package utils

import (
	"net/url"
	"strings"

	"github.com/pkg/errors"
)

// TypeLocal represents github
const TypeLocal = "local"

// TypeOss represent oss
const TypeOss = "oss"

// TypeGithub represents github
const TypeGithub = "github"

// TypeUnknown represents parse failed
const TypeUnknown = "unknown"

// Content contains different type of content needed when building Registry
type Content struct {
	OssContent
	GithubContent
	LocalContent
}

// LocalContent for local registry
type LocalContent struct {
	AbsDir string `json:"abs_dir"`
}

// OssContent for oss registry
type OssContent struct {
	BucketURL string `json:"bucket_url"`
}

// GithubContent for cap center
type GithubContent struct {
	Owner string `json:"owner"`
	Repo  string `json:"repo"`
	Path  string `json:"path"`
	Ref   string `json:"ref"`
}

// Parse will parse config from address
func Parse(addr string) (string, *Content, error) {
	URL, err := url.Parse(addr)
	if err != nil {
		return "", nil, err
	}
	l := strings.Split(strings.TrimPrefix(URL.Path, "/"), "/")
	switch URL.Scheme {
	case "http", "https":
		switch URL.Host {
		case "github.com":
			// We support two valid format:
			// 1. https://github.com/<owner>/<repo>/tree/<branch>/<path-to-dir>
			// 2. https://github.com/<owner>/<repo>/<path-to-dir>
			if len(l) < 3 {
				return "", nil, errors.New("invalid format " + addr)
			}
			if l[2] == "tree" {
				// https://github.com/<owner>/<repo>/tree/<branch>/<path-to-dir>
				if len(l) < 5 {
					return "", nil, errors.New("invalid format " + addr)
				}
				return TypeGithub, &Content{
					GithubContent: GithubContent{
						Owner: l[0],
						Repo:  l[1],
						Path:  strings.Join(l[4:], "/"),
						Ref:   l[3],
					},
				}, nil
			}
			// https://github.com/<owner>/<repo>/<path-to-dir>
			return TypeGithub, &Content{
					GithubContent: GithubContent{
						Owner: l[0],
						Repo:  l[1],
						Path:  strings.Join(l[2:], "/"),
						Ref:   "", // use default branch
					},
				},
				nil
		case "api.github.com":
			if len(l) != 5 {
				return "", nil, errors.New("invalid format " + addr)
			}
			//https://api.github.com/repos/<owner>/<repo>/contents/<path-to-dir>
			return TypeGithub, &Content{
					GithubContent: GithubContent{
						Owner: l[1],
						Repo:  l[2],
						Path:  l[4],
						Ref:   URL.Query().Get("ref"),
					},
				},
				nil
		default:
		}
	case "oss":
		return TypeOss, &Content{
			OssContent: OssContent{
				BucketURL: URL.Host,
			},
		}, nil
	case "file":
		return TypeLocal, &Content{
			LocalContent: LocalContent{
				AbsDir: URL.Path,
			},
		}, nil

	}

	return TypeUnknown, nil, nil
}