<?php

final class ArticleManager
{
    const BASE_PATH = "./data/articles";

    public static function get(string $fullref): Article
    {
        $serial_path = "./data/serial/$fullref.pobj";
        return is_file($serial_path) ?
            unserialize(file_get_contents($serial_path)) :
            unserialize(file_get_contents("./data/serial/default.pobj"));
    }

    public static function getMultiple(array $fullrefs): array
    {
        $articles = [];
        foreach ($fullrefs as $fullref) {
            $articles[] = self::get($fullref);
        }
        return $articles;
    }

    public static function getNewest(): Article
    {
        $dot_dirs = [".", ".."];
        $years = array_diff(scandir(self::BASE_PATH, SCANDIR_SORT_DESCENDING), $dot_dirs);
        $year = $years[0];
        $path = self::BASE_PATH . "/$year";
        $months = array_diff(scandir($path, SCANDIR_SORT_DESCENDING), $dot_dirs);
        $month = $months[0];
        $path = "$path/$month";
        $days = array_diff(scandir($path, SCANDIR_SORT_DESCENDING), $dot_dirs);
        $day = $days[0];
        $path = "$path/$day";
        foreach (array_diff(scandir($path, SCANDIR_SORT_DESCENDING), $dot_dirs) as $file) {
            $file_path = "$path/$file";
            if (pathinfo($file_path, PATHINFO_EXTENSION) !== "txt") {
                continue;
            }
            $ref = substr($file, 0, -4);
            break;
        }
        return self::get("$year$month$day$ref");
    }

    public static function getLatestArticles(int $count): array
    {
        $dot_dirs = [".", ".."];
        $articles = [];
        foreach (array_diff(scandir(self::BASE_PATH, SCANDIR_SORT_DESCENDING), $dot_dirs) as $year) {
            $year_path = self::BASE_PATH . "/$year";
            foreach (array_diff(scandir($year_path, SCANDIR_SORT_DESCENDING), $dot_dirs) as $month) {
                $month_path = "$year_path/$month";
                foreach (array_diff(scandir($month_path, SCANDIR_SORT_DESCENDING), $dot_dirs) as $day) {
                    $day_path = "$month_path/$day";
                    foreach (array_diff(scandir($day_path, SCANDIR_SORT_DESCENDING), $dot_dirs) as $file) {
                        $file_path = "$day_path/$file";
                        if (pathinfo($file_path, PATHINFO_EXTENSION) !== "txt") {
                            continue;
                        }
                        $articles[] = self::getArticle($file_path);
                        if (count($articles) === $count) {
                            return $articles;
                        }
                    }
                }
            }
        }
        return $articles;
    }

    public static function getAll(): array
    {
        $dot_dirs = [".", ".."];
        $dates = [];
        foreach (array_diff(scandir(self::BASE_PATH, SCANDIR_SORT_DESCENDING), $dot_dirs) as $year) {
            $year_path = self::BASE_PATH . "/$year";
            foreach (array_diff(scandir($year_path, SCANDIR_SORT_DESCENDING), $dot_dirs) as $month) {
                $month_path = "$year_path/$month";
                foreach (array_diff(scandir($month_path, SCANDIR_SORT_DESCENDING), $dot_dirs) as $day) {
                    $day_path = "$month_path/$day";
                    $date = "$year$month$day";
                    foreach (array_diff(scandir($day_path, SCANDIR_SORT_DESCENDING), $dot_dirs) as $file) {
                        $file_path = "$day_path/$file";
                        if (pathinfo($file_path, PATHINFO_EXTENSION) !== "txt") {
                            continue;
                        }
                        if (!isset($dates["$date"])) {
                            $dates["$date"] = new ArticleDate("$day/$month/$year");
                        }
                        $dates["$date"]->articles[] = self::getArticle($file_path);
                    }
                }
            }
        }
        return $dates;
    }

    private static function getArticle(string $file_path): Article
    {
        $pattern = "|(./data)/articles/([0-9]+)/([0-9]+)/([0-9]+)/([0-9]+)\.txt|";
        $replacement = "$1/serial/$2$3$4$5.pobj";
        $serial_path = preg_replace($pattern, $replacement, $file_path);
        return file_exists($serial_path) ?
            unserialize(file_get_contents($serial_path)) :
            self::createArticle($file_path, $serial_path);
    }

    private static function createArticle(string $file_path, string $serial_path): Article
    {
        $parser = new ArticleParser();
        $article = $parser->parse($file_path);
        file_put_contents($serial_path, serialize($article));
        TagManager::add($article->tags, substr(basename($serial_path), 0, -5));
        return $article;
    }
}