require 'rack'

module Voom
  module Presenters
    module Api
      class Router

        attr_reader :base_url

        def initialize(base_url: nil)
          @base_url = base_url
        end

        def url(command: nil, render: nil, entity: nil, context:)
          _params_ = context.dup
          # if it is a local page command
          # return build_local_render(command, render, entity, _params_) if local_render?(render)
          return build_render_url(render, entity, _params_) unless command
          _params_[:redirect]=build_render_url(render, entity, _params_) if render
          build_command_url(command, entity, _params_)
        end

        def local_render?(render)
          return unless render
          render.to_s.start_with?('#')
        end

        def build_local_render(command, render, entity, context)

          client_command = render[/(.*?)\(/m, 1]

          start_params = render.index('(')
          end_params = render.rindex(')')
          client_params = render[start_params+1..end_params-1]
          client_params = client_params.split(',')

          client_command += '('
          client_params.each.with_index do |p, index|
            client_command += ',' if index > 0
            url_var = p[/{url\((.*?)\)}/m, 1]
            client_command += build_client_url(url_var.strip, entity, context) if url_var && command.nil?
            client_command += p.strip unless url_var
          end
          client_command += ')'
        end

        def join_errors
          '<br/>'
        end

        def scrub_params(_params_)
          # _params_.delete('captures')
          # _params_.delete('render')
          # _params_.delete('view')
          _params_.delete('presenter')
          # _params_.delete('redirect')
          _params_.delete('action')
          _params_.delete('errors')
          _params_
        end

        private

        def build_command_url(command, entity, params)
          return '' unless command
          "#{command}?#{build_params(params, entity)}"
        end

        def build_render_url(render_, entity, params)
          return '#' unless render_
          render = render_.to_s
          seperator = render.start_with?('/') ? '' : '/'
          url = "#{base_url}#{seperator}#{render}"
          query_params = build_params(params, entity)
          if(query_params)
            query_seperator = render.include?('?') ? '&' : '?'
            url = "#{url}#{query_seperator}#{query_params}"
          end
          url
        end

        def build_client_url(render, entity, params)
          return '#' unless render
          "#{base_url}/web/#{render}?layout=false&#{build_params(params, entity)}"
        end

        def build_params(params, entity)
          params = params.merge(entity_key: entity.id) if entity
          Rack::Utils.build_nested_query(scrub_params(params))
        end
      end
    end
  end
end