scrawl/game/view.go

package game

import (
	"fmt"
	"strings"

	"github.com/charmbracelet/lipgloss"
)

// Generated via `figlet -f slant SCRAWL` — the slant felt right for a
// doodle/scribble tool, not hand-tuned character by character.
const banner = `   _____ __________  ___ _       ____
  / ___// ____/ __ \/   | |     / / /
  \__ \/ /   / /_/ / /| | | /| / / /
 ___/ / /___/ _, _/ ___ | |/ |/ / /___
/____/\____/_/ |_/_/  |_|__/|__/_____/`

func (m Model) View() string {
	if m.state == stateIntro {
		return m.renderIntro()
	}
	return m.renderCanvas()
}

// style is a small accessor so every render call goes through m.renderer
// (bound to this specific SSH session's actual output) rather than
// lipgloss's package-level default styles, which detect color support
// from the *server process's* os.Stdout -- not any given session's
// terminal. That's a real bug this app hit: the server's stdout is
// typically redirected (a log file, a systemd journal, anything that
// isn't a TTY), so the default global renderer silently disabled all
// color/background styling for every connected session at once,
// regardless of what terminal they were actually using.
func (m Model) style() lipgloss.Style {
	return m.renderer.NewStyle()
}

func (m Model) renderIntro() string {
	title := m.style().Bold(true).Foreground(lipgloss.Color("#ff6b6b")).Render(banner)
	dim := m.style().Foreground(lipgloss.Color("#777777"))
	body := title + "\n" +
		dim.Render("a shared doodle wall, one keystroke at a time") + "\n\n" +
		"Everyone connected right now is drawing on the same canvas.\n" +
		"Move with arrow keys or hjkl, space/enter to paint, backspace to\n" +
		"erase. [ and ] cycle the ink character, 1-8 pick a color, c clears\n" +
		"everything for everyone (yes, really — it's a shared wall).\n\n" +
		dim.Render("press any key to start")
	return m.boxStyle().Render(body)
}

func (m Model) boxStyle() lipgloss.Style {
	return m.style().Border(lipgloss.RoundedBorder()).
		BorderForeground(lipgloss.Color("#555555")).Padding(1, 2)
}

func (m Model) renderCanvas() string {
	cells, cursors := m.canvas.Snapshot()

	// Cursors are a background highlight on whatever's actually painted at
	// that cell, not a glyph that replaces it -- a glyph-replace bug meant
	// painting a cell your own cursor already sat on was invisible: the
	// cursor marker before and after painting rendered as the exact same
	// character in the exact same color, so bubbletea's diffing renderer
	// (correctly) sent zero bytes, since nothing had visually changed.
	type painted struct {
		ch    rune
		color string
		bg    string
	}
	grid := make([][]painted, Height)
	for y := 0; y < Height; y++ {
		grid[y] = make([]painted, Width)
		for x := 0; x < Width; x++ {
			c := cells[y][x]
			if c.Char == 0 {
				grid[y][x] = painted{ch: ' '}
			} else {
				grid[y][x] = painted{ch: c.Char, color: c.Color}
			}
		}
	}
	for id, cur := range cursors {
		if id == m.id {
			continue
		}
		grid[cur.Y][cur.X].bg = cur.Color
	}
	if self, ok := cursors[m.id]; ok {
		grid[self.Y][self.X].bg = inkPalette[m.inkColorIdx]
	}

	var b strings.Builder
	for y := 0; y < Height; y++ {
		for x := 0; x < Width; x++ {
			p := grid[y][x]
			style := m.style()
			if p.color != "" {
				style = style.Foreground(lipgloss.Color(p.color))
			}
			if p.bg != "" {
				style = style.Background(lipgloss.Color(p.bg)).Foreground(lipgloss.Color("#000000"))
			}
			ch := p.ch
			if ch == 0 || ch == ' ' {
				ch = ' '
			}
			b.WriteString(style.Render(" "))
			b.WriteString(style.Render(string(ch)))
		}
		b.WriteString("\n")
	}

	inkSwatch := m.style().Foreground(lipgloss.Color(inkPalette[m.inkColorIdx])).Render(string(charPalette[m.charIdx]))
	dim := m.style().Foreground(lipgloss.Color("#777777"))
	status := fmt.Sprintf("ink %s  (1-8 color, [ ] char)   peers: %d   %s",
		inkSwatch, m.canvas.PeerCount(), dim.Render("space paint · c clear · q quit"))

	return m.boxStyle().Render(b.String() + "\n" + status)
}