Allow arbitrary and duplicate Save names.

This is done by replacing all illegal file name characters with `-`. Unicode is still preserved because it doesn't seem to be a problem for modern file systems.
The idea of file name encoding/decoding is discarded, instead the name is just stored in the zon
fixes #606

src/gui/windows/save_creation.zig

@@ -44,16 +44,48 @@ fn createWorld(_: usize) void {
 	};
 }
 
+fn findValidFolderName(allocator: NeverFailingAllocator, name: []const u8) []const u8 {
+	// Remove illegal ASCII characters:
+	const escapedName = main.stackAllocator.alloc(u8, name.len);
+	defer main.stackAllocator.free(escapedName);
+	for(name, 0..) |char, i| {
+		escapedName[i] = switch(char) {
+			'a'...'z',
+			'A'...'Z',
+			'0'...'9',
+			'_',
+			'-',
+			'.',
+			' ' => char,
+			128...255 => char,
+			else => '-',
+		};
+	}
+
+	// Avoid duplicates:
+	var resultName = main.stackAllocator.dupe(u8, escapedName);
+	defer main.stackAllocator.free(resultName);
+	var i: usize = 0;
+	while(true) {
+		const resultPath = std.fmt.allocPrint(main.stackAllocator.allocator, "saves/{s}", .{resultName}) catch unreachable;
+		defer main.stackAllocator.free(resultPath);
+
+		var dir = std.fs.cwd().openDir(resultPath, .{}) catch break;
+		dir.close();
+
+		main.stackAllocator.free(resultName);
+		resultName = std.fmt.allocPrint(main.stackAllocator.allocator, "{s}_{}", .{escapedName, i}) catch unreachable;
+		i += 1;
+	}
+	return allocator.dupe(u8, resultName);
+}
+
 fn flawedCreateWorld() !void {
 	const worldName = textInput.currentString.items;
-	const worldPath = worldName; // TODO: Make sure that only valid file name characters are used, and add a check to allow different worlds of the same name.
+	const worldPath = findValidFolderName(main.stackAllocator, worldName);
+	defer main.stackAllocator.free(worldPath);
 	const saveFolder = std.fmt.allocPrint(main.stackAllocator.allocator, "saves/{s}", .{worldPath}) catch unreachable;
 	defer main.stackAllocator.free(saveFolder);
-	if(std.fs.cwd().openDir(saveFolder, .{})) |_dir| {
-		var dir = _dir;
-		dir.close();
-		return error.AlreadyExists;
-	} else |_| {}
 	try main.files.makeDir(saveFolder);
 	{
 		const generatorSettingsPath = std.fmt.allocPrint(main.stackAllocator.allocator, "saves/{s}/generatorSettings.zig.zon", .{worldPath}) catch unreachable;

src/gui/windows/save_selection.zig

@@ -94,33 +94,6 @@ fn openFolder(index: usize) void {
 	main.files.openDirInWindow(path);
 }
 
-fn parseEscapedFolderName(allocator: NeverFailingAllocator, name: []const u8) []const u8 {
-	var result = main.List(u8).init(allocator);
-	defer result.deinit();
-	var i: u32 = 0;
-	while(i < name.len) : (i += 1) {
-		if(name[i] == '_') {
-			var val: u21 = 0;
-			for(0..4) |_| {
-				i += 1;
-				if(i < name.len) {
-					val = val*16 + switch(name[i]) {
-						'0'...'9' => name[i] - '0',
-						'a'...'f' => name[i] - 'a' + 10,
-						'A'...'F' => name[i] - 'A' + 10,
-						else => 0,
-					};
-				}
-			}
-			var buf: [4]u8 = undefined;
-			result.appendSlice(buf[0 .. std.unicode.utf8Encode(val, &buf) catch 0]); // TODO: Change this to full unicode rather than using this broken utf-16 converter.
-		} else {
-			result.append(name[i]);
-		}
-	}
-	return result.toOwnedSlice();
-}
-
 pub fn update() void {
 	if(needsUpdate) {
 		needsUpdate = false;
@@ -157,13 +130,10 @@ pub fn onOpen() void {
 				};
 				defer worldInfo.deinit(main.stackAllocator);
 
-				const decodedName = parseEscapedFolderName(main.stackAllocator, entry.name);
-				defer main.stackAllocator.free(decodedName);
-
 				worldList.append(main.globalAllocator, .{
 					.fileName = main.globalAllocator.dupe(u8, entry.name),
 					.lastUsedTime = worldInfo.get(i64, "lastUsedTime", 0),
-					.name = main.globalAllocator.dupe(u8, worldInfo.get([]const u8, "", decodedName)),
+					.name = main.globalAllocator.dupe(u8, worldInfo.get([]const u8, "name", entry.name)),
 				});
 			}
 		}