JBG's Amsterdam Life in C

gantt.c

#define _XOPEN_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <math.h>

struct Task {
	char start[8];
	char end[8];
	char name[20];
	int fail;
};

void print_task(char *name, int len, int offset, int fail) {
	printf("%20s |", name);

	for(int i = 0; i < offset/2; i++) {
		printf(" ");
	}
	for(int i = 0; i < len/2; i++) {
		if(fail)
			printf("x");
		else
			printf("#");
	}
	printf("\n");
}

void print_header(int sm, int sy, int em, int ey) {
	int c = 0;
	int im = sm;
	int iy = sy;

	printf("%20s |", "");
	while(iy - 2 != ey) {
		printf("%d |", iy + 1900);
  	iy++;
	}
	printf("\n");
}

int len_months(sm, sy, em, ey) {
	int c = 0;
	int im = sm;
	int iy = sy;

	while(iy != ey || em != im) {
		while((iy != ey && im < 12) || (iy == ey && em != im)) {
			c++, im++;
		}
		if(iy != ey) {
			im = 0;
			iy++;
		}
	}
	return c;
}

void parse_dates(struct Task t, struct tm *s, struct tm *e) {
	if(strptime(t.start, "%b %Y", s) == NULL) {
		fprintf(stderr, "Error: Start time parse failed for %s", t.name);
		exit(1);
	}
	if(strptime(t.end, "%b %Y", e) == NULL) {
		fprintf(stderr, "Error: End time parse failed for %s", t.name);
		exit(1);
	}
}

int main(int argc, char **argv) {
	
	struct Task tasks[] = {
		{"Sep 2009", "May 2011", "Whatser", 1},
		{"Feb 2011", "Apr 2017", "Hackers & Founders", 0},
		{"Jul 2011", "Apr 2017", "HIP*T", 0},
		{"Aug 2011", "Jul 2013", "Ideedock", 1},
		{"Dec 2011", "Jan 2017", "HearUsHere", 0},
		{"Mar 2013", "Apr 2017", "H&F Building", 0},
		{"Jul 2013", "Apr 2017", "Hackers & Designers", 0},
		{"Dec 2013", "Jan 2016", "DuoDisco", 0},
		{"Jan 2015", "Mar 2016", "Verifeye", 0},
		{"Aug 2014", "Jul 2016", "Curious Monkeys", 1},
		{"Sep 2015", "Sep 2016", "BLACK", 1}
	};

	int num_tasks = sizeof(tasks)/sizeof(tasks[0]);
	struct Task l = tasks[num_tasks - 1];

	struct tm fs;
	struct tm ls;
	struct tm le;

	if(strptime("Jan 2009", "%b %Y", &fs) == NULL) {
		fprintf(stderr, "Error: Start time parse failed.");
		exit(1);
	}
	parse_dates(l, &ls, &le);

  	print_header(fs.tm_mon, fs.tm_year, le.tm_mon, le.tm_year);

	for(int i = 0; i < num_tasks; i++) {
		struct Task t = tasks[i];
		struct tm st;
		struct tm et;
		parse_dates(t, &st, &et);

		int task_len = len_months(
			st.tm_mon, st.tm_year,
			et.tm_mon, et.tm_year);

		int offset = len_months(
			fs.tm_mon, fs.tm_year,
			st.tm_mon, st.tm_year);

		print_task(t.name, task_len, offset, t.fail);

	}
}