package gomod

import (
	"context"
	"fmt"
	"os"
	"os/exec"
	"regexp"
	"strings"

	"github.com/google/go-github/v53/github"
	"github.com/sirupsen/logrus"
	"golang.org/x/mod/modfile"
)

const (
	defaultVersion = "latest"
)

var githubRegexp = regexp.MustCompile(`github.com/(.*?)/(.*)`)

func upgrade(url string) (newUrl string, err error) {
	var version = defaultVersion
	if strings.Contains(url, "github.com") {
		commitID, err := getCommitID(url)
		if err != nil {
			logrus.WithField("url", url).Warnf("get github commit id failed, use default version: %v", err)
		} else {
			version = commitID
		}
	}

	if version == defaultVersion {
		v, err := lsRemote.setUrl(url).getLatestTagOrCommitID()
		if err != nil {
			logrus.WithField("url", url).Warnf("get git ls-remote info failed, use default version: %v", err)
		} else {
			version = v
		}
	}

	versionUrl := url + "@" + version
	cmd := exec.Command("go", "get", "-u", versionUrl)
	if _, err := cmd.CombinedOutput(); err != nil {
		return "", err
	}
	return versionUrl, nil
}

func AllModUpgrade() {
	modFileData, err := os.ReadFile("go.mod")
	if err != nil {
		logrus.Errorf("read go.mod file failed: %v", err)
		return
	}
	modFile, err := modfile.Parse("go.mod", modFileData, nil)
	if err != nil {
		logrus.Errorf("parse go.mod file failed: %v", err)
		return
	}
	for _, mod := range modFile.Require {
		if mod.Indirect {
			continue
		}
		versionUrl, err := upgrade(mod.Mod.Path)
		if err != nil {
			logrus.WithField("url", mod.Mod.Path).Errorf("upgrade failed: %v", err)
			continue
		}
		logrus.WithField("url", versionUrl).Infof("upgrade success")
	}
}

func SingleModUpgrade(url string) {
	versionUrl, err := upgrade(url)
	if err != nil {
		logrus.WithField("url", url).Errorf("upgrade failed: %v", err)
		return
	}
	logrus.WithField("url", versionUrl).Infof("upgrade success")
}

func parseUrl(url string) (owner, repo string) {
	res := githubRegexp.FindAllStringSubmatch(url, -1)
	if len(res) != 1 {
		logrus.Panicf(fmt.Sprintf("%s url no match github url rule: %s", url, githubRegexp.String()))
	}
	if len(res[0]) != 3 {
		logrus.Panicf(fmt.Sprintf("%s url no match github url rule: %s", url, githubRegexp.String()))
	}
	owner = res[0][1]
	repo = res[0][2]
	if repoA := strings.Split(repo, "/"); len(repoA) > 1 {
		repo = repoA[0]
	}
	return owner, repo
}

func getCommitID(url string) (string, error) {
	owner, repo := parseUrl(url)
	client := github.NewClient(nil)
	ctx := context.Background()
	tags, _, err := client.Repositories.ListTags(ctx, owner, repo, &github.ListOptions{
		Page:    0,
		PerPage: 1,
	})
	if err != nil {
		logrus.WithField("url", url).Warnf("get tag info failed: %v, start get commit id", err)
	}
	if len(tags) != 0 {
		return tags[0].GetName(), nil
	}
	// get latest commit id
	commits, _, err := client.Repositories.ListCommits(ctx, owner, repo, &github.CommitsListOptions{
		ListOptions: github.ListOptions{
			Page:    0,
			PerPage: 1,
		},
	})
	if err != nil {
		logrus.WithField("url", url).Errorf("get latest commit failed: %v", err)
		return "", err
	}
	if len(commits) == 0 {
		return "", fmt.Errorf("get commit info empty")
	}
	return *commits[0].SHA, nil
}