module SvelteOnRails
  module Installer
    module Npm

      def self.install_or_update_package(package_name, minimal_version: nil, major_version: nil, update_to_latest: true, dev_dependency: false)
        pkg = inspect_package(package_name)
        puts "#{package_name} already installed (#{pkg[:version].join('.')})" if pkg

        to_do = if !pkg
                  true
                elsif major_version
                  r = pkg[:version].first != major_version
                  if r
                    puts "updating to major version #{major_version}"
                  else
                    puts "nothing to do (major version #{major_version} OK)"
                  end
                  r
                elsif minimal_version
                  r = pkg[:version].first < minimal_version.first || pkg[:version].second < minimal_version.second
                  puts "updating to minimal version #{minimal_version}" if r
                  r
                else
                  puts 'nothing to do'
                  false
                end

        save_dev = (dev_dependency ? ' --save-dev' : '')
        if to_do

          cmd = if major_version
                  "npm install #{package_name}@#{major_version}#{save_dev}"
                elsif update_to_latest
                  "npm install #{package_name}@latest#{save_dev}"
                else
                  raise "ERROR: not implemented"
                end

          stdout, stderr, status = Open3.capture3(cmd)

          puts cmd

          if stderr.present?
            raise "ERROR #{cmd} => #{stderr}"
          end

          notice = [
            (pkg ? "Updated" : "Installed"),
            package_name,
            (pkg ? "from version #{pkg[:version].join('.')}" : nil),
            (pkg ? "to" : nil),
            "@latest"
          ].compact.join(' ')

          puts notice

        else
          min_str = minimal_version.present? ? ", required: >= #{minimal_version.join('.')}" : ''
          puts "#{package_name} already installed (#{pkg[:version].join('.')}#{min_str}), skipping."
        end
      end

      def self.link_local_package(package_name, local_package_url)
        Dir.chdir(local_package_url) do
          `npm unlink`
          `npm link`
        end
        Dir.chdir(Rails.root) do
          # Instead of just `npm link`, use `npm install` to add the local package to package.json
          `npm install #{local_package_url} --save`
          stdout, stderr, status = Open3.capture3("npm ls #{package_name}")
          if stderr.present?
            raise "ERROR: npm link failed for #{package_name} => #{stderr}"
          end
          puts "Successfully linked #{package_name} to #{local_package_url}"
          puts "  • `npm ls #{package_name}` => «#{stdout}»"
        end
      end

      def self.inspect_package(package_name)
        pkg = nil
        version = nil

        if File.exist?('package-lock.json')
          pl = JSON.parse(File.read('package-lock.json'))
          unless pl['packages']
            raise "ERROR: package-lock.json found, but no packages found, seems to be corrupted."
          end
          pkg = pl['packages'].keys.grep(/\/#{package_name}$/).first
          version = pl['packages'][pkg]['version'] if pkg
        end

        if pkg
          {
            type: pkg.match(/^.*?(?=\/[^\/]*$)/).to_s,
            version: version&.split('.')&.map(&:to_i)
          }
        end

      end

      # def self.check_version(current_version, minimal_version)
      #   if !current_version
      #     return false
      #   elsif !minimal_version.present?
      #     return true
      #   else
      #     compare_version_arrays(current_version, minimal_version)
      #   end
      # end

      private

      # def self.compare_version_arrays(current_version, minimal_version)
      #   raise "ERROR: current_version must be an array" unless current_version.is_a?(Array)
      #
      #   current_version.each_with_index do |v, i|
      #     raise "ERROR: current_version entries must be an integer" unless v.is_a?(Integer)
      #
      #     if minimal_version[i]
      #       raise "ERROR: minimal_version entries must be an integer" unless minimal_version[i].is_a?(Integer)
      #       if v < minimal_version[i]
      #         return false
      #       end
      #     end
      #   end
      #   true
      # end

    end
  end
end