/**
 * TableDnD plug-in for JQuery, allows you to drag and drop table rows
 * You can set up various options to control how the system will work
 * Copyright (c) Denis Howlett <denish@isocra.com>
 * Licensed like jQuery, see http://docs.jquery.com/License.
 *
 * Configuration options:
 *
 * onDragStyle
 *     This is the style that is assigned to the row during drag. There are limitations to the styles that can be
 *     associated with a row (such as you can't assign a border--well you can, but it won't be
 *     displayed). (So instead consider using onDragClass.) The CSS style to apply is specified as
 *     a map (as used in the jQuery css(...) function).
 * onDropStyle
 *     This is the style that is assigned to the row when it is dropped. As for onDragStyle, there are limitations
 *     to what you can do. Also this replaces the original style, so again consider using onDragClass which
 *     is simply added and then removed on drop.
 * onDragClass
 *     This class is added for the duration of the drag and then removed when the row is dropped. It is more
 *     flexible than using onDragStyle since it can be inherited by the row cells and other content. The default
 *     is class is tDnD_whileDrag. So to use the default, simply customise this CSS class in your
 *     stylesheet.
 * onDrop
 *     Pass a function that will be called when the row is dropped. The function takes 2 parameters: the table
 *     and the row that was dropped. You can work out the new order of the rows by using
 *     table.rows.
 * onDragStart
 *     Pass a function that will be called when the user starts dragging. The function takes 2 parameters: the
 *     table and the row which the user has started to drag.
 * onDragStop
 *     Pass a function that will be called when the user stops dragging regardless of if the rows have been
 *     rearranged. The function takes 2 parameters: the table and the row which the user was dragging.
 * onAllowDrop
 *     Pass a function that will be called as a row is over another row. If the function returns true, allow
 *     dropping on that row, otherwise not. The function takes 2 parameters: the dragged row and the row under
 *     the cursor. It returns a boolean: true allows the drop, false doesn't allow it.
 * scrollAmount
 *     This is the number of pixels to scroll if the user moves the mouse cursor to the top or bottom of the
 *     window. The page should automatically scroll up or down as appropriate (tested in IE6, IE7, Safari, FF2,
 *     FF3 beta
 * dragHandle
 *     This is a jQuery mach string for one or more cells in each row that is draggable. If you
 *     specify this, then you are responsible for setting cursor: move in the CSS and only these cells
 *     will have the drag behaviour. If you do not specify a dragHandle, then you get the old behaviour where
 *     the whole row is draggable.
 *
 * Other ways to control behaviour:
 *
 * Add class="nodrop" to any rows for which you don't want to allow dropping, and class="nodrag" to any rows
 * that you don't want to be draggable.
 *
 * Inside the onDrop method you can also call $.tableDnD.serialize() this returns a string of the form
 * <tableID>[]=<rowID1>&<tableID>[]=<rowID2> so that you can send this back to the server. The table must have
 * an ID as must all the rows.
 *
 * Other methods:
 *
 * $("...").tableDnDUpdate()
 * Will update all the matching tables, that is it will reapply the mousedown method to the rows (or handle cells).
 * This is useful if you have updated the table rows using Ajax and you want to make the table draggable again.
 * The table maintains the original configuration (so you don't have to specify it again).
 *
 * $("...").tableDnDSerialize()
 * Will serialize and return the serialized string as above, but for each of the matching tables--so it can be
 * called from anywhere and isn't dependent on the currentTable being set up correctly before calling
 *
 * Known problems:
 * - Auto-scoll has some problems with IE7  (it scrolls even when it shouldn't), work-around: set scrollAmount to 0
 *
 * Version 0.2: 2008-02-20 First public version
 * Version 0.3: 2008-02-07 Added onDragStart option
 *                         Made the scroll amount configurable (default is 5 as before)
 * Version 0.4: 2008-03-15 Changed the noDrag/noDrop attributes to nodrag/nodrop classes
 *                         Added onAllowDrop to control dropping
 *                         Fixed a bug which meant that you couldn't set the scroll amount in both directions
 *                         Added serialize method
 * Version 0.5: 2008-05-16 Changed so that if you specify a dragHandle class it doesn't make the whole row
 *                         draggable
 *                         Improved the serialize method to use a default (and settable) regular expression.
 *                         Added tableDnDupate() and tableDnDSerialize() to be called when you are outside the table
 * Version 0.6: 2011-12-02 Added support for touch devices
 * Version 0.7  2012-04-09 Now works with jQuery 1.7 and supports touch, tidied up tabs and spaces
 */
!function ($, window, document, undefined) {
// Determine if this is a touch device
var hasTouch   = 'ontouchstart' in document.documentElement,
    startEvent = 'touchstart mousedown',
    moveEvent  = 'touchmove mousemove',
    endEvent   = 'touchend mouseup';

$(document).ready(function () {
    function parseStyle(css) {
        var objMap = {},
            parts = css.match(/([^;:]+)/g) || [];
        while (parts.length)
            objMap[parts.shift()] = parts.shift().trim();

        return objMap;
    }
    $('table').each(function () {
        if ($(this).data('table') == 'dnd') {

            $(this).tableDnD({
                onDragStyle: $(this).data('ondragstyle') && parseStyle($(this).data('ondragstyle')) || null,
                onDropStyle: $(this).data('ondropstyle') && parseStyle($(this).data('ondropstyle')) || null,
                onDragClass: $(this).data('ondragclass') == undefined && "tDnD_whileDrag" || $(this).data('ondragclass'),
                onDrop: $(this).data('ondrop') && new Function('table', 'row', $(this).data('ondrop')), // 'return eval("'+$(this).data('ondrop')+'");') || null,
                onDragStart: $(this).data('ondragstart') && new Function('table', 'row' ,$(this).data('ondragstart')), // 'return eval("'+$(this).data('ondragstart')+'");') || null,
                onDragStop: $(this).data('ondragstop') && new Function('table', 'row' ,$(this).data('ondragstop')),
                scrollAmount: $(this).data('scrollamount') || 5,
                sensitivity: $(this).data('sensitivity') || 10,
                hierarchyLevel: $(this).data('hierarchylevel') || 0,
                indentArtifact: $(this).data('indentartifact') || '<div class="indent">&nbsp;</div>',
                autoWidthAdjust: $(this).data('autowidthadjust') || true,
                autoCleanRelations: $(this).data('autocleanrelations') || true,
                jsonPretifySeparator: $(this).data('jsonpretifyseparator') || '\t',
                serializeRegexp: $(this).data('serializeregexp') && new RegExp($(this).data('serializeregexp')) || /[^\-]*$/,
                serializeParamName: $(this).data('serializeparamname') || false,
                dragHandle: $(this).data('draghandle') || null
            });
        }


    });
});

jQuery.tableDnD = {
    /** Keep hold of the current table being dragged */
    currentTable: null,
    /** Keep hold of the current drag object if any */
    dragObject: null,
    /** The current mouse offset */
    mouseOffset: null,
    /** Remember the old value of X and Y so that we don't do too much processing */
    oldX: 0,
    oldY: 0,

    /** Actually build the structure */
    build: function(options) {
        // Set up the defaults if any

        this.each(function() {
            // This is bound to each matching table, set up the defaults and override with user options
            this.tableDnDConfig = $.extend({
                onDragStyle: null,
                onDropStyle: null,
                // Add in the default class for whileDragging
                onDragClass: "tDnD_whileDrag",
                onDrop: null,
                onDragStart: null,
                onDragStop: null,
                scrollAmount: 5,
                /** Sensitivity setting will throttle the trigger rate for movement detection */
                sensitivity: 10,
                /** Hierarchy level to support parent child. 0 switches this functionality off */
                hierarchyLevel: 0,
                /** The html artifact to prepend the first cell with as indentation */
                indentArtifact: '<div class="indent">&nbsp;</div>',
                /** Automatically adjust width of first cell */
                autoWidthAdjust: true,
                /** Automatic clean-up to ensure relationship integrity */
                autoCleanRelations: true,
                /** Specify a number (4) as number of spaces or any indent string for JSON.stringify */
                jsonPretifySeparator: '\t',
                /** The regular expression to use to trim row IDs */
                serializeRegexp: /[^\-]*$/,
                /** If you want to specify another parameter name instead of the table ID */
                serializeParamName: false,
                /** If you give the name of a class here, then only Cells with this class will be draggable */
                dragHandle: null
            }, options || {});

            // Now make the rows draggable
            $.tableDnD.makeDraggable(this);
            // Prepare hierarchy support
            this.tableDnDConfig.hierarchyLevel
                && $.tableDnD.makeIndented(this);
        });

        // Don't break the chain
        return this;
    },
    makeIndented: function (table) {
        var config = table.tableDnDConfig,
            rows = table.rows,
            firstCell = $(rows).first().find('td:first')[0],
            indentLevel = 0,
            cellWidth = 0,
            longestCell,
            tableStyle;

        if ($(table).hasClass('indtd'))
            return null;

        tableStyle = $(table).addClass('indtd').attr('style');
        $(table).css({whiteSpace: "nowrap"});

        for (var w = 0; w < rows.length; w++) {
            if (cellWidth < $(rows[w]).find('td:first').text().length) {
                cellWidth = $(rows[w]).find('td:first').text().length;
                longestCell = w;
            }
        }
        $(firstCell).css({width: 'auto'});
        for (w = 0; w < config.hierarchyLevel; w++)
            $(rows[longestCell]).find('td:first').prepend(config.indentArtifact);
        firstCell && $(firstCell).css({width: firstCell.offsetWidth});
        tableStyle && $(table).css(tableStyle);

        for (w = 0; w < config.hierarchyLevel; w++)
            $(rows[longestCell]).find('td:first').children(':first').remove();

        config.hierarchyLevel
            && $(rows).each(function () {
                indentLevel = $(this).data('level') || 0;
                indentLevel <= config.hierarchyLevel
                    && $(this).data('level', indentLevel)
                    || $(this).data('level', 0);
                for (var i = 0; i < $(this).data('level'); i++)
                    $(this).find('td:first').prepend(config.indentArtifact);
            });

        return this;
    },
    /** This function makes all the rows on the table draggable apart from those marked as "NoDrag" */
    makeDraggable: function(table) {
        var config = table.tableDnDConfig;

        config.dragHandle
            // We only need to add the event to the specified cells
            && $(config.dragHandle, table).each(function() {
                // The cell is bound to "this"
                $(this).bind(startEvent, function(e) {
                    $.tableDnD.initialiseDrag($(this).parents('tr')[0], table, this, e, config);
                    return false;
                });
            })
            // For backwards compatibility, we add the event to the whole row
            // get all the rows as a wrapped set
            || $(table.rows).each(function() {
                // Iterate through each row, the row is bound to "this"
                if (! $(this).hasClass("nodrag")) {
                    $(this).bind(startEvent, function(e) {
                        if (e.target.tagName == "TD") {
                            $.tableDnD.initialiseDrag(this, table, this, e, config);
                            return false;
                        }
                    }).css("cursor", "move"); // Store the tableDnD object
                } else {
                    $(this).css("cursor", ""); // Remove the cursor if we don't have the nodrag class
                }
            });
    },
    currentOrder: function() {
        var rows = this.currentTable.rows;
        return $.map(rows, function (val) {
            return ($(val).data('level') + val.id).replace(/\s/g, '');
        }).join('');
    },
    initialiseDrag: function(dragObject, table, target, e, config) {
        this.dragObject    = dragObject;
        this.currentTable  = table;
        this.mouseOffset   = this.getMouseOffset(target, e);
        this.originalOrder = this.currentOrder();

        // Now we need to capture the mouse up and mouse move event
        // We can use bind so that we don't interfere with other event handlers
        $(document)
            .bind(moveEvent, this.mousemove)
            .bind(endEvent, this.mouseup);

        // Call the onDragStart method if there is one
        config.onDragStart
            && config.onDragStart(table, target);
    },
    updateTables: function() {
        this.each(function() {
            // this is now bound to each matching table
            if (this.tableDnDConfig)
                $.tableDnD.makeDraggable(this);
        });
    },
    /** Get the mouse coordinates from the event (allowing for browser differences) */
    mouseCoords: function(e) {
        if (e.originalEvent.changedTouches)
            return {
                x: e.originalEvent.changedTouches[0].clientX,
                y: e.originalEvent.changedTouches[0].clientY
            };

        if(e.pageX || e.pageY)
            return {
                x: e.pageX,
                y: e.pageY
            };

        return {
            x: e.clientX + document.body.scrollLeft - document.body.clientLeft,
            y: e.clientY + document.body.scrollTop  - document.body.clientTop
        };
    },
    /** Given a target element and a mouse eent, get the mouse offset from that element.
     To do this we need the element's position and the mouse position */
    getMouseOffset: function(target, e) {
        var mousePos,
            docPos;

        e = e || window.event;

        docPos    = this.getPosition(target);
        mousePos  = this.mouseCoords(e);

        return {
            x: mousePos.x - docPos.x,
            y: mousePos.y - docPos.y
        };
    },
    /** Get the position of an element by going up the DOM tree and adding up all the offsets */
    getPosition: function(element) {
        var left = 0,
            top  = 0;

        // Safari fix -- thanks to Luis Chato for this!
        // Safari 2 doesn't correctly grab the offsetTop of a table row
        // this is detailed here:
        // http://jacob.peargrove.com/blog/2006/technical/table-row-offsettop-bug-in-safari/
        // the solution is likewise noted there, grab the offset of a table cell in the row - the firstChild.
        // note that firefox will return a text node as a first child, so designing a more thorough
        // solution may need to take that into account, for now this seems to work in firefox, safari, ie
        if (element.offsetHeight == 0)
            element = element.firstChild; // a table cell

        while (element.offsetParent) {
            left   += element.offsetLeft;
            top    += element.offsetTop;
            element = element.offsetParent;
        }

        left += element.offsetLeft;
        top  += element.offsetTop;

        return {
            x: left,
            y: top
        };
    },
    autoScroll: function (mousePos) {
      var config       = this.currentTable.tableDnDConfig,
          yOffset      = window.pageYOffset,
          windowHeight = window.innerHeight
            ? window.innerHeight
            : document.documentElement.clientHeight
            ? document.documentElement.clientHeight
            : document.body.clientHeight;

        // Windows version
        // yOffset=document.body.scrollTop;
        if (document.all)
            if (typeof document.compatMode != 'undefined'
                && document.compatMode != 'BackCompat')
                yOffset = document.documentElement.scrollTop;
            else if (typeof document.body != 'undefined')
                yOffset = document.body.scrollTop;

        mousePos.y - yOffset < config.scrollAmount
            && window.scrollBy(0, - config.scrollAmount)
        || windowHeight - (mousePos.y - yOffset) < config.scrollAmount
            && window.scrollBy(0, config.scrollAmount);

    },
    moveVerticle: function (moving, currentRow) {

        if (0 != moving.vertical
            // If we're over a row then move the dragged row to there so that the user sees the
            // effect dynamically
            && currentRow
            && this.dragObject != currentRow
            && this.dragObject.parentNode == currentRow.parentNode)
            0 > moving.vertical
                && this.dragObject.parentNode.insertBefore(this.dragObject, currentRow.nextSibling)
            || 0 < moving.vertical
                && this.dragObject.parentNode.insertBefore(this.dragObject, currentRow);

    },
    moveHorizontal: function (moving, currentRow) {
        var config       = this.currentTable.tableDnDConfig,
            currentLevel;

        if (!config.hierarchyLevel
            || 0 == moving.horizontal
            // We only care if moving left or right on the current row
            || !currentRow
            || this.dragObject != currentRow)
                return null;

            currentLevel = $(currentRow).data('level');

            0 < moving.horizontal
                && currentLevel > 0
                && $(currentRow).find('td:first').children(':first').remove()
                && $(currentRow).data('level', --currentLevel);

            0 > moving.horizontal
                && currentLevel < config.hierarchyLevel
                && $(currentRow).prev().data('level') >= currentLevel
                && $(currentRow).children(':first').prepend(config.indentArtifact)
                && $(currentRow).data('level', ++currentLevel);

    },
    mousemove: function(e) {
        var dragObj      = $($.tableDnD.dragObject),
            config       = $.tableDnD.currentTable.tableDnDConfig,
            currentRow,
            mousePos,
            moving,
            x,
            y;

        e && e.preventDefault();

        if (!$.tableDnD.dragObject)
            return false;

        // prevent touch device screen scrolling
        e.type == 'touchmove'
            && event.preventDefault(); // TODO verify this is event and not really e

        // update the style to show we're dragging
        config.onDragClass
            && dragObj.addClass(config.onDragClass)
            || dragObj.css(config.onDragStyle);

        mousePos = $.tableDnD.mouseCoords(e);
        x = mousePos.x - $.tableDnD.mouseOffset.x;
        y = mousePos.y - $.tableDnD.mouseOffset.y;

        // auto scroll the window
        $.tableDnD.autoScroll(mousePos);

        currentRow = $.tableDnD.findDropTargetRow(dragObj, y);
        moving = $.tableDnD.findDragDirection(x, y);

        $.tableDnD.moveVerticle(moving, currentRow);
        $.tableDnD.moveHorizontal(moving, currentRow);

        return false;
    },
    findDragDirection: function (x,y) {
        var sensitivity = this.currentTable.tableDnDConfig.sensitivity,
            oldX        = this.oldX,
            oldY        = this.oldY,
            xMin        = oldX - sensitivity,
            xMax        = oldX + sensitivity,
            yMin        = oldY - sensitivity,
            yMax        = oldY + sensitivity,
            moving      = {
                horizontal: x >= xMin && x <= xMax ? 0 : x > oldX ? -1 : 1,
                vertical  : y >= yMin && y <= yMax ? 0 : y > oldY ? -1 : 1
            };

        // update the old value
        if (moving.horizontal != 0)
            this.oldX    = x;
        if (moving.vertical   != 0)
            this.oldY    = y;

        return moving;
    },
    /** We're only worried about the y position really, because we can only move rows up and down */
    findDropTargetRow: function(draggedRow, y) {
        var rowHeight = 0,
            rows      = this.currentTable.rows,
            config    = this.currentTable.tableDnDConfig,
            rowY      = 0,
            row       = null;

        for (var i = 0; i < rows.length; i++) {
            row       = rows[i];
            rowY      = this.getPosition(row).y;
            rowHeight = parseInt(row.offsetHeight) / 2;
            if (row.offsetHeight == 0) {
                rowY      = this.getPosition(row.firstChild).y;
                rowHeight = parseInt(row.firstChild.offsetHeight) / 2;
            }
            // Because we always have to insert before, we need to offset the height a bit
            if (y > (rowY - rowHeight) && y < (rowY + rowHeight))
                // that's the row we're over
                // If it's the same as the current row, ignore it
                if (draggedRow.is(row)
                    || (config.onAllowDrop
                    && !config.onAllowDrop(draggedRow, row))
                    // If a row has nodrop class, then don't allow dropping (inspired by John Tarr and Famic)
                    || $(row).hasClass("nodrop"))
                        return null;
                else
                    return row;
        }
        return null;
    },
    processMouseup: function() {
        if (!this.currentTable || !this.dragObject)
            return null;

        var config      = this.currentTable.tableDnDConfig,
            droppedRow  = this.dragObject,
            parentLevel = 0,
            myLevel     = 0;

        // Unbind the event handlers
        $(document)
            .unbind(moveEvent, this.mousemove)
            .unbind(endEvent,  this.mouseup);

        config.hierarchyLevel
            && config.autoCleanRelations
            && $(this.currentTable.rows).first().find('td:first').children().each(function () {
                myLevel = $(this).parents('tr:first').data('level');
                myLevel
                    && $(this).parents('tr:first').data('level', --myLevel)
                    && $(this).remove();
            })
            && config.hierarchyLevel > 1
            && $(this.currentTable.rows).each(function () {
                myLevel = $(this).data('level');
                if (myLevel > 1) {
                    parentLevel = $(this).prev().data('level');
                    while (myLevel > parentLevel + 1) {
                        $(this).find('td:first').children(':first').remove();
                        $(this).data('level', --myLevel);
                    }
                }
            });

        // If we have a dragObject, then we need to release it,
        // The row will already have been moved to the right place so we just reset stuff
        config.onDragClass
            && $(droppedRow).removeClass(config.onDragClass)
            || $(droppedRow).css(config.onDropStyle);

        this.dragObject = null;
        // Call the onDrop method if there is one
        config.onDrop
            && this.originalOrder != this.currentOrder()
            && $(droppedRow).hide().fadeIn('fast')
            && config.onDrop(this.currentTable, droppedRow);

        // Call the onDragStop method if there is one
        config.onDragStop
            && config.onDragStop(this.currentTable, droppedRow);

        this.currentTable = null; // let go of the table too
    },
    mouseup: function(e) {
        e && e.preventDefault();
        $.tableDnD.processMouseup();
        return false;
    },
    jsonize: function(pretify) {
        var table = this.currentTable;
        if (pretify)
            return JSON.stringify(
                this.tableData(table),
                null,
                table.tableDnDConfig.jsonPretifySeparator
            );
        return JSON.stringify(this.tableData(table));
    },
    serialize: function() {
        return $.param(this.tableData(this.currentTable));
    },
    serializeTable: function(table) {
        var result = "";
        var paramName = table.tableDnDConfig.serializeParamName || table.id;
        var rows = table.rows;
        for (var i=0; i<rows.length; i++) {
            if (result.length > 0) result += "&";
            var rowId = rows[i].id;
            if (rowId && table.tableDnDConfig && table.tableDnDConfig.serializeRegexp) {
                rowId = rowId.match(table.tableDnDConfig.serializeRegexp)[0];
                result += paramName + '[]=' + rowId;
            }
        }
        return result;
    },
    serializeTables: function() {
        var result = [];
        $('table').each(function() {
            this.id && result.push($.param($.tableDnD.tableData(this)));
        });
        return result.join('&');
    },
    tableData: function (table) {
        var config = table.tableDnDConfig,
            previousIDs  = [],
            currentLevel = 0,
            indentLevel  = 0,
            rowID        = null,
            data         = {},
            getSerializeRegexp,
            paramName,
            currentID,
            rows;

        if (!table)
            table = this.currentTable;
        if (!table || !table.rows || !table.rows.length)
            return {error: { code: 500, message: "Not a valid table."}};
        if (!table.id && !config.serializeParamName)
            return {error: { code: 500, message: "No serializable unique id provided."}};
        
        rows      = config.autoCleanRelations
                        && table.rows
                        || $.makeArray(table.rows);
        paramName = config.serializeParamName || table.id;
        currentID = paramName;

        getSerializeRegexp = function (rowId) {
            if (rowId && config && config.serializeRegexp)
                return rowId.match(config.serializeRegexp)[0];
            return rowId;
        };

        data[currentID] = [];
        !config.autoCleanRelations
            && $(rows[0]).data('level')
            && rows.unshift({id: 'undefined'});



        for (var i=0; i < rows.length; i++) {
            if (config.hierarchyLevel) {
                indentLevel = $(rows[i]).data('level') || 0;
                if (indentLevel == 0) {
                    currentID   = paramName;
                    previousIDs = [];
                }
                else if (indentLevel > currentLevel) {
                    previousIDs.push([currentID, currentLevel]);
                    currentID = getSerializeRegexp(rows[i-1].id);
                }
                else if (indentLevel < currentLevel) {
                    for (var h = 0; h < previousIDs.length; h++) {
                        if (previousIDs[h][1] == indentLevel)
                            currentID         = previousIDs[h][0];
                        if (previousIDs[h][1] >= currentLevel)
                            previousIDs[h][1] = 0;
                    }
                }
                currentLevel = indentLevel;

                if (!$.isArray(data[currentID]))
                    data[currentID] = [];
                rowID = getSerializeRegexp(rows[i].id);
                rowID && data[currentID].push(rowID);
            }
            else {
                rowID = getSerializeRegexp(rows[i].id);
                rowID && data[currentID].push(rowID);
            }
        }
        return data;
    }
};

jQuery.fn.extend(
    {
        tableDnD             : $.tableDnD.build,
        tableDnDUpdate       : $.tableDnD.updateTables,
        tableDnDSerialize    : $.proxy($.tableDnD.serialize, $.tableDnD),
        tableDnDSerializeAll : $.tableDnD.serializeTables,
        tableDnDData         : $.proxy($.tableDnD.tableData, $.tableDnD)
    }
);

}(jQuery, window, window.document);
