From b9925f923f344b41e057ac23df05a1738d34dfe1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Frank=20Bo=C3=ABs?= <fboes@3960.org>
Date: Mon, 13 May 2019 18:56:21 +0200
Subject: [PATCH] Interpret date `YYYY/MM/DD` prepended to METAR string

---
 CHANGELOG.md                                |  1 +
 src/MetarParserSimple/MetarParserSimple.cpp | 52 +++++++++++++++++----
 src/MetarParserSimple/MetarParserSimple.h   |  8 +++-
 3 files changed, 51 insertions(+), 10 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 931dcf5..0ba4ece 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,7 @@ Change log
 ==========
 
 * 🎁 Add sample ICAO airport codes to combobox
+* 🎁 Interpret date `YYYY/MM/DD` prepended to METAR string
 
 1.2.2
 -----
diff --git a/src/MetarParserSimple/MetarParserSimple.cpp b/src/MetarParserSimple/MetarParserSimple.cpp
index 6cc368f..3341c49 100644
--- a/src/MetarParserSimple/MetarParserSimple.cpp
+++ b/src/MetarParserSimple/MetarParserSimple.cpp
@@ -6,6 +6,25 @@
 #include <iterator>
 #include <regex>
 
+void MetarParserSimple::initializeDate()
+{
+	if (this->observed.year != 1970) {
+		return;
+	}
+
+	time_t rawtime;
+	struct tm ptm;
+
+	time(&rawtime);
+
+	gmtime_s(&ptm, &rawtime);
+	this->observed.year = ptm.tm_year + 1900;
+	this->observed.month = ptm.tm_mon + 1;
+	this->observed.day = ptm.tm_mday;
+	this->observed.hours = ptm.tm_hour;
+	this->observed.minutes = ptm.tm_min;
+}
+
 void MetarParserSimple::fixTimeDate()
 {
 	// This is a naive approach, but it does the job
@@ -124,6 +143,14 @@ bool MetarParserSimple::convert(std::string metarString)
 				strcpy_s(this->icao, 8, metarPart.c_str());
 				parsingMode = 1;
 			}
+			// Non-standard date prepended, parsing it anyway
+			else if (std::regex_match(metarPart, match, std::regex("([1-2]\\d{3})\\D([0-1]\\d)\\D([0-3]\\d)"))) {
+				this->setDate2(
+					std::stoi(match[1].str()),
+					std::stoi(match[2].str()),
+					std::stoi(match[3].str())
+				);
+			}
 			break;
 		case 1:
 			// Observed Date
@@ -309,17 +336,24 @@ double MetarParserSimple::getHumidity()
 
 void MetarParserSimple::setDate(short day, short hours, short minutes)
 {
-	time_t rawtime;
-	struct tm ptm;
+	this->initializeDate();
 
-	time(&rawtime);
+	// Day may be in preceeding month
+	if (day > this->observed.day) {
+		this->observed.month -= 1;
+	}
+	this->observed.day = day;
+	this->observed.hours = hours;
+	this->observed.minutes = minutes;
+	this->fixTimeDate();
+}
 
-	gmtime_s(&ptm, &rawtime);
-	this->observed.year = ptm.tm_year + 1900;
-	this->observed.month = ptm.tm_mon + 1;
-	this->observed.day = (day >= 0) ? day : ptm.tm_mday;
-	this->observed.hours = (hours >= 0) ? hours : ptm.tm_hour;
-	this->observed.minutes = (minutes >= 0) ? minutes : ptm.tm_min;
+void MetarParserSimple::setDate2(int year, short month, short day)
+{
+	this->initializeDate();
+	this->observed.year = year;
+	this->observed.month = month;
+	this->observed.day = day;
 	this->fixTimeDate();
 }
 
diff --git a/src/MetarParserSimple/MetarParserSimple.h b/src/MetarParserSimple/MetarParserSimple.h
index 4518551..74135e0 100644
--- a/src/MetarParserSimple/MetarParserSimple.h
+++ b/src/MetarParserSimple/MetarParserSimple.h
@@ -18,6 +18,9 @@
 class METARPARSERSIMPLE_API MetarParserSimple
 {
 private:
+	// Set date to current date
+	void initializeDate();
+
 	// Keep time and date in bounds
 	void fixTimeDate();
 
@@ -113,9 +116,12 @@ class METARPARSERSIMPLE_API MetarParserSimple
 	// Get humidity in percent 0..1
 	double getHumidity();
 
-	// Set date / time to current UTC time, but allow for modification.
+	// Set date / time, but allow for modification.
 	void setDate(short day = -1, short hours = -1, short minutes = -1);
 
+	// Set date, but allow for modification.
+	void setDate2(int year, short month, short day);
+
 	// Change parsed time by hoursOffset.
 	void addHours(int hoursOffset);