feat: set step loops with expression variable

uixt/types/field.go

@@ -0,0 +1,107 @@
+package types
+
+import (
+	"encoding/json"
+	"fmt"
+	"strconv"
+)
+
+// IntOrString supports int or string
+type IntOrString struct {
+	IntValue    *int    // e.g 513
+	StringValue *string // e.g "513", "$var"
+}
+
+// Value returns the int value, converting from string if necessary
+func (ios *IntOrString) Value() (int, error) {
+	if ios == nil {
+		return 0, nil
+	}
+
+	if ios.IntValue != nil {
+		return *ios.IntValue, nil
+	}
+	if ios.StringValue != nil {
+		if *ios.StringValue == "" {
+			return 0, nil
+		}
+		n, err := strconv.Atoi(*ios.StringValue)
+		if err != nil {
+			// variable expression, e.g. "$var"
+			return 0, err
+		}
+		return n, nil
+	}
+
+	// IntValue and StringValue are both nil
+	return 0, nil
+}
+
+// UnmarshalJSON implements custom JSON unmarshalling for IntOrString
+func (ios *IntOrString) UnmarshalJSON(data []byte) error {
+	// Try to unmarshal as int
+	var i int
+	if err := json.Unmarshal(data, &i); err == nil {
+		ios.IntValue = &i
+		ios.StringValue = nil
+		return nil
+	}
+	// Try to unmarshal as string
+	var s string
+	if err := json.Unmarshal(data, &s); err == nil {
+		ios.StringValue = &s
+		ios.IntValue = nil
+		return nil
+	}
+	return fmt.Errorf("invalid IntOrString data: %s", string(data))
+}
+
+// FloatOrString supports float64 or string
+type FloatOrString struct {
+	FloatValue  *float64 // e.g 5.13
+	StringValue *string  // e.g "5.13", "$var"
+}
+
+// Value returns the float value, converting from string if necessary
+func (ios *FloatOrString) Value() (float64, error) {
+	if ios == nil {
+		return 0, nil
+	}
+
+	if ios.FloatValue != nil {
+		return *ios.FloatValue, nil
+	}
+	if ios.StringValue != nil {
+		if *ios.StringValue == "" {
+			return 0, nil
+		}
+		n, err := strconv.ParseFloat(*ios.StringValue, 64)
+		if err != nil {
+			// variable expression, e.g. "$var"
+			return 0, err
+		}
+		return n, nil
+	}
+
+	// IntValue and StringValue are both nil
+	return 0, nil
+}
+
+// UnmarshalJSON implements custom JSON unmarshalling for IntOrString
+func (ios *FloatOrString) UnmarshalJSON(data []byte) error {
+	// Try to unmarshal as float
+	var f float64
+	if err := json.Unmarshal(data, &f); err == nil {
+		ios.FloatValue = &f
+		ios.StringValue = nil
+		return nil
+	}
+	// Try to unmarshal as string
+	var s string
+	if err := json.Unmarshal(data, &s); err == nil {
+		ios.StringValue = &s
+		ios.FloatValue = nil
+		return nil
+	}
+	return fmt.Errorf("invalid FloatOrString data: %s", string(data))
+}