More custom-api additions/tweaks

* Remove need to convert to int for math stuff
* Add `now` and `duration` functions

docs/custom-api.md

@@ -226,10 +226,10 @@ JSON response:
 }
 ```
 
-Calculations can be performed, however all numbers must be converted to floats first if they are not already:
+Calculations can be performed on either ints or floats. If both numbers are ints, an int will be returned, otherwise a float will be returned. If you try to divide by zero, 0 will be returned. If you provide non-numeric values, `NaN` will be returned.
 
 ```html
-<div>{{ sub (.JSON.Int "price" | toFloat) (.JSON.Int "discount" | toFloat) }}</div>
+<div>{{ sub (.JSON.Int "price") (.JSON.Int "discount") }}</div>
 ```
 
 Output:
@@ -325,6 +325,8 @@ The following helper functions provided by Glance are available:
 - `toFloat(i int) float`: Converts an integer to a float.
 - `toInt(f float) int`: Converts a float to an integer.
 - `toRelativeTime(t time.Time) template.HTMLAttr`: Converts Time to a relative time such as 2h, 1d, etc which dynamically updates. **NOTE:** the value of this function should be used as an attribute in an HTML tag, e.g. `<span {{ toRelativeTime .Time }}></span>`.
+- `now() time.Time`: Returns the current time.
+- `duration(str string) time.Duration`: Parses a string such as `1h`, `1d`, `5h30m`, etc into a `time.Duration`.
 - `parseTime(layout string, s string) time.Time`: Parses a string into time.Time. The layout must be provided in Go's [date format](https://pkg.go.dev/time#pkg-constants). You can alternatively use these values instead of the literal format: "unix", "RFC3339", "RFC3339Nano", "DateTime", "DateOnly".
 - `parseRelativeTime(layout string, s string) time.Time`: A shorthand for `{{ .String "date" | parseTime "rfc3339" | toRelativeTime }}`.
 - `add(a, b float) float`: Adds two numbers.

internal/glance/widget-custom-api.go

@@ -342,6 +342,23 @@ func (r *decoratedGJSONResult) Bool(key string) bool {
 	return r.Get(key).Bool()
 }
 
+func customAPIDoMathOp[T int | float64](a, b T, op string) T {
+	switch op {
+	case "add":
+		return a + b
+	case "sub":
+		return a - b
+	case "mul":
+		return a * b
+	case "div":
+		if b == 0 {
+			return 0
+		}
+		return a / b
+	}
+	return 0
+}
+
 var customAPITemplateFuncs = func() template.FuncMap {
 	var regexpCacheMu sync.Mutex
 	var regexpCache = make(map[string]*regexp.Regexp)
@@ -359,6 +376,31 @@ var customAPITemplateFuncs = func() template.FuncMap {
 		return regex
 	}
 
+	doMathOpWithAny := func(a, b any, op string) any {
+		switch at := a.(type) {
+		case int:
+			switch bt := b.(type) {
+			case int:
+				return customAPIDoMathOp(at, bt, op)
+			case float64:
+				return customAPIDoMathOp(float64(at), bt, op)
+			default:
+				return math.NaN()
+			}
+		case float64:
+			switch bt := b.(type) {
+			case int:
+				return customAPIDoMathOp(at, float64(bt), op)
+			case float64:
+				return customAPIDoMathOp(at, bt, op)
+			default:
+				return math.NaN()
+			}
+		default:
+			return math.NaN()
+		}
+	}
+
 	funcs := template.FuncMap{
 		"toFloat": func(a int) float64 {
 			return float64(a)
@@ -366,21 +408,28 @@ var customAPITemplateFuncs = func() template.FuncMap {
 		"toInt": func(a float64) int {
 			return int(a)
 		},
-		"add": func(a, b float64) float64 {
-			return a + b
+		"add": func(a, b any) any {
+			return doMathOpWithAny(a, b, "add")
 		},
-		"sub": func(a, b float64) float64 {
-			return a - b
+		"sub": func(a, b any) any {
+			return doMathOpWithAny(a, b, "sub")
 		},
-		"mul": func(a, b float64) float64 {
-			return a * b
+		"mul": func(a, b any) any {
+			return doMathOpWithAny(a, b, "mul")
 		},
-		"div": func(a, b float64) float64 {
-			if b == 0 {
-				return math.NaN()
+		"div": func(a, b any) any {
+			return doMathOpWithAny(a, b, "div")
+		},
+		"now": func() time.Time {
+			return time.Now()
+		},
+		"duration": func(str string) time.Duration {
+			d, err := time.ParseDuration(str)
+			if err != nil {
+				return 0
 			}
 
-			return a / b
+			return d
 		},
 		"parseTime":      customAPIFuncParseTime,
 		"toRelativeTime": dynamicRelativeTimeAttrs,