package common

/*
 * This file is part of Autogits.
 *
 * Copyright © 2024 SUSE LLC
 *
 * Autogits is free software: you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation, either version 2 of the License, or (at your option) any later
 * version.
 *
 * Autogits is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * Foobar. If not, see <https://www.gnu.org/licenses/>.
 */

import (
	"fmt"
	"net/url"
	"regexp"
	"slices"
	"strings"
)

func SplitLines(str string) []string {
	return SplitStringNoEmpty(str, "\n")
}

func SplitStringNoEmpty(str, sep string) []string {
	ret := slices.DeleteFunc(strings.Split(str, sep), func(s string) bool {
		return len(strings.TrimSpace(s)) == 0
	})
	for i := range ret {
		ret[i] = strings.TrimSpace(ret[i])
	}
	return ret
}

func TranslateHttpsToSshUrl(url string) (string, error) {
	const (
		url1 = "https://src.opensuse.org/"
		url2 = "https://src.suse.de/"

		url1_len = len(url1)
		url2_len = len(url2)
	)

	if len(url) > url1_len && url[0:url1_len] == url1 {
		return "ssh://gitea@src.opensuse.org/" + url[url1_len:], nil
	}
	if len(url) > url2_len && url[0:url2_len] == url2 {
		return "ssh://gitea@src.suse.de/" + url[url2_len:], nil
	}

	return "", fmt.Errorf("Unknown input url %s", url)
}

func TranslateSshNativeToUrl(urlString string) (string, error) {
	rx := regexp.MustCompile("^([^:@]+)@?([^:]*):(.+)$")
	m := rx.FindAllStringSubmatch(urlString, -1)
	if m == nil {
		return "", fmt.Errorf("Cannot match expected native SSH schema: %s", urlString)
	}

	if len(m[0][2]) > 0 {
		// with user
		return "ssh://" + m[0][1] + "@" + m[0][2] + "/" + m[0][3], nil
	}
	// without user
	return "ssh://" + m[0][1] + "/" + m[0][3], nil
}

type GitUrl struct {
	Org    string
	Repo   string
	Commit string
}

var valid_schemas []string = []string { "https", "ssh", "http" }

func ParseGitRemoteUrl(urlString string) (*GitUrl, error) {
	url, err := url.Parse(urlString)
	if err != nil || !slices.Contains(valid_schemas, url.Scheme) {
		u, err := TranslateSshNativeToUrl(urlString)
		if err != nil {
			return nil, fmt.Errorf("Unable to parse url: %w", err)
		}
		return ParseGitRemoteUrl(u)
	}

	e := SplitStringNoEmpty(url.Path, "/")
	if len(e) != 2 {
		return nil, fmt.Errorf("Unexpected format for Gitea URL: %s", e)
	}

	org := e[0]
	repo := e[1]
	if len(repo) > 4 && repo[len(repo)-4:] == ".git" {
		repo = repo[0 : len(repo)-4]
	}

	u := GitUrl{
		Org:    org,
		Repo:   repo,
		Commit: url.Fragment,
	}

	return &u, nil
}