Handle empty directory and invalid image extension

src/Wallpapers.cpp

@@ -2,14 +2,20 @@
 #include <algorithm>
 #include <filesystem>
 #include <iostream>
+#include <ostream>
+#include <stdexcept>
 
 Wallpapers::Wallpapers(const std::string& directoryPath) : directoryPath(directoryPath) {
 
 	for (const auto& entry : std::filesystem::directory_iterator(directoryPath)) {
+		if (!isValidPath(entry.path())) {
+			continue;
+		}
 		wallpapersPath.push_back(entry.path());
 	}
-	for (const std::string& wallpaperPath : wallpapersPath) {
+	if (wallpapersPath.size() == 0) {
-		std::cout << wallpaperPath << std::endl;
+		throw std::runtime_error("Directory '" + directoryPath + "' doesn't contain any valid wallapers\n\
+Allowed extension are .png, .jpg, .jpeg");
 	}
 	e1 = std::default_random_engine(r());
 	uniformDist = std::uniform_int_distribution<int>(0, wallpapersPath.size());
@@ -22,7 +28,21 @@ void Wallpapers::shuffle() {
 }
 
 const std::string& Wallpapers::next() {
+	if (wallpapersPathQueue.size() == 0) {
+		throw std::runtime_error("No valid wallpapers found when calling Wallpapers::next method");
+	}
 	const std::string& wallpaperPath = wallpapersPathQueue[currentWallpaperIndex];
 	currentWallpaperIndex = (currentWallpaperIndex + 1) % wallpapersPathQueue.size();
 	return wallpaperPath;
 }
+
+bool Wallpapers::isValidPath(const std::string& path) const {
+	static std::array validExtensions {"jpg", "jpeg", "png"};
+
+	for (const auto& extension : validExtensions) {
+		if (path.ends_with(extension)) {
+			return true;
+		}
+	}
+	return false;
+}

src/Wallpapers.h

@@ -1,4 +1,5 @@
 #pragma once
+#include <array>
 #include <random>
 #include <string>
 #include <vector>
@@ -14,6 +15,8 @@ class Wallpapers {
 
 	private:
 
+	bool isValidPath(const std::string& path) const;
+
 	std::string directoryPath;
 	std::vector<std::string> wallpapersPath;
 	std::vector<std::string> wallpapersPathQueue;

src/main.cpp

@@ -1,84 +1,92 @@
 #include "CliArguments.h"
 #include "Wallpapers.h"
 #include "SwaybgProcess.h"
+#include <exception>
 #include <iostream>
 #include <ostream>
 #include <string>
 
 int main(int argc, char** argv, char** envp) {
 
-	CliArguments::CliArguments arguments{
+	try {
-		argc, argv,
+		
-		{
-			{"path", {
-				.description = "The path to the directory containing the wallpapers",
-				.type = CliArguments::String,
-				.order = 0,
-				.direct = true
-			}},
-			{"output", {
-				.description = "The outputs as shown with the command `swaymsg -t get_outputs`",
-				.type = CliArguments::String,
-				.order = 1,
-				.direct = true
-			}},
-			{"interval", {
-				.aliases = {"i"},
-				.description = "Specify the interval between wallpapers in seconds",
-				.type = CliArguments::Int,
-			}},
-			{"never-random", {
-				.description = "if set, wallpapers order is based on the names of the files",
-				.type = CliArguments::Bool,
-			}},
-			{"help", {
-				.aliases = {"h"},
-				.description = "Show help",
-				.type = CliArguments::Bool,
-			}},
-		}
-	};
 
-	if (!arguments.isValid()) {
+		CliArguments::CliArguments arguments{
-		std::cout << arguments.error() << std::endl;
+			argc, argv,
-		arguments.printHelp();
+			{
+				{"path", {
+					.description = "The path to the directory containing the wallpapers",
+					.type = CliArguments::String,
+					.order = 0,
+					.direct = true
+				}},
+				{"output", {
+					.description = "The outputs as shown with the command `swaymsg -t get_outputs`",
+					.type = CliArguments::String,
+					.order = 1,
+					.direct = true
+				}},
+				{"interval", {
+					.aliases = {"i"},
+					.description = "Specify the interval between wallpapers in seconds",
+					.type = CliArguments::Int,
+				}},
+				{"never-random", {
+					.description = "if set, wallpapers order is based on the names of the files",
+					.type = CliArguments::Bool,
+				}},
+				{"help", {
+					.aliases = {"h"},
+					.description = "Show help",
+					.type = CliArguments::Bool,
+				}},
+			}
+		};
+
+		if (!arguments.isValid()) {
+			std::cout << arguments.error() << std::endl;
+			arguments.printHelp();
+			return 1;
+		}
+
+		if (arguments.exists("help")) {
+			arguments.printHelp();
+			return 0;
+		}
+
+		const std::string path = arguments.getString("path");
+		const std::string output = arguments.getString("output");
+
+		Wallpapers wallpapers(path);
+
+		if (!arguments.exists("never-random")) {
+			wallpapers.shuffle();
+		}
+
+		SwaybgProcess swayBgProcess(wallpapers.next(), output);
+		swayBgProcess.exec();
+
+		if (arguments.exists("interval")) {
+			int interval = arguments.getInt("interval");
+			while (true) {
+				sleep(interval);
+				SwaybgProcess newSwayBgProcess(wallpapers.next(), output);
+				newSwayBgProcess.exec();
+				sleep(1);
+				swayBgProcess.kill();
+				swayBgProcess = newSwayBgProcess;
+			}
+		} else {
+			char ch;
+			while (ch != 'q') {
+				ch = std::cin.get();
+			}
+		}
+
+		swayBgProcess.kill();
+		return 0;
+	} catch (std::exception& e) {
+		std::cerr << e.what() << std::endl;
 		return 1;
 	}
-
-	if (arguments.exists("help")) {
-		arguments.printHelp();
-		return 0;
-	}
-
-	const std::string path = arguments.getString("path");
-	const std::string output = arguments.getString("output");
-
-	Wallpapers wallpapers(path);
-
-	if (!arguments.exists("never-random")) {
-		wallpapers.shuffle();
-	}
-
-	SwaybgProcess swayBgProcess(wallpapers.next(), output);
-	swayBgProcess.exec();
-
-	if (arguments.exists("interval")) {
-		int interval = arguments.getInt("interval");
-		while (true) {
-			sleep(interval);
-			SwaybgProcess newSwayBgProcess(wallpapers.next(), output);
-			newSwayBgProcess.exec();
-			sleep(1);
-			swayBgProcess.kill();
-			swayBgProcess = newSwayBgProcess;
-		}
-	} else {
-		char ch;
-		while (ch != 'q') {
-			ch = std::cin.get();
-		}
-	}
-
-	swayBgProcess.kill();
-	return 0;
 }