the 'FORTUNE_CS_DIR' environment variable now overrides default fortune path

src/Program.cs

@@ -2,8 +2,34 @@ using System;
 using System.IO;
 using System.Security.Cryptography;
 
+//	get resource path from var or default
+string resourcePath = Environment.GetEnvironmentVariable("FORTUNE_CS_DIR");
+if(resourcePath == "" || !Directory.Exists(resourcePath))
+	resourcePath = "/usr/share/fortune-cs/";
+
+//	pull file arg if 1 argument is provided
+string file = null;
+if(args.Length == 1) {
+	file = args[0];
+	//	if the file doens't exist, see if it's in `resourcePath`
+	if(!File.Exists(file)) {
+		if(!file.EndsWith(".txt"))
+			file = file + ".txt";
+		file = resourcePath + file;
+		if(!File.Exists(file)) {
+			//	don't try to read a file that doesn't exist
+			Console.WriteLine($"fortune-cs: no file '{file}' found.");
+			return 2;
+		}
+	}
+}
+//	run merge if more than 1 argument is provided
+else if(args.Length > 0) {
+	Utilities.Merge(args);
+	return 0;
+}
+
 //	make sure fortune directory exists
-var resourcePath = "/usr/share/fortune-cs/";
 if(!Directory.Exists(resourcePath)) {
 	Console.WriteLine("fortune-cs: directory '/usr/share/fortune-cs/' does not exist");
 	return 1;
@@ -12,19 +38,17 @@ if(!Directory.Exists(resourcePath)) {
 //	pull file list
 var files = Directory.GetFiles(resourcePath, "*.txt");
 
-var prng = RandomNumberGenerator.Create();
-
-//	choose a file and line
-var file = files[RandomNumberGenerator.GetInt32(files.Length)];
+//	choose file if no arg provided
+if(file == null)
+	file = files[RandomNumberGenerator.GetInt32(files.Length)];
+//	read the file and choose a line
 var lines = File.ReadAllLines(file);
 var line = lines[RandomNumberGenerator.GetInt32(lines.Length)];
 
-prng.Dispose();
-
-//	process escape codes
+//	process line breaks
 line = line.Replace("\\n", "\n");
 
-//	write
+//	write the fortune
 Console.WriteLine(line);
 
 return 0;

src/Util.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+
+public static class Utilities {
+
+	public static void Merge(params string[] files) {
+		//	hashset to prevent duplicates
+		var members = new HashSet<string>();
+		//	iterate over all paths given
+		foreach(var file in files) {
+			//	skip nonexistent files gracefully
+			if(!File.Exists(file))
+				continue;
+			//	iterate over lines
+			var lines = File.ReadAllLines(file);
+			foreach(var line in lines) {
+				//	prevent duplicates
+				if(members.Contains(line))
+					continue;
+				members.Add(line);
+				//	emit to stdout
+				Console.WriteLine(line);
+			}
+		}
+	}
+
+}
+