<?php

namespace SparkPlug\Com\Noccy\Watcher\Monitor;

use SparkPlug\Com\Noccy\Watcher\Rule;

class InotifyMonitor implements MonitorInterface
{
    private array $rules = [];

    private array $watched = [];

    private array $modified = [];

    private $fd;

    public function __construct()
    {
        $this->fd = \inotify_init();   
    }

    public function __destruct()
    {
        if (is_resource($this->fd)) fclose($this->fd);
    }

    /**
     * {@inheritDoc}
     */
    public function add(Rule $rule)
    {
        $this->rules[] = $rule;

        $paths = $rule->getWatchedFiles();
        $check = [];
        foreach ($paths as $path) {
            if (str_contains($path, '*')) {
                $check = array_merge($check, glob($path));
            } else {
                $check[] = $path;
            }
        }
        $dirs = [];
        foreach ($check as $path) {
            $dir = is_dir($path) ? $path : dirname($path);
            if (!array_key_exists($dir, $dirs)) {
                $dirs[$dir] = $rule;
                \inotify_add_watch($this->fd, $dir, \IN_ATTRIB);
            }
        }
        $this->watched = array_merge($this->watched, $dirs);

    }

    /**
     * {@inheritDoc}
     */
    public function getModified(): array
    {
        $mod = $this->modified;
        $this->modified = [];
        return $mod;
    }

    /**
     * {@inheritDoc}
     */
    public function getWatched(): array
    {
        return [];        
    }

    public function loop()
    {
        $read = [ $this->fd ];
        $write = null;
        $except = null;
        $changed = [];
        while (stream_select($read,$write,$except,0)) {
            $events = \inotify_read($this->fd);
            foreach ($events as $event) {
                $changed[] = $event['name'];
            }
        }

        foreach ($changed as $file) {
            foreach ($this->watched as $dir=>$rule) {
                if (file_exists($dir."/".$file)) {
                    if (!in_array($rule, $this->modified)) {
                        printf("~ modified: %s (%s)\n", $dir."/".$file, $rule->getName());
                        $this->modified[] = $rule;
                    }
                }
            }
        }
    }
}