feat: begin github support

github/updater.go

@@ -0,0 +1,102 @@
+package github
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"github.com/mitchellh/mapstructure"
+	"github.com/packwiz/packwiz/core"
+)
+
+type ghUpdateData struct {
+	ModID            string `mapstructure:"mod-id"` // The slug of the repo but named modId for consistency reasons
+	InstalledVersion string `mapstructure:"version"`
+}
+
+type ghUpdater struct{}
+
+func (u ghUpdater) ParseUpdate(updateUnparsed map[string]interface{}) (interface{}, error) {
+	var updateData ghUpdateData
+	err := mapstructure.Decode(updateUnparsed, &updateData)
+	return updateData, err
+}
+
+type cachedStateStore struct {
+	ModID   string
+	Version ModReleases
+}
+
+func (u ghUpdater) CheckUpdate(mods []core.Mod, mcVersion string, pack core.Pack) ([]core.UpdateCheck, error) {
+	results := make([]core.UpdateCheck, len(mods))
+
+	for i, mod := range mods {
+		rawData, ok := mod.GetParsedUpdateData("modrinth")
+		if !ok {
+			results[i] = core.UpdateCheck{Error: errors.New("couldn't parse mod data")}
+			continue
+		}
+
+		data := rawData.(ghUpdateData)
+
+		newVersion, err := getLatestVersion(data.ModID, pack)
+		if err != nil {
+			results[i] = core.UpdateCheck{Error: fmt.Errorf("failed to get latest version: %v", err)}
+			continue
+		}
+
+		// if newVersion.ID == "" { //There is no version available for this minecraft version or loader.
+		// 	results[i] = core.UpdateCheck{UpdateAvailable: false}
+		// 	continue
+		// }
+
+		if newVersion.TagName == data.InstalledVersion { //The latest version from the site is the same as the installed one
+			results[i] = core.UpdateCheck{UpdateAvailable: false}
+			continue
+		}
+
+		if len(newVersion.Assets) == 0 {
+			results[i] = core.UpdateCheck{Error: errors.New("new version doesn't have any files")}
+			continue
+		}
+
+		newFilename := newVersion.Assets[0].Name
+
+		results[i] = core.UpdateCheck{
+			UpdateAvailable: true,
+			UpdateString:    mod.FileName + " -> " + newFilename,
+			CachedState:     cachedStateStore{data.ModID, newVersion},
+		}
+	}
+
+	return results, nil
+}
+
+func (u ghUpdater) DoUpdate(mods []*core.Mod, cachedState []interface{}) error {
+	for i, mod := range mods {
+		modState := cachedState[i].(cachedStateStore)
+		var version = modState.Version
+
+		var file = version.Assets[0]
+		for _, v := range version.Assets {
+			if strings.HasSuffix(v.Name, ".jar") {
+				file = v
+			}
+		}
+
+		hash, error := file.getSha256()
+		if error != nil || hash == "" {
+			return errors.New("file doesn't have a hash")
+		}
+
+		mod.FileName = file.Name
+		mod.Download = core.ModDownload{
+			URL:        file.BrowserDownloadURL,
+			HashFormat: "sha256",
+			Hash:       hash,
+		}
+		mod.Update["modrinth"]["version"] = version.ID
+	}
+
+	return nil
+}