feat: load optional XDG TOML configuration with session overrides

Sources/CLI/PlayerCommand.swift

@@ -2,12 +2,12 @@ import Foundation
 
 enum PlayerCommand {
     case help
-    case launch(URL?, newInstance: Bool)
+    case launch(URL?, newInstance: Bool, noConfig: Bool)
 
     static let usage = """
-    Usage: terebi [--new-instance] [FILE | YOUTUBE_URL]
-           terebi [--new-instance] --url YOUTUBE_URL
-           terebi [--new-instance] -- FILE
+    Usage: terebi [--new-instance] [--no-config] [FILE | YOUTUBE_URL]
+           terebi [--new-instance] [--no-config] --url YOUTUBE_URL
+           terebi [--new-instance] [--no-config] -- FILE
            terebi --help
 
     Open one local media file or YouTube video and start playback, resuming saved
@@ -15,6 +15,7 @@ enum PlayerCommand {
     Quote paths and URLs containing spaces or shell metacharacters.
 
       --new-instance Launch a separate player, leaving existing playback untouched.
+      --no-config    Use built-in settings instead of config.toml on a fresh launch.
       --url URL      Open a YouTube video URL.
       --             Treat the following argument as a filename, even with a leading '-'.
       -h, --help     Show this help without launching the player.
@@ -26,13 +27,23 @@ enum PlayerCommand {
 
     static func parse(_ arguments: [String], directory: URL = URL(fileURLWithPath: FileManager.default.currentDirectoryPath, isDirectory: true)) throws -> PlayerCommand {
         var inputs = arguments
-        let newInstance = inputs.first == "--new-instance"
-        if newInstance { inputs.removeFirst() }
-        if inputs.isEmpty { return .launch(nil, newInstance: newInstance) }
+        var newInstance = false
+        var noConfig = false
+        while let option = inputs.first, option == "--new-instance" || option == "--no-config" {
+            if option == "--new-instance" {
+                guard !newInstance else { throw ArgumentError("--new-instance may only be supplied once.") }
+                newInstance = true
+            } else {
+                guard !noConfig else { throw ArgumentError("--no-config may only be supplied once.") }
+                noConfig = true
+            }
+            inputs.removeFirst()
+        }
+        if inputs.isEmpty { return .launch(nil, newInstance: newInstance, noConfig: noConfig) }
         if inputs == ["--help"] || inputs == ["-h"] { return .help }
         if inputs.first == "--url" {
             guard inputs.count == 2 else { throw ArgumentError("--url requires exactly one YouTube URL.") }
-            return .launch(try YouTubeResolver.validateURL(inputs[1]), newInstance: newInstance)
+            return .launch(try YouTubeResolver.validateURL(inputs[1]), newInstance: newInstance, noConfig: noConfig)
         }
         let filenameOnly = inputs.first == "--"
         if filenameOnly {
@@ -52,7 +63,7 @@ enum PlayerCommand {
                 }
                 file = url
             } else {
-                return .launch(try YouTubeResolver.validateURL(input), newInstance: newInstance)
+                return .launch(try YouTubeResolver.validateURL(input), newInstance: newInstance, noConfig: noConfig)
             }
         } else {
             let base = directory.hasDirectoryPath ? directory : URL(fileURLWithPath: directory.path, isDirectory: true)
@@ -62,7 +73,7 @@ enum PlayerCommand {
               FileManager.default.isReadableFile(atPath: file.path) else {
             throw ArgumentError("File does not exist or is not a readable regular file.")
         }
-        return .launch(file.standardizedFileURL, newInstance: newInstance)
+        return .launch(file.standardizedFileURL, newInstance: newInstance, noConfig: noConfig)
     }
 
     private struct ArgumentError: LocalizedError {