initial commit

model_position_change.go

@@ -0,0 +1,61 @@
+package niri
+
+import (
+	"encoding/json"
+	"fmt"
+	"regexp"
+	"strconv"
+)
+
+type PositionChange struct {
+	SetFixed    Option[int] `json:"SetFixed,omitempty"`
+	AdjustFixed Option[int] `json:"AdjustFixed,omitempty"`
+}
+
+func (m PositionChange) String() string {
+	data, _ := json.MarshalIndent(m, "", "\t")
+	return string(data)
+}
+
+func PositionSetFixed(position int) PositionChange {
+	return PositionChange{SetFixed: &position}
+}
+
+func PositionAdjustFixed(position int) PositionChange {
+	return PositionChange{AdjustFixed: &position}
+}
+
+const positionPatternString = `^(\+|-)?(\d+?)$`
+const positionPatternGroupAdjust = 1
+const positionPatternGroupIntValue = 2
+
+var positionPattern = regexp.MustCompile(positionPatternString)
+
+func ParsePosition(str string) (PositionChange, error) {
+	matches := positionPattern.FindStringSubmatch(str)
+	if matches == nil {
+		return PositionChange{}, fmt.Errorf("invalid position spec '%s'. Expected pattern: %s", str, positionPatternString)
+	}
+
+	adjust := matches[positionPatternGroupAdjust] != ""
+	negative := matches[positionPatternGroupAdjust] == "-"
+
+	factor := 1
+	if negative {
+		factor = -1
+	}
+
+	intValue, err := strconv.ParseInt(matches[positionPatternGroupIntValue], 10, 64)
+	if err != nil {
+		return PositionChange{}, fmt.Errorf("invalid position spec '%s'. Expected pattern: %s", str, positionPatternString)
+	}
+
+	switch true {
+	case adjust:
+		return PositionAdjustFixed(int(intValue) * factor), nil
+	case !adjust:
+		return PositionSetFixed(int(intValue) * factor), nil
+	default:
+		return PositionChange{}, fmt.Errorf("invalid position spec '%s'. Expected pattern: %s", str, positionPatternString)
+	}
+}