<?php

################################################################################################
# Comment out/in as required

// IE 6 shims
CssCrush::addRuleMacro( 'csscrush_minheight' );

// IE 6/7 shims
CssCrush::addRuleMacro( 'csscrush_clip' );
CssCrush::addRuleMacro( 'csscrush_display_inlineblock' );

// IE filter
CssCrush::addRuleMacro( 'csscrush_filter' );

// RGBA fallback
CssCrush::addRuleMacro( 'csscrush_rgba' );

// HSL for all browsers
CssCrush::addRuleMacro( 'csscrush_hsl' );


################################################################################################

/**
 * Simulate inline-block in IE < 8
 * 
 * Before: 
 *     display: inline-block;
 * 
 * After:
 *     display: inline-block;
 *     *display: inline;
 *     *zoom: 1;
 */
function csscrush_display_inlineblock ( CssCrush_Rule $rule ) {
	if ( $rule->propertyCount( 'display' ) < 1 ) {
		return;
	}
	$new_set = array();
	foreach ( $rule as $declaration ) {
		$new_set[] = $declaration;
		$is_display = $declaration->property === 'display';
		if ( !$is_display or $is_display and $declaration->value !== 'inline-block' ) {
			continue;
		}
		$new_set[] = $rule->createDeclaration( '*display', 'inline' );
		$new_set[] = $rule->createDeclaration( '*zoom', 1 );
	}
	$rule->declarations = $new_set;
}

/**
 * Fix min-height in IE 6
 * 
 * Before: 
 *     min-height: 100px;
 * 
 * After:
 *     min-height: 100px;
 *     _height: 100px;
 */
function csscrush_minheight ( CssCrush_Rule $rule ) {
	if ( $rule->propertyCount( 'min-height' ) < 1 ) {
		return;
	}
	$new_set = array();
	foreach ( $rule as $declaration ) {
		$new_set[] = $declaration;
		if ( $declaration->property !== 'min-height' ) {
			continue;
		}
		$new_set[] = $rule->createDeclaration( '_height', $declaration->value );
	}
	$rule->declarations = $new_set;
}

/**
 * Fix clip syntax for IE < 8
 * 
 * Before: 
 *     clip: rect(1px,1px,1px,1px);
 * 
 * After:
 *     clip: rect(1px,1px,1px,1px);
 *     *clip: rect(1px 1px 1px 1px);
 */
function csscrush_clip ( CssCrush_Rule $rule ) {
	// Assume it's been dealt with if the property occurs more than once 
	if ( $rule->propertyCount( 'clip' ) !== 1 ) {
		return;
	}
	$new_set = array();
	foreach ( $rule as $declaration ) {
		$new_set[] = $declaration;
		if ( $declaration->property !== 'clip' ) {
			continue;
		}
		$new_set[] = $rule->createDeclaration( 
						'*clip', str_replace( ',', ' ', $rule->getDeclarationValue( $declaration ) ) );
	}
	$rule->declarations = $new_set;
}

/**
 * IE filter without the cruft
 */
function csscrush_filter ( CssCrush_Rule $rule ) {
	if ( $rule->propertyCount( 'filter' ) < 1 ) {
		return;
	}
	$filter_prefix = 'progid:DXImageTransform.Microsoft.';
	$new_set = array();
	foreach ( $rule as $declaration ) {
		if ( $declaration->property !== 'filter' ) {
			$new_set[] = $declaration;
			continue;
		}
		$list = array_map( 'trim', explode( ',', $declaration->value ) );
		foreach ( $list as &$item ) {
			if ( 
				strpos( $item, $filter_prefix ) !== 0 and 
				strpos( $item, 'alpha' ) !== 0 // Shortcut syntax permissable on alpha
			) {
				$item = $filter_prefix . ucfirst( $item );
			}
		}
		$declaration->value = implode( ',', $list );
		if ( !$rule->propertyCount( 'zoom' ) ) {
			// Filters need hazLayout
			$new_set[] = $rule->createDeclaration( 'zoom', 1 );
		}
		$new_set[] = $declaration;
		$new_set[] = $rule->createDeclaration( '-ms-filter', "\"$declaration->value\"" );
	}
	$rule->declarations = $new_set;
}

/**
 * RGBA fallback
 * Only works with background shorthand IE < 8 
 * (http://css-tricks.com/2151-rgba-browser-support/)
 * 
 * Before: 
 *     background: rgba(0,0,0,.5);
 * 
 * After:
 *     background: rgb(0,0,0);
 *     background: rgba(0,0,0,.5);
 */
function csscrush_rgba ( CssCrush_Rule $rule ) {
	$props = array_keys( $rule->properties );

	// Determine which properties apply
	$rgba_props = array();
	foreach ( $props as $prop ) {
		if ( $prop === 'background' or strpos( $prop, 'color' ) !== false ) {
			$rgba_props[] = $prop;
		}
	}
	if ( empty( $rgba_props ) ) {
		return;
	}

	$new_set = array();
	foreach ( $rule as $declaration ) {
		$is_viable = in_array( $declaration->property, $rgba_props );
		if ( 
			!$is_viable or 
			$is_viable and !preg_match( '!^rgba___p\d+___$!', $declaration->value )
		) {
			$new_set[] = $declaration;
			continue;
		}
		// Create rgb value from rgba
		$raw_value = $rule->getDeclarationValue( $declaration );
		$raw_value = substr( $raw_value, 5, strlen( $raw_value ) - 1 );
		list( $r, $g, $b, $a ) = explode( ',', $raw_value );
		
		// Add rgb value to the stack, followed by rgba 
		$new_set[] = $rule->createDeclaration( $declaration->property, "rgb($r,$g,$b)" );
		$new_set[] = $declaration;
	}
	$rule->declarations = $new_set;
}

/**
 * HSL shim
 * Converts HSL values into hex code that works in all browsers
 * 
 * Before:
 *     color: hsl( 100, 50%, 50% )
 * 
 * After:
 *    color: #6abf40
 */
function csscrush_hsl ( CssCrush_Rule $rule ) {
	foreach ( $rule as &$declaration ) {
		if ( !empty( $declaration->functions ) and in_array( 'hsl', $declaration->functions ) ) {
			while ( preg_match( '!hsl(___p\d+___)!', $declaration->value, $m ) ) {
				$full_match = $m[0];
				$token = $m[1];
				$hsl = trim( $rule->parens[ $token ], '()' );
				$hsl = array_map( 'trim', explode( ',', $hsl ) );
				$hex = CssCrush_Color::cssHslToHex( $hsl );
				$declaration->value = str_replace( $full_match, $hex, $declaration->value );
			}
		}
	}
}