feat: move pieces

board.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"fmt"
+	"strings"
 
 	"github.com/charmbracelet/lipgloss"
 )
@@ -26,18 +27,36 @@ var faintStyle = lipgloss.NewStyle().Faint(true)
 
 type Board struct {
 	Players []Player
-	Grid    [dimensions][dimensions]string
+	Grid    [dimensions][dimensions]*Piece
 	flipped bool
 }
 
+func (b *Board) Move(from, to position) {
+	p := b.Grid[from[0]-1][from[1]-1]
+	if p == nil {
+		return
+	}
+	b.Grid[from[0]-1][from[1]-1] = nil
+	b.Grid[to[0]-1][to[1]-1] = p
+	p.Position = to
+}
+
 func (b *Board) Draw() {
 	for _, player := range b.Players {
 		for _, piece := range player.Pieces {
-			b.Grid[piece.Position[0]-1][piece.Position[1]-1] = piece.String()
+			p := piece
+			b.Grid[piece.Position[0]-1][piece.Position[1]-1] = p
 		}
 	}
 }
 
+func FileToColumn(file string) int {
+	if len(file) < 1 {
+		return 0
+	}
+	return int([]rune(strings.ToUpper(file))[0] - 64)
+}
+
 func (b *Board) String() string {
 	var s = header
 
@@ -50,17 +69,17 @@ func (b *Board) String() string {
 	}
 
 	for row, rank := range ranks {
-		for col := firstCol; col < dimensions; col++ {
-			if col == firstCol {
+		for file := firstCol; file < dimensions; file++ {
+			if file == firstCol {
 				s += faintStyle.Render(fmt.Sprintf(" %d ", rank+1))
 			}
 			s += divider
-			if b.Grid[rank][col] == "" {
+			if b.Grid[rank][file] == nil {
 				s += " "
 			} else {
-				s += b.Grid[rank][col]
+				s += b.Grid[rank][file].String()
 			}
-			if col == lastCol {
+			if file == lastCol {
 				s += divider
 			}
 		}

main.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"log"
+	"strconv"
 
 	tea "github.com/charmbracelet/bubbletea"
 )
@@ -20,6 +21,10 @@ func main() {
 
 type model struct {
 	Board Board
+	Move  struct {
+		From position
+		To   position
+	}
 }
 
 func (m model) Init() tea.Cmd { return nil }
@@ -32,6 +37,25 @@ func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		switch msg.String() {
 		case "ctrl+c", "q", "esc":
 			return m, tea.Quit
+		case "1", "2", "3", "4", "5", "6", "7", "8":
+			if m.Move.To[1] > 0 {
+				i, _ := strconv.Atoi(msg.String())
+				m.Move.To[0] = i
+				m.Board.Move(m.Move.From, m.Move.To)
+				m.Move.From, m.Move.To = position{}, position{}
+				return m, nil
+			}
+			i, _ := strconv.Atoi(msg.String())
+			m.Move.From[0] = i
+		case "a", "b", "c", "d", "e", "f", "g", "h",
+			"A", "B", "C", "D", "E", "F", "G", "H":
+			if m.Move.From[0] > 0 {
+				m.Move.To[1] = FileToColumn(msg.String())
+				return m, nil
+			}
+
+			m.Move.From[1] = FileToColumn(msg.String())
+			return m, nil
 		case "ctrl+f":
 			m.Board.flipped = !m.Board.flipped
 			return m, nil
@@ -42,5 +66,5 @@ func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 }
 
 func (m model) View() string {
-	return m.Board.String()
+	return m.Board.String() + "\n\n" + m.Move.From.String() + " " + m.Move.To.String()
 }

piece.go

@@ -39,20 +39,21 @@ var pieces = map[color]map[piece]string{
 	},
 }
 
-// array of [row, column]
-// e.g. [1, 4]
+// array of [row,  column]
+// array of [rank, file]
+// e.g. [1, 4] (D1)
 type position [2]int
 
 func (p position) String() string {
-	return p.Row() + p.Col()
+	return p.File() + p.Rank()
 }
 
-func (p position) Row() string {
-	return string(rune('A' - 1 + p[0]))
+func (p position) File() string {
+	return string(rune('A' - 1 + p[1]))
 }
 
-func (p position) Col() string {
-	return fmt.Sprint(p[1])
+func (p position) Rank() string {
+	return fmt.Sprint(p[0])
 }
 
 type Piece struct {
@@ -66,16 +67,16 @@ func (p Piece) String() string {
 	return pieces[p.Color][p.Type]
 }
 
-func NewPiece(piece piece, position position, color color) Piece {
-	return Piece{
+func NewPiece(piece piece, position position, color color) *Piece {
+	return &Piece{
 		Type:     piece,
 		Position: position,
 		Color:    color,
 	}
 }
 
-func InitialPieces(color color) []Piece {
-	var pieces []Piece
+func InitialPieces(color color) []*Piece {
+	var pieces []*Piece
 	var (
 		pawnRank int
 		backRank int
@@ -98,10 +99,10 @@ func InitialPieces(color color) []Piece {
 	return pieces
 }
 
-func BlackPieces() []Piece {
+func BlackPieces() []*Piece {
 	return InitialPieces(Black)
 }
 
-func WhitePieces() []Piece {
+func WhitePieces() []*Piece {
 	return InitialPieces(White)
 }

player.go

@@ -2,6 +2,6 @@ package main
 
 type Player struct {
 	Points   int
-	Pieces   []Piece
-	Captured []Piece
+	Pieces   []*Piece
+	Captured []*Piece
 }