package main

import (
	"math/rand"
	"strconv"
	"strings"
	"sync"
)

type CommandHandlerFunc func(args []string, clientID int) string

type CommandRegistry struct {
	commands map[string]CommandHandlerFunc
	mutex    sync.Mutex // Mutex to safely access commands map
}

func NewCommandRegistry() *CommandRegistry {
	return &CommandRegistry{
		commands: make(map[string]CommandHandlerFunc),
	}
}

func (cr *CommandRegistry) RegisterCommand(command string, handler CommandHandlerFunc) {
	cr.mutex.Lock()
	defer cr.mutex.Unlock()
	cr.commands[command] = handler
}

func (cr *CommandRegistry) GetCommandHandler(command string, clientID int) (CommandHandlerFunc, bool, int) {
	cr.mutex.Lock()
	defer cr.mutex.Unlock()
	handler, ok := cr.commands[command]
	return handler, ok, clientID
}

func RegisterCommands(registry *CommandRegistry) {
	registry.RegisterCommand("help", HelpCommand)
	registry.RegisterCommand("setname", SetNameCommand)
	registry.RegisterCommand("list", ListClientsCommand)
	registry.RegisterCommand("tell", TellClientCommand)
	registry.RegisterCommand("clear", ClearCommand)
	registry.RegisterCommand("rng", RandomCommand)
	registry.RegisterCommand("challenge", StartCommand)
	registry.RegisterCommand("accept", AcceptCommand)
	registry.RegisterCommand("shoot", ShootCommand)
	// Add more commands here...
}

func ShootCommand(args []string, clientID int) string {
	if clients[clientID].match.round >= 0 {
		self := false
		if len(args) == 1 {
			if strings.ToLower(args[0]) == "self" {
				self = true
			} else if getByIDOrName(args[0]) == clientID {
				self = true
			}
		}
		var fired bool
		if self {
			fired = clients[clientID].match.gun.Shoot(clients[clientID])
			if fired {
				return "Shot self with a live"
			} else {
				return "Shot self with a blank"
			}
		} else {
			if clients[clientID].isHost {
				fired = clients[clientID].match.gun.Shoot(clients[clientID].match.guest)
			} else {
				fired = clients[clientID].match.gun.Shoot(clients[clientID].match.host)
			}
			if fired {
				return "Shot " + args[0] + "with a live"
			} else {
				return "Shot " + args[0] + "with a blank"
			}
		}
	}
	return "Error"
}

func AcceptCommand(args []string, clientID int) string {
	clientsMutex.Lock()
	defer clientsMutex.Unlock()
	matchesMutex.Lock()
	defer matchesMutex.Unlock()
	if clients[clientID].match.guest == clients[clientID] {
		clients[clientID].match.round = 0
		clients[clientID].match.host.sendMessage("Accepted", clients[clientID])
		clients[clientID].isHost = false
		clients[clientID].match.gun.Reload(8)
		return "Accepted"
	}
	return "No match to accept"
}

func StartCommand(args []string, clientID int) string {
	if len(args) == 1 {
		targetID := getByIDOrName(args[0])
		if targetID >= 0 {
			match := Match{
				host:  clients[clientID],
				guest: clients[targetID],
				round: -1,
				gun: Gun{
					doubled: false,
				},
			}
			clientsMutex.Lock()
			clients[clientID].match = &match
			clients[targetID].match = &match
			clients[targetID].sendMessage("Type \"accept\" to accept a match.", clients[clientID])
			clientsMutex.Unlock()
			matchesMutex.Lock()
			matches = append(matches, &match)
			matchesMutex.Unlock()
		} else {
			return "Unknown user"
		}
	}
	return "Invalid argument"
}

func HelpCommand(args []string, clientID int) string {
	// Handle help command
	if len(clients) > 0 {
		return "Just help yourself, " + clients[clientID].Username
	}
	return "No clients available"
}

func RandomCommand(args []string, clientID int) string {
	// Handle help command
	if len(args) == 2 {
		from, err1 := strconv.Atoi(args[0])
		to, err2 := strconv.Atoi(args[1])
		if err1 != nil || err2 != nil {
			return "Invalid argument"
		}
		if to-from <= 0 {
			return "Invalid range"
		}
		return "The number is " + strconv.Itoa(rand.Intn(to-from)+from)
	}
	return "No range provided"
}

func ClearCommand(args []string, clientID int) string {
	// Handle help command
	return "\033[H\033[2J\033[K"
}

func SetNameCommand(args []string, clientID int) string {
	// Handle help command
	if len(args) == 1 {
		newName := args[0]
		clients[clientID].Username = newName
		return "Name set to " + newName
	}
	return "No name provided"
}

func ListClientsCommand(args []string, clientID int) string {
	message := ""
	for i, client := range clients {
		message += strconv.Itoa(i) + ": " + client.Username + "\n"
	}
	return message
}

func TellClientCommand(args []string, clientID int) string {
	message := "Message not delivered"
	if len(args) >= 2 {
		toClientID := getByIDOrName(args[0])
		if toClientID >= 0 {
			toClientName := clients[toClientID].Username
			newMessage := ""
			//all the remaining arguments are a part of the message, join them with space
			for i, arg := range args {
				if i > 0 {
					newMessage += arg + " "
				}
			}
			clients[toClientID].sendMessage(newMessage, clients[clientID])
			return "Message sent to " + toClientName
		} else {
			message = "Invalid recipient"
		}
	}
	return message
}