Fs02/grimoire

package changeset

import (
    "strconv"
    "strings"
)

// ValidateMaxErrorMessage is the default error message for ValidateMax.
var ValidateMaxErrorMessage = "{field} must be less than {max}"

// ValidateMax validates the value of given field is not larger than max.
// Validation can be performed against string, slice and numbers.
func ValidateMax(ch *Changeset, field string, max int, opts ...Option) {
    val, exist := ch.changes[field]
    if !exist {
        return
    }

    options := Options{
        message: ValidateMaxErrorMessage,
    }
    options.apply(opts)

    invalid := false

    switch v := val.(type) {
    case string:
        invalid = len(v) > max
    case []interface{}:
        invalid = len(v) > max
    case []*Changeset:
        invalid = len(v) > max
    case int:
        invalid = v > max
    case int8:
        invalid = v > int8(max)
    case int16:
        invalid = v > int16(max)
    case int32:
        invalid = v > int32(max)
    case int64:
        invalid = v > int64(max)
    case uint:
        invalid = v > uint(max)
    case uint8:
        invalid = v > uint8(max)
    case uint16:
        invalid = v > uint16(max)
    case uint32:
        invalid = v > uint32(max)
    case uint64:
        invalid = v > uint64(max)
    case uintptr:
        invalid = v > uintptr(max)
    case float32:
        invalid = v > float32(max)
    case float64:
        invalid = v > float64(max)
    }

    if invalid {
        r := strings.NewReplacer("{field}", field, "{max}", strconv.Itoa(max))
        AddError(ch, field, r.Replace(options.message))
    }
}