[enh] oscar: image thumbnail layout

Adjust thumbnail sizes to fill the container width

searx/static/themes/__common__/js/image_layout.js

@@ -0,0 +1,163 @@
+/**
+*
+* Google Image Layout v0.0.1
+* Description, by Anh Trinh.
+* Heavily modified for searx
+* https://ptgamr.github.io/2014-09-12-google-image-layout/
+* https://ptgamr.github.io/google-image-layout/src/google-image-layout.js
+*
+* @license Free to use under the MIT License.
+*
+*/
+
+(function (w, d) {
+  function ImageLayout(container_selector, results_selector, img_selector, margin, maxHeight) {
+    this.container_selector = container_selector;
+    this.results_selector = results_selector;
+    this.img_selector = img_selector;
+    this.margin = margin;
+    this.maxHeight = maxHeight;
+    this.isAlignDone = true;
+  }
+
+  /**
+  * Get the height that make all images fit the container
+  *
+  * width = w1 + w2 + w3 + ... = r1*h + r2*h + r3*h + ...
+  *
+  * @param  {[type]} images the images to be calculated
+  * @param  {[type]} width  the container witdth
+  * @param  {[type]} margin the margin between each image
+  *
+  * @return {[type]}        the height
+  */
+  ImageLayout.prototype._getHeigth = function (images, width) {
+    var i, img;
+    var r = 0;
+
+    for (i = 0; i < images.length; i++) {
+      img = images[i];
+      if ((img.naturalWidth > 0) && (img.naturalHeight > 0)) {
+        r += img.naturalWidth / img.naturalHeight;
+      } else {
+        // assume that not loaded images are square
+        r += 1;
+      }
+    }
+
+    return (width - images.length * this.margin) / r; //have to round down because Firefox will automatically roundup value with number of decimals > 3
+  };
+
+  ImageLayout.prototype._setSize = function (images, height) {
+    var i, img, imgWidth;
+    var imagesLength = images.length, resultNode;
+
+    for (i = 0; i < imagesLength; i++) {
+      img = images[i];
+      if ((img.naturalWidth > 0) && (img.naturalHeight > 0)) {
+        imgWidth = height * img.naturalWidth / img.naturalHeight;
+      } else {
+        // not loaded image : make it square as _getHeigth said it
+        imgWidth = height;
+      }
+      img.style.width = imgWidth + 'px';
+      img.style.height = height + 'px';
+      img.style.marginLeft = '3px';
+      img.style.marginTop = '3px';
+      img.style.marginRight = this.margin - 7 + 'px'; // -4 is the negative margin of the inline element
+      img.style.marginBottom = this.margin - 7 + 'px';
+      resultNode = img.parentNode.parentNode;
+      if (!resultNode.classList.contains('js')) {
+        resultNode.classList.add('js');
+      }
+    }
+  };
+
+  ImageLayout.prototype._alignImgs = function (imgGroup) {
+    var isSearching, slice, i, h;
+    var containerElement = d.querySelector(this.container_selector);
+    var containerCompStyles = window.getComputedStyle(containerElement);
+    var containerPaddingLeft = parseInt(containerCompStyles.getPropertyValue('padding-left'), 10);
+    var containerPaddingRight = parseInt(containerCompStyles.getPropertyValue('padding-right'), 10);
+    var containerWidth = containerElement.clientWidth - containerPaddingLeft - containerPaddingRight;
+
+    while (imgGroup.length > 0) {
+      isSearching = true;
+      for (i = 1; i <= imgGroup.length && isSearching; i++) {
+        slice = imgGroup.slice(0, i);
+        h = this._getHeigth(slice, containerWidth);
+        if (h < this.maxHeight) {
+          this._setSize(slice, h);
+          // continue with the remaining images
+          imgGroup = imgGroup.slice(i);
+          isSearching = false;
+        }
+      }
+      if (isSearching) {
+        this._setSize(slice, Math.min(this.maxHeight, h));
+        break;
+      }
+    }
+  };
+
+  ImageLayout.prototype.align = function () {
+    var i;
+    var results_selectorNode = d.querySelectorAll(this.results_selector);
+    var results_length = results_selectorNode.length;
+    var previous = null;
+    var current = null;
+    var imgGroup = [];
+
+    for (i = 0; i < results_length; i++) {
+      current = results_selectorNode[i];
+      if (current.previousElementSibling !== previous && imgGroup.length > 0) {
+        // the current image is not connected to previous one
+        // so the current image is the start of a new group of images.
+        // so call _alignImgs to align the current group
+        this._alignImgs(imgGroup);
+        // and start a new empty group of images
+        imgGroup = [];
+      }
+      // add the current image to the group (only the img tag)
+      imgGroup.push(current.querySelector(this.img_selector));
+      // update the previous variable
+      previous = current;
+    }
+    // align the remaining images
+    if (imgGroup.length > 0) {
+      this._alignImgs(imgGroup);
+    }
+  };
+
+  ImageLayout.prototype.watch = function () {
+    var i, img;
+    var obj = this;
+    var results_nodes = d.querySelectorAll(this.results_selector);
+    var results_length = results_nodes.length;
+
+    function throttleAlign() {
+      if (obj.isAlignDone) {
+        obj.isAlignDone = false;
+        setTimeout(function () {
+          obj.align();
+          obj.isAlignDone = true;
+        }, 100);
+      }
+    }
+
+    w.addEventListener('pageshow', throttleAlign);
+    w.addEventListener('load', throttleAlign);
+    w.addEventListener('resize', throttleAlign);
+
+    for (i = 0; i < results_length; i++) {
+      img = results_nodes[i].querySelector(this.img_selector);
+      if (img !== null && img !== undefined) {
+        img.addEventListener('load', throttleAlign);
+        img.addEventListener('error', throttleAlign);
+      }
+    }
+  };
+
+  w.searx.ImageLayout = ImageLayout;
+
+}(window, document));