Added tentacle updater.

internal/preferences/tentacles.go

@@ -212,6 +212,62 @@ func (page *tentaclePage) action(action int) (*tentacle.ManagementRequest, error
 		return nil, errors.New("Select a tentacle first.")
 	}
 	page.selectedKey = selected.key
+	if action == 21 {
+		if !selected.installed {
+			return nil, errors.New("Install this tentacle first.")
+		}
+		entry := selected.status.Entry
+		for _, update := range page.snapshot.Updates {
+			if update.ID != entry.ID {
+				continue
+			}
+			permissions := ""
+			foundManifest := false
+			for _, repository := range page.snapshot.Repositories {
+				if repository.URL != update.RepositoryURL || repository.ID != update.RepositoryID {
+					continue
+				}
+				for _, manifest := range repository.Tentacles {
+					if manifest.ID != update.LocalID {
+						continue
+					}
+					foundManifest = true
+					var previous []string
+					if entry.Presentation {
+						previous = append(previous, "presentation")
+					}
+					if entry.Interaction {
+						previous = append(previous, "interaction")
+					}
+					if entry.ReaderSettings {
+						previous = append(previous, "reader-settings")
+					}
+					if len(previous) == 0 {
+						previous = append(previous, "none")
+					}
+					declared := manifest.Capabilities
+					if len(declared) == 0 {
+						declared = []string{"none"}
+					}
+					permissions = "Current capabilities: " + strings.Join(previous, ", ") +
+						". Repository declares: " + strings.Join(declared, ", ") + "."
+				}
+			}
+			if !foundManifest {
+				return nil, errors.New("Updated package manifest is unavailable; refresh the repository before upgrading.")
+			}
+			message := fmt.Sprintf("Update %s from version %s to version %s?\n\n%s\n\nOnly update packages from publishers you trust. Tentacles run with your account's access.\n\nChanges take effect immediately.", update.Name, update.InstalledVersion, update.AvailableVersion, permissions)
+			text, button := C.CString(message), C.CString("Update")
+			accepted := C.prefs_tentacle_confirm(text, button)
+			C.free(unsafe.Pointer(text))
+			C.free(unsafe.Pointer(button))
+			if accepted == 0 {
+				return nil, nil
+			}
+			return &tentacle.ManagementRequest{Action: "upgrade", ID: update.LocalID, URL: update.RepositoryURL}, nil
+		}
+		return nil, errors.New("No newer version is available for the selected tentacle. Refresh its repository to check again.")
+	}
 	if !selected.installed {
 		if action != 11 && action != 19 {
 			return nil, errors.New("Install this tentacle first.")