loader logic revised

client/loader/state.go

@@ -0,0 +1,61 @@
+package loader
+
+import (
+	"errors"
+	"fmt"
+	mc "galaxy/model/client"
+)
+
+func (l *loader) loadCurrentState() (*mc.State, bool, error) {
+	stateExists, err := l.storage.StateExists()
+	if err != nil {
+		return nil, false, fmt.Errorf("State file lookup error: %w", err)
+	}
+	if !stateExists {
+		return nil, false, nil
+	}
+	if s, err := l.storage.LoadState(); err != nil {
+		return nil, false, fmt.Errorf("State read error: %w", err)
+	} else {
+		return &s, true, nil
+	}
+}
+
+func (l *loader) updateCurrentVersion(v string) error {
+	state, stateExists, err := l.loadCurrentState()
+	if err != nil {
+		return fmt.Errorf("Load State error: %w", err)
+	}
+	if !stateExists {
+		state = &mc.State{}
+	}
+	if state.ClientCurrentVersion == v {
+		return nil
+	}
+	state.ClientCurrentVersion = v
+	if err := l.storage.SaveState(*state); err != nil {
+		return fmt.Errorf("State write error: %w", err)
+	}
+	return nil
+}
+
+func (l *loader) setNextVersion(v *string) error {
+	state, stateExists, err := l.loadCurrentState()
+	if err != nil {
+		return fmt.Errorf("Load State error: %w", err)
+	}
+	if !stateExists {
+		return errors.New("State was never saved, unable to set next version")
+	}
+	if state.ClientNextVersion != nil && v != nil && *state.ClientNextVersion == *v {
+		return nil
+	}
+	if state.ClientNextVersion == v {
+		return nil
+	}
+	state.ClientNextVersion = v
+	if err := l.storage.SaveState(*state); err != nil {
+		return fmt.Errorf("State write error: %w", err)
+	}
+	return nil
+}