progtest3.c

#include <stdio.h> 
#include <assert.h> 
#define INVALID_DATE(-1)

int isLeapYear(int y) //0 ~ no; 1 ~ yes
{
    if (y % 4000 == 0) {
        return 0;
    } else {
        if (y % 400 == 0) {
            return 1;
        } else {
            if (y % 100 == 0) {
                return 0;
            } else {
                if (y % 4 == 0) {
                    return 1;
                } else {
                    return 0;
                }
            }
        }
    }
}

int daysSince2000(int d, int m, int y) //means <1.1.2000 ; dd.mm.yyyy>
{
    int a = (y / 4) - (y / 100) + (y / 400) - (y / 4000); //number of leap years
    a = (a * 366) + ((y - a) * 365) - 730484; //days to 1.1.y

    int b = 0;
    if (isLeapYear(y) == 1) {
        b = 1;
    }

    switch (m) {
    case 1: //Jan
        a = a + d;
        break;
    case 2: //Feb
        a = a + 31 + d;
        break;
    case 3: //Mar
        a = a + 59 + d + b;
        break;
    case 4: //Apr
        a = a + 90 + d + b;
        break;
    case 5: //May
        a = a + 120 + d + b;
        break;
    case 6: //Jun
        a = a + 151 + d + b;
        break;
    case 7: //Jul
        a = a + 181 + d + b;
        break;
    case 8: //Aug
        a = a + 212 + d + b;
        break;
    case 9: //Sep
        a = a + 243 + d + b;
        break;
    case 10: //Oct
        a = a + 273 + d + b;
        break;
    case 11: //Nov
        a = a + 304 + d + b;
        break;
    case 12: //Dec
        a = a + 334 + d + b;
        break;
    }

    if (y == 2000) {
        a--;
    }

    return a - 1;
}

long long int SecondsSinceRef(int y, int m, int d, int hod, int min, int sec) {
    long long time = daysSince2000(d, m, y);
    long long ref_time = (197 * 86400) + (13 * 3600) + (55 * 60) + 12;
    time = (time * 86400) + sec + (min * 60) + (hod * 3600) - ref_time;
    return time;
}

int inputCheck(int y, int m, int d) {
    if (y < 2000 || m < 1 || m > 12 || d > 31) {
        return (-1);
    }

    if ((m == 1 || m == 3 || m == 5 || m == 7 || m == 8 || m == 10 || m == 12) && d > 31) {
        return (-1);
    }
    if ((m == 4 || m == 6 || m == 9 || m == 11) && d > 30) {
        return (-1);
    }
    if (m == 2) {
        if (isLeapYear(y) == 1 && d > 29) {
            return (-1);
        }
        if (isLeapYear(y) == 0 && d > 28) {
            return (-1);
        }
    }
    return 1;
}

int isFullMoon(int y, int m, int d) //přidat fci pro začátek roku 2000!!!!
{
    if (inputCheck(y, m, d) == (-1)) {
        return (-1);
    }

    if (y == 2000 && m == 7 && d == 16) {
        return 1;
    }

    int a = SecondsSinceRef(y, m, d, 0, 0, 0) / 2551443;
    int b = SecondsSinceRef(y, m, d, 23, 59, 59) / 2551443;

    return b - a;
}

int prevFullMoon(int y, int m, int d,
    int * prevY, int * prevM, int * prevD) //VSTUPYYYYYYY!!!!!
{
    if (inputCheck(y, m, d) == (-1)) {
        return (-1);
    }
    long long int a = SecondsSinceRef(y, m, d, 0, 0, 0);

    a = (a % 2551443) / 86400 + 1;

    int month_changed = 0;

    int day = d;
    int month = m;
    int year = y;

    day = d - a;

    if (day < 1) {
        if (month == 3) {
            if (isLeapYear(year) == 1) {
                day = day + 29;
                month--;
            }

            if (isLeapYear(year) == 0) {
                day = day + 28;
                month--;
            }
        }

        if (month == 1) {
            day = day + 31;
            month = 12;
            year--;
            month_changed = 1;
        }

        if ((month == 5 || month == 7 || month == 10 || month == 12) && month_changed == 0) {
            day = day + 30;
            month--;
            month_changed = 1;
        }

        if (month == 2) {
            day = day + 31;
            month--;
        }

        if ((month == 4 || month == 6 || month == 8 || month == 9 || month == 11) && month_changed == 0) {
            day = day + 31;
            month--;
        }

    }

    * prevY = year;
    * prevM = month;
    * prevD = day;

    if (y == 2000) {
        if ((m == 7 && d <= 16) || (m == 6 && d > 16)) {
            * prevM = 6;
            * prevD = 16;
        }
        if ((m == 6 && d <= 16) || (m == 5 && d > 18)) {
            * prevM = 5;
            * prevD = 18;
        }
        if ((m == 5 && d <= 18) || (m == 4 && d > 18)) {
            * prevM = 4;
            * prevD = 18;
        }
        if ((m == 4 && d <= 18) || (m == 3 && d > 20)) {
            * prevM = 3;
            * prevD = 20;
        }
        if ((m == 3 && d <= 20) || (m == 2 && d > 19)) {
            * prevM = 2;
            * prevD = 19;
        }
        if ((m == 2 && d <= 19) || (m == 1 && d > 21)) {
            * prevM = 1;
            * prevD = 21;
        }
        if (m == 1 && d <= 21) {
            * prevM = 12;
            * prevD = 22;
            * prevY = 1999;
        }
    }

    return 1;
}

int nextFullMoon(int y, int m, int d,
    int * nextY, int * nextM, int * nextD) {
    if (inputCheck(y, m, d) == (-1)) {
        return (-1);
    }
    long long int b = SecondsSinceRef(y, m, d, 23, 59, 59);
    b = (2551443 - (b % 2551443)) / 86400 + 1;

    int day = d;
    int month = m;
    int year = y;

    day = d + b;

    if (day >= 29) {
        if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10) {
            if (day > 31) {
                day = day - 31;
                month++;
            }
        }

        if (month == 4 || month == 6 || month == 9 || month == 11) {
            if (day > 30) {
                day = day - 30;
                month++;
            }
        }

        if (month == 2) {
            if (day > 29 && isLeapYear(year) == 1) {
                day = day - 29;
                month++;
            }

            if (day > 28 && isLeapYear(year) == 0) {
                day = day - 28;
                month++;
            }
        }

        if (month == 12) {
            if (day > 31) {
                day = day - 31;
                month = 1;
                year++;
            }
        }
    }

    if (day == 51 && month == 0) {
        day = 21;
        month = 1;
    }

    * nextY = year;
    * nextM = month;
    * nextD = day;

    if (y == 2000) {
        if ((m == 7 && d < 16) || (m == 6 && d >= 16)) {
            * nextM = 7;
            * nextD = 16;
        }
        if ((m == 6 && d < 16) || (m == 5 && d >= 18)) {
            * nextM = 6;
            * nextD = 16;
        }
        if ((m == 5 && d < 18) || (m == 4 && d >= 18)) {
            * nextM = 5;
            * nextD = 18;
        }
        if ((m == 4 && d < 18) || (m == 3 && d >= 20)) {
            * nextM = 4;
            * nextD = 18;
        }
        if ((m == 3 && d < 20) || (m == 2 && d >= 19)) {
            * nextM = 3;
            * nextD = 20;
        }
        if ((m == 2 && d < 19) || (m == 1 && d >= 21)) {
            * nextM = 2;
            * nextD = 19;
        }
        if (m == 1 && d < 21) {
            * nextM = 1;
            * nextD = 21;
        }
    }

    return 1;
}