Split search_index.js into pure JS logic and Liquid data template

assets/js/search_functions.js

@@ -0,0 +1,224 @@
+// Parameters
+var BMAX = 250; // Max blurb size in characters
+var RMAX = 100; // Max number of results to display
+
+function getPositions(result, field) {
+    var positions = [];
+    var md = result.matchData.metadata;
+    for (var searchTerm in md) {
+        var fieldResults = md[searchTerm][field];
+        if (!fieldResults) continue;
+        for (var p in fieldResults.position) sortedInsert(positions, fieldResults.position[p][0]);
+    }
+    return positions;
+}
+
+function resultMatched(result, fromfield) {
+    let md = result.matchData.metadata;
+    for (var st in md) {
+        if (!md[st][fromfield]) continue;
+        for (var mi in md[st][fromfield]['position']) return true;
+    }
+    return false;
+}
+
+function addMatchHighlights(result, blurb, fromfield, startindex, endindex) {
+    var startindex = startindex || 0;
+    var endindex = endindex || blurb.length;
+    var ranges = new Ranges();
+    let md = result.matchData.metadata;
+    var i = 0; var j = 0;
+    for (var searchTerm in md) {
+        if (!md[searchTerm][fromfield]) continue;
+        for (var mi in md[searchTerm][fromfield].position) {
+            let m = md[searchTerm][fromfield].position[mi];
+            i = m[0]; j = i+m[1];
+            if (i < endindex && j > startindex) {
+                ranges.add([(startindex>i?startindex:i)-startindex, j-startindex]);
+            }
+        }
+    }
+    i = ranges.array.length - 1;
+    var ret = blurb;
+    while (i >= 0) {
+        ret = ret.substring(0,ranges.array[i][0]) +
+            '<strong>' + ret.substring(ranges.array[i][0],ranges.array[i][1]) +
+            '</strong>' + ret.substring(ranges.array[i][1], ret.length);
+        i--;
+    }
+    return ret;
+}
+
+function getBlurbForResult(result, item, positions) {
+    var titleMatch = false;
+    let md = result.matchData.metadata;
+    for (var searchTerm in md) {
+        if (md[searchTerm]['title']) {
+            titleMatch = true;
+            break;
+        }
+    }
+    if ((titleMatch || positions.length == 0) && item.description){
+      var ret = item.description;
+      if (item.description.length > BMAX)
+        ret = item.description.substring(0, BMAX) + "...";
+      return addMatchHighlights(result, ret, 'description');
+    }
+    // Calculate the best section of the content to blurb
+    var best_i = -1;
+    var best_n = 0;
+    for (var i in positions) {
+        var n = 1;
+        var j = i+1;
+        while (j < positions.length) {
+            if (positions[j] > positions[i] + BMAX) break;
+            n++; j++;
+        }
+        if (n > best_n) {
+            best_n = n;
+            best_i = i;
+        }
+    }
+    i = positions[best_i];
+    j = positions[best_i + best_n - 1];
+    var m = (i+j)>>1;
+    var startindex = m - (BMAX>>1);
+    var pre = true;
+    if (startindex <= 0){ startindex = 0; pre = false; }
+    var endindex = startindex + BMAX;
+    var ret = item.content.substring(startindex,endindex);
+    ret = addMatchHighlights(result, ret, 'content', startindex, endindex);
+    if (endindex >= item.content.length) return (pre?'...':'') + ret;
+    return (pre?'...':'') + ret + "...";
+}
+
+function categoryName(c) {
+    switch(c) {
+        case 'av': return '<i class="fas fa-volume-up"></i> Recording';
+        case 'articles': return '<i class="far fa-newspaper"></i> Article';
+        case 'booklets': return '<i class="fas fa-book-open"></i> Book';
+        case 'monographs': return '<i class="fas fa-book"></i> Book';
+        case 'papers': return '<i class="far fa-file-powerpoint"></i> Paper';
+        case 'essays': return '<i class="far fa-file-word"></i> Essay';
+        case 'canon': return '<i class="fas fa-dharmachakra"></i> Canonical Work';
+        case 'reference': return '<i class="fas fa-atlas"></i> Reference Work';
+        case 'excerpts': return '<i class="fas fa-book-reader"></i> Excerpt';
+    }
+    return '<i class="far fa-file"></i> Library Item';
+}
+
+function displaySearchResult(result, item) {
+    var positions = getPositions(result, 'content');
+    var blurb = getBlurbForResult(result, item, positions);
+    var type = null;
+    switch (item.type) {
+        case 'courses': type = '<i class="fas fa-chalkboard"></i> Course'; break;
+        case 'content': type = categoryName(item.category); break;
+        case 'posts': type = '<i class="fas fa-rss"></i> Blog Post'; break;
+        case 'journals': type = '<i class="fas fa-newspaper"></i> Journal'; break;
+        case 'authors': type = '<i class="far fa-address-book"></i> Author'; break;
+        case 'publishers': type = '<i class="far fa-building"></i> Publisher'; break;
+        case 'tags': type = '<i class="fas fa-tag"></i> Bibliography'; break;
+        case 'series': type = '<i class="fas fa-list-ol"></i> Series'; break;
+    }
+    var ret = '<li><h3><a href="' + item.url + '">' + addMatchHighlights(result, item.title, 'title') + '</a></h3>';
+    if (type) ret += '<span class="Counter">' + type + '</span>';
+    var lc = 0;
+    for (var i in item.authors) {
+        ret += '<span class="Label ml-1">' +
+            addMatchHighlights(result, item.authors[i], 'author', lc, lc + item.authors[i].length) +
+            '</span>';
+        lc += 2 + item.authors[i].length;
+    }
+    if (resultMatched(result, 'translator')) ret += '<span class="Label ml-1">Translator: ' +
+        addMatchHighlights(result, item.translator, 'translator') +
+        '</span>';
+    if (resultMatched(result, 'tag')) {
+        lc = 0;
+        for (var i in item.tags) {
+            if (!item.tags[i]) continue;
+            let t = '<span class="Label ml-1 text-capitalize"><i class="fas fa-tag"></i> ' +
+                addMatchHighlights(result, item.tags[i].replace('-',' '), 'tag', lc, lc + item.tags[i].length) + '</span>';
+            if (t.includes('<strong>')) ret += t;
+            lc += 1 + item.tags[i].length;
+        }
+    }
+    if (resultMatched(result, 'format')) {
+        lc = 0;
+        for (var i in item.formats) {
+            if (!item.formats[i]) continue;
+            let t = '<span class="Label ml-1"><i class="fas fa-file-arrow-down"></i> ' +
+                addMatchHighlights(result, item.formats[i], 'format', lc, lc + item.formats[i].length) + '</span>';
+            if (t.includes('<strong>')) ret += t;
+            lc += 2 + item.formats[i].length;
+        }
+    }
+    return ret + '<p>' + blurb + '</p></li>';
+}
+
+function displaySearchResults(results) {
+    if (results.length) {
+      var ret = '';
+      for (var i in results) {
+        if (i >= RMAX) break;
+        ret += displaySearchResult(results[i], store[results[i].ref]);
+      }
+      return ret;
+    } else {
+      return '<li>No results found</li>';
+    }
+}
+
+function handleSearchMessage(data, searchFn) {
+  var results = [];
+  var warning = "";
+  var words = data.q.trim().split(" ");
+  for (var i = 0; i < words.length; i++) {
+    const s = words[i].trim();
+    if (!s.startsWith("+") && !s.startsWith("-") && s.length > 1 && lunr.stopWordFilter(s)) {
+      words[i] = "+" + s;
+    } else {
+      words[i] = s;
+    }
+  }
+  var query = words.join(' ').trim();
+  try {
+    results = searchFn(query);
+    if (!results.length){
+      warning = "<li><strong>No results</strong> found matching all of your terms. Results found matching <em>any</em> term:</li>";
+      results = searchFn(data.q.trim());
+    }
+  } catch (err) {
+    if (err.message.indexOf("unrecognised field") >= 0 && query.indexOf(":") >= 0) {
+      results = searchFn(data.q.replaceAll(":"," "));
+    } else { throw err; }
+  }
+  if (!results.length){
+    words = data.q.trim().split(" ");
+    if (words.find(function(w){ return w.length <= 2; }) == undefined) {
+      results = searchFn(words.join("~1 ") + "~1");
+      if (results.length)
+        warning = "<li><strong>No results</strong> found for your query. Perhaps you meant:</li>";
+      else
+        warning = "";
+    } else {
+      warning = "";
+    }
+  }
+  if (data.filterquery && data.filterquery !== "") {
+    var filteredResults = searchFn(data.filterquery);
+    results = results.filter(function(result) {
+      return filteredResults.some(function(filteredResult) {
+        return filteredResult.ref === result.ref;
+      });
+    });
+  }
+  return {
+    "warninghtml": warning,
+    "html": displaySearchResults(results),
+    "count": results ? results.length : 0,
+    "q": data.q,
+    "filterquery": data.filterquery,
+    "qt": data.qt
+  };
+}