require 'sinatra'
require 'json'
require 'yaml'

# Configure Sinatra
set :port, ENV['PORT'] || 4567
set :bind, '0.0.0.0'
set :public_folder, 'public'
set :views, 'views'

# Load responses from YAML file
RESPONSES = YAML.load_file('responses.yml')
DEFAULT_LANGUAGE = 'en'

# Helper method to get a random "no" response
def get_no_response(lang = DEFAULT_LANGUAGE)
  language = RESPONSES[lang] || RESPONSES[DEFAULT_LANGUAGE]
  language['responses'].sample
end

# Helper method to get language name
def get_language_name(lang)
  language = RESPONSES[lang] || RESPONSES[DEFAULT_LANGUAGE]
  language['name']
end

# Helper method to get available languages
def get_available_languages
  RESPONSES.map { |code, data| { code: code, name: data['name'] } }
end

# Helper method to determine language from request
def determine_language(params, headers)
  # Priority: URL parameter > Accept-Language header > default
  return params[:lang] if params[:lang] && RESPONSES[params[:lang]]

  # Parse Accept-Language header
  if headers['HTTP_ACCEPT_LANGUAGE']
    accepted_langs = headers['HTTP_ACCEPT_LANGUAGE']
                      .split(',')
                      .map { |lang| lang.split(';').first.downcase.strip }

    # Check for exact matches first
    accepted_langs.each do |lang|
      return lang if RESPONSES[lang]
    end

    # Check for language family matches (e.g., 'nb' or 'nn' -> 'no')
    accepted_langs.each do |lang|
      case lang
      when /^zh/ # Chinese variants
        return 'zh'
      when /^es/ # Spanish variants
        return 'es'
      when /^hi/ # Hindi variants
        return 'hi'
      when /^ar/ # Arabic variants
        return 'ar'
      when /^bn/ # Bengali variants
        return 'bn'
      when /^pt/ # Portuguese variants
        return 'pt'
      when /^ru/ # Russian variants
        return 'ru'
      when /^ja/ # Japanese variants
        return 'ja'
      when /^tr/ # Turkish variants
        return 'tr'
      when /^ko/ # Korean variants
        return 'ko'
      when /^fr/ # French variants
        return 'fr'
      when /^de/ # German variants
        return 'de'
      when /^vi/ # Vietnamese variants
        return 'vi'
      when /^it/ # Italian variants
        return 'it'
      when /^th/ # Thai variants
        return 'th'
      when /^pl/ # Polish variants
        return 'pl'
      when /^nl/ # Dutch variants
        return 'nl'
      when /^ur/ # Urdu variants
        return 'ur'
      when /^ms/ # Malay variants
        return 'ms'
      when /^nb|nn/ # Norwegian Bokmål/Nynorsk
        return 'no'
      when /^sv/ # Swedish variants
        return 'sv'
      when /^da/ # Danish variants
        return 'da'
      when /^is/ # Icelandic variants
        return 'is'
      when /^fi/ # Finnish variants
        return 'fi'
      when /^fo/ # Faroese variants
        return 'fo'
      when /^se|smi/ # Sami variants
        return 'smi'
      end
    end
  end

  DEFAULT_LANGUAGE
end

# Root endpoint - returns HTML by default
get '/' do
  lang = determine_language(params, request.env)
  no_response = get_no_response(lang)

  case request.accept.first&.to_s
  when /application\/json/
    content_type :json
    {
      answer: no_response,
      language: lang,
      language_name: get_language_name(lang),
      timestamp: Time.now.iso8601
    }.to_json
  else
    content_type :html
    erb :index, locals: {
      no_response: no_response,
      language: lang,
      language_name: get_language_name(lang),
      available_languages: get_available_languages
    }
  end
end

# Languages endpoint - list available languages
get '/languages' do
  content_type :json
  {
    languages: get_available_languages,
    default: DEFAULT_LANGUAGE,
    timestamp: Time.now.iso8601
  }.to_json
end

# Explicit JSON endpoint with language support
get '/api/no' do
  lang = determine_language(params, request.env)

  content_type :json
  {
    answer: get_no_response(lang),
    language: lang,
    language_name: get_language_name(lang),
    timestamp: Time.now.iso8601,
    service: "No as a Service",
    version: "2.0.0"
  }.to_json
end

# Language-specific endpoint
get '/api/no/:lang' do
  lang = params[:lang]

  unless RESPONSES[lang]
    content_type :json
    status 404
    return {
      error: "Language not supported",
      requested: lang,
      available: get_available_languages.map { |l| l[:code] },
      timestamp: Time.now.iso8601
    }.to_json
  end

  content_type :json
  {
    answer: get_no_response(lang),
    language: lang,
    language_name: get_language_name(lang),
    timestamp: Time.now.iso8601,
    service: "No as a Service",
    version: "2.0.0"
  }.to_json
end

# Health check endpoint
get '/health' do
  content_type :json
  {
    status: "healthy",
    languages_loaded: RESPONSES.keys.size,
    timestamp: Time.now.iso8601
  }.to_json
end

# Catch-all route for any other endpoint
get '/*' do
  lang = determine_language(params, request.env)
  no_response = get_no_response(lang)

  case request.accept.first&.to_s
  when /application\/json/
    content_type :json
    {
      answer: no_response,
      language: lang,
      language_name: get_language_name(lang),
      timestamp: Time.now.iso8601
    }.to_json
  else
    content_type :html
    erb :index, locals: {
      no_response: no_response,
      language: lang,
      language_name: get_language_name(lang),
      available_languages: get_available_languages
    }
  end
end