<?php

namespace CpChart\Chart;

/**
 *  pSpring - class to draw spring graphs
 *
 *  Version     : 2.1.4
 *  Made by     : Jean-Damien POGOLOTTI
 *  Last Update : 19/01/2014
 *
 *  This file can be distributed under the license you can find at :
 *
 *  http://www.pchart.net/license
 *
 *  You can find the whole class documentation on the pChart web site.
 */
class Spring
{
    /**
     * @var array
     */
    public $History = array();

    /**
     * @var array
     */
    public $Data = array();

    /**
     * @var array
     */
    public $Default = array();

    /**
     * @var array
     */
    public $Labels = array();

    /**
     * @var array
     */
    public $Links = array();

    /**
     * @var type
     */
    public $pChartObject;

    /**
     * @var int
     */
    public $X1;

    /**
     * @var int
     */
    public $Y1;

    /**
     * @var int
     */
    public $X2;

    /**
     * @var int
     */
    public $Y2;

    /**
     * @var boolean
     */
    public $AutoComputeFreeZone = false;

    public function __construct()
    {
        /* Set nodes defaults */
        $this->Default["R"] = 255;
        $this->Default["G"] = 255;
        $this->Default["B"] = 255;
        $this->Default["Alpha"] = 100;
        $this->Default["BorderR"] = 0;
        $this->Default["BorderG"] = 0;
        $this->Default["BorderB"] = 0;
        $this->Default["BorderAlpha"] = 100;
        $this->Default["Surrounding"] = null;
        $this->Default["BackgroundR"] = 255;
        $this->Default["BackgroundG"] = 255;
        $this->Default["BackgroundB"] = 255;
        $this->Default["BackgroundAlpha"] = 0;
        $this->Default["Force"] = 1;
        $this->Default["NodeType"] = NODE_TYPE_FREE;
        $this->Default["Size"] = 5;
        $this->Default["Shape"] = NODE_SHAPE_CIRCLE;
        $this->Default["FreeZone"] = 40;
        $this->Default["LinkR"] = 0;
        $this->Default["LinkG"] = 0;
        $this->Default["LinkB"] = 0;
        $this->Default["LinkAlpha"] = 0;

        $this->Labels["Type"] = LABEL_CLASSIC;
        $this->Labels["R"] = 0;
        $this->Labels["G"] = 0;
        $this->Labels["B"] = 0;
        $this->Labels["Alpha"] = 100;
    }

    /**
     * Set default links options
     * @param array $Settings
     */
    public function setLinkDefaults(array $Settings = array())
    {
        if (isset($Settings["R"])) {
            $this->Default["LinkR"] = $Settings["R"];
        }
        if (isset($Settings["G"])) {
            $this->Default["LinkG"] = $Settings["G"];
        }
        if (isset($Settings["B"])) {
            $this->Default["LinkB"] = $Settings["B"];
        }
        if (isset($Settings["Alpha"])) {
            $this->Default["LinkAlpha"] = $Settings["Alpha"];
        }
    }

    /**
     * Set default links options
     * @param array $Settings
     */
    public function setLabelsSettings(array $Settings = array())
    {
        if (isset($Settings["Type"])) {
            $this->Labels["Type"] = $Settings["Type"];
        }
        if (isset($Settings["R"])) {
            $this->Labels["R"] = $Settings["R"];
        }
        if (isset($Settings["G"])) {
            $this->Labels["G"] = $Settings["G"];
        }
        if (isset($Settings["B"])) {
            $this->Labels["B"] = $Settings["B"];
        }
        if (isset($Settings["Alpha"])) {
            $this->Labels["Alpha"] = $Settings["Alpha"];
        }
    }

    /**
     * Auto compute the FreeZone size based on the number of connections
     */
    public function autoFreeZone()
    {
        /* Check connections reciprocity */
        foreach ($this->Data as $Key => $Settings) {
            if (isset($Settings["Connections"])) {
                $this->Data[$Key]["FreeZone"] = count($Settings["Connections"]) * 10 + 20;
            } else {
                $this->Data[$Key]["FreeZone"] = 20;
            }
        }
    }

    /**
     * Set link properties
     * @param int $FromNode
     * @param int $ToNode
     * @param array $Settings
     * @return null|int
     */
    public function linkProperties($FromNode, $ToNode, array $Settings)
    {
        if (!isset($this->Data[$FromNode])) {
            return 0;
        }
        if (!isset($this->Data[$ToNode])) {
            return 0;
        }

        $R = isset($Settings["R"]) ? $Settings["R"] : 0;
        $G = isset($Settings["G"]) ? $Settings["G"] : 0;
        $B = isset($Settings["B"]) ? $Settings["B"] : 0;
        $Alpha = isset($Settings["Alpha"]) ? $Settings["Alpha"] : 100;
        $Name = isset($Settings["Name"]) ? $Settings["Name"] : null;
        $Ticks = isset($Settings["Ticks"]) ? $Settings["Ticks"] : null;

        $this->Links[$FromNode][$ToNode]["R"] = $R;
        $this->Links[$ToNode][$FromNode]["R"] = $R;
        $this->Links[$FromNode][$ToNode]["G"] = $G;
        $this->Links[$ToNode][$FromNode]["G"] = $G;
        $this->Links[$FromNode][$ToNode]["B"] = $B;
        $this->Links[$ToNode][$FromNode]["B"] = $B;
        $this->Links[$FromNode][$ToNode]["Alpha"] = $Alpha;
        $this->Links[$ToNode][$FromNode]["Alpha"] = $Alpha;
        $this->Links[$FromNode][$ToNode]["Name"] = $Name;
        $this->Links[$ToNode][$FromNode]["Name"] = $Name;
        $this->Links[$FromNode][$ToNode]["Ticks"] = $Ticks;
        $this->Links[$ToNode][$FromNode]["Ticks"] = $Ticks;
    }

    /**
     * @param array $Settings
     */
    public function setNodeDefaults(array $Settings = array())
    {
        if (isset($Settings["R"])) {
            $this->Default["R"] = $Settings["R"];
        }
        if (isset($Settings["G"])) {
            $this->Default["G"] = $Settings["G"];
        }
        if (isset($Settings["B"])) {
            $this->Default["B"] = $Settings["B"];
        }
        if (isset($Settings["Alpha"])) {
            $this->Default["Alpha"] = $Settings["Alpha"];
        }
        if (isset($Settings["BorderR"])) {
            $this->Default["BorderR"] = $Settings["BorderR"];
        }
        if (isset($Settings["BorderG"])) {
            $this->Default["BorderG"] = $Settings["BorderG"];
        }
        if (isset($Settings["BorderB"])) {
            $this->Default["BorderB"] = $Settings["BorderB"];
        }
        if (isset($Settings["BorderAlpha"])) {
            $this->Default["BorderAlpha"] = $Settings["BorderAlpha"];
        }
        if (isset($Settings["Surrounding"])) {
            $this->Default["Surrounding"] = $Settings["Surrounding"];
        }
        if (isset($Settings["BackgroundR"])) {
            $this->Default["BackgroundR"] = $Settings["BackgroundR"];
        }
        if (isset($Settings["BackgroundG"])) {
            $this->Default["BackgroundG"] = $Settings["BackgroundG"];
        }
        if (isset($Settings["BackgroundB"])) {
            $this->Default["BackgroundB"] = $Settings["BackgroundB"];
        }
        if (isset($Settings["BackgroundAlpha"])) {
            $this->Default["BackgroundAlpha"] = $Settings["BackgroundAlpha"];
        }
        if (isset($Settings["NodeType"])) {
            $this->Default["NodeType"] = $Settings["NodeType"];
        }
        if (isset($Settings["Size"])) {
            $this->Default["Size"] = $Settings["Size"];
        }
        if (isset($Settings["Shape"])) {
            $this->Default["Shape"] = $Settings["Shape"];
        }
        if (isset($Settings["FreeZone"])) {
            $this->Default["FreeZone"] = $Settings["FreeZone"];
        }
    }

    /**
     * Add a node
     * @param int $NodeID
     * @param array $Settings
     * @return null|int
     */
    public function addNode($NodeID, array $Settings = array())
    {
        /* if the node already exists, ignore */
        if (isset($this->Data[$NodeID])) {
            return 0;
        }

        $Name = isset($Settings["Name"]) ? $Settings["Name"] : "Node " . $NodeID;
        $Connections = isset($Settings["Connections"]) ? $Settings["Connections"] : null;

        $R = isset($Settings["R"]) ? $Settings["R"] : $this->Default["R"];
        $G = isset($Settings["G"]) ? $Settings["G"] : $this->Default["G"];
        $B = isset($Settings["B"]) ? $Settings["B"] : $this->Default["B"];
        $Alpha = isset($Settings["Alpha"]) ? $Settings["Alpha"] : $this->Default["Alpha"];
        $BorderR = isset($Settings["BorderR"]) ? $Settings["BorderR"] : $this->Default["BorderR"];
        $BorderG = isset($Settings["BorderG"]) ? $Settings["BorderG"] : $this->Default["BorderG"];
        $BorderB = isset($Settings["BorderB"]) ? $Settings["BorderB"] : $this->Default["BorderB"];
        $BorderAlpha = isset($Settings["BorderAlpha"]) ? $Settings["BorderAlpha"] : $this->Default["BorderAlpha"];
        $Surrounding = isset($Settings["Surrounding"]) ? $Settings["Surrounding"] : $this->Default["Surrounding"];
        $BackgroundR = isset($Settings["BackgroundR"]) ? $Settings["BackgroundR"] : $this->Default["BackgroundR"];
        $BackgroundG = isset($Settings["BackgroundG"]) ? $Settings["BackgroundG"] : $this->Default["BackgroundG"];
        $BackgroundB = isset($Settings["BackgroundB"]) ? $Settings["BackgroundB"] : $this->Default["BackgroundB"];
        $BackgroundAlpha = isset($Settings["BackgroundAlpha"])
            ? $Settings["BackgroundAlpha"] : $this->Default["BackgroundAlpha"]
        ;
        $Force = isset($Settings["Force"]) ? $Settings["Force"] : $this->Default["Force"];
        $NodeType = isset($Settings["NodeType"]) ? $Settings["NodeType"] : $this->Default["NodeType"];
        $Size = isset($Settings["Size"]) ? $Settings["Size"] : $this->Default["Size"];
        $Shape = isset($Settings["Shape"]) ? $Settings["Shape"] : $this->Default["Shape"];
        $FreeZone = isset($Settings["FreeZone"]) ? $Settings["FreeZone"] : $this->Default["FreeZone"];

        if ($Surrounding != null) {
            $BorderR = $R + $Surrounding;
            $BorderG = $G + $Surrounding;
            $BorderB = $B + $Surrounding;
        }

        $this->Data[$NodeID]["R"] = $R;
        $this->Data[$NodeID]["G"] = $G;
        $this->Data[$NodeID]["B"] = $B;
        $this->Data[$NodeID]["Alpha"] = $Alpha;
        $this->Data[$NodeID]["BorderR"] = $BorderR;
        $this->Data[$NodeID]["BorderG"] = $BorderG;
        $this->Data[$NodeID]["BorderB"] = $BorderB;
        $this->Data[$NodeID]["BorderAlpha"] = $BorderAlpha;
        $this->Data[$NodeID]["BackgroundR"] = $BackgroundR;
        $this->Data[$NodeID]["BackgroundG"] = $BackgroundG;
        $this->Data[$NodeID]["BackgroundB"] = $BackgroundB;
        $this->Data[$NodeID]["BackgroundAlpha"] = $BackgroundAlpha;
        $this->Data[$NodeID]["Name"] = $Name;
        $this->Data[$NodeID]["Force"] = $Force;
        $this->Data[$NodeID]["Type"] = $NodeType;
        $this->Data[$NodeID]["Size"] = $Size;
        $this->Data[$NodeID]["Shape"] = $Shape;
        $this->Data[$NodeID]["FreeZone"] = $FreeZone;
        if ($Connections != null) {
            if (is_array($Connections)) {
                foreach ($Connections as $Key => $Value) {
                    $this->Data[$NodeID]["Connections"][] = $Value;
                }
            } else {
                $this->Data[$NodeID]["Connections"][] = $Connections;
            }
        }
    }

    /**
     * Set color attribute for a list of nodes
     * @param array|string $Nodes
     * @param array $Settings
     */
    public function setNodesColor($Nodes, array $Settings = array())
    {
        if (is_array($Nodes)) {
            foreach ($Nodes as $Key => $NodeID) {
                if (isset($this->Data[$NodeID])) {
                    if (isset($Settings["R"])) {
                        $this->Data[$NodeID]["R"] = $Settings["R"];
                    }
                    if (isset($Settings["G"])) {
                        $this->Data[$NodeID]["G"] = $Settings["G"];
                    }
                    if (isset($Settings["B"])) {
                        $this->Data[$NodeID]["B"] = $Settings["B"];
                    }
                    if (isset($Settings["Alpha"])) {
                        $this->Data[$NodeID]["Alpha"] = $Settings["Alpha"];
                    }
                    if (isset($Settings["BorderR"])) {
                        $this->Data[$NodeID]["BorderR"] = $Settings["BorderR"];
                    }
                    if (isset($Settings["BorderG"])) {
                        $this->Data[$NodeID]["BorderG"] = $Settings["BorderG"];
                    }
                    if (isset($Settings["BorderB"])) {
                        $this->Data[$NodeID]["BorderB"] = $Settings["BorderB"];
                    }
                    if (isset($Settings["BorderAlpha"])) {
                        $this->Data[$NodeID]["BorderAlpha"] = $Settings["BorderAlpha"];
                    }
                    if (isset($Settings["Surrounding"])) {
                        $this->Data[$NodeID]["BorderR"] = $this->Data[$NodeID]["R"] + $Settings["Surrounding"];
                        $this->Data[$NodeID]["BorderG"] = $this->Data[$NodeID]["G"] + $Settings["Surrounding"];
                        $this->Data[$NodeID]["BorderB"] = $this->Data[$NodeID]["B"] + $Settings["Surrounding"];
                    }
                }
            }
        } else {
            if (isset($Settings["R"])) {
                $this->Data[$Nodes]["R"] = $Settings["R"];
            }
            if (isset($Settings["G"])) {
                $this->Data[$Nodes]["G"] = $Settings["G"];
            }
            if (isset($Settings["B"])) {
                $this->Data[$Nodes]["B"] = $Settings["B"];
            }
            if (isset($Settings["Alpha"])) {
                $this->Data[$Nodes]["Alpha"] = $Settings["Alpha"];
            }
            if (isset($Settings["BorderR"])) {
                $this->Data[$Nodes]["BorderR"] = $Settings["BorderR"];
            }
            if (isset($Settings["BorderG"])) {
                $this->Data[$Nodes]["BorderG"] = $Settings["BorderG"];
            }
            if (isset($Settings["BorderB"])) {
                $this->Data[$Nodes]["BorderB"] = $Settings["BorderB"];
            }
            if (isset($Settings["BorderAlpha"])) {
                $this->Data[$Nodes]["BorderAlpha"] = $Settings["BorderAlpha"];
            }
            if (isset($Settings["Surrounding"])) {
                $this->Data[$Nodes]["BorderR"] = $this->Data[$NodeID]["R"] + $Settings["Surrounding"];
                $this->Data[$NodeID]["BorderG"] = $this->Data[$NodeID]["G"] + $Settings["Surrounding"];
                $this->Data[$NodeID]["BorderB"] = $this->Data[$NodeID]["B"] + $Settings["Surrounding"];
            }
        }
    }

    /**
     * Returns all the nodes details
     * @return array
     */
    public function dumpNodes()
    {
        return $this->Data;
    }

    /**
     * Check if a connection exists and create it if required
     * @param string|int $SourceID
     * @param string|int $TargetID
     * @return boolean|null
     */
    public function checkConnection($SourceID, $TargetID)
    {
        if (isset($this->Data[$SourceID]["Connections"])) {
            foreach ($this->Data[$SourceID]["Connections"] as $ConnectionID) {
                if ($TargetID == $ConnectionID) {
                    return true;
                }
            }
        }
        $this->Data[$SourceID]["Connections"][] = $TargetID;
    }

    /**
     * Get the median linked nodes position
     * @param string $Key
     * @param int $X
     * @param int $Y
     * @return array
     */
    public function getMedianOffset($Key, $X, $Y)
    {
        $Cpt = 1;
        if (isset($this->Data[$Key]["Connections"])) {
            foreach ($this->Data[$Key]["Connections"] as $NodeID) {
                if (isset($this->Data[$NodeID]["X"])
                    && isset($this->Data[$NodeID]["Y"])
                ) {
                    $X = $X + $this->Data[$NodeID]["X"];
                    $Y = $Y + $this->Data[$NodeID]["Y"];
                    $Cpt++;
                }
            }
        }
        return array("X" => $X / $Cpt, "Y" => $Y / $Cpt);
    }

    /**
     * Return the ID of the attached partner with the biggest weight
     * @param string $Key
     * @return string
     */
    public function getBiggestPartner($Key)
    {
        if (!isset($this->Data[$Key]["Connections"])) {
            return "";
        }

        $MaxWeight = 0;
        $Result = "";
        foreach ($this->Data[$Key]["Connections"] as $Key => $PeerID) {
            if ($this->Data[$PeerID]["Weight"] > $MaxWeight) {
                $MaxWeight = $this->Data[$PeerID]["Weight"];
                $Result = $PeerID;
            }
        }
        return $Result;
    }

    /**
     * Do the initial node positions computing pass
     * @param int $Algorithm
     */
    public function firstPass($Algorithm)
    {
        $CenterX = ($this->X2 - $this->X1) / 2 + $this->X1;
        $CenterY = ($this->Y2 - $this->Y1) / 2 + $this->Y1;

        /* Check connections reciprocity */
        foreach ($this->Data as $Key => $Settings) {
            if (isset($Settings["Connections"])) {
                foreach ($Settings["Connections"] as $ID => $ConnectionID) {
                    $this->checkConnection($ConnectionID, $Key);
                }
            }
        }

        if ($this->AutoComputeFreeZone) {
            $this->autoFreeZone();
        }

        /* Get the max number of connections */
        $MaxConnections = 0;
        foreach ($this->Data as $Key => $Settings) {
            if (isset($Settings["Connections"])) {
                if ($MaxConnections < count($Settings["Connections"])) {
                    $MaxConnections = count($Settings["Connections"]);
                }
            }
        }

        if ($Algorithm == ALGORITHM_WEIGHTED) {
            foreach ($this->Data as $Key => $Settings) {
                if ($Settings["Type"] == NODE_TYPE_CENTRAL) {
                    $this->Data[$Key]["X"] = $CenterX;
                    $this->Data[$Key]["Y"] = $CenterY;
                }
                if ($Settings["Type"] == NODE_TYPE_FREE) {
                    if (isset($Settings["Connections"])) {
                        $Connections = count($Settings["Connections"]);
                    } else {
                        $Connections = 0;
                    }

                    $Ring = $MaxConnections - $Connections;
                    $Angle = rand(0, 360);

                    $this->Data[$Key]["X"] = cos(deg2rad($Angle)) * ($Ring * $this->RingSize) + $CenterX;
                    $this->Data[$Key]["Y"] = sin(deg2rad($Angle)) * ($Ring * $this->RingSize) + $CenterY;
                }
            }
        } elseif ($Algorithm == ALGORITHM_CENTRAL) {
            /* Put a weight on each nodes */
            foreach ($this->Data as $Key => $Settings) {
                if (isset($Settings["Connections"])) {
                    $this->Data[$Key]["Weight"] = count($Settings["Connections"]);
                } else {
                    $this->Data[$Key]["Weight"] = 0;
                }
            }

            $MaxConnections = $MaxConnections + 1;
            for ($i = $MaxConnections; $i >= 0; $i--) {
                foreach ($this->Data as $Key => $Settings) {
                    if ($Settings["Type"] == NODE_TYPE_CENTRAL) {
                        $this->Data[$Key]["X"] = $CenterX;
                        $this->Data[$Key]["Y"] = $CenterY;
                    }
                    if ($Settings["Type"] == NODE_TYPE_FREE) {
                        if (isset($Settings["Connections"])) {
                            $Connections = count($Settings["Connections"]);
                        } else {
                            $Connections = 0;
                        }

                        if ($Connections == $i) {
                            $BiggestPartner = $this->getBiggestPartner($Key);
                            if ($BiggestPartner != "") {
                                $Ring = $this->Data[$BiggestPartner]["FreeZone"];
                                $Weight = $this->Data[$BiggestPartner]["Weight"];
                                $AngleDivision = 360 / $this->Data[$BiggestPartner]["Weight"];
                                $Done = false;
                                $Tries = 0;
                                while (!$Done && $Tries <= $Weight * 2) {
                                    $Tries++;
                                    $Angle = floor(rand(0, $Weight) * $AngleDivision);
                                    if (!isset($this->Data[$BiggestPartner]["Angular"][$Angle])
                                        || !isset($this->Data[$BiggestPartner]["Angular"])
                                    ) {
                                        $this->Data[$BiggestPartner]["Angular"][$Angle] = $Angle;
                                        $Done = true;
                                    }
                                }
                                if (!$Done) {
                                    $Angle = rand(0, 360);
                                    $this->Data[$BiggestPartner]["Angular"][$Angle] = $Angle;
                                }

                                $X = cos(deg2rad($Angle)) * ($Ring) + $this->Data[$BiggestPartner]["X"];
                                $Y = sin(deg2rad($Angle)) * ($Ring) + $this->Data[$BiggestPartner]["Y"];

                                $this->Data[$Key]["X"] = $X;
                                $this->Data[$Key]["Y"] = $Y;
                            }
                        }
                    }
                }
            }
        } elseif ($Algorithm == ALGORITHM_CIRCULAR) {
            $MaxConnections = $MaxConnections + 1;
            for ($i = $MaxConnections; $i >= 0; $i--) {
                foreach ($this->Data as $Key => $Settings) {
                    if ($Settings["Type"] == NODE_TYPE_CENTRAL) {
                        $this->Data[$Key]["X"] = $CenterX;
                        $this->Data[$Key]["Y"] = $CenterY;
                    }
                    if ($Settings["Type"] == NODE_TYPE_FREE) {
                        if (isset($Settings["Connections"])) {
                            $Connections = count($Settings["Connections"]);
                        } else {
                            $Connections = 0;
                        }

                        if ($Connections == $i) {
                            $Ring = $MaxConnections - $Connections;
                            $Angle = rand(0, 360);

                            $X = cos(deg2rad($Angle)) * ($Ring * $this->RingSize) + $CenterX;
                            $Y = sin(deg2rad($Angle)) * ($Ring * $this->RingSize) + $CenterY;

                            $MedianOffset = $this->getMedianOffset($Key, $X, $Y);

                            $this->Data[$Key]["X"] = $MedianOffset["X"];
                            $this->Data[$Key]["Y"] = $MedianOffset["Y"];
                        }
                    }
                }
            }
        } elseif ($Algorithm == ALGORITHM_RANDOM) {
            foreach ($this->Data as $Key => $Settings) {
                if ($Settings["Type"] == NODE_TYPE_FREE) {
                    $this->Data[$Key]["X"] = $CenterX + rand(-20, 20);
                    $this->Data[$Key]["Y"] = $CenterY + rand(-20, 20);
                }
                if ($Settings["Type"] == NODE_TYPE_CENTRAL) {
                    $this->Data[$Key]["X"] = $CenterX;
                    $this->Data[$Key]["Y"] = $CenterY;
                }
            }
        }
    }

    /**
     * Compute one pass
     */
    public function doPass()
    {
        /* Compute vectors */
        foreach ($this->Data as $Key => $Settings) {
            if ($Settings["Type"] != NODE_TYPE_CENTRAL) {
                unset($this->Data[$Key]["Vectors"]);

                $X1 = $Settings["X"];
                $Y1 = $Settings["Y"];

                /* Repulsion vectors */
                foreach ($this->Data as $Key2 => $Settings2) {
                    if ($Key != $Key2) {
                        $X2 = $this->Data[$Key2]["X"];
                        $Y2 = $this->Data[$Key2]["Y"];
                        $FreeZone = $this->Data[$Key2]["FreeZone"];

                        $Distance = $this->getDistance($X1, $Y1, $X2, $Y2);
                        $Angle = $this->getAngle($X1, $Y1, $X2, $Y2) + 180;

                        /* Nodes too close, repulsion occurs */
                        if ($Distance < $FreeZone) {
                            $Force = log(pow(2, $FreeZone - $Distance));
                            if ($Force > 1) {
                                $this->Data[$Key]["Vectors"][] = array(
                                    "Type"  => "R",
                                    "Angle" => $Angle % 360,
                                    "Force" => $Force
                                );
                            }
                        }
                    }
                }

                /* Attraction vectors */
                if (isset($Settings["Connections"])) {
                    foreach ($Settings["Connections"] as $ID => $NodeID) {
                        if (isset($this->Data[$NodeID])) {
                            $X2 = $this->Data[$NodeID]["X"];
                            $Y2 = $this->Data[$NodeID]["Y"];
                            $FreeZone = $this->Data[$Key2]["FreeZone"];

                            $Distance = $this->getDistance($X1, $Y1, $X2, $Y2);
                            $Angle = $this->getAngle($X1, $Y1, $X2, $Y2);

                            if ($Distance > $FreeZone) {
                                $Force = log(($Distance - $FreeZone) + 1);
                            } else {
                                $Force = log(($FreeZone - $Distance) + 1);
                                ($Angle = $Angle + 180);
                            }

                            if ($Force > 1) {
                                $this->Data[$Key]["Vectors"][] = array(
                                    "Type"  => "A",
                                    "Angle" => $Angle % 360,
                                    "Force" => $Force
                                );
                            }
                        }
                    }
                }
            }
        }

        /* Move the nodes accoding to the vectors */
        foreach ($this->Data as $Key => $Settings) {
            $X = $Settings["X"];
            $Y = $Settings["Y"];

            if (isset($Settings["Vectors"]) && $Settings["Type"] != NODE_TYPE_CENTRAL) {
                foreach ($Settings["Vectors"] as $ID => $Vector) {
                    $Type = $Vector["Type"];
                    $Force = $Vector["Force"];
                    $Angle = $Vector["Angle"];
                    $Factor = $Type == "A" ? $this->MagneticForceA : $this->MagneticForceR;

                    $X = cos(deg2rad($Angle)) * $Force * $Factor + $X;
                    $Y = sin(deg2rad($Angle)) * $Force * $Factor + $Y;
                }
            }

            $this->Data[$Key]["X"] = $X;
            $this->Data[$Key]["Y"] = $Y;
        }
    }

    /**
     * @return int|float
     */
    public function lastPass()
    {
        /* Put everything inside the graph area */
        foreach ($this->Data as $Key => $Settings) {
            $X = $Settings["X"];
            $Y = $Settings["Y"];

            if ($X < $this->X1) {
                $X = $this->X1;
            }
            if ($X > $this->X2) {
                $X = $this->X2;
            }
            if ($Y < $this->Y1) {
                $Y = $this->Y1;
            }
            if ($Y > $this->Y2) {
                $Y = $this->Y2;
            }

            $this->Data[$Key]["X"] = $X;
            $this->Data[$Key]["Y"] = $Y;
        }

        /* Dump all links */
        $Links = array();
        foreach ($this->Data as $Key => $Settings) {
            $X1 = $Settings["X"];
            $Y1 = $Settings["Y"];

            if (isset($Settings["Connections"])) {
                foreach ($Settings["Connections"] as $ID => $NodeID) {
                    if (isset($this->Data[$NodeID])) {
                        $X2 = $this->Data[$NodeID]["X"];
                        $Y2 = $this->Data[$NodeID]["Y"];

                        $Links[] = array(
                            "X1" => $X1,
                            "Y1" => $Y1,
                            "X2" => $X2,
                            "Y2" => $Y2,
                            "Source" => $Settings["Name"],
                            "Destination" => $this->Data[$NodeID]["Name"]
                        );
                    }
                }
            }
        }

        /* Check collisions */
        $Conflicts = 0;
        foreach ($this->Data as $Key => $Settings) {
            $X1 = $Settings["X"];
            $Y1 = $Settings["Y"];

            if (isset($Settings["Connections"])) {
                foreach ($Settings["Connections"] as $ID => $NodeID) {
                    if (isset($this->Data[$NodeID])) {
                        $X2 = $this->Data[$NodeID]["X"];
                        $Y2 = $this->Data[$NodeID]["Y"];

                        foreach ($Links as $IDLinks => $Link) {
                            $X3 = $Link["X1"];
                            $Y3 = $Link["Y1"];
                            $X4 = $Link["X2"];
                            $Y4 = $Link["Y2"];

                            if (!($X1 == $X3 && $X2 == $X4 && $Y1 == $Y3 && $Y2 == $Y4)) {
                                if ($this->intersect($X1, $Y1, $X2, $Y2, $X3, $Y3, $X4, $Y4)) {
                                    if ($Link["Source"] != $Settings["Name"]
                                        && $Link["Source"] != $this->Data[$NodeID]["Name"]
                                        && $Link["Destination"] != $Settings["Name"]
                                        && $Link["Destination"] != $this->Data[$NodeID]["Name"]
                                    ) {
                                        $Conflicts++;
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
        return $Conflicts / 2;
    }

    /**
     * Center the graph
     */
    public function center()
    {
        /* Determine the real center */
        $TargetCenterX = ($this->X2 - $this->X1) / 2 + $this->X1;
        $TargetCenterY = ($this->Y2 - $this->Y1) / 2 + $this->Y1;

        /* Get current boundaries */
        $XMin = $this->X2;
        $XMax = $this->X1;
        $YMin = $this->Y2;
        $YMax = $this->Y1;
        foreach ($this->Data as $Key => $Settings) {
            $X = $Settings["X"];
            $Y = $Settings["Y"];

            if ($X < $XMin) {
                $XMin = $X;
            }
            if ($X > $XMax) {
                $XMax = $X;
            }
            if ($Y < $YMin) {
                $YMin = $Y;
            }
            if ($Y > $YMax) {
                $YMax = $Y;
            }
        }
        $CurrentCenterX = ($XMax - $XMin) / 2 + $XMin;
        $CurrentCenterY = ($YMax - $YMin) / 2 + $YMin;

        /* Compute the offset to apply */
        $XOffset = $TargetCenterX - $CurrentCenterX;
        $YOffset = $TargetCenterY - $CurrentCenterY;

        /* Correct the points position */
        foreach ($this->Data as $Key => $Settings) {
            $this->Data[$Key]["X"] = $Settings["X"] + $XOffset;
            $this->Data[$Key]["Y"] = $Settings["Y"] + $YOffset;
        }
    }

    /**
     * Create the encoded string
     * @param Image $Object
     * @param string $Settings
     * @return array
     */
    public function drawSpring(Image $Object, array $Settings = array())
    {
        $this->pChartObject = $Object;

        $Pass = isset($Settings["Pass"]) ? $Settings["Pass"] : 50;
        $Retries = isset($Settings["Retry"]) ? $Settings["Retry"] : 10;
        $this->MagneticForceA = isset($Settings["MagneticForceA"]) ? $Settings["MagneticForceA"] : 1.5;
        $this->MagneticForceR = isset($Settings["MagneticForceR"]) ? $Settings["MagneticForceR"] : 2;
        $this->RingSize = isset($Settings["RingSize"]) ? $Settings["RingSize"] : 40;
        $DrawVectors = isset($Settings["DrawVectors"]) ? $Settings["DrawVectors"] : false;
        $DrawQuietZone = isset($Settings["DrawQuietZone"]) ? $Settings["DrawQuietZone"] : false;
        $CenterGraph = isset($Settings["CenterGraph"]) ? $Settings["CenterGraph"] : true;
        $TextPadding = isset($Settings["TextPadding"]) ? $Settings["TextPadding"] : 4;
        $Algorithm = isset($Settings["Algorithm"]) ? $Settings["Algorithm"] : ALGORITHM_WEIGHTED;

        $this->X1 = $Object->GraphAreaX1;
        $this->Y1 = $Object->GraphAreaY1;
        $this->X2 = $Object->GraphAreaX2;
        $this->Y2 = $Object->GraphAreaY2;

        $Conflicts = 1;
        $Jobs = 0;
        $this->History["MinimumConflicts"] = -1;
        while ($Conflicts != 0 && $Jobs < $Retries) {
            $Jobs++;

            /* Compute the initial settings */
            $this->firstPass($Algorithm);

            /* Apply the vectors */
            if ($Pass > 0) {
                for ($i = 0; $i <= $Pass; $i++) {
                    $this->doPass();
                }
            }

            $Conflicts = $this->lastPass();
            if ($this->History["MinimumConflicts"] == -1
                || $Conflicts < $this->History["MinimumConflicts"]
            ) {
                $this->History["MinimumConflicts"] = $Conflicts;
                $this->History["Result"] = $this->Data;
            }
        }

        $Conflicts = $this->History["MinimumConflicts"];
        $this->Data = $this->History["Result"];

        if ($CenterGraph) {
            $this->center();
        }

        /* Draw the connections */
        $Drawn = array();
        foreach ($this->Data as $Key => $Settings) {
            $X = $Settings["X"];
            $Y = $Settings["Y"];

            if (isset($Settings["Connections"])) {
                foreach ($Settings["Connections"] as $ID => $NodeID) {
                    if (!isset($Drawn[$Key])) {
                        $Drawn[$Key] = "";
                    }
                    if (!isset($Drawn[$NodeID])) {
                        $Drawn[$NodeID] = "";
                    }

                    if (isset($this->Data[$NodeID])
                        && !isset($Drawn[$Key][$NodeID])
                        && !isset($Drawn[$NodeID][$Key])
                    ) {
                        $Color = array(
                            "R" => $this->Default["LinkR"],
                            "G" => $this->Default["LinkG"],
                            "B" => $this->Default["LinkB"],
                            "Alpha" => $this->Default["Alpha"]
                        );

                        if (count($this->Links)) {
                            if (isset($this->Links[$Key][$NodeID]["R"])) {
                                $Color = array(
                                    "R" => $this->Links[$Key][$NodeID]["R"],
                                    "G" => $this->Links[$Key][$NodeID]["G"],
                                    "B" => $this->Links[$Key][$NodeID]["B"],
                                    "Alpha" => $this->Links[$Key][$NodeID]["Alpha"]
                                );
                            }

                            if (isset($this->Links[$Key][$NodeID]["Ticks"])) {
                                $Color["Ticks"] = $this->Links[$Key][$NodeID]["Ticks"];
                            }
                        }

                        $X2 = $this->Data[$NodeID]["X"];
                        $Y2 = $this->Data[$NodeID]["Y"];
                        $this->pChartObject->drawLine($X, $Y, $X2, $Y2, $Color);
                        $Drawn[$Key][$NodeID] = true;

                        if (isset($this->Links) && count($this->Links)) {
                            if (isset($this->Links[$Key][$NodeID]["Name"])
                                || isset($this->Links[$NodeID][$Key]["Name"])
                            ) {
                                $Name = isset($this->Links[$Key][$NodeID]["Name"])
                                    ? $this->Links[$Key][$NodeID]["Name"]
                                    : $this->Links[$NodeID][$Key]["Name"]
                                ;
                                $TxtX = ($X2 - $X) / 2 + $X;
                                $TxtY = ($Y2 - $Y) / 2 + $Y;

                                if ($X <= $X2) {
                                    $Angle = (360 - $this->getAngle($X, $Y, $X2, $Y2)) % 360;
                                } else {
                                    $Angle = (360 - $this->getAngle($X2, $Y2, $X, $Y)) % 360;
                                }
                                $Settings = $Color;
                                $Settings["Angle"] = $Angle;
                                $Settings["Align"] = TEXT_ALIGN_BOTTOMMIDDLE;
                                $this->pChartObject->drawText($TxtX, $TxtY, $Name, $Settings);
                            }
                        }
                    }
                }
            }
        }

        /* Draw the quiet zones */
        if ($DrawQuietZone) {
            foreach ($this->Data as $Key => $Settings) {
                $X = $Settings["X"];
                $Y = $Settings["Y"];
                $FreeZone = $Settings["FreeZone"];

                $this->pChartObject->drawFilledCircle(
                    $X,
                    $Y,
                    $FreeZone,
                    array("R" => 0, "G" => 0, "B" => 0, "Alpha" => 2)
                );
            }
        }


        /* Draw the nodes */
        foreach ($this->Data as $Key => $Settings) {
            $X = $Settings["X"];
            $Y = $Settings["Y"];
            $Name = $Settings["Name"];
            $FreeZone = $Settings["FreeZone"];
            $Shape = $Settings["Shape"];
            $Size = $Settings["Size"];

            $Color = array(
                "R" => $Settings["R"],
                "G" => $Settings["G"],
                "B" => $Settings["B"],
                "Alpha" => $Settings["Alpha"],
                "BorderR" => $Settings["BorderR"],
                "BorderG" => $Settings["BorderG"],
                "BorderB" => $Settings["BorderB"],
                "BorderApha" => $Settings["BorderAlpha"]
            );

            if ($Shape == NODE_SHAPE_CIRCLE) {
                $this->pChartObject->drawFilledCircle($X, $Y, $Size, $Color);
            } elseif ($Shape == NODE_SHAPE_TRIANGLE) {
                $Points = array();
                $Points[] = cos(deg2rad(270)) * $Size + $X;
                $Points[] = sin(deg2rad(270)) * $Size + $Y;
                $Points[] = cos(deg2rad(45)) * $Size + $X;
                $Points[] = sin(deg2rad(45)) * $Size + $Y;
                $Points[] = cos(deg2rad(135)) * $Size + $X;
                $Points[] = sin(deg2rad(135)) * $Size + $Y;
                $this->pChartObject->drawPolygon($Points, $Color);
            } elseif ($Shape == NODE_SHAPE_SQUARE) {
                $Offset = $Size / 2;
                $Size = $Size / 2;
                $this->pChartObject->drawFilledRectangle(
                    $X - $Offset,
                    $Y - $Offset,
                    $X + $Offset,
                    $Y + $Offset,
                    $Color
                );
            }

            if ($Name != "") {
                $LabelOptions = array(
                    "R" => $this->Labels["R"],
                    "G" => $this->Labels["G"],
                    "B" => $this->Labels["B"],
                    "Alpha" => $this->Labels["Alpha"]
                );

                if ($this->Labels["Type"] == LABEL_LIGHT) {
                    $LabelOptions["Align"] = TEXT_ALIGN_BOTTOMLEFT;
                    $this->pChartObject->drawText($X, $Y, $Name, $LabelOptions);
                } elseif ($this->Labels["Type"] == LABEL_CLASSIC) {
                    $LabelOptions["Align"] = TEXT_ALIGN_TOPMIDDLE;
                    $LabelOptions["DrawBox"] = true;
                    $LabelOptions["BoxAlpha"] = 50;
                    $LabelOptions["BorderOffset"] = 4;
                    $LabelOptions["RoundedRadius"] = 3;
                    $LabelOptions["BoxRounded"] = true;
                    $LabelOptions["NoShadow"] = true;

                    $this->pChartObject->drawText($X, $Y + $Size + $TextPadding, $Name, $LabelOptions);
                }
            }
        }

        /* Draw the vectors */
        if ($DrawVectors) {
            foreach ($this->Data as $Key => $Settings) {
                $X1 = $Settings["X"];
                $Y1 = $Settings["Y"];

                if (isset($Settings["Vectors"]) && $Settings["Type"] != NODE_TYPE_CENTRAL) {
                    foreach ($Settings["Vectors"] as $ID => $Vector) {
                        $Type = $Vector["Type"];
                        $Force = $Vector["Force"];
                        $Angle = $Vector["Angle"];
                        $Factor = $Type == "A" ? $this->MagneticForceA : $this->MagneticForceR;
                        $Color = $Type == "A"
                            ? array("FillR" => 255, "FillG" => 0, "FillB" => 0)
                            : array("FillR" => 0, "FillG" => 255, "FillB" => 0)
                        ;

                        $X2 = cos(deg2rad($Angle)) * $Force * $Factor + $X1;
                        $Y2 = sin(deg2rad($Angle)) * $Force * $Factor + $Y1;

                        $this->pChartObject->drawArrow($X1, $Y1, $X2, $Y2, $Color);
                    }
                }
            }
        }

        return array("Pass" => $Jobs, "Conflicts" => $Conflicts);
    }

    /**
     * Return the distance between two points
     * @param int $X1
     * @param int $Y1
     * @param int $X2
     * @param int $Y2
     * @return int|float
     */
    public function getDistance($X1, $Y1, $X2, $Y2)
    {
        return sqrt(($X2 - $X1) * ($X2 - $X1) + ($Y2 - $Y1) * ($Y2 - $Y1));
    }

    /**
     * Return the angle made by a line and the X axis
     * @param int $X1
     * @param int $Y1
     * @param int $X2
     * @param int $Y2
     * @return int|float
     */
    public function getAngle($X1, $Y1, $X2, $Y2)
    {
        $Opposite = $Y2 - $Y1;
        $Adjacent = $X2 - $X1;
        $Angle = rad2deg(atan2($Opposite, $Adjacent));

        return $Angle > 0 ? $Angle : 360 - abs($Angle);
    }

    /**
     * @param int $X1
     * @param int $Y1
     * @param int $X2
     * @param int $Y2
     * @param int $X3
     * @param int $Y3
     * @param int $X4
     * @param int $Y4
     * @return boolean
     */
    public function intersect($X1, $Y1, $X2, $Y2, $X3, $Y3, $X4, $Y4)
    {
        $A = (($X3 * $Y4 - $X4 * $Y3) * ($X1 - $X2) - ($X1 * $Y2 - $X2 * $Y1) * ($X3 - $X4));
        $B = (($Y1 - $Y2) * ($X3 - $X4) - ($Y3 - $Y4) * ($X1 - $X2));

        if ($B == 0) {
            return false;
        }
        $Xi = $A / $B;

        $C = ($X1 - $X2);
        if ($C == 0) {
            return false;
        }
        $Yi = $Xi * (($Y1 - $Y2) / $C) + (($X1 * $Y2 - $X2 * $Y1) / $C);

        if ($Xi >= min($X1, $X2)
            && $Xi >= min($X3, $X4)
            && $Xi <= max($X1, $X2)
            && $Xi <= max($X3, $X4)
            && $Yi >= min($Y1, $Y2)
            && $Yi >= min($Y3, $Y4)
            && $Yi <= max($Y1, $Y2)
            && $Yi <= max($Y3, $Y4)
        ) {
            return true;
        }

        return false;
    }
}
