JalaliDate.js

// jalali date
JalaliDate = {
  month_names: ["فروردین", "اردیبهشت", "خرداد", "تیر", "مرداد", "شهریور", "مهر", "آبان", "آذر", "دی", "بهمن", "اسفند"],
  g_days_in_month: [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31],
  j_days_in_month: [31, 31, 31, 31, 31, 31, 30, 30, 30, 30, 30, 29]
};
JalaliDate.jalaliToGregorian = function(j_y, j_m, j_d) {
  j_y = parseInt(j_y);
  j_m = parseInt(j_m);
  j_d = parseInt(j_d);
  var jy = j_y - 979;
  var jm = j_m - 1;
  var jd = j_d - 1;
  var j_day_no = 365 * jy + parseInt(jy / 33) * 8 + parseInt((jy % 33 + 3) / 4);
  for (var i = 0; i < jm; ++i) j_day_no += JalaliDate.j_days_in_month[i];
  j_day_no += jd;
  var g_day_no = j_day_no + 79;
  var gy = 1600 + 400 * parseInt(g_day_no / 146097);
  g_day_no = g_day_no % 146097;
  var leap = true;
  if (g_day_no >= 36525) {
    g_day_no--;
    gy += 100 * parseInt(g_day_no / 36524);
    g_day_no = g_day_no % 36524;
    if (g_day_no >= 365)
      g_day_no++;
    else
      leap = false;
  }
  gy += 4 * parseInt(g_day_no / 1461);
  g_day_no %= 1461;
  if (g_day_no >= 366) {
    leap = false;
    g_day_no--;
    gy += parseInt(g_day_no / 365);
    g_day_no = g_day_no % 365;
  }
  for (var i = 0; g_day_no >= JalaliDate.g_days_in_month[i] + (i == 1 && leap); i++)
    g_day_no -= JalaliDate.g_days_in_month[i] + (i == 1 && leap);
  var gm = i + 1;
  var gd = g_day_no + 1;
  return [gy, gm, gd];
}
JalaliDate.checkDate = function(j_y, j_m, j_d) {
  return !(j_y < 0 || j_y > 32767 || j_m < 1 || j_m > 12 || j_d < 1 || j_d > (JalaliDate.j_days_in_month[j_m - 1] + (j_m == 12 && !((j_y - 979) % 33 % 4))));
}
JalaliDate.gregorianToJalali = function(g_y, g_m, g_d) {
  g_y = parseInt(g_y);
  g_m = parseInt(g_m);
  g_d = parseInt(g_d);
  var gy = g_y - 1600;
  var gm = g_m - 1;
  var gd = g_d - 1;
  var g_day_no = 365 * gy + parseInt((gy + 3) / 4) - parseInt((gy + 99) / 100) + parseInt((gy + 399) / 400);
  for (var i = 0; i < gm; ++i)
    g_day_no += JalaliDate.g_days_in_month[i];
  if (gm > 1 && ((gy % 4 == 0 && gy % 100 != 0) || (gy % 400 == 0)))
  ++g_day_no;
  g_day_no += gd;
  var j_day_no = g_day_no - 79;
  var j_np = parseInt(j_day_no / 12053);
  j_day_no %= 12053;
  var jy = 979 + 33 * j_np + 4 * parseInt(j_day_no / 1461);
  j_day_no %= 1461;
  if (j_day_no >= 366) {
    jy += parseInt((j_day_no - 1) / 365);
    j_day_no = (j_day_no - 1) % 365;
  }
  for (var i = 0; i < 11 && j_day_no >= JalaliDate.j_days_in_month[i]; ++i) {
    j_day_no -= JalaliDate.j_days_in_month[i];
  }
  var jm = i + 1;
  var jd = j_day_no + 1;
  return [jy, jm, jd];
}
Date.prototype.setJalaliFullYear = function(y, m, d) {
  var gd = this.getDate();
  var gm = this.getMonth();
  var gy = this.getFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  if (y < 100) y += 1300;
  j[0] = y;
  if (m != undefined) {
    if (m > 11) {
      j[0] += Math.floor(m / 12);
      m = m % 12;
    }
    j[1] = m + 1;
  }
  if (d != undefined) j[2] = d;
  var g = JalaliDate.jalaliToGregorian(j[0], j[1], j[2]);
  return this.setFullYear(g[0], g[1] - 1, g[2]);
}
Date.prototype.setJalaliMonth = function(m, d) {
  var gd = this.getDate();
  var gm = this.getMonth();
  var gy = this.getFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  if (m > 11) {
    j[0] += Math.floor(m / 12);
    m = m % 12;
  }
  j[1] = m + 1;
  if (d != undefined) j[2] = d;
  var g = JalaliDate.jalaliToGregorian(j[0], j[1], j[2]);
  return this.setFullYear(g[0], g[1] - 1, g[2]);
}
Date.prototype.setJalaliDate = function(d) {
  var gd = this.getDate();
  var gm = this.getMonth();
  var gy = this.getFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  j[2] = d;
  var g = JalaliDate.jalaliToGregorian(j[0], j[1], j[2]);
  return this.setFullYear(g[0], g[1] - 1, g[2]);
}
Date.prototype.getJalaliFullYear = function() {
  var gd = this.getDate();
  var gm = this.getMonth();
  var gy = this.getFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  return j[0];
}
Date.prototype.getJalaliMonth = function() {
  var gd = this.getDate();
  var gm = this.getMonth();
  var gy = this.getFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  return j[1] - 1;
}
Date.prototype.getJalaliDate = function() {
  var gd = this.getDate();
  var gm = this.getMonth();
  var gy = this.getFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  return j[2];
}
Date.prototype.getJalaliDay = function() {
  var day = this.getDay();
  day = (day + 1) % 7;
  return day;
}
Date.prototype.setJalaliUTCFullYear = function(y, m, d) {
  var gd = this.getUTCDate();
  var gm = this.getUTCMonth();
  var gy = this.getUTCFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  if (y < 100) y += 1300;
  j[0] = y;
  if (m != undefined) {
    if (m > 11) {
      j[0] += Math.floor(m / 12);
      m = m % 12;
    }
    j[1] = m + 1;
  }
  if (d != undefined) j[2] = d;
  var g = JalaliDate.jalaliToGregorian(j[0], j[1], j[2]);
  return this.setUTCFullYear(g[0], g[1] - 1, g[2]);
}
Date.prototype.setJalaliUTCMonth = function(m, d) {
  var gd = this.getUTCDate();
  var gm = this.getUTCMonth();
  var gy = this.getUTCFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  if (m > 11) {
    j[0] += Math.floor(m / 12);
    m = m % 12;
  }
  j[1] = m + 1;
  if (d != undefined) j[2] = d;
  var g = JalaliDate.jalaliToGregorian(j[0], j[1], j[2]);
  return this.setUTCFullYear(g[0], g[1] - 1, g[2]);
}
Date.prototype.setJalaliUTCDate = function(d) {
  var gd = this.getUTCDate();
  var gm = this.getUTCMonth();
  var gy = this.getUTCFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  j[2] = d;
  var g = JalaliDate.jalaliToGregorian(j[0], j[1], j[2]);
  return this.setUTCFullYear(g[0], g[1] - 1, g[2]);
}
Date.prototype.getJalaliUTCFullYear = function() {
  var gd = this.getUTCDate();
  var gm = this.getUTCMonth();
  var gy = this.getUTCFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  return j[0];
}
Date.prototype.getJalaliUTCMonth = function() {
  var gd = this.getUTCDate();
  var gm = this.getUTCMonth();
  var gy = this.getUTCFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  return j[1] - 1;
}
Date.prototype.getJalaliUTCDate = function() {
  var gd = this.getUTCDate();
  var gm = this.getUTCMonth();
  var gy = this.getUTCFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  return j[2];
}
Date.prototype.getJalaliUTCDay = function() {
  var day = this.getUTCDay();
  day = (day + 1) % 7;
  return day;
}
Date.prototype.getJalaliTime = function() {
  var gd = this.getUTCDate();
  var gm = this.getUTCMonth();
  var gy = this.getUTCFullYear();
  var j = JalaliDate.gregorianToJalali(gy, gm + 1, gd);
  return {
    year: j[0],
    month: j[1],
    day: j[2]
  };
}
JalaliDate.dateToJalali = function(date) {
  var gd = date.getUTCDate();
  var gm = date.getUTCMonth();
  var gy = date.getUTCFullYear();
  return JalaliDate.gregorianToJalali(gy, gm + 1, gd);
}
Date.prototype.getJalaliMonthName = function() {
  return JalaliDate.month_names[this.getJalaliMonth()];
}

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