chore: checkpoint stable battle and eidolon progression

internal/common/persistent_store.go

@@ -0,0 +1,198 @@
+package common
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"reflect"
+	"sync"
+)
+
+var persistentWriteMu sync.Mutex
+
+func ReadPersistent() (*Persistent, error) {
+	raw, err := os.ReadFile("persistent")
+	if err != nil {
+		return nil, err
+	}
+	var p Persistent
+	if err := json.Unmarshal(raw, &p); err != nil {
+		return nil, fmt.Errorf("parse persistent: %w", err)
+	}
+	return &p, nil
+}
+
+func jsonObject(value any) (map[string]any, error) {
+	raw, err := json.Marshal(value)
+	if err != nil {
+		return nil, err
+	}
+	var object map[string]any
+	err = json.Unmarshal(raw, &object)
+	return object, err
+}
+
+func (f *FreesrData) persistentSnapshot() Persistent {
+	ex := make(map[uint32]bool)
+	for id := range AvatarExRankMap {
+		if avatar := f.Avatars[id]; avatar != nil {
+			ex[id] = avatar.ExRankUnlocked
+		}
+	}
+	return Persistent{Lineups: f.Lineups, Position: f.Position, Scene: f.Scene,
+		MainCharacter: f.MainCharacter, MarchType: f.MarchType,
+		EnableSWGlobal: f.EnableSWGlobal, EnableCastoriceGlobal: f.EnableCastoriceGlobal,
+		EnableAhaGlobal: f.EnableAhaGlobal, DressedSkins: f.DressedSkins, ExRanksUnlocked: ex}
+}
+
+// Apply only locally changed fields. A stale game session saving its position
+// must not undo an EX switch written by the SDK process. Nested maps are merged
+// per key so different avatars' switches do not overwrite one another.
+func mergePersistentChanges(existing, baseline, next map[string]any) {
+	for key, value := range next {
+		old, known := baseline[key]
+		if known && reflect.DeepEqual(old, value) {
+			continue
+		}
+		newMap, newOK := value.(map[string]any)
+		oldMap, oldOK := old.(map[string]any)
+		if newOK && oldOK {
+			dest, ok := existing[key].(map[string]any)
+			if !ok {
+				dest = make(map[string]any)
+			}
+			mergePersistentChanges(dest, oldMap, newMap)
+			for removed := range oldMap {
+				if _, present := newMap[removed]; !present {
+					delete(dest, removed)
+				}
+			}
+			existing[key] = dest
+		} else {
+			existing[key] = value
+		}
+	}
+}
+
+func writeJSONAtomic(path string, value any) error {
+	raw, err := json.MarshalIndent(value, "", "  ")
+	if err != nil {
+		return err
+	}
+	file, err := os.CreateTemp(".", ".gac-save-*.tmp")
+	if err != nil {
+		return err
+	}
+	name := file.Name()
+	defer os.Remove(name)
+	if _, err := file.Write(raw); err != nil {
+		file.Close()
+		return err
+	}
+	if err := file.Close(); err != nil {
+		return err
+	}
+	return os.Rename(name, path)
+}
+
+func (f *FreesrData) SavePersistentChecked() error {
+	persistentWriteMu.Lock()
+	defer persistentWriteMu.Unlock()
+	unlock, err := lockPersistentFile()
+	if err != nil {
+		return err
+	}
+	defer unlock()
+	next, err := jsonObject(f.persistentSnapshot())
+	if err != nil {
+		return err
+	}
+	existing := make(map[string]any)
+	if raw, err := os.ReadFile("persistent"); err == nil {
+		if err := json.Unmarshal(raw, &existing); err != nil {
+			return fmt.Errorf("refuse to overwrite invalid persistent: %w", err)
+		}
+	} else if !os.IsNotExist(err) {
+		return err
+	}
+	mergePersistentChanges(existing, f.persistentBaseline, next)
+	if err := writeJSONAtomic("persistent", existing); err != nil {
+		return err
+	}
+	// Track our own observed snapshot, not external changes we have not loaded.
+	f.persistentBaseline = next
+	return nil
+}
+
+// RefreshExRanks imports persisted switches without replacing inventory,
+// lineup, scene or the configured battle. Call under the session state lock.
+func (f *FreesrData) RefreshExRanks(p *Persistent) []uint32 {
+	var changed []uint32
+	for id := range AvatarExRankMap {
+		avatar := f.Avatars[id]
+		if avatar == nil {
+			continue
+		}
+		unlocked := p.ExRanksUnlocked[id]
+		if avatar.ExRankUnlocked != unlocked {
+			avatar.ExRankUnlocked = unlocked
+			changed = append(changed, id)
+		}
+	}
+	if current, err := jsonObject(f.persistentSnapshot()); err == nil {
+		if f.persistentBaseline == nil {
+			f.persistentBaseline = make(map[string]any)
+		}
+		f.persistentBaseline["ex_ranks_unlocked"] = current["ex_ranks_unlocked"]
+	}
+	return changed
+}
+
+// Patch only the selected avatar's rank in the latest import. Unknown FreeSR
+// fields and all inventory IDs/affixes retain their original JSON values.
+func SaveAvatarRank(id, rank uint32) error {
+	persistentWriteMu.Lock()
+	defer persistentWriteMu.Unlock()
+	unlock, err := lockPersistentFile()
+	if err != nil {
+		return err
+	}
+	defer unlock()
+	raw, err := os.ReadFile("freesr-data.json")
+	if err != nil {
+		return err
+	}
+	var root map[string]json.RawMessage
+	if err := json.Unmarshal(raw, &root); err != nil {
+		return err
+	}
+	var avatars map[uint32]json.RawMessage
+	if err := json.Unmarshal(root["avatars"], &avatars); err != nil {
+		return err
+	}
+	var avatar map[string]json.RawMessage
+	if err := json.Unmarshal(avatars[id], &avatar); err != nil {
+		return err
+	}
+	var data map[string]json.RawMessage
+	if err := json.Unmarshal(avatar["data"], &data); err != nil {
+		return err
+	}
+	data["rank"], err = json.Marshal(rank)
+	if err != nil {
+		return err
+	}
+	avatar["data"], err = json.Marshal(data)
+	if err != nil {
+		return err
+	}
+	avatars[id], err = json.Marshal(avatar)
+	if err != nil {
+		return err
+	}
+	root["avatars"], err = json.Marshal(avatars)
+	if err != nil {
+		return err
+	}
+	return writeJSONAtomic("freesr-data.json", root)
+}