require_dependency "avo/application_controller"

module Avo
  class SearchController < ApplicationController
    include Rails.application.routes.url_helpers
    include ActionView::Helpers::TextHelper

    before_action :set_resource_name, only: :show
    before_action :set_resource, only: :show

    def show
      render json: search_resources([resource])
    rescue => error
      render_search_error(error)
    end

    private

    def search_resources(resources)
      resources
        .map do |resource|
          # Apply authorization
          next unless @authorization.set_record(resource.model_class).authorize_action(:search, raise_exception: false)
          # Filter out the models without a search_query
          next if resource.search_query.nil?

          search_resource resource
        end
        .select do |payload|
          payload.present?
        end
        .sort_by do |payload|
          payload.last[:count]
        end
        .reverse
        .to_h
    end

    def search_resource(resource)
      query = Avo::ExecutionContext.new(
        target: resource.search_query,
        params: params,
        query: resource.query_scope
      ).handle

      query = apply_scope(query) if should_apply_any_scope?

      # Get the count
      results_count = query.reselect(resource.model_class.primary_key).count

      # Get the results
      query = query.limit(8)

      results = apply_search_metadata(query, resource)

      header = resource.plural_name

      if results_count > 0
        header = "#{header} (#{results_count})"
      end

      result_object = {
        header: header,
        help: resource.fetch_search(:help) || "",
        results: results,
        count: results.count
      }

      [resource.name.pluralize.downcase, result_object]
    end

    # When searching in a `has_many` association and will scope out the records against the parent record.
    # This is also used when looking for `belongs_to` associations, and this method applies the parents `attach_scope` if present.
    def apply_scope(query)
      if should_apply_has_many_scope?
        apply_has_many_scope
      elsif should_apply_attach_scope?
        apply_attach_scope(query, parent)
      end
    end

    # Parent passed as argument to be used as a variable instead of the method "def parent"
    # Otherwise parent = params...safe_constantize... will try to call method "def parent="
    def apply_attach_scope(query, parent)
      # If the parent is nil it probably means that someone's creating the record so it's not attached yet.
      # In these scenarios, try to find the grandparent for the new views where the parent is nil
      # and initialize the parent record with the grandparent attached so the user has the required information
      # to scope the query.
      # Example usage: Got to a project, create a new review, and search for a user.
      if parent.blank? && params[:via_parent_resource_id].present? && params[:via_parent_resource_class].present? && params[:via_relation].present?
        parent_resource_class = BaseResource.get_model_by_name params[:via_parent_resource_class]

        reflection_class = BaseResource.get_model_by_name params[:via_reflection_class]

        grandparent = parent_resource_class.find params[:via_parent_resource_id]
        parent = reflection_class.new(
          params[:via_relation] => grandparent
        )
      end

      Avo::ExecutionContext.new(target: attach_scope, query: query, parent: parent).handle
    end

    # This scope is applied if the search is being performed on a has_many association
    def apply_has_many_scope
      association_name = BaseResource.valid_association_name(parent, params[:via_association_id])

      # Get association records
      query = parent.send(association_name)

      # Apply policy scope if authorization is present
      query = resource.authorization&.apply_policy query

      Avo::ExecutionContext.new(target: @resource.class.search_query, params: params, query: query).handle
    end

    def apply_search_metadata(records, avo_resource)
      records.map do |record|
        resource = avo_resource.new(record: record)

        fetch_result_information record, resource, resource.class.fetch_search(:item, record: record)
      end
    end

    def fetch_result_information(record, resource, item)
      highlighted_title = highlight(item&.dig(:title) || resource.record_title&.to_s, params[:q])
      {
        _id: record.id,
        _label: highlighted_title,
        _url: resource.class.fetch_search(:result_path, record: resource.record) || resource.record_path
      }
    end

    def should_apply_has_many_scope?
      params[:via_association] == "has_many" && @resource.class.search_query.present?
    end

    def should_apply_attach_scope?
      params[:via_association] == "belongs_to" && attach_scope.present?
    end

    def should_apply_any_scope?
      should_apply_has_many_scope? || should_apply_attach_scope?
    end

    def attach_scope
      @attach_scope ||= field&.attach_scope
    end

    def field
      @field ||= fetch_field
    end

    def parent
      @parent ||= fetch_parent
    end

    def fetch_field
      return if params[:via_association_id].nil?

      reflection_resource = Avo.resource_manager.get_resource_by_model_class(params[:via_reflection_class]).new(
        view: Avo::ViewInquirer.new(params[:via_reflection_view]),
        record: parent,
        params: params,
        user: _current_user
      )

      reflection_resource.detect_fields.get_field_definitions.find do |field|
        field.id.to_s == params[:via_association_id]
      end
    end

    def fetch_parent
      return unless params[:via_reflection_id].present?

      parent_resource = Avo.resource_manager.get_resource_by_model_class params[:via_reflection_class]
      parent_resource.find_record params[:via_reflection_id], params: params
    end

    def render_search_error(error)
      raise error unless Rails.env.development?

      render json: {
        error: {
          header: "🚨 An error occurred while searching. 🚨",
          help: "Please see the error and fix it before deploying.",
          results: {
            _label: error.message
          },
          count: 1
        }
      }, status: 500
    end
  end
end