Simplify streak calculations

common.cpp

@@ -1,4 +1,5 @@
 #include "common.h"
+#include "debug.h"
 
 #include <algorithm>
 #include <numeric>
@@ -178,49 +179,43 @@ void show_nested_histogram(const Caches& cc, std::string Cache::*ptr, std::strin
 	}
 }
 
-static bool same_day(const std::tm& a, const std::tm& b) {
-	return (a.tm_year == b.tm_year && a.tm_mon == b.tm_mon && a.tm_mday == b.tm_mday);
-}
-
-static void next_day(std::tm& a) {
-	a.tm_mday++;
-	mktime(&a);
-}
-
-int find_streak(const std::multimap<std::time_t, const Cache*>& cc, std::tm& start) {
+int find_streak(const std::multimap<std::time_t, const Cache*>& cc, std::time_t& start) {
 	int max_str = 0;
 	int cur_str = 0;
 
-	std::tm cur_tm;
-	cur_tm.tm_year = 0;
-	std::tm cur_start_tm = cur_tm;
-	start = cur_tm;
+	int cur = 0;
+	int cur_start = cur;
+	int max_start = cur;
 
 	for (auto i : cc) {
-		if (same_day(cur_tm, *std::localtime(&i.first)))
+		if (cur == i.first / 86400)
 			continue;
-		next_day(cur_tm);
-		if (same_day(cur_tm, *std::localtime(&i.first))) {
+		if (i.first / 86400 - cur == 1) {
 			cur_str++;
+			cur = i.first / 86400;
 			continue;
 		}
+
+// streak ended
+
 		if (max_str < cur_str) {
 			max_str = cur_str;
-			start = cur_start_tm;
+			max_start = cur_start;
 		}
 		cur_str = 1;
-		cur_tm = cur_start_tm = *std::localtime(&i.first);
+		cur = cur_start = i.first / 86400;
 		if (max_str == 0) {
 			max_str = 1;
-			start = cur_tm;
+			max_start = cur;
 		}
 	}
 
 	if (max_str < cur_str) {
 		max_str = cur_str;
-		start = cur_start_tm;
+		max_start = cur_start;
 	}
 
+	start = max_start * 86400; // convert back from month count to time_t
 	return max_str;
 }
 

common.h

@@ -8,7 +8,7 @@ void show_histogram(const Caches& cc, std::string Cache::*ptr, const std::string
 void show_histogram(const std::map<std::string, int>& data, const std::string& caption, bool html = 0, bool sort_by_val = 1);
 void show_nested_histogram(const Caches& cc, std::string Cache::*ptr, std::string Cache::*ptr2, const std::string& caption, bool html = 0, bool sort_by_val = 1);
 
-int find_streak(const std::multimap<std::time_t, const Cache*>& cc, std::tm& start);
+int find_streak(const std::multimap<std::time_t, const Cache*>& cc, std::time_t& start);
 
 long int get_num(char c, char* opt);
 

geostat.cpp

@@ -377,10 +377,11 @@ int main(int argc, char** argv) {
 			std::cout << i.first << ", found " << i.second << " caches<br>\n";
 		std::cout << "  </p>\n</details>\n";
 
-		std::tm streak;
+		std::time_t streak;
 		int longest_str = find_streak(sorted_caches, streak);
 		char str_tmp[20];
-		std::strftime(str_tmp, 20, "%F", &streak);
+		std::tm* str_tm = std::localtime(&streak);
+		std::strftime(str_tmp, 20, "%F", str_tm);
 		std::cout << "Longest caching streak: <span class=\"value\">" << longest_str << "</span> starting on <span class=\"value\">" << str_tmp << "</span><br>\n";
 
 		float tot_dist = 0;