commit c64cf631253bef2f19b8b9f50ebaab99633c9e8a
Author: Levi Neely <lneely@pascom.net>
Date:   Wed Jun 24 13:43:01 2026 +0200

    initial commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..6c7e231
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/wmon
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..bc02043
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,5 @@
+module wmon
+
+go 1.26.2
+
+require github.com/gotk3/gotk3 v0.6.3
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..7b006a9
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,4 @@
+github.com/gotk3/gotk3 v0.6.3 h1:+Ke4WkM1TQUNOlM2TZH6szqknqo+zNbX3BZWVXjSHYw=
+github.com/gotk3/gotk3 v0.6.3/go.mod h1:/hqFpkNa9T3JgNAE2fLvCdov7c5bw//FHNZrZ3Uv9/Q=
+github.com/gotk3/gotk3 v0.6.4 h1:5ur/PRr86PwCG8eSj98D1eXvhrNNK6GILS2zq779dCg=
+github.com/gotk3/gotk3 v0.6.4/go.mod h1:/hqFpkNa9T3JgNAE2fLvCdov7c5bw//FHNZrZ3Uv9/Q=
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..0408a4a
--- /dev/null
+++ b/main.go
@@ -0,0 +1,564 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"math"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
+
+	"github.com/gotk3/gotk3/cairo"
+	"github.com/gotk3/gotk3/gdk"
+	"github.com/gotk3/gotk3/gtk"
+)
+
+type Monitor struct {
+	Name    string
+	Model   string
+	Width   int
+	Height  int
+	X       int
+	Y       int
+	Enabled bool
+	Refresh float64
+	Scale   float64
+}
+
+type App struct {
+	window    *gtk.Window
+	canvas    *gtk.DrawingArea
+	monitors  []Monitor
+	dragging  int // index of monitor being dragged, -1 if none
+	dragOffX  float64
+	dragOffY  float64
+	scale     float64 // view scale (pixels per monitor-pixel)
+	offsetX   float64 // view pan offset
+	offsetY   float64
+	panning   bool
+	panStartX float64
+	panStartY float64
+	panOffX   float64
+	panOffY   float64
+	layoutSet bool
+}
+
+func parseWlrRandr() ([]Monitor, error) {
+	out, err := exec.Command("wlr-randr").Output()
+	if err != nil {
+		return nil, err
+	}
+
+	var monitors []Monitor
+	var cur *Monitor
+	lines := strings.Split(string(out), "\n")
+
+	nameRe := regexp.MustCompile(`^(\S+)\s+"(.+)"`)
+	modeRe := regexp.MustCompile(`^\s+(\d+)x(\d+)\s+px,\s+([\d.]+)\s+Hz\s*(.*)`)
+	posRe := regexp.MustCompile(`^\s+Position:\s+(\d+),(\d+)`)
+	enabledRe := regexp.MustCompile(`^\s+Enabled:\s+(\w+)`)
+	scaleRe := regexp.MustCompile(`^\s+Scale:\s+([\d.]+)`)
+
+	for _, line := range lines {
+		if m := nameRe.FindStringSubmatch(line); m != nil {
+			if cur != nil {
+				monitors = append(monitors, *cur)
+			}
+			cur = &Monitor{Name: m[1], Model: m[2], Scale: 1.0}
+		} else if cur != nil {
+			if m := enabledRe.FindStringSubmatch(line); m != nil {
+				cur.Enabled = m[1] == "yes"
+			} else if m := modeRe.FindStringSubmatch(line); m != nil {
+				if strings.Contains(m[4], "current") {
+					cur.Width, _ = strconv.Atoi(m[1])
+					cur.Height, _ = strconv.Atoi(m[2])
+					cur.Refresh, _ = strconv.ParseFloat(m[3], 64)
+				}
+			} else if m := posRe.FindStringSubmatch(line); m != nil {
+				cur.X, _ = strconv.Atoi(m[1])
+				cur.Y, _ = strconv.Atoi(m[2])
+			} else if m := scaleRe.FindStringSubmatch(line); m != nil {
+				cur.Scale, _ = strconv.ParseFloat(m[1], 64)
+			}
+		}
+	}
+	if cur != nil {
+		monitors = append(monitors, *cur)
+	}
+	return monitors, nil
+}
+
+func (app *App) fitToCanvas() {
+	alloc := app.canvas.GetAllocation()
+	canvasW := float64(alloc.GetWidth())
+	canvasH := float64(alloc.GetHeight())
+	if canvasW < 10 || canvasH < 10 {
+		canvasW, canvasH = 900, 600
+	}
+
+	// Find bounding box of all monitors (enabled ones for position, disabled get parked)
+	minX, minY := math.MaxFloat64, math.MaxFloat64
+	maxX, maxY := -math.MaxFloat64, -math.MaxFloat64
+	hasEnabled := false
+	for _, m := range app.monitors {
+		if !m.Enabled {
+			continue
+		}
+		hasEnabled = true
+		if float64(m.X) < minX {
+			minX = float64(m.X)
+		}
+		if float64(m.Y) < minY {
+			minY = float64(m.Y)
+		}
+		if float64(m.X+m.Width) > maxX {
+			maxX = float64(m.X + m.Width)
+		}
+		if float64(m.Y+m.Height) > maxY {
+			maxY = float64(m.Y + m.Height)
+		}
+	}
+	if !hasEnabled {
+		app.scale = 0.15
+		app.offsetX = canvasW / 2
+		app.offsetY = canvasH / 3
+		return
+	}
+
+	totalW := maxX - minX
+	totalH := maxY - minY
+	padding := 80.0
+
+	scaleX := (canvasW - padding) / totalW
+	scaleY := (canvasH*0.7 - padding) / totalH
+	app.scale = math.Min(scaleX, scaleY)
+
+	// Center
+	cx := (minX + maxX) / 2
+	cy := (minY + maxY) / 2
+	app.offsetX = canvasW/2 - cx*app.scale
+	app.offsetY = canvasH*0.35 - cy*app.scale
+}
+
+// Convert monitor coords to canvas coords
+func (app *App) monToCanvas(mx, my float64) (float64, float64) {
+	return mx*app.scale + app.offsetX, my*app.scale + app.offsetY
+}
+
+// Convert canvas coords to monitor coords
+func (app *App) canvasToMon(cx, cy float64) (float64, float64) {
+	return (cx - app.offsetX) / app.scale, (cy - app.offsetY) / app.scale
+}
+
+func (app *App) monRect(m Monitor) (float64, float64, float64, float64) {
+	x, y := app.monToCanvas(float64(m.X), float64(m.Y))
+	w := float64(m.Width) * app.scale
+	h := float64(m.Height) * app.scale
+	return x, y, w, h
+}
+
+func (app *App) inactiveY() float64 {
+	alloc := app.canvas.GetAllocation()
+	return float64(alloc.GetHeight()) * 0.78
+}
+
+func (app *App) inactiveRect(idx int) (float64, float64, float64, float64) {
+	inactiveIdx := 0
+	for i := 0; i < idx; i++ {
+		if !app.monitors[i].Enabled {
+			inactiveIdx++
+		}
+	}
+	w := 150.0
+	h := 100.0
+	x := 20.0 + float64(inactiveIdx)*(w+20)
+	y := app.inactiveY() + 30
+	return x, y, w, h
+}
+
+func (app *App) hitTest(cx, cy float64) int {
+	for i := len(app.monitors) - 1; i >= 0; i-- {
+		m := app.monitors[i]
+		var x, y, w, h float64
+		if !m.Enabled {
+			x, y, w, h = app.inactiveRect(i)
+		} else {
+			x, y, w, h = app.monRect(m)
+		}
+		if cx >= x && cx <= x+w && cy >= y && cy <= y+h {
+			return i
+		}
+	}
+	return -1
+}
+
+func (app *App) draw(da *gtk.DrawingArea, cr *cairo.Context) {
+	alloc := da.GetAllocation()
+	canvasW := float64(alloc.GetWidth())
+	canvasH := float64(alloc.GetHeight())
+
+	if !app.layoutSet {
+		app.fitToCanvas()
+		app.layoutSet = true
+	}
+
+	// Background
+	cr.SetSourceRGB(0.15, 0.15, 0.18)
+	cr.Rectangle(0, 0, canvasW, canvasH)
+	cr.Fill()
+
+	// Inactive area
+	iy := app.inactiveY()
+	cr.SetSourceRGB(0.1, 0.1, 0.12)
+	cr.Rectangle(0, iy, canvasW, canvasH-iy)
+	cr.Fill()
+
+	cr.SetSourceRGB(0.4, 0.4, 0.4)
+	cr.SetLineWidth(1)
+	cr.MoveTo(0, iy)
+	cr.LineTo(canvasW, iy)
+	cr.Stroke()
+
+	cr.SetSourceRGB(0.5, 0.5, 0.5)
+	cr.SetFontSize(12)
+	cr.MoveTo(10, iy+18)
+	cr.ShowText("Inactive / Off — drag monitors here to disable")
+
+	// Draw enabled monitors
+	for i, m := range app.monitors {
+		if !m.Enabled {
+			continue
+		}
+		x, y, w, h := app.monRect(m)
+		app.drawMonitor(cr, x, y, w, h, m, i == app.dragging)
+	}
+
+	// Draw inactive monitors
+	for i, m := range app.monitors {
+		if m.Enabled {
+			continue
+		}
+		x, y, w, h := app.inactiveRect(i)
+		app.drawMonitor(cr, x, y, w, h, m, i == app.dragging)
+	}
+}
+
+func (app *App) drawMonitor(cr *cairo.Context, x, y, w, h float64, m Monitor, selected bool) {
+	bezel := 4.0
+
+	if selected {
+		cr.SetSourceRGB(0.3, 0.6, 1.0)
+	} else if m.Enabled {
+		cr.SetSourceRGB(0.3, 0.3, 0.35)
+	} else {
+		cr.SetSourceRGB(0.25, 0.25, 0.28)
+	}
+	cr.Rectangle(x-bezel, y-bezel, w+bezel*2, h+bezel*2+15)
+	cr.Fill()
+
+	if m.Enabled {
+		cr.SetSourceRGB(0.2, 0.25, 0.35)
+	} else {
+		cr.SetSourceRGB(0.12, 0.12, 0.15)
+	}
+	cr.Rectangle(x, y, w, h)
+	cr.Fill()
+
+	// Stand
+	standW := w * 0.3
+	cr.SetSourceRGB(0.25, 0.25, 0.28)
+	cr.Rectangle(x+w/2-standW/2, y+h+bezel, standW, 12)
+	cr.Fill()
+
+	// Labels
+	cr.SetSourceRGB(0.9, 0.9, 0.9)
+	fontSize := math.Max(10, math.Min(14, w/10))
+	cr.SetFontSize(fontSize)
+	cr.MoveTo(x+5, y+fontSize+3)
+	cr.ShowText(m.Name)
+
+	cr.SetSourceRGB(0.6, 0.6, 0.6)
+	cr.SetFontSize(fontSize * 0.8)
+	cr.MoveTo(x+5, y+fontSize*2+3)
+	cr.ShowText(fmt.Sprintf("%dx%d", m.Width, m.Height))
+
+	if m.Enabled {
+		cr.SetSourceRGB(0.5, 0.5, 0.5)
+		cr.SetFontSize(fontSize * 0.7)
+		cr.MoveTo(x+5, y+fontSize*2.8+3)
+		cr.ShowText(fmt.Sprintf("pos: %d,%d", m.X, m.Y))
+	}
+}
+
+func (app *App) onPress(ev *gdk.Event) {
+	btn := gdk.EventButtonNewFromEvent(ev)
+	x, y := btn.X(), btn.Y()
+
+	switch btn.Button() {
+	case 1: // Left click - drag monitor
+		app.dragging = app.hitTest(x, y)
+		if app.dragging >= 0 {
+			m := app.monitors[app.dragging]
+			if m.Enabled {
+				mx, my, _, _ := app.monRect(m)
+				app.dragOffX = x - mx
+				app.dragOffY = y - my
+			} else {
+				ix, iy, _, _ := app.inactiveRect(app.dragging)
+				app.dragOffX = x - ix
+				app.dragOffY = y - iy
+			}
+		}
+	case 2: // Middle click - pan
+		app.panning = true
+		app.panStartX = x
+		app.panStartY = y
+		app.panOffX = app.offsetX
+		app.panOffY = app.offsetY
+	}
+}
+
+func (app *App) onRelease(ev *gdk.Event) {
+	btn := gdk.EventButtonNewFromEvent(ev)
+	switch btn.Button() {
+	case 1:
+		app.dragging = -1
+	case 2:
+		app.panning = false
+	}
+}
+
+func (app *App) onMotion(ev *gdk.Event) {
+	motion := gdk.EventMotionNewFromEvent(ev)
+	x, y := motion.MotionVal()
+
+	if app.panning {
+		app.offsetX = app.panOffX + (x - app.panStartX)
+		app.offsetY = app.panOffY + (y - app.panStartY)
+		app.canvas.QueueDraw()
+		return
+	}
+
+	if app.dragging < 0 {
+		return
+	}
+
+	// Check if dragging into/out of inactive area
+	if y > app.inactiveY() {
+		app.monitors[app.dragging].Enabled = false
+		app.canvas.QueueDraw()
+		return
+	}
+
+	// Enable if was inactive
+	app.monitors[app.dragging].Enabled = true
+
+	// Convert canvas position to monitor coords
+	newCX := x - app.dragOffX
+	newCY := y - app.dragOffY
+	mx, my := app.canvasToMon(newCX, newCY)
+
+	// Snap to 10px grid
+	snapX := int(math.Round(mx/10)) * 10
+	snapY := int(math.Round(my/10)) * 10
+
+	app.monitors[app.dragging].X = snapX
+	app.monitors[app.dragging].Y = snapY
+	app.canvas.QueueDraw()
+}
+
+func (app *App) onScroll(ev *gdk.Event) {
+	scroll := gdk.EventScrollNewFromEvent(ev)
+	dy := scroll.DeltaY()
+
+	// Also handle discrete scroll (non-smooth)
+	if dy == 0 {
+		switch scroll.Direction() {
+		case gdk.SCROLL_UP:
+			dy = -1
+		case gdk.SCROLL_DOWN:
+			dy = 1
+		default:
+			return
+		}
+	}
+
+	// Zoom toward cursor
+	x, y := scroll.X(), scroll.Y()
+	oldScale := app.scale
+
+	if dy < 0 {
+		app.scale *= 1.15
+	} else {
+		app.scale /= 1.15
+	}
+	// Clamp
+	app.scale = math.Max(0.02, math.Min(1.0, app.scale))
+
+	// Adjust offset so point under cursor stays fixed
+	app.offsetX = x - (x-app.offsetX)*(app.scale/oldScale)
+	app.offsetY = y - (y-app.offsetY)*(app.scale/oldScale)
+
+	app.canvas.QueueDraw()
+}
+
+func configDir() string {
+	dir, _ := os.UserConfigDir()
+	p := filepath.Join(dir, "wmon")
+	os.MkdirAll(p, 0755)
+	return p
+}
+
+func (app *App) saveConfig() {
+	dialog, _ := gtk.FileChooserDialogNewWith2Buttons("Save Layout", app.window,
+		gtk.FILE_CHOOSER_ACTION_SAVE, "Cancel", gtk.RESPONSE_CANCEL, "Save", gtk.RESPONSE_ACCEPT)
+	dialog.SetCurrentFolder(configDir())
+	dialog.SetCurrentName("layout.json")
+	dialog.SetDoOverwriteConfirmation(true)
+
+	filter, _ := gtk.FileFilterNew()
+	filter.AddPattern("*.json")
+	filter.SetName("JSON files")
+	dialog.AddFilter(filter)
+
+	if dialog.Run() == gtk.RESPONSE_ACCEPT {
+		path := dialog.GetFilename()
+		data, _ := json.MarshalIndent(app.monitors, "", "  ")
+		if err := os.WriteFile(path, data, 0644); err != nil {
+			log.Printf("Save error: %v", err)
+		}
+	}
+	dialog.Destroy()
+}
+
+func (app *App) loadConfig() {
+	dialog, _ := gtk.FileChooserDialogNewWith2Buttons("Load Layout", app.window,
+		gtk.FILE_CHOOSER_ACTION_OPEN, "Cancel", gtk.RESPONSE_CANCEL, "Open", gtk.RESPONSE_ACCEPT)
+	dialog.SetCurrentFolder(configDir())
+
+	filter, _ := gtk.FileFilterNew()
+	filter.AddPattern("*.json")
+	filter.SetName("JSON files")
+	dialog.AddFilter(filter)
+
+	if dialog.Run() == gtk.RESPONSE_ACCEPT {
+		path := dialog.GetFilename()
+		data, err := os.ReadFile(path)
+		if err != nil {
+			log.Printf("Load error: %v", err)
+			dialog.Destroy()
+			return
+		}
+		var monitors []Monitor
+		if err := json.Unmarshal(data, &monitors); err != nil {
+			log.Printf("Parse error: %v", err)
+			dialog.Destroy()
+			return
+		}
+		app.monitors = monitors
+		app.layoutSet = false
+		app.canvas.QueueDraw()
+	}
+	dialog.Destroy()
+}
+
+func (app *App) apply() {
+	var args []string
+	for _, m := range app.monitors {
+		if m.Enabled {
+			args = append(args, "--output", m.Name, "--on", "--pos",
+				fmt.Sprintf("%d,%d", m.X, m.Y))
+		} else {
+			args = append(args, "--output", m.Name, "--off")
+		}
+	}
+	cmd := exec.Command("wlr-randr", args...)
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		log.Printf("wlr-randr error: %v\n%s", err, out)
+		dialog := gtk.MessageDialogNew(app.window, gtk.DIALOG_MODAL, gtk.MESSAGE_ERROR,
+			gtk.BUTTONS_OK, "wlr-randr failed: %s\n%s", err, string(out))
+		dialog.Run()
+		dialog.Destroy()
+	} else {
+		log.Printf("Applied: wlr-randr %s", strings.Join(args, " "))
+	}
+}
+
+func main() {
+	gtk.Init(nil)
+
+	app := &App{dragging: -1, scale: 0.15}
+
+	var err error
+	app.monitors, err = parseWlrRandr()
+	if err != nil {
+		log.Fatalf("Failed to parse wlr-randr: %v", err)
+	}
+
+	app.window, _ = gtk.WindowNew(gtk.WINDOW_TOPLEVEL)
+	app.window.SetTitle("wmon")
+	app.window.SetDefaultSize(900, 600)
+	app.window.Connect("destroy", gtk.MainQuit)
+
+	vbox, _ := gtk.BoxNew(gtk.ORIENTATION_VERTICAL, 0)
+	app.window.Add(vbox)
+
+	app.canvas, _ = gtk.DrawingAreaNew()
+	app.canvas.SetHExpand(true)
+	app.canvas.SetVExpand(true)
+	app.canvas.Connect("draw", app.draw)
+
+	app.canvas.AddEvents(int(gdk.BUTTON_PRESS_MASK | gdk.BUTTON_RELEASE_MASK |
+		gdk.POINTER_MOTION_MASK | gdk.SCROLL_MASK | gdk.SMOOTH_SCROLL_MASK))
+	app.canvas.Connect("button-press-event", func(da *gtk.DrawingArea, ev *gdk.Event) {
+		app.onPress(ev)
+	})
+	app.canvas.Connect("button-release-event", func(da *gtk.DrawingArea, ev *gdk.Event) {
+		app.onRelease(ev)
+	})
+	app.canvas.Connect("motion-notify-event", func(da *gtk.DrawingArea, ev *gdk.Event) {
+		app.onMotion(ev)
+	})
+	app.canvas.Connect("scroll-event", func(da *gtk.DrawingArea, ev *gdk.Event) {
+		app.onScroll(ev)
+	})
+
+	vbox.PackStart(app.canvas, true, true, 0)
+
+	btnBox, _ := gtk.BoxNew(gtk.ORIENTATION_HORIZONTAL, 5)
+	btnBox.SetMarginTop(5)
+	btnBox.SetMarginBottom(5)
+	btnBox.SetMarginStart(5)
+	btnBox.SetMarginEnd(5)
+
+	applyBtn, _ := gtk.ButtonNewWithLabel("Apply")
+	applyBtn.Connect("clicked", func() { app.apply() })
+
+	reloadBtn, _ := gtk.ButtonNewWithLabel("Reload")
+	reloadBtn.Connect("clicked", func() {
+		app.monitors, _ = parseWlrRandr()
+		app.layoutSet = false
+		app.canvas.QueueDraw()
+	})
+
+	btnBox.PackEnd(applyBtn, false, false, 0)
+	btnBox.PackEnd(reloadBtn, false, false, 0)
+
+	saveBtn, _ := gtk.ButtonNewWithLabel("Save")
+	saveBtn.Connect("clicked", func() { app.saveConfig() })
+	btnBox.PackStart(saveBtn, false, false, 0)
+
+	loadBtn, _ := gtk.ButtonNewWithLabel("Load")
+	loadBtn.Connect("clicked", func() { app.loadConfig() })
+	btnBox.PackStart(loadBtn, false, false, 0)
+
+	vbox.PackStart(btnBox, false, false, 0)
+
+	app.window.ShowAll()
+	gtk.Main()
+}