCompiler?: boolean;
}

VueI18nPlugin({
  dropMessageCompiler: true,
  // Must pre-compile all messages
  include: ['./locales/**']
});

// ⚠️ Warning: All messages must be pre-compiled
// ❌ Runtime message compilation will fail
// ✅ Significant bundle size reduction

/**
 * SSR build configuration
 */
interface SSROptions {
  /**
   * Enable SSR-specific Vue I18n bundle
   * Includes server-side optimizations
   * @default false
   */
  ssr?: boolean;
}

// For SSR applications
VueI18nPlugin({
  ssr: true,
  optimizeTranslationDirective: true  // Required for v-t directive in SSR
});

/**
 * Translation directive optimization
 */
interface DirectiveOptimizationOptions {
  /**
   * Optimize v-t directive transformation
   * Converts v-t to function calls at compile time
   * Required for SSR applications using v-t
   * @default false
   */
  optimizeTranslationDirective?: boolean | string | string[];
}

// Basic optimization
VueI18nPlugin({
  optimizeTranslationDirective: true
});

// Custom translation function signatures
VueI18nPlugin({
  optimizeTranslationDirective: ['$t', 'translate', 'getMessage']
});

<!-- Before optimization -->
<p v-t="'message.key'"></p>
<span v-t="{ path: 'user.name', args: { name: 'John' } }"></span>

<!-- After optimization (compile-time transformation) -->
<p>{{ $t('message.key') }}</p>
<span>{{ $t('user.name', { name: 'John' }) }}</span>

/**
 * Module type selection
 */
interface ModuleTypeOptions {
  /**
   * Target Vue I18n module variant
   * @default 'vue-i18n'
   */
  module?: VueI18nModule;
}

type VueI18nModule = 'vue-i18n' | 'petite-vue-i18n';

// vue-i18n (default) - Full-featured
VueI18nPlugin({
  module: 'vue-i18n'
  // ✅ All features available
  // ✅ Complete API surface
  // ⚠️ Larger bundle size
});

// petite-vue-i18n - Lightweight
VueI18nPlugin({
  module: 'petite-vue-i18n'
  // ✅ Core i18n functionality
  // ❌ Reduced feature set
  // ✅ Smaller bundle size
});

/**
 * String formatting optimization
 */
interface StringFormattingOptions {
  /**
   * Force stringify numbers, booleans, and null values
   * Converts them to message functions returning strings
   * @default false
   */
  forceStringify?: boolean;
}

// Original locale data
{
  "count": 42,
  "enabled": true,
  "value": null
}

// With forceStringify: false (default)
const messages = {
  count: 42,           // number
  enabled: true,       // boolean  
  value: null         // null
};

// With forceStringify: true
const messages = {
  count: () => "42",      // function returning string
  enabled: () => "true",  // function returning string
  value: () => "null"     // function returning string
};

/**
 * Typical bundle size impact of optimizations
 */
interface BundleSizeImpact {
  baseline: '~100KB';           // Full Vue I18n with all features
  runtimeOnly: '~75KB';         // -25% (no message compiler)
  compositionOnly: '~85KB';     // -15% (no Options API)
  fullInstall_false: '~80KB';   // -20% (no built-in components)
  dropMessageCompiler: '~60KB'; // -40% (requires pre-compilation)
  petiteVueI18n: '~40KB';       // -60% (lightweight variant)
  
  // Combined optimizations
  aggressive: '~30KB';          // All optimizations enabled
}

/**
 * Runtime performance optimizations
 */
interface PerformanceOptimizations {
  preCompiledMessages: {
    impact: 'Significant';
    description: 'Messages compiled to functions at build time';
    benefit: 'No runtime parsing or compilation overhead';
  };
  
  treeShaking: {
    impact: 'Moderate';
    description: 'Unused APIs removed from bundle';
    benefit: 'Faster JavaScript parsing and execution';
  };
  
  directiveOptimization: {
    impact: 'Moderate';
    description: 'v-t directive compiled to function calls';
    benefit: 'Reduced runtime directive processing';
  };
}

// Maximum optimization for production
VueI18nPlugin({
  // Build optimizations
  runtimeOnly: true,
  compositionOnly: true,
  fullInstall: false,
  dropMessageCompiler: true,
  
  // Performance optimizations
  forceStringify: true,
  optimizeTranslationDirective: true,
  
  // Resource optimization
  include: ['./locales/**'],
  onlyLocales: ['en', 'fr', 'de'],
  
  // Security
  strictMessage: true,
  escapeHtml: true
});

// Development configuration with debugging support
VueI18nPlugin({
  // Keep full builds for development
  runtimeOnly: false,
  compositionOnly: false,
  fullInstall: true,
  dropMessageCompiler: false,
  
  // Flexible during development
  strictMessage: false,
  allowDynamic: true,
  
  // Resource processing
  include: ['./locales/**', './src/**/*.vue'],
  defaultSFCLang: 'yaml'  // More readable in development
});

// Server-side rendering optimization
VueI18nPlugin({
  // SSR requirements
  ssr: true,
  optimizeTranslationDirective: true,  // Required for v-t in SSR
  
  // Production optimizations
  runtimeOnly: true,
  compositionOnly: true,
  dropMessageCompiler: true,
  
  // Resource handling
  include: ['./locales/**'],
  globalSFCScope: false  // Better for SSR hydration
});

// Optimized for micro-frontend architecture
VueI18nPlugin({
  // Minimal footprint
  module: 'petite-vue-i18n',
  fullInstall: false,
  compositionOnly: true,
  dropMessageCompiler: true,
  
  // Shared resources only
  onlyLocales: ['en'],
  include: ['./shared-locales/**'],
  
  // No global scope to avoid conflicts
  globalSFCScope: false
});