scrawl/game/model.go

package game

import (
	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"
)

var inkPalette = []string{"#ff6b6b", "#feca57", "#1dd1a1", "#54a0ff", "#ff9ff3", "#48dbfb", "#f368e0", "#ffffff"}
var charPalette = []rune{'█', '▓', '▒', '░', '#', '*', '.', '@', 'o', '+'}

type state int

const (
	stateIntro state = iota
	stateCanvas
)

type Model struct {
	canvas   *Canvas
	id       string
	label    string
	state    state
	renderer *lipgloss.Renderer

	inkColorIdx int
	charIdx     int

	width, height int
}

func NewModel(canvas *Canvas, id, label string, renderer *lipgloss.Renderer) Model {
	return Model{canvas: canvas, id: id, label: label, state: stateIntro, renderer: renderer}
}

func (m Model) Init() tea.Cmd { return nil }

func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	switch msg := msg.(type) {
	case tea.WindowSizeMsg:
		m.width, m.height = msg.Width, msg.Height
		return m, nil

	case canvasUpdatedMsg:
		// Someone (possibly this session) changed the shared state --
		// nothing to do here but re-render; View() always reads a fresh
		// snapshot from the canvas.
		return m, nil

	case tea.KeyMsg:
		if m.state == stateIntro {
			m.state = stateCanvas
			return m, nil
		}
		return m.handleKey(msg)
	}
	return m, nil
}

func (m Model) handleKey(msg tea.KeyMsg) (tea.Model, tea.Cmd) {
	switch msg.String() {
	case "ctrl+c", "q":
		return m, tea.Quit

	case "up", "k":
		m.canvas.MoveCursor(m.id, 0, -1)
	case "down", "j":
		m.canvas.MoveCursor(m.id, 0, 1)
	case "left", "h":
		m.canvas.MoveCursor(m.id, -1, 0)
	case "right", "l":
		m.canvas.MoveCursor(m.id, 1, 0)

	case " ", "enter":
		if cur, ok := m.canvas.CursorsSnapshot()[m.id]; ok {
			m.canvas.Paint(cur.X, cur.Y, charPalette[m.charIdx], inkPalette[m.inkColorIdx])
		}

	case "backspace", "delete":
		if cur, ok := m.canvas.CursorsSnapshot()[m.id]; ok {
			m.canvas.Paint(cur.X, cur.Y, ' ', "")
		}

	case ",", "[":
		m.charIdx = (m.charIdx - 1 + len(charPalette)) % len(charPalette)
	case ".", "]":
		m.charIdx = (m.charIdx + 1) % len(charPalette)

	case "1", "2", "3", "4", "5", "6", "7", "8":
		m.inkColorIdx = int(msg.String()[0] - '1')

	case "c":
		m.canvas.Clear()
	}
	return m, nil
}