chessbot/chess.go

package main

import (
	"fmt"
	"image/color"
	"os"
	"strings"
	"time"

	"github.com/notnil/chess"
	"github.com/notnil/chess/image"
	"samhofi.us/x/keybase/v2/types/chat1"
)

func chessCommand(m chat1.MsgSummary) {
	defer log.PanicSafe()
	defer saveConfig()
	convID := string(m.ConvID)
	parts := strings.Split(m.Content.Text.Body, " ")
	if g, ok := config.Games[convID]; ok {
		if len(parts) != 2 {
			return
		}
		if parts[1] == "show" {
			go showBoard(m, &g)
			return
		}

		submitMove(m, &g)
		return
	}
	if len(parts) < 3 {
		return
	}
	coin := r.Intn(100)
	log.LogInfo(fmt.Sprintf("Coin toss resulted in %+v\n", coin))
	var game Game
	if coin%2 == 0 {
		if len(parts) == 4 && parts[3] == "heads" {
			game.White = m.Sender.Username
			game.Black = strings.Replace(parts[2], "@", "", -1)

		} else {
			game.Black = m.Sender.Username
			game.White = strings.Replace(parts[2], "@", "", -1)
		}
	} else {
		if len(parts) == 4 && parts[3] == "heads" {
			game.Black = m.Sender.Username
			game.White = strings.Replace(parts[2], "@", "", -1)
		} else {
			game.White = m.Sender.Username
			game.Black = strings.Replace(parts[2], "@", "", -1)
		}
	}
	log.LogDebug("There are currently %+v games.\n", len(config.Games))
	g := chess.NewGame()
	game.Game = g
	game.ConvID = convID
	game.Move = true
	game.StartTime = time.Now()
	config.Games[convID] = game
	k.SendMessageByConvID(m.ConvID, fmt.Sprintf("I have created a new game for this conversation @%+v is playing as White, @%+v is playing as Black.", game.White, game.Black))
	k.SendMessageByConvID(m.ConvID, fmt.Sprintf("Possible commands are `@chessbot show` to show the board, or `@chessbot forfeit`. Otherwise I will be expecting a move in Algebraic Notation."))

}

func showBoard(m chat1.MsgSummary, g *Game) {
	defer log.PanicSafe()
	// create file
	f, err := os.Create(fmt.Sprintf("/home/chessbot/chessbot/games/%+v.svg", m.ConvID))
	if err != nil {
		log.LogError(fmt.Sprintf("Error in ShowBoard os.Create: %+v\n", err))
	}

	// create board position
	fenStr := g.Game.Position().String()
	pos := &chess.Position{}
	if err := pos.UnmarshalText([]byte(fenStr)); err != nil {
		log.LogError(fmt.Sprintf("Error in ShowBoard pos.UnmasrhalText: %+v\n", err))
	}
	if len(g.Game.Moves()) != 0 {
		// write board SVG to file
		yellow := color.RGBA{255, 255, 0, 1}
		lastMove := g.Game.Moves()[len(g.Game.Moves())-1]

		mark := image.MarkSquares(yellow, lastMove.S1(), lastMove.S2())
		if err := image.SVG(f, pos.Board(), mark); err != nil {
			log.LogError("Error in ShowBoard image.SVG Mark: %+v\n", err)
		}
	} else {
		if err := image.SVG(f, pos.Board()); err != nil {
			log.LogError("Error in ShowBoard image.SVG: %+v\n", err)
		}

	}
	f.Close()
	if svgToPNG(fmt.Sprintf("/home/chessbot/chessbot/games/%+v", m.ConvID)) {
		k.UploadToConversation(m.ConvID, "", fmt.Sprintf("/home/chessbot/chessbot/games/%+v.png", m.ConvID))
	} else {
		k.SendMessageByConvID(m.ConvID, fmt.Sprintf("```%+v```", g.Game.Position().Board().Draw()))
	}
}

func submitMove(m chat1.MsgSummary, g *Game) {
	defer log.PanicSafe()
	parts := strings.Split(m.Content.Text.Body, " ")
	if g.Move {
		if m.Sender.Username != g.White {
			k.SendMessageByConvID(m.ConvID, "Wait your turn.")
			return
		}
	} else {
		if m.Sender.Username != g.Black {
			k.SendMessageByConvID(m.ConvID, "Wait your turn.")
			return
		}
	}
	if parts[1] == "forfeit" || parts[1] == "surrender" {
		if g.Move {
			g.Game.Resign(chess.White)
		} else {
			g.Game.Resign(chess.Black)
		}
	} else {
		err := g.Game.MoveStr(parts[1])
		if err != nil {
			k.SendMessageByConvID(m.ConvID, "There was an error with your move.")
			log.LogDebug("%+v\n", err)
			return
		}
	}
	g.Move = !g.Move

	if g.Game.Outcome() != chess.NoOutcome {
		k.SendMessageByConvID(m.ConvID, fmt.Sprintf("Game completed in %+v. %s by %s.\n", time.Since(g.StartTime), g.Game.Outcome(), g.Game.Method()))
		delete(config.Games, g.ConvID)
	}
	go showBoard(m, g)
}