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/*
* Copyright (c) 2012-2014 Christian Hansen <chansen@cpan.org>
* <https://github.com/chansen/c-dt>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "dt_core.h"
#include "dt_util.h"
#include "dt_arithmetic.h"
dt_t
dt_add_years(dt_t dt, int delta, dt_adjust_t adjust) {
int y, d;
dt_to_yd(dt, &y, &d);
if (adjust == DT_EXCESS || d < 365)
return dt_from_yd(y + delta, d);
else {
int ry = y + delta;
int diy;
diy = dt_days_in_year(ry);
if (d > diy || (adjust == DT_SNAP && d == dt_days_in_year(y)))
d = diy;
return dt_from_yd(ry, d);
}
}
dt_t
dt_add_quarters(dt_t dt, int delta, dt_adjust_t adjust) {
int y, q, d;
dt_to_yqd(dt, &y, &q, &d);
if (adjust == DT_EXCESS || d < 90)
return dt_from_yqd(y, q + delta, d);
else {
int ry = y;
int rq = q + delta;
int diq;
if (rq < 1 || rq > 4) {
ry += rq / 4;
rq %= 4;
if (rq < 1)
ry--, rq += 4;
}
diq = dt_days_in_quarter(ry, rq);
if (d > diq || (adjust == DT_SNAP && d == dt_days_in_quarter(y, q)))
d = diq;
return dt_from_yqd(ry, rq, d);
}
}
dt_t
dt_add_months(dt_t dt, int delta, dt_adjust_t adjust) {
int y, m, d;
dt_to_ymd(dt, &y, &m, &d);
if (adjust == DT_EXCESS || d < 28)
return dt_from_ymd(y, m + delta, d);
else {
int ry = y;
int rm = m + delta;
int dim;
if (rm < 1 || rm > 12) {
ry += rm / 12;
rm %= 12;
if (rm < 1)
ry--, rm += 12;
}
dim = dt_days_in_month(ry, rm);
if (d > dim || (adjust == DT_SNAP && d == dt_days_in_month(y, m)))
d = dim;
return dt_from_ymd(ry, rm, d);
}
}
void
dt_delta_yd(dt_t dt1, dt_t dt2, int *yp, int *dp) {
int y1, y2, d1, d2, ny, nd;
dt_to_yd(dt1, &y1, &d1);
dt_to_yd(dt2, &y2, &d2);
ny = y2 - y1;
nd = d2 - d1;
if (ny > 0 && nd < 0) {
ny--;
nd = dt2 - dt_add_years(dt1, ny, DT_LIMIT);
}
else if (ny < 0 && nd > 0) {
ny++;
nd -= dt_days_in_year(y2);
}
if (yp) *yp = ny;
if (dp) *dp = nd;
}
void
dt_delta_yqd(dt_t dt1, dt_t dt2, int *yp, int *qp, int *dp) {
int y1, y2, q1, q2, d1, d2, ny, nq, nd;
dt_to_yqd(dt1, &y1, &q1, &d1);
dt_to_yqd(dt2, &y2, &q2, &d2);
nq = 4 * (y2 - y1) + q2 - q1;
nd = d2 - d1;
if (nq > 0 && nd < 0) {
nq--;
nd = dt2 - dt_add_quarters(dt1, nq, DT_LIMIT);
}
else if (nq < 0 && nd > 0) {
nq++;
nd -= dt_days_in_quarter(y2, q2);
}
ny = nq / 4;
nq = nq - ny * 4;
if (qp) *yp = ny;
if (qp) *qp = nq;
if (dp) *dp = nd;
}
void
dt_delta_ymd(dt_t dt1, dt_t dt2, int *yp, int *mp, int *dp) {
int y1, y2, m1, m2, d1, d2, ny, nm, nd;
dt_to_ymd(dt1, &y1, &m1, &d1);
dt_to_ymd(dt2, &y2, &m2, &d2);
nm = 12 * (y2 - y1) + m2 - m1;
nd = d2 - d1;
if (nm > 0 && nd < 0) {
nm--;
nd = dt2 - dt_add_months(dt1, nm, DT_LIMIT);
}
else if (nm < 0 && nd > 0) {
nm++;
nd -= dt_days_in_month(y2, m2);
}
ny = nm / 12;
nm = nm - ny * 12;
if (yp) *yp = ny;
if (mp) *mp = nm;
if (dp) *dp = nd;
}
int
dt_delta_years(dt_t dt1, dt_t dt2, bool complete) {
int y1, y2, d1, d2, ny;
dt_to_yd(dt1, &y1, &d1);
dt_to_yd(dt2, &y2, &d2);
ny = y2 - y1;
if (complete) {
if (dt1 > dt2)
ny += (d2 > d1);
else
ny -= (d1 > d2);
}
return ny;
}
int
dt_delta_quarters(dt_t dt1, dt_t dt2, bool complete) {
int y1, y2, q1, q2, d1, d2, nq;
dt_to_yqd(dt1, &y1, &q1, &d1);
dt_to_yqd(dt2, &y2, &q2, &d2);
nq = 4 * (y2 - y1) + q2 - q1;
if (complete) {
if (dt1 > dt2)
nq += (d2 > d1);
else
nq -= (d1 > d2);
}
return nq;
}
int
dt_delta_months(dt_t dt1, dt_t dt2, bool complete) {
int y1, y2, m1, m2, d1, d2, nm;
dt_to_ymd(dt1, &y1, &m1, &d1);
dt_to_ymd(dt2, &y2, &m2, &d2);
nm = 12 * (y2 - y1) + m2 - m1;
if (complete) {
if (dt1 > dt2)
nm += (d2 > d1);
else
nm -= (d1 > d2);
}
return nm;
}
int
dt_delta_weeks(dt_t dt1, dt_t dt2) {
return (dt2 - dt1) / 7;
}
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