#!/usr/bin/php
<?php
const COMPOSE_FILE = "docker-compose.yml";
const COMPOSE_BINARY = "docker-compose";
function cin($trim = true, $lower = true)
{
    $input = fgets(STDIN);
    if ($trim) {
        $input = trim($input);
    }
    if ($lower) {
        $input = strtolower($input);
    }
    return $input;
}

function println($w)
{
    echo $w . "\n";
}

class DecomposerApp
{


    /**
     * @var false|string
     */
    private $root;

    public function __construct()
    {
        $this->checkBinary();
        $this->root = getcwd();
        println("Working in directory: " . $this->root);

        $this->checkComposeFile();

        $existing = false;

        if ($this->checkRunningContainers()) {
            $existing = true;
            println("There are existing containers. Do you want to export them? [y/n]");

            if (cin() != "y") {
                println("Canceling...");
                return;
            }
        } else {
            $this->startContainers();
        }

        if ($this->checkRunningContainers() && count($this->containerNames) > 0) {
            println("Exporting " . count($this->containerNames) . " images...");
            foreach ($this->containerNames as $name) {
                $this->exportContainer($name);
            }
        } else {
            throw new RuntimeException("Something went wrong. There is no containers detected.");
        }

        if($existing){
            println("Do you want to remove running containers? [y/n]");
            if (cin() == "y") {
                $this->removeContainers();
            }
        }else{
            $this->removeContainers();
        }



        println("Done");
    }

    function startContainers()
    {
        println("Starting containers...");
        println(shell_exec("docker-compose up -d"));
    }

    function exportContainer($name)
    {
        println("Creating image of " . $name . "...");
        println(shell_exec("docker commit " . $name . " " . $name));
        println("Exporting image to file...");
        println(shell_exec("docker save -o " . $name . ".tar " . $name . ":latest"));
        println("Removing image...");
        println(shell_exec("docker image rm " . $name . ":latest"));

        if (!file_exists($name . ".tar")) {
            throw new RuntimeException("Unable to find output image file");
        }
    }

    function removeContainers()
    {
        println("Removing containers...");
        println(shell_exec("docker-compose down -v --remove-orphans"));
    }

    function checkBinary()
    {
        $compose = @shell_exec("which " . COMPOSE_BINARY);

        if (!file_exists(trim($compose))) {
            throw new RuntimeException(COMPOSE_BINARY . " binary was not found in PATH");
        }
    }

    function checkComposeFile()
    {
        if (!file_exists($this->root . "/" . COMPOSE_FILE)) {
            throw new RuntimeException(COMPOSE_FILE . " was not found in " . $this->root);
        }
    }

    function checkRunningContainers(): bool
    {
        $running_data = @shell_exec("docker-compose ps");
        $running_data = explode("\n", trim($running_data));

        if (count($running_data) > 2) {
            $this->containerNames = [];
            for ($i = 2; $i < count($running_data); $i++) {
                $parts = explode(" ", $running_data[$i], 2);
                $this->containerNames[] = $parts[0];
            }
            foreach ($running_data as $row) {
                println(trim($row));
            }
            return true;
        }

        return false;
    }

    private $containerNames = [];
}


try {
    $app = new DecomposerApp();


} catch (Exception $e) {
    echo "Error: " . $e->getMessage() . "\n";
    exit(1);
} finally {
    echo "\n";
}