resources/src/mediawiki/page/gallery.js

   1 /*!
   2  * Show gallery captions when focused. Copied directly from jquery.mw-jump.js.
   3  * Also Dynamically resize images to justify them.
   4  */
   5 ( function ( mw, $ ) {
   6         var $galleries,
   7                 bound = false,
   8                 // Is there a better way to detect a touchscreen? Current check taken from stack overflow.
   9                 isTouchScreen = !!( window.ontouchstart !== undefined ||
  10                         window.DocumentTouch !== undefined && document instanceof window.DocumentTouch
  11                 );
  12
  13         /**
  14          * Perform the layout justification.
  15          *
  16          * @ignore
  17          * @context {HTMLElement} A `ul.mw-gallery-*` element
  18          */
  19         function justify() {
  20                 var lastTop,
  21                         $img,
  22                         imgWidth,
  23                         imgHeight,
  24                         captionWidth,
  25                         rows = [],
  26                         $gallery = $( this );
  27
  28                 $gallery.children( 'li.gallerybox' ).each( function () {
  29                         // Math.floor to be paranoid if things are off by 0.00000000001
  30                         var top = Math.floor( $( this ).position().top ),
  31                                 $this = $( this );
  32
  33                         if ( top !== lastTop ) {
  34                                 rows[ rows.length ] = [];
  35                                 lastTop = top;
  36                         }
  37
  38                         $img = $this.find( 'div.thumb a.image img' );
  39                         if ( $img.length && $img[ 0 ].height ) {
  40                                 imgHeight = $img[ 0 ].height;
  41                                 imgWidth = $img[ 0 ].width;
  42                         } else {
  43                                 // If we don't have a real image, get the containing divs width/height.
  44                                 // Note that if we do have a real image, using this method will generally
  45                                 // give the same answer, but can be different in the case of a very
  46                                 // narrow image where extra padding is added.
  47                                 imgHeight = $this.children().children( 'div:first' ).height();
  48                                 imgWidth = $this.children().children( 'div:first' ).width();
  49                         }
  50
  51                         // Hack to make an edge case work ok
  52                         if ( imgHeight < 30 ) {
  53                                 // Don't try and resize this item.
  54                                 imgHeight = 0;
  55                         }
  56
  57                         captionWidth = $this.children().children( 'div.gallerytextwrapper' ).width();
  58                         rows[ rows.length - 1 ][ rows[ rows.length - 1 ].length ] = {
  59                                 $elm: $this,
  60                                 width: $this.outerWidth(),
  61                                 imgWidth: imgWidth,
  62                                 // XXX: can divide by 0 ever happen?
  63                                 aspect: imgWidth / imgHeight,
  64                                 captionWidth: captionWidth,
  65                                 height: imgHeight
  66                         };
  67
  68                         // Save all boundaries so we can restore them on window resize
  69                         $this.data( 'imgWidth', imgWidth );
  70                         $this.data( 'imgHeight', imgHeight );
  71                         $this.data( 'width', $this.outerWidth() );
  72                         $this.data( 'captionWidth', captionWidth );
  73                 } );
  74
  75                 ( function () {
  76                         var maxWidth,
  77                                 combinedAspect,
  78                                 combinedPadding,
  79                                 curRow,
  80                                 curRowHeight,
  81                                 wantedWidth,
  82                                 preferredHeight,
  83                                 newWidth,
  84                                 padding,
  85                                 $outerDiv,
  86                                 $innerDiv,
  87                                 $imageDiv,
  88                                 $imageElm,
  89                                 imageElm,
  90                                 $caption,
  91                                 i,
  92                                 j,
  93                                 avgZoom,
  94                                 totalZoom = 0;
  95
  96                         for ( i = 0; i < rows.length; i++ ) {
  97                                 maxWidth = $gallery.width();
  98                                 combinedAspect = 0;
  99                                 combinedPadding = 0;
 100                                 curRow = rows[ i ];
 101                                 curRowHeight = 0;
 102
 103                                 for ( j = 0; j < curRow.length; j++ ) {
 104                                         if ( curRowHeight === 0 ) {
 105                                                 if ( isFinite( curRow[ j ].height ) ) {
 106                                                         // Get the height of this row, by taking the first
 107                                                         // non-out of bounds height
 108                                                         curRowHeight = curRow[ j ].height;
 109                                                 }
 110                                         }
 111
 112                                         if ( curRow[ j ].aspect === 0 || !isFinite( curRow[ j ].aspect ) ) {
 113                                                 // One of the dimensions are 0. Probably should
 114                                                 // not try to resize.
 115                                                 combinedPadding += curRow[ j ].width;
 116                                         } else {
 117                                                 combinedAspect += curRow[ j ].aspect;
 118                                                 combinedPadding += curRow[ j ].width - curRow[ j ].imgWidth;
 119                                         }
 120                                 }
 121
 122                                 // Add some padding for inter-element spacing.
 123                                 combinedPadding += 5 * curRow.length;
 124                                 wantedWidth = maxWidth - combinedPadding;
 125                                 preferredHeight = wantedWidth / combinedAspect;
 126
 127                                 if ( preferredHeight > curRowHeight * 1.5 ) {
 128                                         // Only expand at most 1.5 times current size
 129                                         // As that's as high a resolution as we have.
 130                                         // Also on the off chance there is a bug in this
 131                                         // code, would prevent accidentally expanding to
 132                                         // be 10 billion pixels wide.
 133                                         if ( i === rows.length - 1 ) {
 134                                                 // If its the last row, and we can't fit it,
 135                                                 // don't make the entire row huge.
 136                                                 avgZoom = ( totalZoom / ( rows.length - 1 ) ) * curRowHeight;
 137                                                 if ( isFinite( avgZoom ) && avgZoom >= 1 && avgZoom <= 1.5 ) {
 138                                                         preferredHeight = avgZoom;
 139                                                 } else {
 140                                                         // Probably a single row gallery
 141                                                         preferredHeight = curRowHeight;
 142                                                 }
 143                                         } else {
 144                                                 preferredHeight = 1.5 * curRowHeight;
 145                                         }
 146                                 }
 147                                 if ( !isFinite( preferredHeight ) ) {
 148                                         // This *definitely* should not happen.
 149                                         // Skip this row.
 150                                         continue;
 151                                 }
 152                                 if ( preferredHeight < 5 ) {
 153                                         // Well something clearly went wrong...
 154                                         // Skip this row.
 155                                         continue;
 156                                 }
 157
 158                                 if ( preferredHeight / curRowHeight > 1 ) {
 159                                         totalZoom += preferredHeight / curRowHeight;
 160                                 } else {
 161                                         // If we shrink, still consider that a zoom of 1
 162                                         totalZoom += 1;
 163                                 }
 164
 165                                 for ( j = 0; j < curRow.length; j++ ) {
 166                                         newWidth = preferredHeight * curRow[ j ].aspect;
 167                                         padding = curRow[ j ].width - curRow[ j ].imgWidth;
 168                                         $outerDiv = curRow[ j ].$elm;
 169                                         $innerDiv = $outerDiv.children( 'div' ).first();
 170                                         $imageDiv = $innerDiv.children( 'div.thumb' );
 171                                         $imageElm = $imageDiv.find( 'img' ).first();
 172                                         imageElm = $imageElm.length ? $imageElm[ 0 ] : null;
 173                                         $caption = $outerDiv.find( 'div.gallerytextwrapper' );
 174
 175                                         // Since we are going to re-adjust the height, the vertical
 176                                         // centering margins need to be reset.
 177                                         $imageDiv.children( 'div' ).css( 'margin', '0px auto' );
 178
 179                                         if ( newWidth < 60 || !isFinite( newWidth ) ) {
 180                                                 // Making something skinnier than this will mess up captions,
 181                                                 if ( newWidth < 1 || !isFinite( newWidth ) ) {
 182                                                         $innerDiv.height( preferredHeight );
 183                                                         // Don't even try and touch the image size if it could mean
 184                                                         // making it disappear.
 185                                                         continue;
 186                                                 }
 187                                         } else {
 188                                                 $outerDiv.width( newWidth + padding );
 189                                                 $innerDiv.width( newWidth + padding );
 190                                                 $imageDiv.width( newWidth );
 191                                                 $caption.width( curRow[ j ].captionWidth + ( newWidth - curRow[ j ].imgWidth ) );
 192                                         }
 193
 194                                         if ( imageElm ) {
 195                                                 // We don't always have an img, e.g. in the case of an invalid file.
 196                                                 imageElm.width = newWidth;
 197                                                 imageElm.height = preferredHeight;
 198                                         } else {
 199                                                 // Not a file box.
 200                                                 $imageDiv.height( preferredHeight );
 201                                         }
 202                                 }
 203                         }
 204                 }() );
 205         }
 206
 207         function handleResizeStart() {
 208                 $galleries.children( 'li.gallerybox' ).each( function () {
 209                         var imgWidth = $( this ).data( 'imgWidth' ),
 210                                 imgHeight = $( this ).data( 'imgHeight' ),
 211                                 width = $( this ).data( 'width' ),
 212                                 captionWidth = $( this ).data( 'captionWidth' ),
 213                                 $innerDiv = $( this ).children( 'div' ).first(),
 214                                 $imageDiv = $innerDiv.children( 'div.thumb' ),
 215                                 $imageElm, imageElm;
 216
 217                         // Restore original sizes so we can arrange the elements as on freshly loaded page
 218                         $( this ).width( width );
 219                         $innerDiv.width( width );
 220                         $imageDiv.width( imgWidth );
 221                         $( this ).find( 'div.gallerytextwrapper' ).width( captionWidth );
 222
 223                         $imageElm = $( this ).find( 'img' ).first();
 224                         imageElm = $imageElm.length ? $imageElm[ 0 ] : null;
 225                         if ( imageElm ) {
 226                                 imageElm.width = imgWidth;
 227                                 imageElm.height = imgHeight;
 228                         } else {
 229                                 $imageDiv.height( imgHeight );
 230                         }
 231                 } );
 232         }
 233
 234         function handleResizeEnd() {
 235                 $galleries.each( justify );
 236         }
 237
 238         mw.hook( 'wikipage.content' ).add( function ( $content ) {
 239                 if ( isTouchScreen ) {
 240                         // Always show the caption for a touch screen.
 241                         $content.find( 'ul.mw-gallery-packed-hover' )
 242                                 .addClass( 'mw-gallery-packed-overlay' )
 243                                 .removeClass( 'mw-gallery-packed-hover' );
 244                 } else {
 245                         // Note use of just "a", not a.image, since we want this to trigger if a link in
 246                         // the caption receives focus
 247                         $content.find( 'ul.mw-gallery-packed-hover li.gallerybox' ).on( 'focus blur', 'a', function ( e ) {
 248                                 // Confusingly jQuery leaves e.type as focusout for delegated blur events
 249                                 var gettingFocus = e.type !== 'blur' && e.type !== 'focusout';
 250                                 $( this ).closest( 'li.gallerybox' ).toggleClass( 'mw-gallery-focused', gettingFocus );
 251                         } );
 252                 }
 253
 254                 $galleries = $content.find( 'ul.mw-gallery-packed-overlay, ul.mw-gallery-packed-hover, ul.mw-gallery-packed' );
 255                 // Call the justification asynchronous because live preview fires the hook with detached $content.
 256                 setTimeout( function () {
 257                         $galleries.each( justify );
 258
 259                         // Bind here instead of in the top scope as the callbacks use $galleries.
 260                         if ( !bound ) {
 261                                 bound = true;
 262                                 $( window )
 263                                         .resize( $.debounce( 300, true, handleResizeStart ) )
 264                                         .resize( $.debounce( 300, handleResizeEnd ) );
 265                         }
 266                 } );
 267         } );
 268 }( mediaWiki, jQuery ) );