Use Survey For Interactions With User (#186)

fixes

Use Survey For Interactions With User

Add Vendor "github.com/AlecAivazis/survey/v2"

Co-authored-by: Norwin Roosen <git@nroo.de>
Co-authored-by: 6543 <6543@obermui.de>
Reviewed-on: https://gitea.com/gitea/tea/pulls/186
Reviewed-by: techknowlogick <techknowlogick@gitea.io>
Reviewed-by: Norwin <noerw@noreply.gitea.io>

vendor/github.com/AlecAivazis/survey/v2/validate.go

@@ -0,0 +1,87 @@
+package survey
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+)
+
+// Required does not allow an empty value
+func Required(val interface{}) error {
+	// the reflect value of the result
+	value := reflect.ValueOf(val)
+
+	// if the value passed in is the zero value of the appropriate type
+	if isZero(value) && value.Kind() != reflect.Bool {
+		return errors.New("Value is required")
+	}
+	return nil
+}
+
+// MaxLength requires that the string is no longer than the specified value
+func MaxLength(length int) Validator {
+	// return a validator that checks the length of the string
+	return func(val interface{}) error {
+		if str, ok := val.(string); ok {
+			// if the string is longer than the given value
+			if len([]rune(str)) > length {
+				// yell loudly
+				return fmt.Errorf("value is too long. Max length is %v", length)
+			}
+		} else {
+			// otherwise we cannot convert the value into a string and cannot enforce length
+			return fmt.Errorf("cannot enforce length on response of type %v", reflect.TypeOf(val).Name())
+		}
+
+		// the input is fine
+		return nil
+	}
+}
+
+// MinLength requires that the string is longer or equal in length to the specified value
+func MinLength(length int) Validator {
+	// return a validator that checks the length of the string
+	return func(val interface{}) error {
+		if str, ok := val.(string); ok {
+			// if the string is shorter than the given value
+			if len([]rune(str)) < length {
+				// yell loudly
+				return fmt.Errorf("value is too short. Min length is %v", length)
+			}
+		} else {
+			// otherwise we cannot convert the value into a string and cannot enforce length
+			return fmt.Errorf("cannot enforce length on response of type %v", reflect.TypeOf(val).Name())
+		}
+
+		// the input is fine
+		return nil
+	}
+}
+
+// ComposeValidators is a variadic function used to create one validator from many.
+func ComposeValidators(validators ...Validator) Validator {
+	// return a validator that calls each one sequentially
+	return func(val interface{}) error {
+		// execute each validator
+		for _, validator := range validators {
+			// if the answer's value is not valid
+			if err := validator(val); err != nil {
+				// return the error
+				return err
+			}
+		}
+		// we passed all validators, the answer is valid
+		return nil
+	}
+}
+
+// isZero returns true if the passed value is the zero object
+func isZero(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Slice, reflect.Map:
+		return v.Len() == 0
+	}
+
+	// compare the types directly with more general coverage
+	return reflect.DeepEqual(v.Interface(), reflect.Zero(v.Type()).Interface())
+}