// Copyright © 2013 Steve Francia <spf@spf13.com>.
//
// Licensed under the Simple Public License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://opensource.org/licenses/Simple-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package helpers

import (
	"net/url"
	"regexp"
	"strings"
	"unicode"
)

var sanitizeRegexp = regexp.MustCompile("[^a-zA-Z0-9./_-]")

func MakePath(s string) string {
	return unicodeSanitize(strings.ToLower(strings.Replace(strings.TrimSpace(s), " ", "-", -1)))
}

func Urlize(uri string) string {
	sanitized := MakePath(uri)

	// escape unicode letters
	parsedUri, err := url.Parse(sanitized)
	if err != nil {
		// if net/url can not parse URL it's meaning Sanitize works incorrect
		panic(err)
	}
	return parsedUri.String()
}

func Sanitize(s string) string {
	return sanitizeRegexp.ReplaceAllString(s, "")
}

func unicodeSanitize(s string) string {
	source := []rune(s)
	target := make([]rune, 0, len(source))

	for _, r := range source {
		if unicode.IsLetter(r) || unicode.IsDigit(r) || r == '.' || r == '/' || r == '_' || r == '-' {
			target = append(target, r)
		}
	}

	return string(target)
}