/*
 * Bittorrent Client using Qt and libtorrent.
 * Copyright (C) 2019  Thomas Piccirello <thomas.piccirello@gmail.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * In addition, as a special exception, the copyright holders give permission to
 * link this program with the OpenSSL project's "OpenSSL" library (or with
 * modified versions of it that use the same license as the "OpenSSL" library),
 * and distribute the linked executables. You must obey the GNU General Public
 * License in all respects for all of the code used other than "OpenSSL".  If you
 * modify file(s), you may extend this exception to your version of the file(s),
 * but you are not obligated to do so. If you do not wish to do so, delete this
 * exception statement from your version.
 */

'use strict';

if (window.qBittorrent === undefined) {
    window.qBittorrent = {};
}

window.qBittorrent.FileTree = (function() {
    const exports = function() {
        return {
            FilePriority: FilePriority,
            TriState: TriState,
            FileTree: FileTree,
            FileNode: FileNode,
            FolderNode: FolderNode,
        };
    };

    const FilePriority = {
        "Ignored": 0,
        "Normal": 1,
        "High": 6,
        "Maximum": 7,
        "Mixed": -1
    };
    Object.freeze(FilePriority);

    const TriState = {
        "Unchecked": 0,
        "Checked": 1,
        "Partial": 2
    };
    Object.freeze(TriState);

    const FileTree = new Class({
        root: null,
        nodeMap: {},

        setRoot: function(root) {
            this.root = root;
            this.generateNodeMap(root);

            if (this.root.isFolder)
                this.root.calculateSize();
        },

        getRoot: function() {
            return this.root;
        },

        generateNodeMap: function(node) {
            // don't store root node in map
            if (node.root !== null) {
                this.nodeMap[node.rowId] = node;
            }

            node.children.each(function(child) {
                this.generateNodeMap(child);
            }.bind(this));
        },

        getNode: function(rowId) {
            return (this.nodeMap[rowId] === undefined)
                ? null
                : this.nodeMap[rowId];
        },

        getRowId: function(node) {
            return node.rowId;
        },

        /**
         * Returns the nodes in dfs order
         */
        toArray: function() {
            const nodes = [];
            this.root.children.each(function(node) {
                this._getArrayOfNodes(node, nodes);
            }.bind(this));
            return nodes;
        },

        _getArrayOfNodes: function(node, array) {
            array.push(node);
            node.children.each(function(child) {
                this._getArrayOfNodes(child, array);
            }.bind(this));
        }
    });

    const FileNode = new Class({
        name: "",
        rowId: null,
        size: 0,
        checked: TriState.Unchecked,
        remaining: 0,
        progress: 0,
        priority: FilePriority.Normal,
        availability: 0,
        depth: 0,
        root: null,
        data: null,
        isFolder: false,
        children: [],
    });

    const FolderNode = new Class({
        Extends: FileNode,

        initialize: function() {
            this.isFolder = true;
        },

        addChild(node) {
            this.children.push(node);
        },

        /**
         * Recursively calculate size of node and its children
         */
        calculateSize: function() {
            let size = 0;
            let remaining = 0;
            let progress = 0;
            let availability = 0;
            let checked = TriState.Unchecked;
            let priority = FilePriority.Normal;

            let isFirstFile = true;

            this.children.each(function(node) {
                if (node.isFolder)
                    node.calculateSize();

                size += node.size;

                if (isFirstFile) {
                    priority = node.priority;
                    checked = node.checked;
                    isFirstFile = false;
                }
                else {
                    if (priority !== node.priority)
                        priority = FilePriority.Mixed;
                    if (checked !== node.checked)
                        checked = TriState.Partial;
                }

                const isIgnored = (node.priority === FilePriority.Ignored);
                if (!isIgnored) {
                    remaining += node.remaining;
                    progress += (node.progress * node.size);
                    availability += (node.availability * node.size);
                }
            }.bind(this));

            this.size = size;
            this.remaining = remaining;
            this.checked = checked;
            this.progress = (progress / size);
            this.priority = priority;
            this.availability = (availability / size);
        }
    });

    return exports();
})();
