package manifest

import (
	"encoding/json"
	"errors"
	"fmt"
	"io/ioutil"
	"net/http"
	"train/pkg/config"
)

type BinaryInfo struct {
	URL      string `json:"url"`
	Checksum string `json:"checksum"`
}

type Manifest struct {
	Name         string                `json:"name"`
	Version      string                `json:"version"`
	Mode         string                `json:"mode"`
	Source       string                `json:"source"`
	Checksum     string                `json:"checksum"`
	Dependencies []string              `json:"dependencies"`
	Build        []string              `json:"build"`
	Binaries     map[string]BinaryInfo `json:"binaries"`
	Uninstall    []string              `json:"uninstall"`
}

func FetchManifest(name string) (*Manifest, error) {
	cfg, err := config.LoadConfig()
	if err != nil {
		return nil, err
	}
	if url, ok := cfg.Packages[name]; ok {
		return fetchManifestFromURL(url)
	}
	var lastErr error
	for _, repo := range cfg.Repositories {
		url := fmt.Sprintf("%s/%s/manifest.json", repo, name)
		m, err := fetchManifestFromURL(url)
		if err == nil {
			return m, nil
		}
		lastErr = err
	}
	if lastErr == nil {
		lastErr = errors.New("не найден ни один репозиторий")
	}
	return nil, lastErr
}

func fetchManifestFromURL(url string) (*Manifest, error) {
	resp, err := http.Get(url)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()
	if resp.StatusCode != 200 {
		return nil, errors.New("манифест пакета не найден по ссылке " + url)
	}
	data, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}
	var m Manifest
	if err := json.Unmarshal(data, &m); err != nil {
		return nil, err
	}
	return &m, nil
}