using TwitchLib.Client.Models;

namespace TTSMe;

public abstract class TtsMeCommand {
	private const string UsageMessage = "Usage: !ttsme <help|get|set [voice]|randomize|optout>.";
	public const bool VERBOSE = Bot.VERBOSE || false;
	private static Voices voices => Voices.Instance();

	private abstract class Messages {
		public static string VoiceSet(string username) => $"ttsme voice for '{username}' is '{Voices.Instance().GetVoice(username) ?? "none"}'";
		public static string InvalidVoice(string voice) => $"Invalid voice '{voice}'. Valid voices are: {string.Join(", ", Voices.Instance().ValidVoices)}.";
	}
	
	
	public static string? ProcessVoiceChange(ChatMessage chatMessage) {
		string username = chatMessage.Username;
		string[] args = chatMessage.Message.Split(' ');
		if (args[0] != "!ttsme") return null;
		if (args.Length is 1 or > 3) return UsageMessage;
		string action = args[1];
		string voice = args[^1];
		
		switch (action) {
			case "help": return UsageMessage;
			
			case "get" when args.Length == 2: return Messages.VoiceSet(username);
			case "get" when args.Length == 3 && username == chatMessage.Channel: return Messages.VoiceSet(voice);
			
			case "randomise" or "randomize": voices.SetRandomVoice(username); return $"ttsme voice for '{username}' has been {action}d and is now '{voices.GetVoice(username)}'.";
			
			case "set" when args.Length != 3: return Messages.InvalidVoice("NULL");
			case "set" when !voices.IsValidVoice(voice): return Messages.InvalidVoice(voice);
			case "set" when voices.IsVoice(username, voice): return $"ttsme voice for '{username}' is already set to '{voice}'.";
			case "set": voices.SetVoice(username, voice); return $"Changing ttsme for {username} to '{voice}'";
			
			// TODO: Get OptOut working so that it doesn't opt you back in when next chatting
			case "optout": voices.RemoveVoice(username); return $"Opting {username} out of ttsme, their voice will no longer be heard by the masses (and me!)";
			
			default: return UsageMessage;
		}
	}
}