/*
 *    Copyright [2011] [wisemapping]
 *
 *   Licensed under WiseMapping Public License, Version 1.0 (the "License").
 *   It is basically the Apache License, Version 2.0 (the "License") plus the
 *   "powered by wisemapping" text requirement on every single page;
 *   you may not use this file except in compliance with the License.
 *   You may obtain a copy of the license at
 *
 *       http://www.wisemapping.org/license
 *
 *   Unless required by applicable law or agreed to in writing, software
 *   distributed under the License is distributed on an "AS IS" BASIS,
 *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *   See the License for the specific language governing permissions and
 *   limitations under the License.
 */

mindplot.VariableDistanceBoard = new Class({
        Extends: mindplot.Board,
        initialize: function(defaultHeight, referencePoint) {
            this.parent(defaultHeight, referencePoint);
            var zeroEntryCoordinate = referencePoint.y;
            var entry = this.createBoardEntry(zeroEntryCoordinate - (defaultHeight / 2), zeroEntryCoordinate + (defaultHeight / 2), 0);
            this._entries.set(0, entry);
        },

        lookupEntryByOrder:function(order) {
            var entries = this._entries;
            var index = this._orderToIndex(order);

            var result = entries.get(index);
            if (!$defined(result)) {
                // I've not found a entry. I have to create a new one.
                var i = 1;
                var zeroEntry = entries.get(0);
                var distance = zeroEntry.getWidth() / 2;
                var indexSign = Math.sign(index);
                var absIndex = Math.abs(index);
                while (i < absIndex) {
                    // Move to the next entry ...
                    var entry = entries.get(i, indexSign);
                    if (entry != null) {
                        distance += entry.getWidth();
                    } else {
                        distance += this._defaultWidth;
                    }
                    i++;
                }

                // Calculate limits ...
                var upperLimit = -1;
                var lowerLimit = -1;
                var offset = zeroEntry.workoutEntryYCenter();
                if (index >= 0) {
                    lowerLimit = offset + distance;
                    upperLimit = lowerLimit + this._defaultWidth;
                } else {
                    upperLimit = offset - distance;
                    lowerLimit = upperLimit - this._defaultWidth;
                }

                result = this.createBoardEntry(lowerLimit, upperLimit, order);
            }
            return result;
        },

        createBoardEntry:function(lowerLimit, upperLimit, order) {
            return  new mindplot.BoardEntry(lowerLimit, upperLimit, order);
        },

        updateReferencePoint:function(position) {
            var entries = this._entries;
            var referencePoint = this._referencePoint;

            // Update zero entry current position.
            this._referencePoint = position.clone();
            var yOffset = position.y - referencePoint.y;

            var i = -entries.lowerLength();
            for (; i <= entries.length(1); i++) {
                var entry = entries.get(i);
                if (entry != null) {
                    var upperLimit = entry.getUpperLimit() + yOffset;
                    var lowerLimit = entry.getLowerLimit() + yOffset;
                    entry.setUpperLimit(upperLimit);
                    entry.setLowerLimit(lowerLimit);

                    // Update topic position ...
                    if (!entry.isAvailable()) {
                        var topic = entry.getTopic();
                        var topicPosition = topic.getPosition();
                        topicPosition.y = topicPosition.y + yOffset;

                        // MainTopicToCentral must be positioned based on the referencePoint.
                        var xOffset = position.x - referencePoint.x;
                        topicPosition.x = topicPosition.x + xOffset;

                        topic.setPosition(topicPosition);
                    }
                }
            }
        },

        lookupEntryByPosition:function(pos) {
            core.assert($defined(pos), 'position can not be null');
            var entries = this._entries;
            var zeroEntry = entries.get(0);
            if (zeroEntry.isCoordinateIn(pos.y)) {
                return zeroEntry;
            }

            // Is Upper or lower ?
            var sign = -1;
            if (pos.y >= zeroEntry.getUpperLimit()) {
                sign = 1;
            }

            var i = 1;
            var tempEntry = this.createBoardEntry();
            var currentEntry = zeroEntry;
            while (true) {
                // Move to the next entry ...
                var index = i * sign;
                var entry = entries.get(index);
                if ($defined(entry)) {
                    currentEntry = entry;
                } else {
                    // Calculate boundaries...
                    var lowerLimit, upperLimit;
                    if (sign > 0) {
                        lowerLimit = currentEntry.getUpperLimit();
                        upperLimit = lowerLimit + this._defaultWidth;
                    }
                    else {
                        upperLimit = currentEntry.getLowerLimit();
                        lowerLimit = upperLimit - this._defaultWidth;
                    }

                    // Update current entry.
                    currentEntry = tempEntry;
                    currentEntry.setLowerLimit(lowerLimit);
                    currentEntry.setUpperLimit(upperLimit);

                    var order = this._indexToOrder(index);
                    currentEntry.setOrder(order);
                }

                // Have I found the item?
                if (currentEntry.isCoordinateIn(pos.y)) {
                    break;
                }
                i++;
            }
            return currentEntry;
        },

        update:function(entry) {
            core.assert(entry, 'Entry can not be null');
            var order = entry.getOrder();
            var index = this._orderToIndex(order);

            this._entries.set(index, entry);

        },
        freeEntry:function(entry) {
            var order = entry.getOrder();
            var entries = this._entries;

            var index = this._orderToIndex(order);
            var indexSign = Math.sign(index);

            var currentTopic = entry.getTopic();
            var i = Math.abs(index) + 1;
            while (currentTopic) {
                var e = entries.get(i, indexSign);
                if ($defined(currentTopic) && !$defined(e)) {
                    var entryOrder = this._indexToOrder(i * indexSign);
                    e = this.lookupEntryByOrder(entryOrder);
                }

                // Move the topic to the next entry ...
                var topic = null;
                if ($defined(e)) {
                    topic = e.getTopic();
                    if ($defined(currentTopic)) {
                        e.setTopic(currentTopic);
                    }
                    this.update(e);
                }
                currentTopic = topic;
                i++;
            }

            // Clear the entry topic ...
            entry.setTopic(null);
        },

        _orderToIndex:function(order) {
            var index = Math.round(order / 2);
            return ((order % 2) == 0) ? index : -index;
        },

        _indexToOrder:function(index) {
            var order = Math.abs(index) * 2;
            return (index >= 0) ? order : order - 1;
        },

        inspect:function() {
            return this._entries.inspect();
        }

    });