Add CLI tool with stats, missing keys, and unused keys detection commands

.rspec

@@ -1 +1,2 @@
 --require spec_helper
+--color

README.md

@@ -359,6 +359,27 @@ date = Date.new(2023, 8, 15)
 => ["1,000 $", "1.000 €", "1.000 €"]
 ```
 
+## CLI Tool
+
+`MiniI18n` includes a CLI tool for managing translations. It provides commands to analyze translation coverage and find unused translation keys in your codebase.
+
+```
+Usage: mi18n [command] [options]
+
+Commands:
+  stats                    Show translation statistics
+  missing [--locale=LOCALE] Show missing translation keys
+  unused [--paths=PATHS]   Show unused translation keys
+  version                  Show version
+  help                     Show this help message
+
+Examples:
+  mi18n stats
+  mi18n missing --locale=es
+  mi18n unused                           # Scan default paths for unused keys
+  mi18n unused --paths="app/**/*.rb"     # Scan custom paths for unused keys
+```
+
 ## Development
 
 Feedback, bug reports, ideas, and enhancements are welcome!

bin/mi18n

@@ -0,0 +1,7 @@
+#!/usr/bin/env ruby
+
+$LOAD_PATH.unshift File.expand_path('../lib', __dir__)
+
+require 'mini_i18n/cli'
+
+MiniI18n::CLI.new(ARGV).run

lib/mini_i18n/cli.rb

@@ -0,0 +1,264 @@
+require 'mini_i18n'
+require 'optparse'
+require 'set'
+require 'yaml'
+
+module MiniI18n
+  class CLI
+    def initialize(args = [])
+      @args = args
+      @options = {}
+    end
+
+    def run
+      case @args.first
+      when 'stats'
+        stats_command
+      when 'missing'
+        missing_command
+      when 'unused'
+        unused_command
+      when 'version'
+        version_command
+      when 'help', nil
+        help_command
+      else
+        puts "Unknown command: #{@args.first}"
+        puts "Run 'mi18n help' for available commands"
+        exit 1
+      end
+    end
+
+    private
+
+    def stats_command
+      load_translations_for_cli
+
+      locales = MiniI18n.available_locales
+      total_keys = collect_all_keys
+
+      puts "Translation Statistics:"
+      puts "====================="
+      puts "Number of locales: #{locales.count}"
+      puts "Total unique keys: #{total_keys.count}"
+      puts ""
+
+      locales.each do |locale|
+        translated_keys = count_translated_keys(locale, total_keys)
+        completion = (translated_keys.to_f / total_keys.count * 100).round(1)
+        puts "#{locale}: #{translated_keys}/#{total_keys.count} keys (#{completion}% complete)"
+      end
+    end
+
+    def missing_command
+      options = parse_missing_options
+      load_translations_for_cli
+
+      total_keys = collect_all_keys
+      locales = options[:locale] ? [options[:locale]] : MiniI18n.available_locales
+
+      locales.each do |locale|
+        missing_keys = find_missing_keys(locale, total_keys)
+
+        if missing_keys.any?
+          puts "Missing keys for '#{locale}' locale:"
+          missing_keys.each { |key| puts "  #{key}" }
+          puts ""
+        elsif locales.count == 1
+          puts "No missing keys for '#{locale}' locale"
+        end
+      end
+    end
+
+    def unused_command
+      options = parse_unused_options
+      load_translations_for_cli
+
+      # Find all translation keys
+      all_translation_keys = collect_all_keys.to_set
+
+      # Find used keys in source files
+      used_keys = find_used_translation_keys(options[:paths])
+
+      # Find unused keys
+      unused_keys = (all_translation_keys - used_keys).to_a.sort
+
+      if unused_keys.any?
+        puts "Unused translation keys:"
+        puts "======================"
+        unused_keys.each { |key| puts "  #{key}" }
+        puts ""
+        puts "Total unused keys: #{unused_keys.count}"
+      else
+        puts "No unused translation keys found"
+      end
+    end
+
+    def version_command
+      puts MiniI18n::VERSION
+    end
+
+    def help_command
+      puts <<~HELP
+        Usage: mi18n [command] [options]
+
+        Commands:
+          stats                    Show translation statistics
+          missing [--locale=LOCALE] Show missing translation keys
+          unused [--paths=PATHS]   Show unused translation keys
+          version                  Show version
+          help                     Show this help message
+
+        Examples:
+          mi18n stats
+          mi18n missing --locale=es
+          mi18n unused                           # Scan default paths for unused keys
+          mi18n unused --paths="app/**/*.rb"     # Scan custom paths for unused keys
+      HELP
+    end
+
+    def parse_missing_options
+      options = {}
+      OptionParser.new do |opts|
+        opts.on('--locale=LOCALE', 'Filter by specific locale') do |locale|
+          options[:locale] = locale
+        end
+      end.parse!(@args[1..-1])
+      options
+    end
+
+    def parse_unused_options
+      options = { paths: nil }
+      OptionParser.new do |opts|
+        opts.on('--paths=PATHS', 'Comma-separated glob patterns to scan (default: ./**/*.{rb,erb})') do |paths|
+          options[:paths] = paths.split(',').map(&:strip)
+        end
+      end.parse!(@args[1..-1])
+
+      # Set default paths if none provided
+      options[:paths] ||= [
+        './**/*.{rb,erb}'
+      ]
+
+      options
+    end
+
+    def load_translations_for_cli
+      # Check if translations are already loaded
+      return unless MiniI18n.translations.empty?
+
+      # Try to load translations from common locations
+      possible_paths = [
+        'config/locales/*.yml',
+        'config/locales/*.yaml',
+        'locales/*.yml',
+        'locales/*.yaml',
+        'translations/*.yml',
+        'translations/*.yaml'
+      ]
+
+      loaded = false
+      possible_paths.each do |pattern|
+        files = Dir.glob(pattern)
+        if files.any?
+          MiniI18n.load_translations(pattern)
+          loaded = true
+          break
+        end
+      end
+
+      unless loaded
+        puts "Warning: No translation files found in common locations:"
+        puts "  config/locales/*.yml"
+        puts "  locales/*.yml"
+        puts "  translations/*.yml"
+        puts ""
+      end
+    end
+
+    def collect_all_keys
+      all_keys = Set.new
+
+      MiniI18n.translations.each do |locale, translations|
+        collect_keys_recursive(translations).each { |key| all_keys << key }
+      end
+
+      all_keys.to_a.sort
+    end
+
+    def collect_keys_recursive(hash, prefix = "")
+      keys = []
+      hash.each do |key, value|
+        full_key = prefix.empty? ? key.to_s : "#{prefix}.#{key}"
+
+        if value.is_a?(Hash)
+          keys.concat(collect_keys_recursive(value, full_key))
+        else
+          keys << full_key
+        end
+      end
+      keys
+    end
+
+    def count_translated_keys(locale, all_keys)
+      all_keys.count do |key|
+        value = MiniI18n.t(key, locale: locale, default: nil)
+        !value.nil? && !value.to_s.strip.empty?
+      end
+    end
+
+    def find_missing_keys(locale, all_keys)
+      all_keys.select do |key|
+        value = MiniI18n.t(key, locale: locale, default: nil)
+        value.nil? || value.to_s.strip.empty?
+      end
+    end
+
+
+    def find_used_translation_keys(paths)
+      used_keys = Set.new
+
+      paths.each do |pattern|
+        Dir.glob(pattern).each do |file_path|
+          next unless File.file?(file_path)
+
+          begin
+            content = File.read(file_path)
+
+            # Find translation method calls with various patterns
+            # T(:key), T('key'), T("key")
+            content.scan(/\bT\s*\(\s*:([a-zA-Z_][a-zA-Z0-9_.]*)\s*\)/) do |match|
+              used_keys << match[0]
+            end
+
+            content.scan(/\bT\s*\(\s*['"]([^'"]+)['"]\s*\)/) do |match|
+              used_keys << match[0]
+            end
+
+            # MiniI18n.t(:key), MiniI18n.t('key'), MiniI18n.translate(:key)
+            content.scan(/\bMiniI18n\.(?:t|translate)\s*\(\s*:([a-zA-Z_][a-zA-Z0-9_.]*)\s*\)/) do |match|
+              used_keys << match[0]
+            end
+
+            content.scan(/\bMiniI18n\.(?:t|translate)\s*\(\s*['"]([^'"]+)['"]\s*\)/) do |match|
+              used_keys << match[0]
+            end
+
+            # Handle scoped calls like T('key', scope: 'scope')
+            content.scan(/\bT\s*\(\s*['"]([^'"]+)['"]\s*,\s*scope:\s*['"]([^'"]+)['"]/) do |key, scope|
+              used_keys << "#{scope}.#{key}"
+            end
+
+          rescue => e
+            # Skip files that can't be read (binary files, etc.)
+            next
+          end
+        end
+      end
+
+      used_keys
+    end
+
+
+  end
+end

mini_i18n.gemspec

@@ -12,6 +12,7 @@ Gem::Specification.new do |spec|
   spec.files         = Dir.glob("lib/**/*")
   spec.test_files    = Dir.glob("spec/**/*")
   spec.require_paths = ["lib"]
+  spec.executables   = ["mi18n"]
 
   spec.required_ruby_version = ">= 2.3"