# frozen_string_literal: true

module QuestionsCrafter
  module Ui
    class CssClassesManager
      # Class structure template with default semantic/structural classes
      CLASS_STRUCTURE = {
        required_fields_notice: {
          container: "",
          text: ""
        },
        page: {
          main: "questions-page",
          title: "questions-title",
          description: "questions-description"
        },
        form: {
          wrapper: "questions-form-wrapper",
          main: "questions-form",
          fields_wrapper: "questions-form-fields-wrapper",
          submit_wrapper: "questions-form-submit-wrapper",
          back_link_wrapper: ""
        },
        submit_button: "",
        back_link: "",
        question: {
          wrapper: "question-field-wrapper",
          label: "question-field-label",
          required_notice: "question-required-notice",
          description: "question-field-description",
          error: "question-field-error"
        },
        input_fields: {
          text_input: "question-string-field",
          textarea: "question-textarea",
          number_input: "question-number-field",
          select: "question-select-field"
        },
        radio_group: {
          container: "question-radio-group",
          item_wrapper: "question-radio-group-item-wrapper",
          item_wrapper_inline: "question-radio-group-item-wrapper-inline",
          input: "question-radio-group-input",
          label: "question-radio-group-label"
        },
        checkbox: {
          wrapper: "question-checkbox-wrapper",
          input: "question-checkbox-input",
          label: "question-checkbox-label"
        },
        checkbox_group: {
          container: "question-checkbox-group",
          item_wrapper: "question-checkbox-group-item-wrapper",
          input: "question-checkbox-group-input",
          label: "question-checkbox-group-label"
        },
        error_display: {
          container: "question-error-display",
          title: "question-error-display-title",
          list: "question-error-display-list"
        }
      }.freeze

      def initialize(custom_classes = {})
        @classes = deep_merge(CLASS_STRUCTURE, custom_classes)
      end

      # Get classes for a specific section and optional key
      def get(section, key = nil)
        if key
          @classes.dig(section, key) || ""
        else
          @classes[section] || ""
        end
      end

      # Get all classes for debugging/inspection
      def all_classes
        @classes
      end

      # Check if a section/key exists
      def exists?(section, key = nil)
        if key
          @classes.dig(section, key) != nil
        else
          @classes.key?(section)
        end
      end

      private

      # Deep merge helper to merge custom classes with structure
      # Concatenates string values when both default and custom exist
      def deep_merge(hash1, hash2)
        hash1.merge(hash2) do |key, oldval, newval|
          if oldval.is_a?(Hash) && newval.is_a?(Hash)
            deep_merge(oldval, newval)
          elsif oldval.is_a?(String) && newval.is_a?(String)
            # Concatenate classes: default structural classes + custom styling classes
            [oldval, newval].reject(&:empty?).join(" ")
          else
            newval.presence || oldval
          end
        end
      end
    end
  end
end