<?php

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}
/**
 * EpicFormBuilder Model.
 *
 * @package epicformbuilder/models
 */

require_once __DIR__ . '/../class-epicformbuilder-model.php';
require_once __DIR__ . '/../services/class-epicformbuilder-services-submission-merge.php';

/**
 * EpicFormBuilder Mode.
 *
 * Statistics model.
 */
class Epicformbuilder_Models_Statistics implements Epicformbuilder_Model {

	/**
	 * Form ID.
	 *
	 * @var string
	 */
	public string $form_uid;

	/**
	 * Aggregated statistics.
	 *
	 * @var array
	 */
	public array $json = [];

	public DateTimeInterface $created_utc;

	/**
	 * Increments form statistics.
	 *
	 * @param Epicformbuilder_Models_Submission $submission The submission.
	 * @param Epicformbuilder_Models_Form       $form       The form.
	 *
	 * @return $this
	 * @throws Exception If date time cannot be created.
	 */
	public function process( $submission, $form ) {
		/*
		 * search form structure if there are any multi value fields
		 * e.g. dropdowns, checkboxes, radios
		 */
		/**
		 * Filters the components whose options are tallied in form statistics.
		 * Add-ons append their own choice-style components here.
		 *
		 * @since 1.0.0
		 *
		 * @param string[] $components Component names.
		 */
		$multi_value_fields = (array) apply_filters(
			'epicforms_statistics_multi_value_components',
			[
				Epicformbuilder_Models_Form_Json_Field::TYPE_SELECT,
				Epicformbuilder_Models_Form_Json_Field::TYPE_CHECKBOX,
				Epicformbuilder_Models_Form_Json_Field::TYPE_RADIO,
			]
		);

		$multi = array_reduce(
			$form->json->steps,
			function ( $acc, $step ) use ( $multi_value_fields ) {
				return array_merge(
					$acc,
					array_reduce(
						$step->fields,
						function ( $acc, $field ) use ( $multi_value_fields ) {
							if ( in_array( $field->component, $multi_value_fields, true ) ) {
								$acc[ $field->id ] = [
									'label'   => $field->label ?? $field->placeholder,
									'options' => array_fill_keys(
										array_map(
											function ( $o ) {
												return $o['label'] ?? $o;
											},
											(array) ( $field->options ?? [] )
										),
										0
									),
								];
							}
							return $acc;
						},
						[]
					)
				);
			},
			[]
		);

		/* If statistics record doesn't exist for this form - create it */
		if ( empty( $this->json ) ) {
			$this->json = [
				'submissions' => array_fill( 0, 24, 0 ),
				'fields'      => $multi,
			];
		} else {
			/*
			 * If there are any new multi choice fields in the form or
			 * fields got new options - we add those into aggregated
			 * statistics records
			 */
			foreach ( $multi as $key => $data ) {
				if ( ! isset( $this->json['fields'][ $key ] ) ) {
					$this->json['fields'][ $key ] = $data;
				}
				foreach ( $data['options'] as $option => $value ) {
					if ( ! isset( $this->json['fields'][ $key ]['options'][ $option ] ) ) {
						$this->json['fields'][ $key ]['options'][ $option ] = 0;
					}
				}
			}
		}

		$submission_fields = array_keys( $submission->json );
		$submission->json = array_reduce(
			$submission_fields,
			function ( $acc, $key ) use ( $submission, $multi ) {
				// We are only interested in multi value fields.
				if ( isset( $multi[ $key ] ) ) {
					if ( is_array( $submission->json[ $key ] ) ) {
						$val = array_map(
							function ( $value ) {
								return $value['label'] ?? $value;
							},
							$submission->json[ $key ]
						);
					} else {
						$val = [ $submission->json[ $key ] ];
					}
					$acc[ $key ] = $val;
				}
				return $acc;
			},
			[]
		);

		$hour = ( new DateTimeImmutable( 'now', new DateTimeZone( 'UTC' ) ) )->format( 'H' );
		$this->json['submissions'][ intval( $hour ) ] += 1;
		foreach ( $submission->json as $field => $value ) {
			// Defence in depth: guard against the reserved upload-locator
			// sidecar (Epicformbuilder_Services_Submission_Merge::META_KEY).
			// Currently unreachable because the loop above filters
			// submission->json down to declared multi-choice fields before
			// this iteration, so the sidecar never appears here.
			if ( Epicformbuilder_Services_Submission_Merge::META_KEY === $field ) {
				continue;
			}

			/*
			 * An array is either a list of chosen options or, for some
			 * add-on components, a single item object carrying a label.
			 */
			if ( is_array( $value ) ) {
				if ( isset( $value['label'] ) ) {
					$this->increment( $multi, $field, $value['label'] );
				} else {
					foreach ( $value as $v ) {
						$this->increment( $multi, $field, $v );
					}
				}
			} else {
				$this->increment( $multi, $field, $value );
			}
		}
		return $this;
	}

	/**
	 * Increment statistics on multi fields values.
	 *
	 * @param array  $multi Multi fields.
	 * @param string $field Field ID.
	 * @param string $value Field value.
	 */
	public function increment( $multi, $field, $value ) {
		if ( ! isset( $multi[ $field ]['options'][ $value ] ) ) {
			if ( ! isset( $this->json['fields'][ $field ]['options']['other_option'] ) ) {
				$this->json['fields'][ $field ]['options']['other_option'] = 0;
			} else {
				$this->json['fields'][ $field ]['options']['other_option'] += 1;
			}
		} else {
			$this->json['fields'][ $field ]['options'][ $value ] += 1;
		}
	}
}