package repos

import (
    "encoding/json"
    "errors"
    "os"
    "path/filepath"
    "strings"
)

type Repo struct {
    URL   string `json:"url"`
    Owner string `json:"owner"`
    Name  string `json:"name"`
}

func configPath() (string, error) {
    home, err := os.UserHomeDir()
    if err != nil {
        return "", err
    }

    dir := filepath.Join(home, ".config", "ginie")
    os.MkdirAll(dir, 0755)

    return filepath.Join(dir, "repos.json"), nil
}

func LoadRepos() ([]Repo, error) {
    path, err := configPath()
    if err != nil {
        return nil, err
    }

    data, err := os.ReadFile(path)
    if os.IsNotExist(err) {
        return []Repo{}, nil
    }
    if err != nil {
        return nil, err
    }

    var repos []Repo
    err = json.Unmarshal(data, &repos)
    if err != nil {
        return nil, err
    }

    return repos, nil
}

func SaveRepos(repos []Repo) error {
    path, err := configPath()
    if err != nil {
        return err
    }

    data, err := json.MarshalIndent(repos, "", "  ")
    if err != nil {
        return err
    }

    return os.WriteFile(path, data, 0644)
}

func ParseGitHubURL(raw string) (Repo, error) {
    if !strings.HasPrefix(raw, "https://github.com/") {
        return Repo{}, errors.New("URL ist kein gültiger GitHub-Link")
    }

    parts := strings.Split(strings.TrimPrefix(raw, "https://github.com/"), "/")
    if len(parts) < 2 {
        return Repo{}, errors.New("GitHub-Link hat nicht das Format: https://github.com/<owner>/<repo>")
    }

    return Repo{
        URL:   raw,
        Owner: parts[0],
        Name:  parts[1],
    }, nil
}

func AddRepo(url string) error {
    repo, err := ParseGitHubURL(url)
    if err != nil {
        return err
    }

    repos, err := LoadRepos()
    if err != nil {
        return err
    }

    // prüfen ob bereits vorhanden
    for _, r := range repos {
        if r.URL == repo.URL {
            return errors.New("Repo existiert bereits")
        }
    }

    repos = append(repos, repo)

    return SaveRepos(repos)
}

func RemoveRepo(url string) error {
	repos, err := LoadRepos()
	if err != nil {
		return err
	}

	index := -1
	for i, r := range repos {
		if r.URL == url {
			index = i
			break
		}
	}

	if index == -1 {
		return errors.New("Repo nicht gefunden")
	}

	repos = append(repos[:index], repos[index+1:]...)

	return SaveRepos(repos)
}

func ListRepos() ([]Repo, error) {
    return LoadRepos()
}