feat: support named switchable layouts

BUILD.md

@@ -231,8 +231,10 @@ to bypass that boundary or request elevation through a manifest.
 ### Configuration reload
 
 The YAML decoder rejects unknown fields. Semantic validation checks the schema
-version, gap range, unique monitor entries, zone bounds, hotkey action syntax,
+version, gap range, active-layout existence, unique layout-name/monitor pairs,
-and required values.
+zone bounds, hotkey action syntax, and required values. Legacy files in which
+all layouts are unnamed and `active_layout` is absent are normalized to a
+single layout name of `default` before validation.
 
 The message-loop timer checks the configuration modification time. A valid new
 configuration replaces the active one and re-registers hotkeys. If parsing,

README.md

@@ -79,15 +79,17 @@ Here is a complete two-column configuration:
 version: 1
 gap: 8
 shift_drag: true
+active_layout: columns
 
 overlay:
   enabled: true
   color: "#00AEEF"
   opacity: 90
-  border_width: 3
+  border_width: 10
 
 layouts:
-  - monitor: "*"
+  - name: columns
+    monitor: "*"
     zones:
       - name: left
         x: 0
@@ -100,6 +102,15 @@ layouts:
         width: 50
         height: 100
 
+  - name: fullscreen
+    monitor: "*"
+    zones:
+      - name: full
+        x: 0
+        y: 0
+        width: 100
+        height: 100
+
 excluded_apps:
   - mstsc.exe
 
@@ -126,6 +137,7 @@ use.
 | `version` | Configuration format. This must currently be `1`. |
 | `gap` | Inward spacing, in pixels, applied to every edge of every zone. Valid range: `0`–`500`. |
 | `shift_drag` | Enables or disables mouse snapping when Shift is held at the end of a drag. |
+| `active_layout` | Name of the layout currently used for snapping and the overlay. |
 | `overlay` | Controls the transparent zone guide shown during Shift-dragging. |
 | `layouts` | One or more monitor layouts containing zones. |
 | `excluded_apps` | Applications FancyWin must not move. May be empty. |
@@ -144,7 +156,7 @@ overlay:
   enabled: true
   color: "#00AEEF"
   opacity: 90
-  border_width: 3
+  border_width: 10
 ```
 
 - `enabled` turns the guide on or off.
@@ -182,7 +194,32 @@ For example, the bottom-right quarter is:
 Zones may overlap. If the pointer is inside more than one zone, the first
 matching zone listed in the file is selected.
 
-### Monitor-specific layouts
+### Named layouts and monitor-specific variants
+
+Every entry under `layouts` has a `name`. Set `active_layout` to that name to
+choose which layout FancyWin uses:
+
+```yaml
+active_layout: focus
+
+layouts:
+  - name: focus
+    monitor: "*"
+    zones:
+      - { name: left, x: 0, y: 0, width: 25, height: 100 }
+      - { name: middle, x: 25, y: 0, width: 50, height: 100 }
+      - { name: right, x: 75, y: 0, width: 25, height: 100 }
+
+  - name: equal-thirds
+    monitor: "*"
+    zones:
+      - { name: left, x: 0, y: 0, width: 33.333, height: 100 }
+      - { name: middle, x: 33.333, y: 0, width: 33.334, height: 100 }
+      - { name: right, x: 66.667, y: 0, width: 33.333, height: 100 }
+```
+
+Changing `active_layout` to `equal-thirds` is applied automatically within
+about two seconds; FancyWin does not need to be restarted.
 
 Use `monitor: "*"` as the fallback layout for every display that does not have
 a specific entry. At startup, FancyWin prints detected device names such as
@@ -192,18 +229,25 @@ A specific monitor layout can override the fallback:
 
 ```yaml
 layouts:
-  - monitor: "*"
+  - name: focus
+    monitor: "*"
     zones:
       - { name: left,  x: 0,  y: 0, width: 50, height: 100 }
       - { name: right, x: 50, y: 0, width: 50, height: 100 }
 
-  - monitor: '\\.\DISPLAY2'
+  - name: focus
+    monitor: '\\.\DISPLAY2'
     zones:
       - { name: main, x: 0,  y: 0, width: 70, height: 100 }
       - { name: side, x: 70, y: 0, width: 30, height: 100 }
 ```
 
-Only one layout may be declared for each monitor name.
+The monitor-specific entry must use the same layout name as its fallback. Only
+one entry may be declared for each combination of layout name and monitor name.
+Names and monitor matching are not case-sensitive.
+
+Older configurations containing no `active_layout` and no layout names are
+loaded as one backwards-compatible layout named `default`.
 
 ### Hotkeys
 

cmd/fancywin/main.go

@@ -11,7 +11,7 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
-const version = "0.2.1"
+const version = "0.3.0"
 
 func main() {
 	exe, err := os.Executable()

fancywin.example.yaml

@@ -3,16 +3,18 @@
 version: 1
 gap: 8
 shift_drag: true
+active_layout: focus
 
 overlay:
   enabled: true
   color: "#00AEEF"
   opacity: 90
-  border_width: 3
+  border_width: 10
 
 layouts:
   # The wildcard is used for any monitor without a more specific entry.
-  - monitor: "*"
+  - name: focus
+    monitor: "*"
     zones:
       - name: left
         x: 0
@@ -30,9 +32,19 @@ layouts:
         width: 25
         height: 100
 
+  # Other layouts remain available by name. Change active_layout above to
+  # switch layouts; a running FancyWin instance reloads the change.
+  - name: equal-thirds
+    monitor: "*"
+    zones:
+      - { name: left, x: 0, y: 0, width: 33.333, height: 100 }
+      - { name: middle, x: 33.333, y: 0, width: 33.334, height: 100 }
+      - { name: right, x: 66.667, y: 0, width: 33.333, height: 100 }
+
   # Optional per-display override. Get the name from Windows Display Settings
   # or the startup diagnostics, then uncomment and edit this block.
-  # - monitor: '\\.\DISPLAY2'
+  # - name: focus
+  #   monitor: '\\.\DISPLAY2'
   #   zones:
   #     - { name: main, x: 0, y: 0, width: 70, height: 100 }
   #     - { name: side, x: 70, y: 0, width: 30, height: 100 }

internal/config/config.go

@@ -15,6 +15,7 @@ type Config struct {
 	Version      int      `yaml:"version"`
 	Gap          int      `yaml:"gap"`
 	ShiftDrag    bool     `yaml:"shift_drag"`
+	ActiveLayout string   `yaml:"active_layout"`
 	Overlay      Overlay  `yaml:"overlay"`
 	Layouts      []Layout `yaml:"layouts"`
 	Excluded     []string `yaml:"excluded_apps"`
@@ -29,6 +30,7 @@ type Overlay struct {
 }
 
 type Layout struct {
+	Name    string `yaml:"name"`
 	Monitor string `yaml:"monitor"`
 	Zones   []Zone `yaml:"zones"`
 }
@@ -49,8 +51,9 @@ type Hotkey struct {
 func Default() Config {
 	return Config{
 		Version: 1, Gap: 8, ShiftDrag: true,
-		Overlay: Overlay{Enabled: true, Color: "#00AEEF", Opacity: 90, BorderWidth: 3},
+		ActiveLayout: "columns",
-		Layouts: []Layout{{Monitor: "*", Zones: []Zone{
+		Overlay:      Overlay{Enabled: true, Color: "#00AEEF", Opacity: 90, BorderWidth: 10},
+		Layouts: []Layout{{Name: "columns", Monitor: "*", Zones: []Zone{
 			{Name: "left", X: 0, Y: 0, Width: 50, Height: 100},
 			{Name: "right", X: 50, Y: 0, Width: 50, Height: 100},
 		}}},
@@ -73,6 +76,7 @@ func Load(path string) (Config, error) {
 	if err := d.Decode(&c); err != nil {
 		return Config{}, fmt.Errorf("parse YAML: %w", err)
 	}
+	c.upgradeLegacyLayouts()
 	if err := c.Validate(); err != nil {
 		return Config{}, err
 	}
@@ -100,15 +104,27 @@ func (c Config) Validate() error {
 	if len(c.Layouts) == 0 {
 		return errors.New("at least one layout is required")
 	}
+	active := strings.TrimSpace(c.ActiveLayout)
+	if active == "" {
+		return errors.New("active_layout is required")
+	}
 	seenMonitors := map[string]bool{}
+	activeExists := false
 	for li, l := range c.Layouts {
+		layoutName := strings.TrimSpace(l.Name)
+		if layoutName == "" {
+			return fmt.Errorf("layouts[%d].name is required", li)
+		}
+		if strings.EqualFold(layoutName, active) {
+			activeExists = true
+		}
 		name := strings.TrimSpace(l.Monitor)
 		if name == "" {
 			return fmt.Errorf("layouts[%d].monitor is required", li)
 		}
-		key := strings.ToLower(name)
+		key := strings.ToLower(layoutName) + "\x00" + strings.ToLower(name)
 		if seenMonitors[key] {
-			return fmt.Errorf("duplicate layout for monitor %q", name)
+			return fmt.Errorf("duplicate layout named %q for monitor %q", layoutName, name)
 		}
 		seenMonitors[key] = true
 		if len(l.Zones) == 0 {
@@ -120,6 +136,9 @@ func (c Config) Validate() error {
 			}
 		}
 	}
+	if !activeExists {
+		return fmt.Errorf("active_layout %q does not match any layout name", c.ActiveLayout)
+	}
 	for i, h := range c.Hotkeys {
 		a := strings.ToLower(strings.TrimSpace(h.Action))
 		if a != "next_zone" && a != "previous_zone" && !strings.HasPrefix(a, "zone_") {
@@ -138,6 +157,21 @@ func (c Config) Validate() error {
 	return nil
 }
 
+func (c *Config) upgradeLegacyLayouts() {
+	if strings.TrimSpace(c.ActiveLayout) != "" || len(c.Layouts) == 0 {
+		return
+	}
+	for _, l := range c.Layouts {
+		if strings.TrimSpace(l.Name) != "" {
+			return
+		}
+	}
+	c.ActiveLayout = "default"
+	for i := range c.Layouts {
+		c.Layouts[i].Name = "default"
+	}
+}
+
 func validHexColor(s string) bool {
 	if len(s) != 7 || s[0] != '#' {
 		return false
@@ -151,14 +185,15 @@ func DefaultPath(exePath string) string {
 }
 
 func (c Config) LayoutFor(device string) (Layout, bool) {
+	active := strings.TrimSpace(c.ActiveLayout)
 	for _, l := range c.Layouts {
 		monitor := strings.TrimSpace(l.Monitor)
-		if monitor != "*" && strings.EqualFold(monitor, strings.TrimSpace(device)) {
+		if strings.EqualFold(strings.TrimSpace(l.Name), active) && monitor != "*" && strings.EqualFold(monitor, strings.TrimSpace(device)) {
 			return l, true
 		}
 	}
 	for _, l := range c.Layouts {
-		if strings.TrimSpace(l.Monitor) == "*" {
+		if strings.EqualFold(strings.TrimSpace(l.Name), active) && strings.TrimSpace(l.Monitor) == "*" {
 			return l, true
 		}
 	}

internal/config/config_test.go

@@ -1,6 +1,10 @@
 package config
 
-import "testing"
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
 
 func TestDefaultValid(t *testing.T) {
 	if err := Default().Validate(); err != nil {
@@ -15,6 +19,51 @@ func TestLayoutFallback(t *testing.T) {
 	}
 }
 
+func TestActiveLayoutSelection(t *testing.T) {
+	c := Default()
+	c.Layouts = append(c.Layouts, Layout{Name: "wide", Monitor: "*", Zones: []Zone{{Name: "wide", Width: 100, Height: 100}}})
+	c.ActiveLayout = "wide"
+	got, ok := c.LayoutFor(`\\.\DISPLAY1`)
+	if !ok || got.Name != "wide" || len(got.Zones) != 1 {
+		t.Fatalf("wrong active layout: %+v, %v", got, ok)
+	}
+}
+
+func TestLegacyLayoutUpgrade(t *testing.T) {
+	c := Default()
+	c.ActiveLayout = ""
+	for i := range c.Layouts {
+		c.Layouts[i].Name = ""
+	}
+	c.upgradeLegacyLayouts()
+	if c.ActiveLayout != "default" || c.Layouts[0].Name != "default" {
+		t.Fatalf("legacy layout was not upgraded: %+v", c)
+	}
+}
+
+func TestLoadLegacyUnnamedLayout(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "legacy.yaml")
+	data := []byte("version: 1\ngap: 8\nshift_drag: true\nlayouts:\n  - monitor: '*'\n    zones:\n      - {x: 0, y: 0, width: 100, height: 100}\n")
+	if err := os.WriteFile(path, data, 0o600); err != nil {
+		t.Fatal(err)
+	}
+	c, err := Load(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if c.ActiveLayout != "default" || c.Layouts[0].Name != "default" {
+		t.Fatalf("legacy file was not upgraded: %+v", c)
+	}
+}
+
+func TestMissingActiveLayoutFails(t *testing.T) {
+	c := Default()
+	c.ActiveLayout = "missing"
+	if err := c.Validate(); err == nil {
+		t.Fatal("expected missing active layout to fail")
+	}
+}
+
 func TestExcluded(t *testing.T) {
 	c := Default()
 	c.Excluded = []string{"notepad", "exact.exe"}

internal/platform/platform_windows.go

@@ -168,7 +168,7 @@ func Run(configPath string, cfg config.Config, debug bool) error {
 	}
 	defer procKillTimer.Call(0, shiftTimer)
 
-	log.Printf("ready: Shift+drag snapping=%v, overlay=%v, %d hotkeys", cfg.ShiftDrag, cfg.Overlay.Enabled, len(e.hotkeys))
+	log.Printf("ready: layout=%q, Shift+drag snapping=%v, overlay=%v, %d hotkeys", cfg.ActiveLayout, cfg.ShiftDrag, cfg.Overlay.Enabled, len(e.hotkeys))
 	logMonitors()
 	var msg message
 	for {
@@ -419,7 +419,7 @@ func (e *engine) snapAtCursor(hwnd windows.Handle) (bool, string) {
 	e.mu.RUnlock()
 	l, ok := cfg.LayoutFor(mi.device())
 	if !ok {
-		return false, fmt.Sprintf("no layout matches monitor %s and no wildcard layout exists", mi.device())
+		return false, fmt.Sprintf("active layout %q has no entry for monitor %s and no wildcard fallback", cfg.ActiveLayout, mi.device())
 	}
 	work := toLayoutRect(mi.Work)
 	zi := layout.ZoneAt(work, l.Zones, 0, layout.Point{X: p.X, Y: p.Y})
@@ -690,5 +690,5 @@ func (e *engine) reloadIfChanged() {
 		_ = e.registerHotkeys()
 		return
 	}
-	log.Printf("configuration reloaded")
+	log.Printf("configuration reloaded: active layout=%q", cfg.ActiveLayout)
 }