/**
 * $Id: Selection.js 906 2008-08-24 16:47:29Z spocke $
 *
 * @author Moxiecode
 * @copyright Copyright © 2004-2008, Moxiecode Systems AB, All rights reserved.
 */

(function() {
	function trimNl(s) {
		return s.replace(/[\n\r]+/g, '');
	};

	// Shorten names
	var is = tinymce.is, isIE = tinymce.isIE, each = tinymce.each;

	/**#@+
	 * @class This class handles text and control selection it's an crossbrowser utility class.
	 * Consult the TinyMCE Wiki API for more details and examples on how to use this class.
	 * @member tinymce.dom.Selection
	 */
	tinymce.create('tinymce.dom.Selection', {
		/**
		 * Constructs a new selection instance.
		 *
		 * @constructor
		 * @param {tinymce.dom.DOMUtils} dom DOMUtils object reference.
		 * @param {Window} win Window to bind the selection object to.
		 * @param {tinymce.dom.Serializer} serializer DOM serialization class to use for getContent.
		 */
		Selection : function(dom, win, serializer) {
			var t = this;

			t.dom = dom;
			t.win = win;
			t.serializer = serializer;

			// Add events
			each([
				'onBeforeSetContent',
				'onBeforeGetContent',
				'onSetContent',
				'onGetContent'
			], function(e) {
				t[e] = new tinymce.util.Dispatcher(t);
			});

			// Prevent leaks
			tinymce.addUnload(t.destroy, t);
		},

		/**#@+
		 * @method
		 */

		/**
		 * Returns the selected contents using the DOM serializer passed in to this class.
		 *
		 * @param {Object} s Optional settings class with for example output format text or html.
		 * @return {String} Selected contents in for example HTML format.
		 */
		getContent : function(s) {
			var t = this, r = t.getRng(), e = t.dom.create("body"), se = t.getSel(), wb, wa, n;

			s = s || {};
			wb = wa = '';
			s.get = true;
			s.format = s.format || 'html';
			t.onBeforeGetContent.dispatch(t, s);

			if (s.format == 'text')
				return t.isCollapsed() ? '' : (r.text || (se.toString ? se.toString() : ''));

			if (r.cloneContents) {
				n = r.cloneContents();

				if (n)
					e.appendChild(n);
			} else if (is(r.item) || is(r.htmlText))
				e.innerHTML = r.item ? r.item(0).outerHTML : r.htmlText;
			else
				e.innerHTML = r.toString();

			// Keep whitespace before and after
			if (/^\s/.test(e.innerHTML))
				wb = ' ';

			if (/\s+$/.test(e.innerHTML))
				wa = ' ';

			s.getInner = true;

			s.content = t.isCollapsed() ? '' : wb + t.serializer.serialize(e, s) + wa;
			t.onGetContent.dispatch(t, s);

			return s.content;
		},

		/**
		 * Sets the current selection to the specified content. If any contents is selected it will be replaced
		 * with the contents passed in to this function. If there is no selection the contents will be inserted
		 * where the caret is placed in the editor/page.
		 *
		 * @param {String} h HTML contents to set could also be other formats depending on settings.
		 * @param {Object} s Optional settings object with for example data format.
		 */
		setContent : function(h, s) {
			var t = this, r = t.getRng(), c, d = t.win.document;

			s = s || {format : 'html'};
			s.set = true;
			h = s.content = t.dom.processHTML(h);

			// Dispatch before set content event
			t.onBeforeSetContent.dispatch(t, s);
			h = s.content;

			if (r.insertNode) {
				// Make caret marker since insertNode places the caret in the beginning of text after insert
				h += '<span id="__caret">_</span>';

				// Delete and insert new node
				r.deleteContents();
				r.insertNode(t.getRng().createContextualFragment(h));

				// Move to caret marker
				c = t.dom.get('__caret');

				// Make sure we wrap it compleatly, Opera fails with a simple select call
				r = d.createRange();
				r.setStartBefore(c);
				r.setEndAfter(c);
				t.setRng(r);

				// Delete the marker, and hopefully the caret gets placed in the right location
				d.execCommand('Delete', false, null);

				// In case it's still there
				t.dom.remove('__caret');
			} else {
				if (r.item) {
					// Delete content and get caret text selection
					d.execCommand('Delete', false, null);
					r = t.getRng();
				}

				r.pasteHTML(h);
			}

			// Dispatch set content event
			t.onSetContent.dispatch(t, s);
		},

		/**
		 * Returns the start element of a selection range. If the start is in a text
		 * node the parent element will be returned.
		 *
		 * @return {Element} Start element of selection range.
		 */
		getStart : function() {
			var t = this, r = t.getRng(), e;

			if (isIE) {
				if (r.item)
					return r.item(0);

				r = r.duplicate();
				r.collapse(1);
				e = r.parentElement();

				if (e && e.nodeName == 'BODY')
					return e.firstChild;

				return e;
			} else {
				e = r.startContainer;

				if (e.nodeName == 'BODY')
					return e.firstChild;

				return t.dom.getParent(e, function(n) {return n.nodeType == 1;});
			}
		},

		/**
		 * Returns the end element of a selection range. If the end is in a text
		 * node the parent element will be returned.
		 *
		 * @return {Element} End element of selection range.
		 */
		getEnd : function() {
			var t = this, r = t.getRng(), e;

			if (isIE) {
				if (r.item)
					return r.item(0);

				r = r.duplicate();
				r.collapse(0);
				e = r.parentElement();

				if (e && e.nodeName == 'BODY')
					return e.lastChild;

				return e;
			} else {
				e = r.endContainer;

				if (e.nodeName == 'BODY')
					return e.lastChild;

				return t.dom.getParent(e, function(n) {return n.nodeType == 1;});
			}
		},

		/**
		 * Returns a bookmark location for the current selection. This bookmark object
		 * can then be used to restore the selection after some content modification to the document.
		 *
		 * @param {bool} si Optional state if the bookmark should be simple or not. Default is complex.
		 * @return {Object} Bookmark object, use moveToBookmark with this object to restore the selection.
		 */
		getBookmark : function(si) {
			var t = this, r = t.getRng(), tr, sx, sy, vp = t.dom.getViewPort(t.win), e, sp, bp, le, c = -0xFFFFFF, s, ro = t.dom.getRoot(), wb = 0, wa = 0, nv;
			sx = vp.x;
			sy = vp.y;

			// Simple bookmark fast but not as persistent
			if (si == 'simple')
				return {rng : r, scrollX : sx, scrollY : sy};

			// Handle IE
			if (isIE) {
				// Control selection
				if (r.item) {
					e = r.item(0);

					each(t.dom.select(e.nodeName), function(n, i) {
						if (e == n) {
							sp = i;
							return false;
						}
					});

					return {
						tag : e.nodeName,
						index : sp,
						scrollX : sx,
						scrollY : sy
					};
				}

				// Text selection
				tr = t.dom.doc.body.createTextRange();
				tr.moveToElementText(ro);
				tr.collapse(true);
				bp = Math.abs(tr.move('character', c));

				tr = r.duplicate();
				tr.collapse(true);
				sp = Math.abs(tr.move('character', c));

				tr = r.duplicate();
				tr.collapse(false);
				le = Math.abs(tr.move('character', c)) - sp;

				return {
					start : sp - bp,
					length : le,
					scrollX : sx,
					scrollY : sy
				};
			}

			// Handle W3C
			e = t.getNode();
			s = t.getSel();

			if (!s)
				return null;

			// Image selection
			if (e && e.nodeName == 'IMG') {
				return {
					scrollX : sx,
					scrollY : sy
				};
			}

			// Text selection

			function getPos(r, sn, en) {
				var w = t.dom.doc.createTreeWalker(r, NodeFilter.SHOW_TEXT, null, false), n, p = 0, d = {};

				while ((n = w.nextNode()) != null) {
					if (n == sn)
						d.start = p;

					if (n == en) {
						d.end = p;
						return d;
					}

					p += trimNl(n.nodeValue || '').length;
				}

				return null;
			};

			// Caret or selection
			if (s.anchorNode == s.focusNode && s.anchorOffset == s.focusOffset) {
				e = getPos(ro, s.anchorNode, s.focusNode);

				if (!e)
					return {scrollX : sx, scrollY : sy};

				// Count whitespace before
				trimNl(s.anchorNode.nodeValue || '').replace(/^\s+/, function(a) {wb = a.length;});

				return {
					start : Math.max(e.start + s.anchorOffset - wb, 0),
					end : Math.max(e.end + s.focusOffset - wb, 0),
					scrollX : sx,
					scrollY : sy,
					beg : s.anchorOffset - wb == 0
				};
			} else {
				e = getPos(ro, r.startContainer, r.endContainer);

				// Count whitespace before start and end container
				//(r.startContainer.nodeValue || '').replace(/^\s+/, function(a) {wb = a.length;});
				//(r.endContainer.nodeValue || '').replace(/^\s+/, function(a) {wa = a.length;});

				if (!e)
					return {scrollX : sx, scrollY : sy};

				return {
					start : Math.max(e.start + r.startOffset - wb, 0),
					end : Math.max(e.end + r.endOffset - wa, 0),
					scrollX : sx,
					scrollY : sy,
					beg : r.startOffset - wb == 0
				};
			}
		},

		/**
		 * Restores the selection to the specified bookmark.
		 *
		 * @param {Object} bookmark Bookmark to restore selection from.
		 * @return {bool} true/false if it was successful or not.
		 */
		moveToBookmark : function(b) {
			var t = this, r = t.getRng(), s = t.getSel(), ro = t.dom.getRoot(), sd, nvl, nv;

			function getPos(r, sp, ep) {
				var w = t.dom.doc.createTreeWalker(r, NodeFilter.SHOW_TEXT, null, false), n, p = 0, d = {}, o, v, wa, wb;

				while ((n = w.nextNode()) != null) {
					wa = wb = 0;

					nv = n.nodeValue || '';
					//nv.replace(/^\s+[^\s]/, function(a) {wb = a.length - 1;});
					//nv.replace(/[^\s]\s+$/, function(a) {wa = a.length - 1;});

					nvl = trimNl(nv).length;
					p += nvl;

					if (p >= sp && !d.startNode) {
						o = sp - (p - nvl);

						// Fix for odd quirk in FF
						if (b.beg && o >= nvl)
							continue;

						d.startNode = n;
						d.startOffset = o + wb;
					}

					if (p >= ep) {
						d.endNode = n;
						d.endOffset = ep - (p - nvl) + wb;
						return d;
					}
				}

				return null;
			};

			if (!b)
				return false;

			t.win.scrollTo(b.scrollX, b.scrollY);

			// Handle explorer
			if (isIE) {
				// Handle simple
				if (r = b.rng) {
					try {
						r.select();
					} catch (ex) {
						// Ignore
					}

					return true;
				}

				t.win.focus();

				// Handle control bookmark
				if (b.tag) {
					r = ro.createControlRange();

					each(t.dom.select(b.tag), function(n, i) {
						if (i == b.index)
							r.addElement(n);
					});
				} else {
					// Try/catch needed since this operation breaks when TinyMCE is placed in hidden divs/tabs
					try {
						// Incorrect bookmark
						if (b.start < 0)
							return true;

						r = s.createRange();
						r.moveToElementText(ro);
						r.collapse(true);
						r.moveStart('character', b.start);
						r.moveEnd('character', b.length);
					} catch (ex2) {
						return true;
					}
				}

				try {
					r.select();
				} catch (ex) {
					// Needed for some odd IE bug #1843306
				}

				return true;
			}

			// Handle W3C
			if (!s)
				return false;

			// Handle simple
			if (b.rng) {
				s.removeAllRanges();
				s.addRange(b.rng);
			} else {
				if (is(b.start) && is(b.end)) {
					try {
						sd = getPos(ro, b.start, b.end);

						if (sd) {
							r = t.dom.doc.createRange();
							r.setStart(sd.startNode, sd.startOffset);
							r.setEnd(sd.endNode, sd.endOffset);
							s.removeAllRanges();
							s.addRange(r);
						}

						if (!tinymce.isOpera)
							t.win.focus();
					} catch (ex) {
						// Ignore
					}
				}
			}
		},

		/**
		 * Selects the specified element. This will place the start and end of the selection range around the element.
		 *
		 * @param {Element} n HMTL DOM element to select.
		 * @param {} c Bool state if the contents should be selected or not on non IE browser.
		 * @return {Element} Selected element the same element as the one that got passed in.
		 */
		select : function(n, c) {
			var t = this, r = t.getRng(), s = t.getSel(), b, fn, ln, d = t.win.document;

			function first(n) {
				return n ? d.createTreeWalker(n, NodeFilter.SHOW_TEXT, null, false).nextNode() : null;
			};

			function last(n) {
				var c, o, w;

				if (!n)
					return null;

				w = d.createTreeWalker(n, NodeFilter.SHOW_TEXT, null, false);
				while (c = w.nextNode())
					o = c;

				return o;
			};

			if (isIE) {
				try {
					b = d.body;

					if (/^(IMG|TABLE)$/.test(n.nodeName)) {
						r = b.createControlRange();
						r.addElement(n);
					} else {
						r = b.createTextRange();
						r.moveToElementText(n);
					}

					r.select();
				} catch (ex) {
					// Throws illigal agrument in IE some times
				}
			} else {
				if (c) {
					fn = first(n);
					ln = last(n);

					if (fn && ln) {
						//console.debug(fn, ln);
						r = d.createRange();
						r.setStart(fn, 0);
						r.setEnd(ln, ln.nodeValue.length);
					} else
						r.selectNode(n);
				} else
					r.selectNode(n);

				t.setRng(r);
			}

			return n;
		},

		/**
		 * Returns true/false if the selection range is collapsed or not. Collapsed means if it's a caret or a larger selection.
		 *
		 * @return {bool} true/false state if the selection range is collapsed or not. Collapsed means if it's a caret or a larger selection.
		 */
		isCollapsed : function() {
			var t = this, r = t.getRng(), s = t.getSel();

			if (!r || r.item)
				return false;

			return !s || r.boundingWidth == 0 || r.collapsed;
		},

		/**
		 * Collapse the selection to start or end of range.
		 *
		 * @param {bool} b Optional boolean state if to collapse to end or not. Defaults to start.
		 */
		collapse : function(b) {
			var t = this, r = t.getRng(), n;

			// Control range on IE
			if (r.item) {
				n = r.item(0);
				r = this.win.document.body.createTextRange();
				r.moveToElementText(n);
			}

			r.collapse(!!b);
			t.setRng(r);
		},

		/**
		 * Returns the browsers internal selection object.
		 *
		 * @return {Selection} Internal browser selection object.
		 */
		getSel : function() {
			var t = this, w = this.win;

			return w.getSelection ? w.getSelection() : w.document.selection;
		},

		/**
		 * Returns the browsers internal range object.
		 *
		 * @return {Range} Internal browser range object.
		 */
		getRng : function() {
			var t = this, s = t.getSel(), r;

			try {
				if (s)
					r = s.rangeCount > 0 ? s.getRangeAt(0) : (s.createRange ? s.createRange() : t.win.document.createRange());
			} catch (ex) {
				// IE throws unspecified error here if TinyMCE is placed in a frame/iframe
			}

			// No range found then create an empty one
			// This can occur when the editor is placed in a hidden container element on Gecko
			// Or on IE when there was an exception
			if (!r)
				r = isIE ? t.win.document.body.createTextRange() : t.win.document.createRange();

			return r;
		},

		/**
		 * Changes the selection to the specified DOM range.
		 *
		 * @param {Range} r Range to select.
		 */
		setRng : function(r) {
			var s;

			if (!isIE) {
				s = this.getSel();

				if (s) {
					s.removeAllRanges();
					s.addRange(r);
				}
			} else {
				try {
					r.select();
				} catch (ex) {
					// Needed for some odd IE bug #1843306
				}
			}
		},

		/**
		 * Sets the current selection to the specified DOM element.
		 *
		 * @param {Element} n Element to set as the contents of the selection.
		 * @return {Element} Returns the element that got passed in.
		 */
		setNode : function(n) {
			var t = this;

			t.setContent(t.dom.getOuterHTML(n));

			return n;
		},

		/**
		 * Returns the currently selected element or the common ancestor element for both start and end of the selection.
		 *
		 * @return {Element} Currently selected element or common ancestor element.
		 */
		getNode : function() {
			var t = this, r = t.getRng(), s = t.getSel(), e;

			if (!isIE) {
				// Range maybe lost after the editor is made visible again
				if (!r)
					return t.dom.getRoot();

				e = r.commonAncestorContainer;

				// Handle selection a image or other control like element such as anchors
				if (!r.collapsed) {
					// If the anchor node is a element instead of a text node then return this element
					if (tinymce.isWebKit && s.anchorNode && s.anchorNode.nodeType == 1) 
						return s.anchorNode.childNodes[s.anchorOffset]; 

					if (r.startContainer == r.endContainer) {
						if (r.startOffset - r.endOffset < 2) {
							if (r.startContainer.hasChildNodes())
								e = r.startContainer.childNodes[r.startOffset];
						}
					}
				}

				return t.dom.getParent(e, function(n) {
					return n.nodeType == 1;
				});
			}

			return r.item ? r.item(0) : r.parentElement();
		},

		destroy : function(s) {
			var t = this;

			t.win = null;

			// Manual destroy then remove unload handler
			if (!s)
				tinymce.removeUnload(t.destroy);
		}

		/**#@-*/
	});
})();
