michael@0: (function() {
michael@0:   "use strict";
michael@0: 
michael@0:   function doFold(cm, pos, options, force) {
michael@0:     var finder = options && (options.call ? options : options.rangeFinder);
michael@0:     if (!finder) finder = CodeMirror.fold.auto;
michael@0:     if (typeof pos == "number") pos = CodeMirror.Pos(pos, 0);
michael@0:     var minSize = options && options.minFoldSize || 0;
michael@0: 
michael@0:     function getRange(allowFolded) {
michael@0:       var range = finder(cm, pos);
michael@0:       if (!range || range.to.line - range.from.line < minSize) return null;
michael@0:       var marks = cm.findMarksAt(range.from);
michael@0:       for (var i = 0; i < marks.length; ++i) {
michael@0:         if (marks[i].__isFold && force !== "fold") {
michael@0:           if (!allowFolded) return null;
michael@0:           range.cleared = true;
michael@0:           marks[i].clear();
michael@0:         }
michael@0:       }
michael@0:       return range;
michael@0:     }
michael@0: 
michael@0:     var range = getRange(true);
michael@0:     if (options && options.scanUp) while (!range && pos.line > cm.firstLine()) {
michael@0:       pos = CodeMirror.Pos(pos.line - 1, 0);
michael@0:       range = getRange(false);
michael@0:     }
michael@0:     if (!range || range.cleared || force === "unfold") return;
michael@0: 
michael@0:     var myWidget = makeWidget(options);
michael@0:     CodeMirror.on(myWidget, "mousedown", function() { myRange.clear(); });
michael@0:     var myRange = cm.markText(range.from, range.to, {
michael@0:       replacedWith: myWidget,
michael@0:       clearOnEnter: true,
michael@0:       __isFold: true
michael@0:     });
michael@0:     myRange.on("clear", function(from, to) {
michael@0:       CodeMirror.signal(cm, "unfold", cm, from, to);
michael@0:     });
michael@0:     CodeMirror.signal(cm, "fold", cm, range.from, range.to);
michael@0:   }
michael@0: 
michael@0:   function makeWidget(options) {
michael@0:     var widget = (options && options.widget) || "\u2194";
michael@0:     if (typeof widget == "string") {
michael@0:       var text = document.createTextNode(widget);
michael@0:       widget = document.createElement("span");
michael@0:       widget.appendChild(text);
michael@0:       widget.className = "CodeMirror-foldmarker";
michael@0:     }
michael@0:     return widget;
michael@0:   }
michael@0: 
michael@0:   // Clumsy backwards-compatible interface
michael@0:   CodeMirror.newFoldFunction = function(rangeFinder, widget) {
michael@0:     return function(cm, pos) { doFold(cm, pos, {rangeFinder: rangeFinder, widget: widget}); };
michael@0:   };
michael@0: 
michael@0:   // New-style interface
michael@0:   CodeMirror.defineExtension("foldCode", function(pos, options, force) {
michael@0:     doFold(this, pos, options, force);
michael@0:   });
michael@0: 
michael@0:   CodeMirror.commands.fold = function(cm) {
michael@0:     cm.foldCode(cm.getCursor());
michael@0:   };
michael@0: 
michael@0:   CodeMirror.registerHelper("fold", "combine", function() {
michael@0:     var funcs = Array.prototype.slice.call(arguments, 0);
michael@0:     return function(cm, start) {
michael@0:       for (var i = 0; i < funcs.length; ++i) {
michael@0:         var found = funcs[i](cm, start);
michael@0:         if (found) return found;
michael@0:       }
michael@0:     };
michael@0:   });
michael@0: 
michael@0:   CodeMirror.registerHelper("fold", "auto", function(cm, start) {
michael@0:     var helpers = cm.getHelpers(start, "fold");
michael@0:     for (var i = 0; i < helpers.length; i++) {
michael@0:       var cur = helpers[i](cm, start);
michael@0:       if (cur) return cur;
michael@0:     }
michael@0:   });
michael@0: })();