<?php 

// Register store.
acf_register_store( 'hook-variations' );

/**
 * acf_add_filter_variations
 *
 * Registers variations for the given filter.
 *
 * @date	26/1/19
 * @since	5.7.11
 *
 * @param	string $filter The filter name.
 * @param	array $variations An array variation keys.
 * @param	int $index The param index to find variation values.
 * @return	void
 */
function acf_add_filter_variations( $filter = '', $variations = array(), $index = 0 ) {
	
	// Store replacement data.
	acf_get_store('hook-variations')->set( $filter, array(
		'type'			=> 'filter',
		'variations' 	=> $variations,
		'index' 		=> $index,
	));
	
	// Add generic handler.
	// Use a priotiry of 10, and accepted args of 10 (ignored by WP).
	add_filter( $filter, '_acf_apply_hook_variations', 10, 10 );
}

/**
 * acf_add_action_variations
 *
 * Registers variations for the given action.
 *
 * @date	26/1/19
 * @since	5.7.11
 *
 * @param	string $action The action name.
 * @param	array $variations An array variation keys.
 * @param	int $index The param index to find variation values.
 * @return	void
 */
function acf_add_action_variations( $action = '', $variations = array(), $index = 0 ) {
	
	// Store replacement data.
	acf_get_store('hook-variations')->set( $action, array(
		'type'			=> 'action',
		'variations' 	=> $variations,
		'index' 		=> $index,
	));
	
	// Add generic handler.
	// Use a priotiry of 10, and accepted args of 10 (ignored by WP).
	add_action( $action, '_acf_apply_hook_variations', 10, 10 );
}

/**
 * _acf_apply_hook_variations
 *
 * Applys hook variations during apply_filters() or do_action().
 *
 * @date	25/1/19
 * @since	5.7.11
 *
 * @param	mixed
 * @return	mixed
 */
function _acf_apply_hook_variations() {
	
	// Get current filter.
	$filter = current_filter();
	
	// Get args provided.
	$args = func_get_args();
	
	// Get variation information.
	$variations = acf_get_store('hook-variations')->get( $filter );
	extract( $variations );
	
	// Find field in args using index.
	$field = $args[ $index ];
	
	// Loop over variations and apply filters.
	foreach( $variations as $variation ) {
		
		// Get value from field.
		// First look for "backup" value ("_name", "_key").
		if( isset($field[ "_$variation" ]) ) {
			$value = $field[ "_$variation" ];
		} elseif( isset($field[ $variation ]) ) {
			$value = $field[ $variation ];
		} else {
			continue;
		}
		
		// Apply filters.
		if( $type === 'filter' ) {
			$args[0] = apply_filters_ref_array( "$filter/$variation=$value", $args );
		
		// Or do action.
		} else {
			do_action_ref_array( "$filter/$variation=$value", $args );
		}
	}
	
	// Return first arg.
	return $args[0];
}

// Register store.
acf_register_store( 'deprecated-hooks' );

/**
 * acf_add_deprecated_filter
 *
 * Registers a deprecated filter to run during the replacement.
 *
 * @date	25/1/19
 * @since	5.7.11
 *
 * @param	string $deprecated The deprecated hook.
 * @param	string $version The version this hook was deprecated.
 * @param	string $replacement The replacement hook.
 * @return	void
 */
function acf_add_deprecated_filter( $deprecated, $version, $replacement ) {
	
	// Store replacement data.
	acf_get_store('deprecated-hooks')->append(array(
		'type'			=> 'filter',
		'deprecated' 	=> $deprecated,
		'replacement' 	=> $replacement,
		'version'		=> $version
	));
	
	// Add generic handler.
	// Use a priotiry of 10, and accepted args of 10 (ignored by WP).
	add_filter( $replacement, '_acf_apply_deprecated_hook', 10, 10 );
}

/**
 * acf_add_deprecated_action
 *
 * Registers a deprecated action to run during the replacement.
 *
 * @date	25/1/19
 * @since	5.7.11
 *
 * @param	string $deprecated The deprecated hook.
 * @param	string $version The version this hook was deprecated.
 * @param	string $replacement The replacement hook.
 * @return	void
 */
function acf_add_deprecated_action( $deprecated, $version, $replacement ) {
	
	// Store replacement data.
	acf_get_store('deprecated-hooks')->append(array(
		'type'			=> 'action',
		'deprecated' 	=> $deprecated,
		'replacement' 	=> $replacement,
		'version'		=> $version
	));
	
	// Add generic handler.
	// Use a priotiry of 10, and accepted args of 10 (ignored by WP).
	add_filter( $replacement, '_acf_apply_deprecated_hook', 10, 10 );
}

/**
 * _acf_apply_deprecated_hook
 *
 * Applys a deprecated filter during apply_filters() or do_action().
 *
 * @date	25/1/19
 * @since	5.7.11
 *
 * @param	mixed
 * @return	mixed
 */
function _acf_apply_deprecated_hook() {
	
	// Get current hook.
	$hook = current_filter();
	
	// Get args provided.
	$args = func_get_args();
	
	// Get deprecated items for this hook.
	$items = acf_get_store('deprecated-hooks')->query(array( 'replacement' => $hook ));
	
	// Loop over results.
	foreach( $items as $item ) {
		
		// Extract data.
		extract( $item );
		
		// Check if anyone is hooked into this deprecated hook.
		if( has_filter($deprecated) ) {
			
			// Log warning.
			//_deprecated_hook( $deprecated, $version, $hook );
		
			// Apply filters.
			if( $type === 'filter' ) {
				$args[0] = apply_filters_ref_array( $deprecated, $args );
			
			// Or do action.
			} else {
				do_action_ref_array( $deprecated, $args );
			}
		}
	}
	
	// Return first arg.
	return $args[0];
}