package org.telegram.telegrambots.extensions.bots.commandbot.commands.helpCommand;

import org.telegram.telegrambots.extensions.bots.commandbot.commands.IBotCommand;
import org.telegram.telegrambots.extensions.bots.commandbot.commands.ICommandRegistry;
import org.telegram.telegrambots.meta.api.methods.send.SendMessage;
import org.telegram.telegrambots.meta.api.objects.Chat;
import org.telegram.telegrambots.meta.api.objects.User;
import org.telegram.telegrambots.meta.bots.AbsSender;
import org.telegram.telegrambots.meta.exceptions.TelegramApiException;

import java.util.Collection;

/**
 * A special bot command used for printing help messages similiar to the Linux man command.
 * The commands printed by this command should implement the {@link IManCommand} interface to provide an extended description.
 * @author Lukas Prediger(Chase)
 * @version 1.0.0
 *
 */
public class HelpCommand extends ManCommand {
	
	private static final String COMMAND_IDENTIFIER = "help";
	private static final String COMMAND_DESCRIPTION = "shows all commands. Use /help [command] for more info";
	private static final String EXTENDED_DESCRIPTION = "This command displays all commands the bot has to offer.\n /help [command] can display deeper information";
	
	/**
	 * Returns the command and description of all supplied commands as a formatted String
	 * @param botCommands the Commands that should be included in the String
	 * @return a formatted String containing command and description for all supplied commands
	 */
	public static String getHelpText(IBotCommand...botCommands) {
		StringBuilder reply = new StringBuilder();
		for (IBotCommand com : botCommands) {
			reply.append(com.toString()).append(System.lineSeparator()).append(System.lineSeparator());
		}
		return reply.toString();
	}

	/**
	 * Returns the command and description of all supplied commands as a formatted String
	 * @param botCommands a collection of commands that should be included in the String
	 * @return a formatted String containing command and description for all supplied commands
	 */
	public static String getHelpText(Collection<IBotCommand> botCommands) {
		return getHelpText(botCommands.toArray(new IBotCommand[0]));
	}

	/**
	 * Returns the command and description of all supplied commands as a formatted String
	 * @param registry a commandRegistry which commands are formatted into the String
	 * @return a formatted String containing command and description for all supplied commands
	 */
	public static String getHelpText(ICommandRegistry registry) {
		return getHelpText(registry.getRegisteredCommands());
	}
	
	/**
	 * Reads the extended Description from a BotCommand. If the Command is not of Type {@link IManCommand}, it calls toString();
	 * @param command a command the extended Descriptions is read from
	 * @return the extended Description or the toString() if IManCommand is not implemented
	 */
	public static String getManText(IBotCommand command) {
		return IManCommand.class.isInstance(command) ? getManText((IManCommand) command) : command.toString();
	}
	
	/**
	 * Reads the extended Description from a BotCommand;
	 * @param command a command the extended Descriptions is read from
	 * @return the extended Description
	 */
	public static String getManText(IManCommand command) {
		return command.toMan();
	}
	
	/**
	 * Create a Help command with the standard Arguments.
	 */
	public HelpCommand() {
		super(COMMAND_IDENTIFIER, COMMAND_DESCRIPTION, EXTENDED_DESCRIPTION);
	}
	
	/**
	 * Creates a Help Command with custom identifier, description and extended Description
	* @param commandIdentifier the unique identifier of this command (e.g. the command string to enter into chat)
     * @param description the description of this command
	 * @param extendedDescription The extended Description for the Command, should provide detailed information about arguments and possible options
	 */
	public HelpCommand(String commandIdentifier, String description, String extendedDescription) {
		super(commandIdentifier, description, extendedDescription);
	}
	
	@Override
	public void execute(AbsSender absSender, User user, Chat chat, String[] arguments) {
		if (ICommandRegistry.class.isInstance(absSender)) {
			ICommandRegistry registry = (ICommandRegistry) absSender;
			
			if (arguments.length > 0) {
				IBotCommand command = registry.getRegisteredCommand(arguments[0]);
				String reply = getManText(command);
				try {
					absSender.execute(SendMessage.builder().chatId(chat.getId()).text(reply).parseMode("HTML").build());
				} catch (TelegramApiException e) {
					e.printStackTrace();
				}
			} else {
				String reply = getHelpText(registry);
				try {
					absSender.execute(SendMessage.builder().chatId(chat.getId()).text(reply).parseMode("HTML").build());
				} catch (TelegramApiException e) {
					e.printStackTrace();
				}
			}
		}
	}

}