rwc-iq-29-02-24

main.go

package main

import (
	"fmt"
	"log"
	"strconv"
	"strings"
)

var daysInMonth = make(map[string]int)
var monthOfYear = make(map[string]int)
var indexedMonth = make(map[int]string)
var leapYears = "2000, 2004, 2008, 2012, 2016, 2020, 2024, 2028, 2032, 2036, 2040, 2044, and 2048"

func main() {
	daysInMonth["Jan"] = 31
	daysInMonth["Feb"] = 28
	daysInMonth["Mar"] = 31
	daysInMonth["Apr"] = 30
	daysInMonth["May"] = 31
	daysInMonth["Jun"] = 30
	daysInMonth["Jul"] = 31
	daysInMonth["Aug"] = 31
	daysInMonth["Sep"] = 30
	daysInMonth["Oct"] = 31
	daysInMonth["Nov"] = 30
	daysInMonth["Dec"] = 31

	monthOfYear["Jan"] = 1
	monthOfYear["Feb"] = 2
	monthOfYear["Mar"] = 3
	monthOfYear["Apr"] = 4
	monthOfYear["May"] = 5
	monthOfYear["Jun"] = 6
	monthOfYear["Jul"] = 7
	monthOfYear["Aug"] = 8
	monthOfYear["Sep"] = 9
	monthOfYear["Oct"] = 10
	monthOfYear["Nov"] = 11
	monthOfYear["Dec"] = 12

	indexedMonth[1] = "Jan"
	indexedMonth[2] = "Feb"
	indexedMonth[3] = "Mar"
	indexedMonth[4] = "Apr"
	indexedMonth[5] = "May"
	indexedMonth[6] = "Jun"
	indexedMonth[7] = "Jul"
	indexedMonth[8] = "Aug"
	indexedMonth[9] = "Sep"
	indexedMonth[10] = "Oct"
	indexedMonth[11] = "Nov"
	indexedMonth[12] = "Dec"

	daysBetween("Feb 29, 2020", "Oct 31, 2024")
}

func daysBetween(first, second string) {

	fMonth, fDate, fYear := splitDate(first)
	sMonth, sDate, sYear := splitDate(second)

	var daysBetweenDates int

	if strings.Contains(leapYears, fmt.Sprint(fYear)) {
		daysBetweenDates++
	}
	if strings.Contains(leapYears, fmt.Sprint(sYear)) {
		daysBetweenDates++
	}

	if fMonth == sMonth && fYear == sYear {
		daysBetweenDates = sDate - fDate
	} else if fMonth != sMonth && fYear == sYear {
		days := calcDiffdaysInMonths(fMonth, sMonth, fDate, sDate)
		daysBetweenDates = daysBetweenDates + days
	} else {
		days := calcDiffdaysInYears(fYear, sYear, fDate, sDate, fMonth, sMonth)
		daysBetweenDates = daysBetweenDates + days
	}

	fmt.Println(daysBetweenDates)
}

func calcDiffdaysInMonths(fMonth, sMonth string, fDate, sDate int) int {

	fMonthOfYear := monthOfYear[fMonth]

	sMonthOfYear := monthOfYear[sMonth]

	var days int

	for i := fMonthOfYear; i <= sMonthOfYear; i++ {
		mStr := getMonthStr(i)
		if i == fMonthOfYear {
			daysInMonth := daysInMonth[mStr]
			if fDate > 1 {
				daysLeftInMonth := daysInMonth - fDate
				days = days + daysLeftInMonth
			} else {
				days = days + daysInMonth
			}
			continue
		}
		if i > fMonthOfYear && i < sMonthOfYear {
			daysInMonth := daysInMonth[mStr]
			days = days + daysInMonth
		}
		if i == sMonthOfYear {
			days = days + sDate
		}
	}

	return days
}

func getMonthStr(i int) (month string) {
	m := indexedMonth[i]
	return m
}

func calcDiffdaysInYears(fYear, sYear, fDate, sDate int, fMonth, sMonth string) int {
	var days int
	for i := fYear; i <= sYear; i++ {
		if i == fYear {
			daysInYear := calcDiffdaysInMonths(fMonth, "Dec", fDate, 31)
			days = days + daysInYear
		} else if i == sYear {
			daysInYear := daysFromNY(sMonth, sDate)
			days = days + daysInYear
		} else {
			days = days + 365
		}
	}

	return days
}

func daysFromNY(sMonth string, sDate int) int {
	var days int
	last := monthOfYear[sMonth]
	for i := 1; i <= last; i++ {
		m := indexedMonth[i]
		if i < last {
			daysInMonth := daysInMonth[m]
			days = days + daysInMonth
		}
		if i == last {
			days = days + sDate
		}
	}

	return days
}

func splitDate(str string) (month string, date, year int) {
	slice := strings.Split(str, ",")
	monthDate := strings.Split(slice[0], " ")
	m := monthDate[0]
	d := monthDate[1]
	y := strings.Trim(slice[1], " ")

	dInt, err := strconv.Atoi(d)
	if err != nil {
		log.Fatal("err convering date to number", err)
	}
	yInt, err := strconv.Atoi(y)
	if err != nil {
		log.Fatal("err convering year to number", err)
	}
	return m, dInt, yInt
}