<?php

namespace NoccyLabs\Shell;

use NoccyLabs\Shell\LineRead;

abstract class Shell
{
    protected $prompt;

    protected $promptStyle;
    
    protected $commandStyle;

    public function __construct(array $config=[])
    {
        $this->configure($config);
    }

    abstract protected function configure(array $config);

    public function addCommand($command, callable $handler=null)
    {
        if (!$handler) {
            if (!($command instanceof Command)) {
                throw new \RuntimeException("Handler is not callable nor a Command");
            }
            $command->setShell($this);
            $this->commands[$command->getName()] = $command;
        } else {
            $this->commands[$command] = $handler;
        }
    }

    public function execute($command)
    {
        if (is_array($command)) {
            foreach ($command as $cmd) {
                $this->execute($cmd);
            }
            return;
        }

        $buffer = str_getcsv($command, " ", "\"", "\\");

        if (count($buffer)>0) {
            $this->onCommand($buffer);
        }
    }
    
    protected function onCommand($buffer)
    {
        $this->executeBuffer($buffer);
    }

    protected function executeBuffer(array $buffer)
    {
        $commandName = array_shift($buffer);
        if (array_key_exists($commandName, $this->commands)) {
            $command = $this->commands[$commandName];
            if ($command instanceof Command) {
                $command->run($buffer);
            } else {
                call_user_func_array($command,$buffer);
            }
            return;
        }
        $this->writeln("Bad command: ".$commandName);
    }

    public function writeln($output)
    {
        echo "\r\e[K\e[0m".$output."\n";
    }
    
    protected function onUpdate()
    {
    }

    public function setPrompt($prompt)
    {
        $this->prompt = $prompt;
    }

    public function setPromptStyle($style)
    {
        $this->promptStyle = $style;
    }
    
    public function setCommandStyle($style)
    {
        $this->commandStyle = $style;
    }

    public function run()
    {
        $lineRead = new LineRead();
        
        $lineRead->setCommandStyle($this->commandStyle);

        $this->running = true;

        do {
            $lineRead->setPrompt($this->prompt, $this->promptStyle);
            $buffer = $lineRead->update();
            if ($buffer == "\x03") {
                $this->stop();
                continue;
            }
            ob_start();
            $this->onUpdate();
            if ($buffer !== null) {
                $this->execute($buffer);
            }
            $buf = ob_get_contents();
            ob_end_clean();
            if ($buf) {
                $lineRead->erase();
                echo str_replace("\n", "\r\n", rtrim($buf)."\n");
                $lineRead->redraw();
            }
            usleep(10000);
        } while ($this->running);

    }

    public function stop()
    {
        $this->running = false;
    }
}