<?php
namespace libTononix;

require_once("vendor/autoload.php");
use Noodlehaus\Config;
use \Noodlehaus\Parser\Json;
use \Noodlehaus\Parser\Properties;
use \Noodlehaus\Parser\Xml;

class KernelManagement
{

    protected $cKernelVersion;
    protected $cKernelName;
    protected $cKernelFeatures;
    protected $cKernelBinary;
    protected $cKernelHash;  

    private $cBootPath;
    private $aInstalledKernels;
    private $oConfiguration;
    private $cPrefixPath;
    private $aPartitionInfo;
    private $aBootConfiguration;
    private $abootimg;
        
	function __construct()
	{
		if(!defined("IN_PREFIX"))
        {
            $this->cBootPath = "/boot";
        } else {
            if(!getenv("EPREFIX"))
            {
            // We're gonna assume the directory, we seem to be inside a prefix but the EPREFIX variable is missing.
            $this->cBootPath = "/home/phablet/.local/system/boot";
            $this->cPrefixPath = "/home/phablet/.local/system";
            } else {
                $this->cBootPath = getenv("EPREFIX") . "/boot";
                $this->cPrefixPath = getenv("EPREFIX");
            }
        }
        // Genkernel is nice enough to make a symlink to the last compiled kernel, so we'll use that.
        $this->cKernelBinary = realpath($this->cBootPath."/kernel");
        $this->cKernelHash = md5(file_get_contents($this->cKernelBinary));
        
        $this->loadConfiguration();
	
        if(!$this->aInstalledKernels)
        {
            // TODO: Replace this with an actual error code indicating the configuration file is not set up.    
            $this->doLibraryFirstInit();
        }
        

	}

    private function saveConfiguration()
    {
        $this->oConfiguration->set("device.installed-kernels", json_encode($this->aInstalledKernels));
        $this->oConfiguration->set("device.info.partitions", $this->aPartitionInfo);
        $this->oConfiguration->set("device.boot.configuration", $this->aBootConfiguration);
        $this->oConfiguration->toFile($this->cPrefixPath."/etc/tononixOS/kernel.conf", new \Noodlehaus\Writer\Xml());
    }

    private function installKernel($kernelVersion = "3.4.0107", $kernelPath = null)
    {
        if(!$kernelPath)
        {
            $kernelPath = realpath($this->cPrefixPath."/boot/kernel");
        }
        // TODO: Finish Function
    }

    private function loadConfiguration()
    {
        $this->oConfiguration = null;
        $this->aInstalledKernels = null;
        $this->aPartitionInfo = null;
        $this->aBootConfiguration = null;

        $this->oConfiguration = new Config($this->cPrefixPath."/etc/tononixOS/kernel.conf", New Xml);
        $this->aInstalledKernels = json_decode($this->oConfiguration->get("device.installed-kernels"));
        $this->aPartitionInfo = $this->oConfiguration->get("device.info.partitions");
        $this->aBootConfiguration = $this->oConfiguration->get("device.boot.configuration");

    }

    public function getPartitionNode($sPartitionNode)
    {
        if(key_exists($sPartitionNode, $this->aPartitionInfo))
        {
            return $this->aPartitionInfo[$sPartitionNode];
        }
    }


    public function retrieveCurrentInstalledBootImage($storePath = null)
    {
        if(!$storePath)
        {
            $storePath = $this->cPrefixPath."/boot/old_boot.img";
        }
        if(!$this->aPartitionInfo)
        {
            $this->detectPartitionLayout();
        }
        
        exec("dd if=".$this->aPartitionInfo['kernel']." of=".$storePath);
        
    }

    // Pulls currently installed boot image from the defined boot partition, then extracts it with abootimg.
    public function extractCurrentInstalledBootImage()
    {
        if(!`which abootimg`)
        {
            return false;
        } 
        $this->retrieveCurrentInstalledBootImage();
        $pwd = getcwd();
        chdir($this->cPrefixPath."/boot");
        exec("abootimg -x old_boot.img");
        chdir($pwd);
        
    }

    private function __getBootSlot()
    {
        // This will allow us to know what boot slot we're supposed to be flashing into, perhaps we can make a treble compatible system updater with this?
        $bootSlot = trim(`getprop ro.boot.slot_suffix`);
        if(empty($bootSlot))
        {
            $bootSlot = "";
        }
        return $bootSlot;
    }

    public function installKernelTree($branch = 'flo', $repository = "https://tonoxisisle.services/git/tononixOS/ubports_kernel_google_msm", $kernelName = "3.4.y-tononixOS")
    {
        $git = new CzProject\GitPhp\Git;
        $repo = $git->cloneRepository($repository, $_ENV['HOME']."/.local/system/usr/src/".$kernelName);
        if(!empty($branch))
        {
            $repo->checkout($branch);
        }
        $repo->pull();
        $cwd = getcwd();
        chdir($_ENV['HOME']."/.local/system/usr/src/".$kernelName);
        $kVersion = shell_exec("make kernelversion");
        if(empty($kVersion)) {
            $versionArray = explode("-", $kernelName);
            $kVersion = $versionArray[0];
        }
        // Until we implement the Kernel Features detection, we're going to null it out for the NYI string
        $this->addInstalledKernel($kVersion, $_ENV['HOME']."/.local/system/usr/src/".$kernelName, null, $kernelName);
    }

    public function removeKernelTree($kernelName)
    {
        
    }

    public function buildKernel($kernelName)
    {

    }

    public function detectBootConfiguration()
    {
        if(!file_exists($this->cPrefixPath."/boot/old_boot.img"))
        {
            $this->extractCurrentInstalledBootImage();
        }

        $aboot = new Config($this->cPrefixPath."/boot/bootimg.cfg", new Properties);
        $this->aBootConfiguration = array();
        $this->aBootConfiguration['bootsize'] = $aboot->get("bootsize");
        $this->aBootConfiguration['pagesize'] = $aboot->get("pagesize");
        $this->aBootConfiguration['kerneladdr'] = $aboot->get("kerneladdr");
        $this->aBootConfiguration['ramdiskaddr'] = $aboot->get("ramdiskaddr");
        $this->aBootConfiguration['secondaddr'] = $aboot->get("secondaddr");
        $this->aBootConfiguration['tagsaddr'] = $aboot->get("tagsaddr");
        $this->aBootConfiguration['cmdline'] = $aboot->get("cmdline");
        $bootSlot = $this->__getBootSlot();
        if(!empty($bootSlot)) $this->aBootConfiguration['bootslot'] = $bootSlot;
        $this->saveConfiguration();
    }

    function detectPartitionLayout()
    {
        $partitionLayout = array();
        if(!is_dir("/dev/disk"))
        {
            return false;
        }
        $partitionLayout['system'] = realpath("/dev/disk/by-partlabel/system");
        $partitionLayout['cache'] = realpath("/dev/disk/by-partlabel/cache");
        $partitionLayout['userdata'] = realpath("/dev/disk/by-partlabel/userdata");
        $partitionLayout['bootloader'] = realpath("/dev/disk/by-partlabel/aboot");
        $partitionLayout['bootloaderb'] = realpath("/dev/disk/by-partlabel/abootb");
        $partitionLayout['baseband'] = realpath("/dev/disk/by-partlabel/radio");
        $partitionLayout['recovery'] = realpath("/dev/disk/by-partlabel/recovery");
        $partitionLayout['kernel'] = realpath("/dev/disk/by-partlabel/boot");
        $partitionLayout['modemst1'] = realpath("/dev/disk/by-partlabel/modemst1");
        $partitionLayout['modemst2'] = realpath("/dev/disk/by-partlabel/modemst2");

        $this->aPartitionInfo = $partitionLayout;
        $this->saveConfiguration();
    }

    private function addInstalledKernel($version, $path, $aFeaturesList = "NYI", $sKernelName = null)
    {
        $this->aInstalledKernels[] = array("path" => "$path",
                                           "version" => "$version",
                                           "features" => $aFeaturesList,
                                           "name" => "$sKernelName");
        return;
    }

    private function delInstalledKernel($version)
    {
        
    }

    function doLibraryFirstInit()
    {
       if(file_exists($this->cPrefixPath."/boot/kernel"))
       {
              // We already have an installed kernel, let's record it as our first installed kernel in the array.
              $this->addInstalledKernel("0.0.0-stock", realpath($this->cPrefixPath."/boot/kernel"));          
              
       }
       $this->detectPartitionLayout();
       $this->detectBootConfiguration();
       $this->saveConfiguration();
       $this->loadConfiguration();
       return true;
    }
}