generate-vue-i18n.js

#!/usr/bin/env node

/**
 * Script to automatically generate vue-i18n.d.ts TypeScript definitions
 * based on the structure of src/locales/en.json.
 */

import fs from "fs"
import path from "path"
import { fileURLToPath } from "url"

// Get current directory for ES modules.
const __filename = fileURLToPath(import.meta.url)
const __dirname = path.dirname(__filename)

// File paths.
const EN_JSON_PATH = path.join(__dirname, "src", "locales", "en.json")
const VUE_I18N_DEFS_PATH = path.join(__dirname, "src", "vue-i18n.d.ts")

/**
 * Convert a JSON object structure to TypeScript interface properties.
 * @param {any} obj - The JSON object to convert.
 * @param {number} indent - Current indentation level.
 * @returns {string} TypeScript interface properties.
 */
function jsonToTypeScript(obj, indent = 0) {
  const indentStr = "  ".repeat(indent)

  if (typeof obj === "string") {
    return "string"
  }

  if (Array.isArray(obj)) {
    // Handle arrays (shouldn't occur in locale files, but just in case).
    return "string[]"
  }

  if (typeof obj === "object" && obj !== null) {
    const entries = Object.entries(obj)
    const properties = entries.map(([key, value]) => {
      if (/^\d/.test(key)) {
        key = '"' + key + '"'
      }
      if (typeof value === "object" && value !== null && !Array.isArray(value)) {
        // Nested object.
        const nestedContent = jsonToTypeScript(value, indent + 1)
        return `${indentStr}${key}: {\n${nestedContent}\n${indentStr}}`
      } else {
        // Simple property.
        return `${indentStr}${key}: string`
      }
    })

    return properties.join("\n")
  }

  return "string"
}

/**
 * Generate the complete vue-i18n.d.ts file content.
 * @param {Object} localeData - The parsed locale JSON data.
 * @returns {string} Complete TypeScript definition file content.
 */
function generateTypeScriptDefinitions(localeData) {
  const interfaceContent = jsonToTypeScript(localeData, 2) // Start with 2-level indentation for proper formatting.

  return `/**
 * AUTOMATICALLY GENERATED FILE - DO NOT EDIT MANUALLY
 *
 * This file is auto-generated by generate-vue-i18n.js script based on src/locales/en.json.
 * To update this file, modify src/locales/en.json and run: npm run generate-vue-i18n.
 */

// This empty export makes TypeScript treat this file as a module.
export {}

declare module "vue-i18n" {
  export interface DefineLocaleMessage {
${interfaceContent}
  }
}
`
}

/**
 * Main function to read en.json and generate vue-i18n.d.ts.
 */
function main() {
  try {
    console.log("🔍 Reading en.json file...")

    // Check if en.json exists.
    if (!fs.existsSync(EN_JSON_PATH)) {
      console.error(`❌ Error: ${EN_JSON_PATH} not found!`)
      process.exit(1)
    }

    // Read and parse en.json.
    const rawData = fs.readFileSync(EN_JSON_PATH, "utf8")
    const localeData = JSON.parse(rawData)

    console.log("✅ Successfully parsed en.json")
    console.log("🛠️  Generating TypeScript definitions...")

    // Generate TypeScript definitions.
    const typeScriptContent = generateTypeScriptDefinitions(localeData)

    // Write to vue-i18n.d.ts.
    fs.writeFileSync(VUE_I18N_DEFS_PATH, typeScriptContent, "utf8")

    console.log("✅ Successfully generated vue-i18n.d.ts")
    console.log(`📁 Written to: ${VUE_I18N_DEFS_PATH}`)

    // Validate the generated file.
    if (fs.existsSync(VUE_I18N_DEFS_PATH)) {
      const generatedSize = fs.statSync(VUE_I18N_DEFS_PATH).size
      console.log(`📊 Generated file size: ${generatedSize} bytes`)
      console.log("🎉 Generation completed successfully!")
    }
  } catch (error) {
    console.error("❌ Error generating vue-i18n.d.ts:", error.message)
    process.exit(1)
  }
}

// Run the script if executed directly.
main()

export { generateTypeScriptDefinitions, jsonToTypeScript, main }