package main

import (
	"bufio"
	"fmt"
	"io"
	"net"
	"sort"
	"strings"
	"time"
)

type Connection struct {
	*bufio.Reader
	game *Game
	net.Conn
	ConnectionState
	bombs    int
	colonies []*System
	kills    int
	lastBomb time.Time
	lastScan time.Time
	money    int
	profile  *Profile
}

func NewConnection(conn net.Conn) *Connection {
	c := &Connection{
		Conn:   conn,
		Reader: bufio.NewReader(conn),
		bombs:  options.startBombs,
		money:  options.startMoney,
	}
	c.SetState(new(LobbyState))
	return c
}

func (c *Connection) Login() {
	for {
		c.Printf("what is your name, adventurer?\n")
		name, err := c.ReadString('\n')
		if err == nil {
			name = strings.TrimSpace(name)
		} else {
			log_error("player failed to connect: %v", err)
			return
		}

		if !ValidName(name) {
			c.Printf("that name is illegal.\n")
			continue
		}
		log_info("player connected: %v", name)
		profile, err := loadProfile(name)
		if err != nil {
			log_error("could not read profile: %v", err)
			profile = &Profile{name: name}
			if err := profile.Create(); err != nil {
				log_error("unable to create profile record: %v", err)
			}
			c.Printf("you look new around these parts, %s.\n", profile.name)
			c.Printf(`if you'd like a description of how to play, type the "help" command\n`)
			c.profile = profile
		} else {
			c.profile = profile
			c.Printf("welcome back, %s.\n", profile.name)
		}
		break
	}
}

func (c *Connection) Dead() bool {
	return false
}

func (c *Connection) Tick(frame int64) {
	if c.ConnectionState == nil {
		log_error("connected client has nil state.")
		c.Printf("somehow you have a nil state.  I don't know what to do so I'm going to kick you off.")
		c.Close()
		return
	}
	c.SetState(c.ConnectionState.Tick(c, frame))
}

func (c *Connection) RunCommand(name string, args ...string) {
	defer func() {
		if r := recover(); r != nil {
			c.Printf("something is broken.  Log this as a ticket!\n")
			c.Printf("recovered: %v\n", r)
			log_error("recovered: %v", r)
		}
	}()
	switch name {
	case "commands":
		c.Line()
		commands := c.Commands()
		names := make([]string, len(commands))
		for i := range commands {
			names[i] = commands[i].name
		}
		sort.Strings(names)
		for _, name := range names {
			cmd := c.GetCommand(name)
			c.Printf("%-20s%s\n", name, cmd.help)
		}
		c.Line()
		return
	}

	cmd := c.GetCommand(name)
	if cmd == nil {
		c.Printf("No such command: %v\n", name)
		return
	}
	cmd.handler(c, args...)
}

func (c *Connection) SetState(s ConnectionState) {
	if c.ConnectionState == s {
		return
	}
	log_info("set state: %v", s)
	if c.ConnectionState != nil {
		log_info("exit state: %v", c.ConnectionState)
		c.ConnectionState.Exit(c)
	}
	log_info("enter state: %v", s)
	s.Enter(c)
	c.ConnectionState = s
}

func (c *Connection) ReadLines(out chan []string) {
	defer close(out)

	for {
		line, err := c.ReadString('\n')
		switch err {
		case io.EOF:
			return
		case nil:
			break
		default:
			log_error("unable to read line on connection: %v", err)
			return
		}
		line = strings.TrimSpace(line)
		if line == "" {
			continue
		}
		out <- strings.Split(line, " ")
	}
}

func (c *Connection) Line() {
	c.Printf("--------------------------------------------------------------------------------\n")
}

func (c *Connection) Printf(template string, args ...interface{}) (int, error) {
	return fmt.Fprintf(c, template, args...)
}

func (c *Connection) Close() error {
	log_info("player disconnecting: %s", c.Name())
	c.game.Quit(c)
	if c.Conn != nil {
		return c.Conn.Close()
	}
	return nil
}

func (c *Connection) Name() string {
	if c.profile == nil {
		return ""
	}
	return c.profile.name
}

func (c *Connection) RecordScan() {
	c.Printf("scanning known systems for signs of life\n")
	c.lastScan = time.Now()
	time.AfterFunc(options.scanTime, func() {
		c.Printf("scanner ready\n")
	})
}

func (c *Connection) RecordBomb() {
	c.lastBomb = time.Now()
	time.AfterFunc(15*time.Second, func() {
		fmt.Fprintln(c, "bomb arsenal reloaded")
	})
}

func (c *Connection) CanScan() bool {
	return time.Since(c.lastScan) > options.scanTime
}

func (c *Connection) NextScan() time.Duration {
	return -time.Since(c.lastScan.Add(options.scanTime))
}

func (c *Connection) NextBomb() time.Duration {
	return -time.Since(c.lastBomb.Add(15 * time.Second))
}

func (c *Connection) MadeKill(victim *Connection) {
	if c == victim {
		log_info("player %s commited suicide.", c.Name())
		return
	}
	c.kills += 1
	if c.kills == 3 {
		c.Win("military")
	}
}

func (c *Connection) Withdraw(n int) {
	c.money -= n
}

func (c *Connection) Deposit(n int) {
	c.money += n
	if c.money >= options.economic {
		c.Win("economic")
	}
}

func (c *Connection) Win(method string) {
	c.game.Win(c, method)
}

func (c *Connection) Die(frame int64) {
	c.SetState(NewDeadState(frame))
}

type ConnectionState interface {
	CommandSuite
	String() string
	Enter(c *Connection)
	Tick(c *Connection, frame int64) ConnectionState
	Exit(c *Connection)
}

// No-op enter struct, for composing connection states that have no interesitng
// Enter mechanic.
type NopEnter struct{}

func (n NopEnter) Enter(c *Connection) {}

// No-op exit struct, for composing connection states that have no interesting
// Exit mechanic.
type NopExit struct{}

func (n NopExit) Exit(c *Connection) {}

func SpawnRandomly() ConnectionState {
	sys, err := randomSystem()
	if err != nil {
		return NewErrorState(fmt.Errorf("unable to create idle state: %v", err))
	}
	return Idle(sys)
}

type LobbyState struct {
	NopExit
}

func (st *LobbyState) String() string { return "Lobby" }

func (st *LobbyState) Enter(c *Connection) {
	c.Login()
}

func (st *LobbyState) Tick(c *Connection, frame int64) ConnectionState { return st }

func (st *LobbyState) Commands() []Command {
	return []Command{newGameCommand, joinGameCommand}
}

func (st *LobbyState) GetCommand(name string) *Command {
	switch name {
	case "new":
		return &newGameCommand
	case "join":
		return &joinGameCommand
	default:
		return nil
	}
}

var newGameCommand = Command{
	name:     "new",
	help:     "starts a new game",
	arity:    0,
	variadic: false,
	handler: func(c *Connection, args ...string) {
		c.Printf("Starting a new game...\n")
		game := gm.NewGame()
		log_info("Created game: %s", game.id)
		go game.Run()
		c.game = game
		c.Printf("Now playing in game: %s\n\n", game.id)
		c.Line()
		c.game.Join(c)
		c.SetState(SpawnRandomly())
	},
	debug: false,
}

var joinGameCommand = Command{
	name:     "join",
	help:     "joins an existing game",
	arity:    1,
	variadic: false,
	handler: func(c *Connection, args ...string) {
		id := args[0]
		c.game = gm.Get(id)
		c.SetState(SpawnRandomly())
		c.game.Join(c)
	},
	debug: false,
}