require 'json-schema'
module Ecom
  module Core
    class TaskTemplate < ApplicationRecord
      TASK_STEP_SCHEMA = {
        'type' => 'object',
        'required' => %w[name total_contribution_percentage_to_task],
        'additionalProperties' => false,
        'properties' => {
          'name' => { 'type' => 'string' },
          'total_contribution_percentage_to_task' => {
            'type' => 'integer',
            'minimum' => 1,
            'maximum' => 100
          }
        }
      }.freeze

      # here the json schema has a bug ( including all properties as required)
      # and because task_step_name is required on a condition ( only if the
      # milestone is after a task step ), we can solve this with a workaround
      # by specifying task_step_name in patternProperties.
      MILESTONE_SCHEMA = {
        'type' => 'object',
        'required' => %w[name is_after_task_step],
        'additionalProperties' => false,
        'properties' => {
          'name' => { 'type' => 'string' },
          'is_after_task_step' => {
            'type' => 'boolean'
          }
        },
        "patternProperties": {
          "task_step_name": {
            'type' => 'string'
          }
        }
      }.freeze

      has_ancestry

      belongs_to :task_template_type
      has_and_belongs_to_many :work_product_templates, join_table: 'ecom_core_task_templates_work_product_templates'
      has_and_belongs_to_many :resource_types, join_table: 'ecom_core_task_templates_resource_types'
      belongs_to :takeoff_calculator, optional: true

      validates :name, :code, presence: true
      validates :code, uniqueness: true
      delegate(:name, to: :task_template_type, prefix: true)

      validate :task_steps_schema_validator
      validate :milestones_schema_validator
      validate :validate_sum_of_task_step_contribution
      validate :validate_milestone_task_step_association

      def full_name
        parent_name = parent&.name
        return name unless parent_name

        "#{name} - #{parent_name}"
      end

      def crew_types
        resource_types.where(type: 'Ecom::Core::CrewType')
      end

      def material_types
        resource_types.where(type: 'Ecom::Core::MaterialType')
      end

      def equipment_types
        resource_types.where(type: 'Ecom::Core::EquipmentType')
      end

      def task_steps_schema_validator
        return if task_steps.nil?

        validation_errors = JSON::Validator.fully_validate(TASK_STEP_SCHEMA,
                                                           task_steps, strict: true,
                                                                       list: true, clear_cache: true)

        errors.add(:task_steps, validation_errors) unless validation_errors.empty?
      end

      def milestones_schema_validator
        return if milestones.nil?

        validation_errors = JSON::Validator.fully_validate(MILESTONE_SCHEMA,
                                                           milestones, strict: true,
                                                                       list: true, clear_cache: true)

        errors.add(:milestones, validation_errors) unless validation_errors.empty?
      end

      def validate_sum_of_task_step_contribution
        return if task_steps.nil?

        filtered_task_steps = task_steps.select { |task_step| task_step['total_contribution_percentage_to_task'] }

        sum_of_task_step_contribution =
          filtered_task_steps.sum { |task_step| task_step['total_contribution_percentage_to_task'] }

        errors.add(:task_steps, 'Sum of task step contributions has to be 100') if sum_of_task_step_contribution != 100
      end

      def validate_milestone_task_step_association
        return if milestones.nil?

        task_step_names = task_steps&.map { |task_step| task_step['name'] }

        milestones_associated_with_task_step = milestones.select { |milestone| milestone['is_after_task_step'] }

        milestones_associated_with_task_step.each do |milestone|
          if milestone['task_step_name'].nil?
            errors.add(:milestones, 'if the milestone is after a task step, please specify the task step name')
            next
          end

          unless task_step_names.include? milestone['task_step_name']
            errors.add(:milestone, 'task step for the given milestone does not exist in list of task steps')
          end
        end
      end
    end
  end
end