<?php
namespace Digiter\BuilderStudio;
defined('ABSPATH') || exit;

/**
 * Allowlisted visual surfaces and button treatments.
 *
 * This class stores only typed values. Preset implementations remain in the
 * plugin stylesheet, while the renderer receives scoped classes and safe CSS
 * custom properties. Arbitrary CSS and arbitrary background URLs are never
 * accepted here.
 */
final class Appearance {
    public const PRESETS = [
        'none','canvas','soft-mist','deep-ink','accent-wash','duo-flow',
        'radial-glow','aurora-mesh','horizon','prism','clear-glass',
        'frosted-glass','tinted-glass','smoked-glass','champagne-gold',
        'brushed-gold','rose-gold','silver','titanium','copper',
        'diamond-light','crystal','pearl','liquid-metal','onyx','sapphire','emerald','ruby',
        'amethyst','holographic','neon-edge','soft-ui','clay',
        'editorial-paper','linen','carbon','fine-grain','dot-grid',
    ];
    public const MODES = ['none','solid','linear','radial','conic','image'];
    public const IMAGE_SIZES = ['cover','contain','auto'];
    public const IMAGE_REPEATS = ['no-repeat','repeat','repeat-x','repeat-y','space','round'];
    public const ATTACHMENTS = ['scroll','fixed','local'];
    public const BLENDS = [
        'normal','multiply','screen','overlay','darken','lighten','color-dodge',
        'color-burn','hard-light','soft-light','difference','exclusion','hue',
        'saturation','color','luminosity',
    ];
    public const PATTERNS = ['none','grain','dots','grid','lines','diamond'];
    public const MOTIONS = ['none','drift','pulse','shimmer'];

    public const BUTTON_PRESETS = [
        'inherit','classic','gradient','glass','frosted','gold','rose-gold','silver','diamond','pearl','holographic','neon','raised','pressed','soft-ui','clay','brutalist','pill','minimal-line','underline','outline','soft','text','flat','square','capsule','bevel','embossed','leather','carbon','steel','titanium','copper','bronze','obsidian','sapphire','emerald','ruby','ocean','sunset','aurora','candy','fire','ice','dark-glass','glass-outline','double-border','dashed','corner-cut','terminal','retro','arcade','sticker','ribbon','spotlight','gradient-border','soft-shadow','floating','hover-sweep','animated-gradient','glossy'
    ];
    public const BUTTON_TEXT_TONES = ['auto','light','dark','custom'];
    public const BUTTON_EFFECTS = ['none','lift','glow','shine','fill-slide','icon-shift','press'];

    public static function defaults(): array {
        return [
            'version'=>1,
            'preset'=>'none',
            'mode'=>'none',
            'color1'=>'',
            'color2'=>'',
            'color3'=>'',
            'angle'=>135,
            'image'=>Document::image([]),
            'imageSize'=>'cover',
            'imageRepeat'=>'no-repeat',
            'attachment'=>'scroll',
            'overlay'=>'',
            'overlayOpacity'=>0,
            'blend'=>'normal',
            'blur'=>0,
            'pattern'=>'none',
            'patternOpacity'=>15,
            'motion'=>'none',
        ];
    }

    public static function clean($raw): array {
        $defaults=self::defaults();
        if(!is_array($raw) || (int)($raw['version']??1)!==1){return $defaults;}
        $mode=Document::choice($raw['mode']??'',self::MODES,$defaults['mode']);
        $preset=Document::choice($raw['preset']??'',self::PRESETS,$defaults['preset']);
        if($mode!=='none'){$preset='none';}
        return [
            'version'=>1,
            'preset'=>$preset,
            'mode'=>$mode,
            'color1'=>Document::color($raw['color1']??''),
            'color2'=>Document::color($raw['color2']??''),
            'color3'=>Document::color($raw['color3']??''),
            'angle'=>Document::number($raw['angle']??$defaults['angle'],0,360),
            'image'=>Document::image($raw['image']??[]),
            'imageSize'=>Document::choice($raw['imageSize']??'',self::IMAGE_SIZES,$defaults['imageSize']),
            'imageRepeat'=>Document::choice($raw['imageRepeat']??'',self::IMAGE_REPEATS,$defaults['imageRepeat']),
            'attachment'=>Document::choice($raw['attachment']??'',self::ATTACHMENTS,$defaults['attachment']),
            'overlay'=>Document::color($raw['overlay']??''),
            'overlayOpacity'=>Document::number($raw['overlayOpacity']??$defaults['overlayOpacity'],0,100),
            'blend'=>Document::choice($raw['blend']??'',self::BLENDS,$defaults['blend']),
            'blur'=>Document::number($raw['blur']??$defaults['blur'],0,40),
            'pattern'=>Document::choice($raw['pattern']??'',self::PATTERNS,$defaults['pattern']),
            'patternOpacity'=>Document::number($raw['patternOpacity']??$defaults['patternOpacity'],0,100),
            'motion'=>Document::choice($raw['motion']??'',self::MOTIONS,$defaults['motion']),
        ];
    }

    public static function defaults_button(): array {
        return [
            'version'=>1,
            'preset'=>'inherit',
            'color1'=>'',
            'color2'=>'',
            'textTone'=>'auto',
            'textColor'=>'',
            'hoverColor1'=>'',
            'hoverColor2'=>'',
            'hoverTextColor'=>'',
            'borderColor'=>'',
            'hoverBorderColor'=>'',
            'radius'=>-1,
            'paddingX'=>0,
            'paddingY'=>0,
            'weight'=>0,
            'letterSpacing'=>0,
            'glow'=>0,
            'effect'=>'none',
            'transition'=>180,
        ];
    }

    /** Backwards-compatible spelling used by the document schema. */
    public static function button_defaults(): array {
        return self::defaults_button();
    }

    public static function clean_button($raw): array {
        $defaults=self::defaults_button();
        if(!is_array($raw) || (int)($raw['version']??1)!==1){return $defaults;}
        return [
            'version'=>1,
            'preset'=>Document::choice($raw['preset']??'',self::BUTTON_PRESETS,$defaults['preset']),
            'color1'=>Document::color($raw['color1']??''),
            'color2'=>Document::color($raw['color2']??''),
            'textTone'=>Document::choice($raw['textTone']??'',self::BUTTON_TEXT_TONES,$defaults['textTone']),
            'textColor'=>Document::color($raw['textColor']??''),
            'hoverColor1'=>Document::color($raw['hoverColor1']??''),
            'hoverColor2'=>Document::color($raw['hoverColor2']??''),
            'hoverTextColor'=>Document::color($raw['hoverTextColor']??''),
            'borderColor'=>Document::color($raw['borderColor']??''),
            'hoverBorderColor'=>Document::color($raw['hoverBorderColor']??''),
            'radius'=>Document::number($raw['radius']??$defaults['radius'],-1,999),
            'paddingX'=>Document::number($raw['paddingX']??$defaults['paddingX'],0,80),
            'paddingY'=>Document::number($raw['paddingY']??$defaults['paddingY'],0,80),
            'weight'=>Document::number($raw['weight']??$defaults['weight'],0,900),
            'letterSpacing'=>Document::number($raw['letterSpacing']??$defaults['letterSpacing'],-2,8),
            'glow'=>Document::number($raw['glow']??$defaults['glow'],0,60),
            'effect'=>Document::choice($raw['effect']??'',self::BUTTON_EFFECTS,$defaults['effect']),
            'transition'=>Document::number($raw['transition']??$defaults['transition'],0,600),
        ];
    }

    /** Return scoped renderer values for a document or node surface. */
    public static function attributes($raw): array {
        return self::surface_attributes($raw);
    }

    public static function surface_attributes($raw): array {
        $a=self::clean($raw);
        $active=$a['preset']!=='none'||$a['mode']!=='none'||$a['pattern']!=='none'||$a['motion']!=='none'||$a['overlay']!==''||$a['blur']>0||$a['blend']!=='normal';
        if(!$active){return ['class'=>'','style'=>''];}

        $classes=['dbs-surface'];
        if($a['preset']!=='none'){$classes[]='dbs-surface-'.$a['preset'];}
        if($a['mode']!=='none'){$classes[]='dbs-surface-mode-'.$a['mode'];}
        if($a['pattern']!=='none'){$classes[]='dbs-surface-pattern-'.$a['pattern'];}
        if($a['motion']!=='none'){$classes[]='dbs-surface-motion-'.$a['motion'];}
        if(in_array($a['mode'],['solid','linear','radial','conic'],true)){
            $author_colors=array_values(array_filter([$a['color1'],$a['color2'],$a['color3']],static fn($color)=>$color!==''));
            if($author_colors){$classes[]='dbs-surface-tone-auto-'.self::automatic_tone($author_colors);}
        }

        $css=[];
        foreach(['color1'=>'--dbs-surface-color-1','color2'=>'--dbs-surface-color-2','color3'=>'--dbs-surface-color-3'] as $key=>$property){
            if($a[$key]!==''){$css[]=$property.':'.$a[$key];}
        }
        if(in_array($a['mode'],['linear','conic'],true)){$css[]='--dbs-surface-angle:'.self::number_text($a['angle']).'deg';}
        if($a['mode']==='image' && $a['image']['url']!==''){
            $css[]='--dbs-surface-image:url("'.self::css_url($a['image']['url']).'")';
            $css[]='--dbs-surface-image-size:'.$a['imageSize'];
            $css[]='--dbs-surface-image-repeat:'.$a['imageRepeat'];
            $css[]='--dbs-surface-attachment:'.$a['attachment'];
            $css[]='--dbs-surface-position:'.self::number_text($a['image']['x']).'% '.self::number_text($a['image']['y']).'%';
        }
        if($a['overlay']!==''){
            $css[]='--dbs-surface-overlay:'.$a['overlay'];
            $css[]='--dbs-surface-overlay-opacity:'.self::ratio($a['overlayOpacity']);
        }
        if($a['blend']!=='normal'){$css[]='--dbs-surface-blend:'.$a['blend'];}
        if($a['blur']>0){$css[]='--dbs-surface-blur:'.self::number_text($a['blur']).'px';}
        if($a['pattern']!=='none'){$css[]='--dbs-surface-pattern-opacity:'.self::ratio($a['patternOpacity']);}
        return ['class'=>implode(' ',$classes),'style'=>self::style($css)];
    }

    /** Return scoped renderer values for one button or a button wrapper. */
    public static function button_attributes($raw): array {
        $b=self::clean_button($raw);
        $defaults=self::defaults_button();
        $colors=['color1','color2','textColor','hoverColor1','hoverColor2','hoverTextColor','borderColor','hoverBorderColor'];
        $hasColor=false;foreach($colors as $key){if($b[$key]!==''){$hasColor=true;break;}}
        $active=$b['preset']!=='inherit'||$b['textTone']!=='auto'||$b['effect']!=='none'||$hasColor||$b['radius']>=0||$b['paddingX']>0||$b['paddingY']>0||$b['weight']>0||$b['letterSpacing']!=0||$b['glow']>0||$b['transition']!=$defaults['transition'];
        if(!$active){return ['class'=>'','style'=>''];}

        $classes=['dbs-button-style-local'];
        if($b['preset']!=='inherit'){$classes[]='dbs-button-preset-'.$b['preset'];}
        if($b['textTone']!=='auto'){$classes[]='dbs-button-tone-'.$b['textTone'];}
        elseif($b['textColor']===''&&($b['color1']!==''||$b['color2']!=='')){$classes[]='dbs-button-tone-auto-'.self::automatic_button_tone($b);}
        if($b['textTone']==='auto'&&$b['hoverTextColor']===''&&($b['hoverColor1']!==''||$b['hoverColor2']!=='')){
            $classes[]='dbs-button-hover-tone-auto-'.self::automatic_tone(array_values(array_filter([$b['hoverColor1'],$b['hoverColor2']],static fn($color)=>$color!=='')));
        }
        if($b['effect']!=='none'){$classes[]='dbs-button-effect-'.$b['effect'];}

        $css=[];
        $properties=[
            'color1'=>'--dbs-button-color-1','color2'=>'--dbs-button-color-2',
            'textColor'=>'--dbs-button-text-local','hoverColor1'=>'--dbs-button-hover-color-1',
            'hoverColor2'=>'--dbs-button-hover-color-2','hoverTextColor'=>'--dbs-button-hover-text',
            'borderColor'=>'--dbs-button-border-local','hoverBorderColor'=>'--dbs-button-hover-border',
        ];
        foreach($properties as $key=>$property){if($b[$key]!==''){$css[]=$property.':'.$b[$key];}}
        if($b['radius']>=0){$css[]='--dbs-button-radius:'.self::number_text($b['radius']).'px';}
        if($b['paddingX']>0){$css[]='--dbs-button-padding-x:'.self::number_text($b['paddingX']).'px';}
        if($b['paddingY']>0){$css[]='--dbs-button-padding-y:'.self::number_text($b['paddingY']).'px';}
        if($b['weight']>0){$css[]='--dbs-button-weight:'.self::number_text($b['weight']);}
        if($b['letterSpacing']!=0){$css[]='--dbs-button-letter-spacing:'.self::number_text($b['letterSpacing']).'px';}
        if($b['glow']>0){$css[]='--dbs-button-glow:'.self::number_text($b['glow']).'px';}
        $css[]='--dbs-button-transition:'.self::number_text($b['transition']).'ms';
        return ['class'=>implode(' ',$classes),'style'=>self::style($css)];
    }

    public static function button_wrapper_attributes($raw): array {
        return self::button_attributes($raw);
    }

    private static function css_url(string $url): string {
        return strtr($url,[
            '"'=>'%22',"'"=>'%27','('=>'%28',')'=>'%29','\\'=>'%5C',
            "\n"=>'%0A',"\r"=>'%0D',"\t"=>'%09','<'=>'%3C','>'=>'%3E',
        ]);
    }

    private static function style(array $declarations): string {
        return $declarations?implode(';',$declarations).';':'';
    }

    private static function ratio($value): string {
        return self::number_text(((float)$value)/100);
    }

    /** Pick the higher-contrast bounded text tone for author-selected colours. */
    private static function automatic_button_tone(array $button): string {
        return self::automatic_tone(array_values(array_filter([
            (string)($button['color1']??''),(string)($button['color2']??''),
        ],static fn($color)=>$color!=='')));
    }

    /** Select white or deep-ink text using the strongest worst-case contrast. */
    private static function automatic_tone(array $colors): string {
        $backgrounds=[];
        foreach($colors as $color){$rgb=self::rgb((string)$color);if($rgb!==null){$backgrounds[]=$rgb;}}
        if(!$backgrounds){return 'light';}
        $white=[255.0,255.0,255.0];$dark=[23.0,40.0,60.0];
        $white_min=INF;$dark_min=INF;
        foreach($backgrounds as $background){
            $white_min=min($white_min,self::contrast($background,$white));
            $dark_min=min($dark_min,self::contrast($background,$dark));
        }
        return $white_min >= $dark_min ? 'light' : 'dark';
    }

    private static function rgb(string $color): ?array {
        if(!preg_match('/^#([a-f0-9]{3}|[a-f0-9]{6}|[a-f0-9]{8})$/iD',$color,$match)){return null;}
        $hex=$match[1];
        if(strlen($hex)===3){$hex=$hex[0].$hex[0].$hex[1].$hex[1].$hex[2].$hex[2];}
        $alpha=1.0;
        if(strlen($hex)===8){$alpha=hexdec(substr($hex,6,2))/255;$hex=substr($hex,0,6);}
        $rgb=[hexdec(substr($hex,0,2)),hexdec(substr($hex,2,2)),hexdec(substr($hex,4,2))];
        return array_map(static fn($channel)=>(float)$channel*$alpha+255.0*(1-$alpha),$rgb);
    }

    private static function contrast(array $first,array $second): float {
        $luminance=static function(array $rgb): float {
            $channels=array_map(static function($channel): float {$value=((float)$channel)/255;return $value<=0.04045?$value/12.92:pow(($value+0.055)/1.055,2.4);},$rgb);
            return 0.2126*$channels[0]+0.7152*$channels[1]+0.0722*$channels[2];
        };
        $a=$luminance($first);$b=$luminance($second);
        return (max($a,$b)+0.05)/(min($a,$b)+0.05);
    }

    private static function number_text($value): string {
        $text=rtrim(rtrim(number_format((float)$value,4,'.',''),'0'),'.');
        return $text===''||$text==='-0'?'0':$text;
    }
}