Big Refactor (#2)

Refactor Everything.

Co-authored-by: Anna Rose Wiggins <annabunches@gmail.com>
Co-committed-by: Anna Rose Wiggins <annabunches@gmail.com>

cmd/joyful/main.go

@@ -75,7 +75,7 @@ func main() {
 
 	timerCount := 0
 	for _, rule := range rules {
-		if timedRule, ok := rule.(*mappingrules.MappingRuleProportionalAxis); ok {
+		if timedRule, ok := rule.(*mappingrules.MappingRuleAxisToButton); ok {
 			go timerWatcher(timedRule, eventChannel)
 			timerCount++
 		}

cmd/joyful/threads.go

@@ -28,7 +28,7 @@ func eventWatcher(device *evdev.InputDevice, channel chan<- ChannelEvent) {
 	}
 }
 
-func timerWatcher(rule *mappingrules.MappingRuleProportionalAxis, channel chan<- ChannelEvent) {
+func timerWatcher(rule *mappingrules.MappingRuleAxisToButton, channel chan<- ChannelEvent) {
 	for {
 		event := rule.TimerEvent()
 		if event != nil {

internal/config/make_rule_targets.go

@@ -0,0 +1,56 @@
+package config
+
+import (
+	"errors"
+	"fmt"
+
+	"git.annabunches.net/annabunches/joyful/internal/mappingrules"
+	"github.com/holoplot/go-evdev"
+)
+
+func makeRuleTargetButton(targetConfig RuleTargetConfig, devs map[string]*evdev.InputDevice) (*mappingrules.RuleTargetButton, error) {
+	device, ok := devs[targetConfig.Device]
+	if !ok {
+		return nil, fmt.Errorf("non-existent device '%s'", targetConfig.Device)
+	}
+
+	eventCode, ok := evdev.KEYFromString[targetConfig.Button]
+	if !ok {
+		return nil, fmt.Errorf("invalid button code '%s'", targetConfig.Button)
+	}
+
+	return mappingrules.NewRuleTargetButton(
+		targetConfig.Device,
+		device,
+		eventCode,
+		targetConfig.Inverted,
+	), nil
+}
+
+func makeRuleTargetAxis(targetConfig RuleTargetConfig, devs map[string]*evdev.InputDevice) (*mappingrules.RuleTargetAxis, error) {
+	device, ok := devs[targetConfig.Device]
+	if !ok {
+		return nil, fmt.Errorf("non-existent device '%s'", targetConfig.Device)
+	}
+
+	eventCode, ok := evdev.ABSFromString[targetConfig.Axis]
+	if !ok {
+		return nil, fmt.Errorf("invalid button code '%s'", targetConfig.Button)
+	}
+
+	return mappingrules.NewRuleTargetAxis(
+		targetConfig.Device,
+		device,
+		eventCode,
+		targetConfig.Inverted,
+		0, 0, 0, // TODO: replace these with real values
+	), nil
+}
+
+func makeRuleTargetModeSelect(targetConfig RuleTargetConfig, allModes []string) (*mappingrules.RuleTargetModeSelect, error) {
+	if ok := validateModes(targetConfig.Modes, allModes); !ok {
+		return nil, errors.New("undefined mode in mode select list")
+	}
+
+	return mappingrules.NewRuleTargetModeSelect(targetConfig.Modes)
+}

internal/config/make_rules.go

@@ -1,8 +1,8 @@
 package config
 
 import (
+	"errors"
 	"fmt"
-	"slices"
 	"strings"
 
 	"git.annabunches.net/annabunches/joyful/internal/logger"
@@ -23,23 +23,32 @@ func (parser *ConfigParser) BuildRules(pDevs map[string]*evdev.InputDevice, vDev
 		var newRule mappingrules.MappingRule
 		var err error
 
-		baseParams, err := setBaseRuleParameters(ruleConfig, modes)
-		if err != nil {
-			logger.LogErrorf(err, "couldn't set output parameters, skipping rule '%s'", ruleConfig.Name)
+		if ok := validateModes(ruleConfig.Modes, modes); !ok {
+			logger.Logf("Skipping rule '%s', mode list specifies undefined mode.", ruleConfig.Name)
 			continue
 		}
 
+		base := mappingrules.NewMappingRuleBase(ruleConfig.Name, ruleConfig.Modes)
+
 		switch strings.ToLower(ruleConfig.Type) {
-		case RuleTypeSimple:
-			newRule, err = makeMappingRuleButton(ruleConfig, pDevs, vDevs, baseParams)
-		case RuleTypeCombo:
-			newRule, err = makeComboRule(ruleConfig, pDevs, vDevs, baseParams)
+		case RuleTypeButton:
+			newRule, err = makeMappingRuleButton(ruleConfig, pDevs, vDevs, base)
+		case RuleTypeButtonCombo:
+			newRule, err = makeMappingRuleCombo(ruleConfig, pDevs, vDevs, base)
 		case RuleTypeLatched:
-			newRule, err = makeLatchedRule(ruleConfig, pDevs, vDevs, baseParams)
+			newRule, err = makeMappingRuleLatched(ruleConfig, pDevs, vDevs, base)
+		case RuleTypeAxis:
+			newRule, err = makeMappingRuleAxis(ruleConfig, pDevs, vDevs, base)
+		case RuleTypeAxisToButton:
+			newRule, err = makeMappingRuleAxisToButton(ruleConfig, pDevs, vDevs, base)
+		case RuleTypeModeSelect:
+			newRule, err = makeMappingRuleModeSelect(ruleConfig, pDevs, modes, base)
+		default:
+			err = fmt.Errorf("bad rule type '%s' for rule '%s'", ruleConfig.Type, ruleConfig.Name)
 		}
 
 		if err != nil {
-			logger.LogError(err, "failed to build rule")
+			logger.LogErrorf(err, "Failed to build rule '%s'", ruleConfig.Name)
 			continue
 		}
 
@@ -49,56 +58,28 @@ func (parser *ConfigParser) BuildRules(pDevs map[string]*evdev.InputDevice, vDev
 	return rules
 }
 
-func setBaseRuleParameters(ruleConfig RuleConfig, modes []string) (mappingrules.MappingRuleBase, error) {
-	// We perform this check here instead of in makeRuleTarget because only Output targets
-	// can meaningfully have ModeSelect; this lets us avoid plumbing the modes in on every
-	// makeRuleTarget call.
-	if len(ruleConfig.Output.ModeSelect) > 0 {
-		err := validateModes(ruleConfig.Output.ModeSelect, modes)
-		if err != nil {
-			return mappingrules.MappingRuleBase{}, err
-		}
-	}
-
-	err := validateModes(ruleConfig.Modes, modes)
-	if err != nil {
-		return mappingrules.MappingRuleBase{}, err
-	}
-
-	ruleModes := ensureModes(ruleConfig.Modes)
-
-	return mappingrules.MappingRuleBase{
-		Modes: ruleModes,
-		Name:  ruleConfig.Name,
-	}, nil
-}
-
 func makeMappingRuleButton(ruleConfig RuleConfig,
 	pDevs map[string]*evdev.InputDevice,
 	vDevs map[string]*evdev.InputDevice,
 	base mappingrules.MappingRuleBase) (*mappingrules.MappingRuleButton, error) {
 
-	input, err := makeRuleTarget(ruleConfig.Input, pDevs)
+	input, err := makeRuleTargetButton(ruleConfig.Input, pDevs)
 	if err != nil {
 		return nil, err
 	}
 
-	output, err := makeRuleTarget(ruleConfig.Output, vDevs)
+	output, err := makeRuleTargetButton(ruleConfig.Output, vDevs)
 	if err != nil {
 		return nil, err
 	}
 
-	return &mappingrules.MappingRuleButton{
-		MappingRuleBase: base,
-		Input:           input.(*mappingrules.RuleTargetButton),
-		Output:          output.(*mappingrules.RuleTargetButton),
-	}, nil
+	return mappingrules.NewMappingRuleButton(base, input, output), nil
 }
 
-func makeComboRule(ruleConfig RuleConfig,
+func makeMappingRuleCombo(ruleConfig RuleConfig,
 	pDevs map[string]*evdev.InputDevice,
 	vDevs map[string]*evdev.InputDevice,
-	base mappingrules.MappingRuleBase) (*mappingrules.MappingRuleCombo, error) {
+	base mappingrules.MappingRuleBase) (*mappingrules.MappingRuleButtonCombo, error) {
 
 	inputs := make([]*mappingrules.RuleTargetButton, 0)
 	for _, inputConfig := range ruleConfig.Inputs {
@@ -109,142 +90,73 @@ func makeComboRule(ruleConfig RuleConfig,
 		inputs = append(inputs, input)
 	}
 
-	return &mappingrules.MappingRuleCombo{
-		MappingRuleBase: base,
-		Inputs:          inputs,
-		State:           0,
-	}, nil
+	output, err := makeRuleTargetButton(ruleConfig.Output, vDevs)
+	if err != nil {
+		return nil, err
+	}
+
+	return mappingrules.NewMappingRuleButtonCombo(base, inputs, output), nil
 }
 
-func makeLatchedRule(ruleConfig RuleConfig,
+func makeMappingRuleLatched(ruleConfig RuleConfig,
 	pDevs map[string]*evdev.InputDevice,
 	vDevs map[string]*evdev.InputDevice,
-	base mappingrules.MappingRuleBase) (*mappingrules.MappingRuleLatched, error) {
+	base mappingrules.MappingRuleBase) (*mappingrules.MappingRuleButtonLatched, error) {
 
 	input, err := makeRuleTargetButton(ruleConfig.Input, pDevs)
 	if err != nil {
 		return nil, err
 	}
 
-	return &mappingrules.MappingRuleLatched{
-		MappingRuleBase: base,
-		Input:           input,
-		State:           false,
-	}, nil
-}
-
-func makeRuleTargetButton(targetConfig RuleTargetConfig, devs map[string]*evdev.InputDevice) (*mappingrules.RuleTargetButton, error) {
-	device, ok := devs[targetConfig.Device]
-	if !ok {
-		return nil, fmt.Errorf("couldn't build rule due to non-existent device '%s'", targetConfig.Device)
-	}
-
-	_, eventCode, err := decodeRuleTargetValues(targetConfig)
+	output, err := makeRuleTargetButton(ruleConfig.Output, vDevs)
 	if err != nil {
 		return nil, err
 	}
 
-	baseParams := mappingrules.RuleTargetBase{
-		DeviceName: targetConfig.Device,
-		Device:     device,
-		Inverted:   targetConfig.Inverted,
-		Code:       eventCode,
-	}
-
-	return &mappingrules.RuleTargetButton{
-		RuleTargetBase: baseParams,
-	}, nil
+	return mappingrules.NewMappingRuleButtonLatched(base, input, output), nil
 }
 
-// makeRuleTarget takes an Input declaration from the YAML and returns a fully formed RuleTarget.
-func makeRuleTarget(targetConfig RuleTargetConfig, devs map[string]*evdev.InputDevice) (mappingrules.RuleTarget, error) {
-	if len(targetConfig.ModeSelect) > 0 {
-		return &mappingrules.RuleTargetModeSelect{
-			ModeSelect: targetConfig.ModeSelect,
-		}, nil
-	}
+func makeMappingRuleAxis(ruleConfig RuleConfig,
+	pDevs map[string]*evdev.InputDevice,
+	vDevs map[string]*evdev.InputDevice,
+	base mappingrules.MappingRuleBase) (*mappingrules.MappingRuleAxis, error) {
 
-	device, ok := devs[targetConfig.Device]
-	if !ok {
-		return nil, fmt.Errorf("couldn't build rule due to non-existent device '%s'", targetConfig.Device)
-	}
-
-	eventType, eventCode, err := decodeRuleTargetValues(targetConfig)
+	input, err := makeRuleTargetAxis(ruleConfig.Input, pDevs)
 	if err != nil {
 		return nil, err
 	}
 
-	baseParams := mappingrules.RuleTargetBase{
-		DeviceName: targetConfig.Device,
-		Device:     device,
-		Inverted:   targetConfig.Inverted,
-		Code:       eventCode,
+	output, err := makeRuleTargetAxis(ruleConfig.Output, vDevs)
+	if err != nil {
+		return nil, err
 	}
 
-	switch eventType {
-	case evdev.EV_KEY:
-		return &mappingrules.RuleTargetButton{
-			RuleTargetBase: baseParams,
-		}, nil
-
-	case evdev.EV_ABS:
-		return &mappingrules.RuleTargetAxis{
-			RuleTargetBase: baseParams,
-			AxisStart:      targetConfig.AxisStart,
-			AxisEnd:        targetConfig.AxisEnd,
-		}, nil
-
-	default:
-		return nil, fmt.Errorf("skipping rule due to unsupported event type '%d'", eventType)
-	}
+	return mappingrules.NewMappingRuleAxis(base, input, output), nil
 }
 
-// decodeRuleTargetValues returns the appropriate evdev.EvType and evdev.EvCode values
-// for a given RuleTargetConfig, converting the config file strings into appropriate constants
-//
-// Todo: support different formats for key specification
-func decodeRuleTargetValues(target RuleTargetConfig) (evdev.EvType, evdev.EvCode, error) {
-	var eventType evdev.EvType
-	var eventCode evdev.EvCode
-	var ok bool
+// STUB
+func makeMappingRuleAxisToButton(ruleConfig RuleConfig,
+	pDevs map[string]*evdev.InputDevice,
+	vDevs map[string]*evdev.InputDevice,
+	base mappingrules.MappingRuleBase) (*mappingrules.MappingRuleAxisToButton, error) {
 
-	if target.Button != "" {
-		eventType = evdev.EV_KEY
-		eventCode, ok = evdev.KEYFromString[target.Button]
-		if !ok {
-			return 0, 0, fmt.Errorf("skipping rule due to invalid button code '%s'", target.Button)
-		}
-	} else if target.Axis != "" {
-		eventType = evdev.EV_ABS
-		eventCode, ok = evdev.ABSFromString[target.Axis]
-		if !ok {
-			return 0, 0, fmt.Errorf("skipping rule due to invalid axis code '%s'", target.Button)
-		}
-	}
-
-	return eventType, eventCode, nil
+	return nil, errors.New("stub: makeMappingRuleAxisToButton")
 }
 
-// ensureModes either returns the mode list, or if it is empty returns []string{"*"}
-func ensureModes(modes []string) []string {
-	if len(modes) == 0 {
-		return []string{"*"}
+func makeMappingRuleModeSelect(ruleConfig RuleConfig,
+	pDevs map[string]*evdev.InputDevice,
+	modes []string,
+	base mappingrules.MappingRuleBase) (*mappingrules.MappingRuleModeSelect, error) {
+
+	input, err := makeRuleTargetButton(ruleConfig.Input, pDevs)
+	if err != nil {
+		return nil, err
 	}
-	return modes
-}
-
-// validateModes checks the provided modes against a larger subset of modes (usually all defined ones)
-// and returns an error if any of the modes are not defined.
-func validateModes(modes []string, allModes []string) error {
-	if len(modes) == 0 {
-		return nil
-	}
-
-	for _, mode := range modes {
-		if !slices.Contains(allModes, mode) {
-			return fmt.Errorf("mode list specifies undefined mode '%s'", mode)
-		}
-	}
-
-	return nil
+
+	output, err := makeRuleTargetModeSelect(ruleConfig.Output, modes)
+	if err != nil {
+		return nil, err
+	}
+
+	return mappingrules.NewMappingRuleModeSelect(base, input, output), nil
 }

internal/config/modes.go

@@ -0,0 +1,19 @@
+package config
+
+import "slices"
+
+// validateModes checks the provided modes against a larger subset of modes (usually all defined ones)
+// and returns false if any of the modes are not defined.
+func validateModes(modes []string, allModes []string) bool {
+	if len(modes) == 0 {
+		return true
+	}
+
+	for _, mode := range modes {
+		if !slices.Contains(allModes, mode) {
+			return false
+		}
+	}
+
+	return true
+}

internal/config/schema.go

@@ -28,11 +28,11 @@ type RuleConfig struct {
 }
 
 type RuleTargetConfig struct {
-	Device     string   `yaml:"device,omitempty"`
-	Button     string   `yaml:"button,omitempty"`
-	Axis       string   `yaml:"axis,omitempty"`
-	AxisStart  int32    `yaml:"axis_start,omitempty"`
-	AxisEnd    int32    `yaml:"axis_end,omitempty"`
-	Inverted   bool     `yaml:"inverted,omitempty"`
-	ModeSelect []string `yaml:"mode_select,omitempty"`
+	Device        string   `yaml:"device,omitempty"`
+	Button        string   `yaml:"button,omitempty"`
+	Axis          string   `yaml:"axis,omitempty"`
+	DeadzoneStart int32    `yaml:"axis_start,omitempty"`
+	DeadzoneEnd   int32    `yaml:"axis_end,omitempty"`
+	Inverted      bool     `yaml:"inverted,omitempty"`
+	Modes         []string `yaml:"modes,omitempty"`
 }

internal/config/variables.go

@@ -4,6 +4,18 @@ import (
 	"github.com/holoplot/go-evdev"
 )
 
+const (
+	DeviceTypePhysical = "physical"
+	DeviceTypeVirtual  = "virtual"
+
+	RuleTypeButton       = "button"
+	RuleTypeButtonCombo  = "button-combo"
+	RuleTypeLatched      = "button-latched"
+	RuleTypeAxis         = "axis"
+	RuleTypeModeSelect   = "mode-select"
+	RuleTypeAxisToButton = "axis-to-button"
+)
+
 var (
 	ButtonFromIndex = []evdev.EvCode{
 		evdev.BTN_TRIGGER,
@@ -60,12 +72,3 @@ var (
 		evdev.BTN_TRIGGER_HAPPY40,
 	}
 )
-
-const (
-	DeviceTypePhysical = "physical"
-	DeviceTypeVirtual  = "virtual"
-
-	RuleTypeSimple = "simple"
-	RuleTypeCombo  = "combo"
-	RuleTypeLatched = "latched"
-)

internal/logger/logger.go

@@ -25,7 +25,7 @@ func LogErrorf(err error, msg string, params ...interface{}) {
 	if msg == "" {
 		fmt.Printf("%s\n", err.Error())
 	} else {
-		fmt.Printf("%s: %s\n", err.Error(), fmt.Sprintf(msg, params...))
+		fmt.Printf("%s: %s\n", fmt.Sprintf(msg, params...), err.Error())
 	}
 }
 

internal/mappingrules/interfaces.go

@@ -13,11 +13,16 @@ type RuleTarget interface {
 	// (e.g., inverting the value if Inverted == true)
 	NormalizeValue(int32) int32
 
-	// CreateEvent typically takes the (probably normalized) value and returns an event that can be emitted
-	// on a virtual device.
-	//
+	// MatchEvent returns true if the provided device and input event are a match for this rule target
+	ValidateEvent(*evdev.InputDevice, *evdev.InputEvent) bool
+
+	// CreateEvent creates an event that can be emitted on a virtual device.
 	// For RuleTargetModeSelect, this method modifies the active mode and returns nil.
 	//
-	// TODO: should we normalize inside this function to simplify the interface?
+	// CreateEvent does not do any error checking; it assumes it is receiving verified and sanitized output.
+	// The caller is responsible for determining whether an event *should* be emitted.
+	//
+	// Typically int32 is the input event's normalized value. *string is the current mode, but is optional
+	// for most implementations.
 	CreateEvent(int32, *string) *evdev.InputEvent
 }

internal/mappingrules/mapping_rule_axis.go

@@ -0,0 +1,27 @@
+package mappingrules
+
+import "github.com/holoplot/go-evdev"
+
+// A Simple Mapping Rule can map a button to a button or an axis to an axis.
+type MappingRuleAxis struct {
+	MappingRuleBase
+	Input  *RuleTargetAxis
+	Output *RuleTargetAxis
+}
+
+func NewMappingRuleAxis(base MappingRuleBase, input *RuleTargetAxis, output *RuleTargetAxis) *MappingRuleAxis {
+	return &MappingRuleAxis{
+		MappingRuleBase: base,
+		Input:           input,
+		Output:          output,
+	}
+}
+
+func (rule *MappingRuleAxis) MatchEvent(device *evdev.InputDevice, event *evdev.InputEvent, mode *string) (*evdev.InputDevice, *evdev.InputEvent) {
+	if !rule.MappingRuleBase.modeCheck(mode) ||
+		!rule.Input.MatchEvent(device, event) {
+		return nil, nil
+	}
+
+	return rule.Output.Device, rule.Output.CreateEvent(rule.Input.NormalizeValue(event.Value), mode)
+}

internal/mappingrules/mapping_rule_axis_to_button.go

@@ -0,0 +1,51 @@
+package mappingrules
+
+import (
+	"time"
+
+	"github.com/holoplot/go-evdev"
+)
+
+// TODO: This whole file is still WIP
+type MappingRuleAxisToButton struct {
+	MappingRuleBase
+	Input          *RuleTargetAxis
+	Output         *RuleTargetButton
+	RepeatSpeedMin int32
+	RepeatSpeedMax int32
+	lastValue      int32
+	lastEvent      time.Time
+}
+
+func (rule *MappingRuleAxisToButton) MatchEvent(device *evdev.InputDevice, event *evdev.InputEvent, mode *string) (*evdev.InputDevice, *evdev.InputEvent) {
+	if !rule.MappingRuleBase.modeCheck(mode) ||
+		!rule.Input.MatchEvent(device, event) {
+		return nil, nil
+	}
+
+	// set the last value to the normalized input value
+	rule.lastValue = rule.Input.NormalizeValue(event.Value)
+	return nil, nil
+}
+
+// TimerEvent returns an event when enough time has passed (compared to the last recorded axis value)
+// to emit an event.
+func (rule *MappingRuleAxisToButton) TimerEvent() *evdev.InputEvent {
+	// This is tighter coupling than we'd like, but it will do for now.
+	// TODO: maybe it would be better to just be more declarative about event types and their inputs and outputs.
+	if rule.lastValue < rule.Input.DeadzoneStart {
+		rule.lastEvent = time.Now()
+		return nil
+	}
+
+	// calculate target time until next event press
+	//	nextEvent := rule.LastEvent + (rule.LastValue)
+
+	// TODO: figure out what the condition should be
+	if false {
+		// TODO: emit event
+		rule.lastEvent = time.Now()
+	}
+
+	return nil
+}

internal/mappingrules/mapping_rule_base.go

@@ -7,6 +7,20 @@ type MappingRuleBase struct {
 	Modes []string
 }
 
+func NewMappingRuleBase(
+	name string,
+	modes []string,
+) MappingRuleBase {
+	if len(modes) == 0 {
+		modes = []string{"*"}
+	}
+
+	return MappingRuleBase{
+		Name:  name,
+		Modes: modes,
+	}
+}
+
 func (rule *MappingRuleBase) modeCheck(mode *string) bool {
 	if rule.Modes[0] == "*" {
 		return true

internal/mappingrules/mapping_rule_button.go

@@ -9,13 +9,25 @@ type MappingRuleButton struct {
 	Output *RuleTargetButton
 }
 
+func NewMappingRuleButton(
+	base MappingRuleBase,
+	input *RuleTargetButton,
+	output *RuleTargetButton) *MappingRuleButton {
+
+	return &MappingRuleButton{
+		MappingRuleBase: base,
+		Input:           input,
+		Output:          output,
+	}
+}
+
 func (rule *MappingRuleButton) MatchEvent(device *evdev.InputDevice, event *evdev.InputEvent, mode *string) (*evdev.InputDevice, *evdev.InputEvent) {
 	if !rule.MappingRuleBase.modeCheck(mode) {
 		return nil, nil
 	}
 
-	if device != rule.Input.GetDevice() ||
-		event.Code != rule.Input.GetCode() {
+	if device != rule.Input.Device ||
+		event.Code != rule.Input.Button {
 		return nil, nil
 	}
 

internal/mappingrules/mapping_rule_button_combo.go

@@ -3,24 +3,37 @@ package mappingrules
 import "github.com/holoplot/go-evdev"
 
 // A Combo Mapping Rule can require multiple physical button presses for a single output button
-type MappingRuleCombo struct {
+type MappingRuleButtonCombo struct {
 	MappingRuleBase
 	Inputs []*RuleTargetButton
 	Output *RuleTargetButton
 	State  int
 }
 
-func (rule *MappingRuleCombo) MatchEvent(device *evdev.InputDevice, event *evdev.InputEvent, mode *string) (*evdev.InputDevice, *evdev.InputEvent) {
+func NewMappingRuleButtonCombo(
+	base MappingRuleBase,
+	inputs []*RuleTargetButton,
+	output *RuleTargetButton) *MappingRuleButtonCombo {
+
+	return &MappingRuleButtonCombo{
+		MappingRuleBase: base,
+		Inputs:          inputs,
+		Output:          output,
+		State:           0,
+	}
+}
+
+func (rule *MappingRuleButtonCombo) MatchEvent(device *evdev.InputDevice, event *evdev.InputEvent, mode *string) (*evdev.InputDevice, *evdev.InputEvent) {
 	if !rule.MappingRuleBase.modeCheck(mode) {
 		return nil, nil
 	}
 
 	// Check each of the inputs, and if we find a match, proceed
-	var match RuleTarget
+	var match *RuleTargetButton
 	for _, input := range rule.Inputs {
-		if device == input.GetDevice() &&
-			event.Code == input.GetCode() {
+		if input.MatchEvent(device, event) {
 			match = input
+			break
 		}
 	}
 
@@ -40,10 +53,10 @@ func (rule *MappingRuleCombo) MatchEvent(device *evdev.InputDevice, event *evdev
 	targetState := len(rule.Inputs)
 
 	if oldState == targetState-1 && rule.State == targetState {
-		return rule.Output.GetDevice(), rule.Output.CreateEvent(1, mode)
+		return rule.Output.Device, rule.Output.CreateEvent(1, mode)
 	}
 	if oldState == targetState && rule.State == targetState-1 {
-		return rule.Output.GetDevice(), rule.Output.CreateEvent(0, mode)
+		return rule.Output.Device, rule.Output.CreateEvent(0, mode)
 	}
 	return nil, nil
 }

internal/mappingrules/mapping_rule_button_latched.go

@@ -2,20 +2,33 @@ package mappingrules
 
 import "github.com/holoplot/go-evdev"
 
-type MappingRuleLatched struct {
+type MappingRuleButtonLatched struct {
 	MappingRuleBase
 	Input  *RuleTargetButton
 	Output *RuleTargetButton
 	State  bool
 }
 
-func (rule *MappingRuleLatched) MatchEvent(device *evdev.InputDevice, event *evdev.InputEvent, mode *string) (*evdev.InputDevice, *evdev.InputEvent) {
+func NewMappingRuleButtonLatched(
+	base MappingRuleBase,
+	input *RuleTargetButton,
+	output *RuleTargetButton) *MappingRuleButtonLatched {
+
+	return &MappingRuleButtonLatched{
+		MappingRuleBase: base,
+		Input:           input,
+		Output:          output,
+		State:           false,
+	}
+}
+
+func (rule *MappingRuleButtonLatched) MatchEvent(device *evdev.InputDevice, event *evdev.InputEvent, mode *string) (*evdev.InputDevice, *evdev.InputEvent) {
 	if !rule.MappingRuleBase.modeCheck(mode) {
 		return nil, nil
 	}
 
 	if device != rule.Input.Device ||
-		event.Code != rule.Input.Code ||
+		event.Code != rule.Input.Button ||
 		rule.Input.NormalizeValue(event.Value) == 0 {
 		return nil, nil
 	}

internal/mappingrules/mapping_rule_mode_select.go

@@ -0,0 +1,40 @@
+package mappingrules
+
+import "github.com/holoplot/go-evdev"
+
+type MappingRuleModeSelect struct {
+	MappingRuleBase
+	Input  *RuleTargetButton
+	Output *RuleTargetModeSelect
+}
+
+func NewMappingRuleModeSelect(
+	base MappingRuleBase,
+	input *RuleTargetButton,
+	output *RuleTargetModeSelect,
+) *MappingRuleModeSelect {
+
+	return &MappingRuleModeSelect{
+		MappingRuleBase: base,
+		Input:           input,
+		Output:          output,
+	}
+}
+
+func (rule *MappingRuleModeSelect) MatchEvent(
+	device *evdev.InputDevice,
+	event *evdev.InputEvent,
+	mode *string) (*evdev.InputDevice, *evdev.InputEvent) {
+
+	if !rule.MappingRuleBase.modeCheck(mode) {
+		return nil, nil
+	}
+
+	if device != rule.Input.Device ||
+		event.Code != rule.Input.Button ||
+		rule.Input.NormalizeValue(event.Value) == 0 {
+		return nil, nil
+	}
+
+	return nil, rule.Output.CreateEvent(event.Value, mode)
+}

internal/mappingrules/mapping_rule_proportional_axis.go

@@ -1,54 +0,0 @@
-package mappingrules
-
-import (
-	"time"
-
-	"github.com/holoplot/go-evdev"
-)
-
-// TODO: How are we going to implement this? It needs to operate on a timer...
-type MappingRuleProportionalAxis struct {
-	MappingRuleBase
-	Input       *RuleTargetAxis
-	Output      *RuleTargetButton
-	Sensitivity int32
-	LastValue   int32
-	LastEvent   time.Time
-}
-
-func (rule *MappingRuleProportionalAxis) MatchEvent(device *evdev.InputDevice, event *evdev.InputEvent, mode *string) (*evdev.InputDevice, *evdev.InputEvent) {
-	if !rule.MappingRuleBase.modeCheck(mode) {
-		return nil, nil
-	}
-
-	if device != rule.Input.GetDevice() ||
-		event.Code != rule.Input.GetCode() {
-		return nil, nil
-	}
-
-	// set the last value to the normalized input value
-	rule.LastValue = rule.Input.NormalizeValue(event.Value)
-	return nil, nil
-}
-
-// TimerEvent returns an event when enough time has passed (compared to the last recorded axis value)
-// to emit an event.
-func (rule *MappingRuleProportionalAxis) TimerEvent() *evdev.InputEvent {
-	// This is tighter coupling than we'd like, but it will do for now.
-	// TODO: maybe it would be better to just be more declarative about event types and their inputs and outputs.
-	if rule.LastValue < rule.Input.AxisStart {
-		rule.LastEvent = time.Now()
-		return nil
-	}
-
-	// calculate target time until next event press
-	//	nextEvent := rule.LastEvent + (rule.LastValue)
-
-	// TODO: figure out what the condition should be
-	if false {
-		// TODO: emit event
-		rule.LastEvent = time.Now()
-	}
-
-	return nil
-}

internal/mappingrules/rule_target_axis.go

@@ -5,35 +5,43 @@ import (
 )
 
 type RuleTargetAxis struct {
-	RuleTargetBase
-	AxisStart   int32
-	AxisEnd     int32
-	Sensitivity float64
+	DeviceName    string
+	Device        *evdev.InputDevice
+	Axis          evdev.EvCode
+	Inverted      bool
+	DeadzoneStart int32
+	DeadzoneEnd   int32
+	Sensitivity   float64
 }
 
 func NewRuleTargetAxis(device_name string,
 	device *evdev.InputDevice,
-	code evdev.EvCode,
+	axis evdev.EvCode,
 	inverted bool,
-	axis_start int32,
-	axis_end int32,
+	deadzone_start int32,
+	deadzone_end int32,
 	sensitivity float64) *RuleTargetAxis {
 
 	return &RuleTargetAxis{
-		RuleTargetBase: NewRuleTargetBase(device_name, device, code, inverted),
-		AxisStart:      axis_start,
-		AxisEnd:        axis_end,
-		Sensitivity:    sensitivity,
+		DeviceName:    device_name,
+		Device:        device,
+		Axis:          axis,
+		Inverted:      inverted,
+		DeadzoneStart: deadzone_start,
+		DeadzoneEnd:   deadzone_end,
+		Sensitivity:   sensitivity,
 	}
 }
 
+// TODO: lots of fixes and decisions to make here. Should we normalize all axes to the same range?
+// How do we handle deadzones in light of that?
 func (target *RuleTargetAxis) NormalizeValue(value int32) int32 {
 	if !target.Inverted {
 		return value
 	}
 
-	axisRange := target.AxisEnd - target.AxisStart
-	axisMid := target.AxisEnd - axisRange/2
+	axisRange := target.DeadzoneEnd - target.DeadzoneStart
+	axisMid := target.DeadzoneEnd - axisRange/2
 	delta := value - axisMid
 	if delta < 0 {
 		delta = -delta
@@ -55,7 +63,13 @@ func (target *RuleTargetAxis) CreateEvent(value int32, mode *string) *evdev.Inpu
 	// TODO: oh no we need center deadzones actually...
 	return &evdev.InputEvent{
 		Type:  evdev.EV_ABS,
-		Code:  target.Code,
+		Code:  target.Axis,
 		Value: value,
 	}
 }
+
+func (target *RuleTargetAxis) MatchEvent(device *evdev.InputDevice, event *evdev.InputEvent) bool {
+	return device == target.Device &&
+		event.Type == evdev.EV_ABS &&
+		event.Code == target.Axis
+}

internal/mappingrules/rule_target_base.go

@@ -1,35 +0,0 @@
-package mappingrules
-
-import "github.com/holoplot/go-evdev"
-
-type RuleTargetBase struct {
-	DeviceName string
-	Device     *evdev.InputDevice
-	Code       evdev.EvCode
-	Inverted   bool
-}
-
-func NewRuleTargetBase(device_name string,
-	device *evdev.InputDevice,
-	code evdev.EvCode,
-	inverted bool) RuleTargetBase {
-
-	return RuleTargetBase{
-		DeviceName: device_name,
-		Device:     device,
-		Code:       code,
-		Inverted:   inverted,
-	}
-}
-
-func (target *RuleTargetBase) GetCode() evdev.EvCode {
-	return target.Code
-}
-
-func (target *RuleTargetBase) GetDeviceName() string {
-	return target.DeviceName
-}
-
-func (target *RuleTargetBase) GetDevice() *evdev.InputDevice {
-	return target.Device
-}

internal/mappingrules/rule_target_button.go

@@ -3,12 +3,18 @@ package mappingrules
 import "github.com/holoplot/go-evdev"
 
 type RuleTargetButton struct {
-	RuleTargetBase
+	DeviceName string
+	Device     *evdev.InputDevice
+	Button     evdev.EvCode
+	Inverted   bool
 }
 
 func NewRuleTargetButton(device_name string, device *evdev.InputDevice, code evdev.EvCode, inverted bool) *RuleTargetButton {
 	return &RuleTargetButton{
-		RuleTargetBase: NewRuleTargetBase(device_name, device, code, inverted),
+		DeviceName: device_name,
+		Device:     device,
+		Button:     code,
+		Inverted:   inverted,
 	}
 }
 
@@ -22,10 +28,16 @@ func (target *RuleTargetButton) NormalizeValue(value int32) int32 {
 	return value
 }
 
-func (target *RuleTargetButton) CreateEvent(value int32, mode *string) *evdev.InputEvent {
+func (target *RuleTargetButton) CreateEvent(value int32, _ *string) *evdev.InputEvent {
 	return &evdev.InputEvent{
 		Type:  evdev.EV_KEY,
-		Code:  target.Code,
+		Code:  target.Button,
 		Value: value,
 	}
 }
+
+func (target *RuleTargetButton) MatchEvent(device *evdev.InputDevice, event *evdev.InputEvent) bool {
+	return device == target.Device &&
+		event.Type == evdev.EV_KEY &&
+		event.Code == target.Button
+}

internal/mappingrules/rule_target_modeselect.go

@@ -1,6 +1,7 @@
 package mappingrules
 
 import (
+	"errors"
 	"slices"
 
 	"git.annabunches.net/annabunches/joyful/internal/logger"
@@ -8,34 +9,35 @@ import (
 )
 
 type RuleTargetModeSelect struct {
-	RuleTargetBase
-	ModeSelect []string
+	Modes []string
 }
 
-func NewRuleTargetModeSelect(modes []string) *RuleTargetModeSelect {
-	return &RuleTargetModeSelect{
-		RuleTargetBase: NewRuleTargetBase("", nil, 0, false),
-		ModeSelect:     modes,
+func NewRuleTargetModeSelect(modes []string) (*RuleTargetModeSelect, error) {
+	if len(modes) == 0 {
+		return nil, errors.New("cannot create RuleTargetModeSelect: mode list is empty")
 	}
+	return &RuleTargetModeSelect{
+		Modes: modes,
+	}, nil
 }
 
 // RuleTargetModeSelect doesn't make sense as an input type
-func (target *RuleTargetModeSelect) NormalizeValue(value int32) int32 {
+func (target *RuleTargetModeSelect) NormalizeValue(_ int32) int32 {
 	return -1
 }
 
-func (target *RuleTargetModeSelect) CreateEvent(value int32, mode *string) *evdev.InputEvent {
-	if value == 0 {
-		return nil
-	}
-
+func (target *RuleTargetModeSelect) CreateEvent(_ int32, mode *string) *evdev.InputEvent {
 	index := 0
-	if currentMode := slices.Index(target.ModeSelect, *mode); currentMode != -1 {
+	if currentMode := slices.Index(target.Modes, *mode); currentMode != -1 {
 		// find the next mode
-		index = (currentMode + 1) % len(target.ModeSelect)
+		index = (currentMode + 1) % len(target.Modes)
 	}
 
-	*mode = target.ModeSelect[index]
+	*mode = target.Modes[index]
 	logger.Logf("Mode changed to '%s'", *mode)
 	return nil
 }
+
+func (target *RuleTargetModeSelect) MatchEvent(_ *evdev.InputDevice, _ *evdev.InputEvent) bool {
+	return false
+}