<?php

namespace App\Helpers;

use Illuminate\Database\Capsule\Manager as DB;

class DateFormatter
{
    private static $defaultFormat = 'd/m/Y';
    private static $cachedFormat = null;

    /**
     * Format a date according to the company's configuration.
     *
     * @param string|null $date The date string (Y-m-d or Y-m-d H:i:s).
     * @param bool $includeTime Whether to include time in the formatted string.
     * @return string
     */
    public static function format(?string $date, bool $includeTime = false): string
    {
        if (empty($date)) {
            return '';
        }

        // Try to detect if date is already formatted (simple check for '/')
        if (strpos($date, '/') !== false) {
            return $date;
        }

        try {
            $format = self::getCompanyDateFormat();
            
            // If the format is just date but time is requested, append time format
            if ($includeTime) {
                // Heuristic: if format doesn't seem to have time, add it
                if (strpos($format, 'H') === false) {
                    $format .= ' H:i';
                }
            }

            $timestamp = strtotime($date);
            if ($timestamp === false) {
                return $date; // Return original if parsing fails
            }

            return date($format, $timestamp);

        } catch (\Exception $e) {
            // Fallback
            return date(self::$defaultFormat . ($includeTime ? ' H:i' : ''), strtotime($date));
        }
    }

    /**
     * Get the date format for the current company.
     * Caches the result in memory (static property) and session.
     *
     * @return string
     */
    private static function getCompanyDateFormat(): string
    {
        if (self::$cachedFormat) {
            return self::$cachedFormat;
        }

        // Check session
        if (isset($_SESSION['bus_date_format'])) {
            self::$cachedFormat = $_SESSION['bus_date_format'];
            return self::$cachedFormat;
        }

        // Fetch from database if user is logged in
        if (isset($_SESSION['user_bus_id'])) {
            try {
                $busId = $_SESSION['user_bus_id'];
                $company = DB::table('bus')
                    ->where('bus_id', $busId)
                    ->select('bus_date_format')
                    ->first();

                if ($company && !empty($company->bus_date_format)) {
                    $_SESSION['bus_date_format'] = $company->bus_date_format;
                    self::$cachedFormat = $company->bus_date_format;
                    return self::$cachedFormat;
                }
            } catch (\Exception $e) {
                // Log error if needed, but return default for now
            }
        }

        // Fallback default
        self::$cachedFormat = self::$defaultFormat;
        return self::$cachedFormat;
    }
    
    /**
     * Converts a formatted date back to MySQL format (Y-m-d).
     * 
     * @param string $date Formatted date string
     * @return string|null Y-m-d formatted date or null on failure
     */
    public static function toMySQL(string $date): ?string
    {
        if (empty($date)) {
            return null;
        }
        
        // If already Y-m-d (contains - and no /)
        if (strpos($date, '-') !== false && strpos($date, '/') === false) {
            return $date;
        }

        // Try to parse from company format
        $format = self::getCompanyDateFormat();
        $d = \DateTime::createFromFormat($format, $date);
        
        if ($d && $d->format($format) === $date) {
            return $d->format('Y-m-d');
        }
        
        // Try common fallback formats
        $formats = ['d/m/Y', 'm/d/Y', 'Y/m/d'];
        foreach ($formats as $fmt) {
            $d = \DateTime::createFromFormat($fmt, $date);
            if ($d && $d->format($fmt) === $date) {
                return $d->format('Y-m-d');
            }
        }
        
        return null;
    }
}