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// 1: UNDERSTANDING THE DATE OBJECT

// let currentDate = new Date();

// console.log(currentDate);

// let birthday = new Date('1995-08-15');

// let specificDate = new Date(2025, 0, 1); // January 1, 2025

// 2: CREATING DATES - DIFFERENT METHODS

// let currentDate = new Date();

// let date1 = new Date('October 14, 2025');

// let date2 = new Date('2025-10-14');

// let date3 = new Date('2025-10-14T10:30:00');

// console.log(date1, date2, date3)

// // new Date(year, month, day, hours, minutes, seconds, milliseconds)

// let date4 = new Date(2025, 9, 14); // October 14, 2025

// let date5 = new Date(2025, 9, 14, 10, 30, 0); // with time

// let date6 = new Date(0); // January 1, 1970

// let date7 = new Date(1697280000000); // specific timestamp

// 3: GETTING DATE COMPONENTS

let today = new Date();

// Getting date components

// console.log(today.getFullYear()); // 2025

// console.log(today.getMonth()); // 9 (October, remember 0-indexed!)

// console.log(today.getDate()); // 14 (day of month)

// console.log(today.getDay()); // 2 (Tuesday, Sunday is 0)

// // Getting time components

// console.log(today.getHours()); // Current hour (0-23)

// console.log(today.getMinutes()); // Current minutes

// console.log(today.getSeconds()); // Current seconds

// console.log(today.getMilliseconds()); // Milliseconds

// console.log(today.getTime()); // Milliseconds since January 1, 1970

// console.log(Date.now()); // Same thing, but simpler for current time

// 4: SETTING DATE COMPONENTS

// let myDate = new Date();

// myDate.setFullYear(2026);

// myDate.setMonth(11); // December

// myDate.setDate(25); // Christmas!

// myDate.setHours(12);

// myDate.setMinutes(30);

// myDate.setSeconds(0);

// console.log(myDate);

// myDate.setFullYear(2026, 11, 25); // Year, Month, Day

// 5: DATE FORMATTING

// let date = new Date();

// console.log(date.toString());

// // "Tue Oct 14 2025 10:30:45 GMT+0600"

// console.log(date.toDateString());

// // "Tue Oct 14 2025"

// console.log(date.toTimeString());

// // "10:30:45 GMT+0600"

// console.log(date.toLocaleDateString());

// // "10/14/2025" (format depends on locale)

// console.log(date.toLocaleTimeString());

// // "10:30:45 AM"

// console.log(date.toLocaleString());

// // "10/14/2025, 10:30:45 AM"

// console.log(date.toISOString());

// "2025-10-14T04:30:45.000Z"

// let date = new Date();

// let options = {

// weekday: 'long',

// year: 'numeric',

// month: 'long',

// day: 'numeric'

// };

// console.log(date.toLocaleDateString('en-US', options));

// // "Tuesday, October 14, 2025"

// console.log(date.toLocaleDateString('bn-BD', options));

// // "মঙ্গলবার, ১৪ অক্টোবর, ২০২৫"

// 6: PRACTICAL EXAMPLES

// Example 1: Age Calculator

// function calculateAge(birthDate) {

// let today = new Date();

// let birth = new Date(birthDate);

// let age = today.getFullYear() - birth.getFullYear();

// let monthDiff = today.getMonth() - birth.getMonth();

// if (monthDiff < 0 || (monthDiff === 0 && today.getDate() < birth.getDate())) {

// age--;

// }

// return age;

// }

// console.log(calculateAge('1995-08-15')); // Age in years

// Example 2: Days Until Event

// function daysUntil(eventDate) {

// let today = new Date();

// let event = new Date(eventDate);

// let difference = event.getTime() - today.getTime();

// let days = Math.ceil(difference / (1000 * 60 * 60 * 24));

// return days;

// }

// console.log(daysUntil('2025-12-31')); // Days until New Year

// Example 3: Greeting Based on Time

// function getGreeting() {

// let hour = new Date().getHours();

// if (hour < 12) {

// return "Good Morning!";

// } else if (hour < 18) {

// return "Good Afternoon!";

// } else {

// return "Good Evening!";

// }

// console.log(getGreeting());

// 7: COMMON PITFALLS

// Pitfall 1: Month Index

// WRONG - This is November, not October!

let wrong = new Date(2025, 10, 14);

// CORRECT - October

let correct = new Date(2025, 9, 14);

// Pitfall 2: Date Strings

console.log(new Date('2025-10-14')); // Might be UTC

console.log(new Date('10/14/2025')); // Local time

// Pitfall 3: Date Mutation

let date1 = new Date();

let date2 = date1; // Reference, not copy!

date2.setFullYear(2026);

console.log(date1.getFullYear()); // 2026! date1 changed too

// CONCLUSION