Implement find()

lyfhh56789 · May 30, 2017 · 3041e80 · 3041e80
1 parent 176125e
commit 3041e80
Showing 1 changed file with 72 additions and 9 deletions.
diff --git a/src/section.js b/src/section.js
@@ -113,17 +113,80 @@ class Section {
 		return rendered;
 	}
 
-	/**
-	 * Find a string in a section
-	 * TODO: need reimplementation from v0.2
-	 * @param  {string} query [description]
-	 * @return {[type]} [description]
-	 */
-	find(){
+        /**
+         * Find a string in a section
+         * @param  {string} _query The query string to find
+         * @return {object[]} A list of matches, with form {cfi, excerpt}
+         */
+        find(_query){
+                var section = this;
+                var matches = [];
+                var query = _query.toLowerCase();
+                var find = function(node){
+                        var text = node.textContent.toLowerCase();
+                        var range = section.document.createRange();
+                        var cfi;
+                        var pos;
+                        var last = -1;
+                        var excerpt;
+                        var limit = 150;
 
-	}
+                        while (pos != -1) {
+                                // Search for the query
+                                pos = text.indexOf(query, last + 1);
 
-	/**
+                                if (pos != -1) {
+                                        // We found it! Generate a CFI
+                                        range = section.document.createRange();
+                                        range.setStart(node, pos);
+                                        range.setEnd(node, pos + query.length);
+
+                                        cfi = section.cfiFromRange(range);
+
+                                        // Generate the excerpt
+                                        if (node.textContent.length < limit) {
+                                                excerpt = node.textContent;
+                                        }
+                                        else {
+                                                excerpt = node.textContent.substring(pos - limit/2, pos + limit/2);
+                                                excerpt = "..." + excerpt + "...";
+                                        }
+
+                                        // Add the CFI to the matches list
+                                        matches.push({
+                                                cfi: cfi,
+                                                excerpt: excerpt
+                                        });
+                                }
+
+                                last = pos;
+                        }
+                };
+
+                section.textSprint(section.document, function(node) {
+                        find(node);
+                });
+
+                return matches;
+        };
+
+        textSprint(root, func) {
+                var treeWalker = document.createTreeWalker(root, NodeFilter.SHOW_TEXT, {
+                        acceptNode: function(node) {
+                                if (node.data && ! /^\s*$/.test(node.data)) {
+                                        return NodeFilter.FILTER_ACCEPT;
+                                } else {
+                                        return NodeFilter.FILTER_REJECT;
+                                }
+                        }
+                }, false);
+                var node;
+                while ((node = treeWalker.nextNode())) {
+                        func(node);
+                }
+        };
+
+        /**
 	* Reconciles the current chapters layout properies with
 	* the global layout properities.
 	* @param {object} global  The globa layout settings object, chapter properties string