1 files changed, 56 insertions, 9 deletions

diff --git a/form_input.go b/form_input.go
index 9576c98..41fe311 100644
--- a/form_input.go
+++ b/form_input.go
@@ -6,30 +6,77 @@ package trunks
 // FormInputKind define type for form input.
 type FormInputKind string
 
-// List of valid value for field FormInput.Kind.
+// List of valid value for field [FormInput] Kind.
 const (
 	// FormInputKindBoolean only used for convertion, for example
 	// ToJSONObject.
 	// In the WUI, it will be rendered as string.
 	FormInputKindBoolean = `boolean`
-	FormInputKindNumber  = `number`
-	FormInputKindString  = `string`
+
+	// FormInputKindFile define the input for uploading file.
+	// This form will rendered as "<input type='file' ...>" on the web
+	// user interface.
+	// Once submitted, the file name, type, size, and lastModification
+	// will be stored under [FormInput] Filename, Filetype, Filesize,
+	// and Filemodms.
+	FormInputKindFile = `file`
+
+	FormInputKindNumber = `number`
+	FormInputKindString = `string`
 )
 
 // FormInput provide the information to create an input component.
 //
-// The Label field define the input text, the Hint field provide a
-// description about the input, the Kind field describe the type of input
-// (number, string, and so on), and the Value field contains default value for
-// input.
+// The Label field define the input text.
+// The Hint field provide a description about the input.
+// The Kind field describe the type of input (number, string, and so on).
+// The Value field contains default value for input.
 //
 // The Max and Min fields is optional, it only affect if the Kind is
 // FormInputKindNumber.
+//
+// If the Kind is FormInputKindFile, the Filename, Filetype, Filesize, and
+// Filemodms will be filled by request based on the file name, type, size,
+// and modification time.
 type FormInput struct {
+	// FormDataName define function to map FormInputKindFile name
+	// into different name.
+	// For example, instead of,
+	//
+	//	Content-Disposition: form-data; name="filesize"
+	//
+	// One can change the "filesize" to "size" using this function, so
+	// generated request body would be,
+	//
+	//	Content-Disposition: form-data; name="size"
+	FormDataName func(string) string `json:"-"`
+
 	Label string        `json:"label"`
 	Hint  string        `json:"hint"`
 	Kind  FormInputKind `json:"kind"`
 	Value string        `json:"value"`
-	Max   float64       `json:"max,omitempty"`
-	Min   float64       `json:"min,omitempty"`
+
+	// The name of file for FormInputKindFile.
+	Filename string `json:"filename"`
+
+	Filetype string `json:"filetype"`
+
+	// The file size for FormInputKindFile.
+	Filesize int64 `json:"filesize"`
+
+	// The file modification in millisecond.
+	Filemodms int64 `json:"filemodms"`
+
+	Max float64 `json:"max,omitempty"`
+	Min float64 `json:"min,omitempty"`
+}
+
+func (fi *FormInput) init() {
+	if fi.FormDataName == nil {
+		fi.FormDataName = defaultFormDataName
+	}
+}
+
+func defaultFormDataName(in string) string {
+	return in
 }