/**
 * formatters.js - Data formatting utilities
 * 
 * This module contains utility functions for formatting time, durations, and other data.
 */

/**
 * Format time to GMT+4 timezone (Asia/Dubai)
 * This timezone is used consistently throughout the application:
 * - PostgreSQL database is set to Asia/Dubai timezone (UTC+4)
 * - Backend uses UTC internally but stores in Asia/Dubai in database
 * - All displayed times on frontend use this timezone for consistency
 * 
 * @param {string} dateTimeStr - ISO date-time string
 * @returns {string} Formatted time string in GMT+4
 */
export function formatTimeToGMT4(dateTimeStr) {
    if (!dateTimeStr) return 'N/A';
    
    try {
        const date = new Date(dateTimeStr);
        // Format the time using the Etc/GMT-4 timezone, which represents GMT+4.
        // The locale 'en-US' or 'en-GB' can be used for formatting conventions like AM/PM.
        return date.toLocaleTimeString('en-US', { 
            hour: '2-digit', 
            minute: '2-digit',
            hour12: true,
            timeZone: 'Etc/GMT-4' 
        }) + ' (GMT+4)';
    } catch (error) {
        console.error("Error formatting time to GMT+4:", error, "Input:", dateTimeStr);
        return 'Invalid Date'; // Or return N/A or the original string
    }
}

/**
 * Convert decimal hours to hours and minutes format
 * @param {number} decimalHours - Hours in decimal format
 * @returns {string} Formatted duration string
 */
export function formatDurationHours(decimalHours) {
    if (decimalHours === null || decimalHours === undefined) return 'N/A';
    
    const hours = Math.floor(decimalHours);
    const minutes = Math.round((decimalHours - hours) * 60);
    
    if (hours === 0) {
        return `${minutes} min`;
    } else if (minutes === 0) {
        return `${hours} hr`;
    } else {
        return `${hours} hr ${minutes} min`;
    }
}