1 files changed, 79 insertions, 0 deletions
diff --git a/worker/jmap/cache/cache.go b/worker/jmap/cache/cache.go
new file mode 100644
index 00000000..ab264744
--- /dev/null
+++ b/worker/jmap/cache/cache.go
@@ -0,0 +1,79 @@
+package cache
+
+import (
+	"errors"
+	"os"
+	"path"
+
+	"github.com/mitchellh/go-homedir"
+	"github.com/syndtr/goleveldb/leveldb"
+)
+
+type JMAPCache struct {
+	mem      map[string][]byte
+	file     *leveldb.DB
+	blobsDir string
+}
+
+func NewJMAPCache(state, blobs bool, accountName string) (*JMAPCache, error) {
+	c := new(JMAPCache)
+	cacheDir, err := os.UserCacheDir()
+	if err != nil {
+		cacheDir, err = homedir.Expand("~/.cache")
+		if err != nil {
+			return nil, err
+		}
+	}
+	if state {
+		dir := path.Join(cacheDir, "aerc", accountName, "state")
+		_ = os.MkdirAll(dir, 0o700)
+		c.file, err = leveldb.OpenFile(dir, nil)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		c.mem = make(map[string][]byte)
+	}
+	if blobs {
+		c.blobsDir = path.Join(cacheDir, "aerc", accountName, "blobs")
+	}
+	return c, nil
+}
+
+var notfound = errors.New("key not found")
+
+func (c *JMAPCache) get(key string) ([]byte, error) {
+	switch {
+	case c.file != nil:
+		return c.file.Get([]byte(key), nil)
+	case c.mem != nil:
+		value, ok := c.mem[key]
+		if !ok {
+			return nil, notfound
+		}
+		return value, nil
+	}
+	panic("jmap cache with no backend")
+}
+
+func (c *JMAPCache) put(key string, value []byte) error {
+	switch {
+	case c.file != nil:
+		return c.file.Put([]byte(key), value, nil)
+	case c.mem != nil:
+		c.mem[key] = value
+		return nil
+	}
+	panic("jmap cache with no backend")
+}
+
+func (c *JMAPCache) delete(key string) error {
+	switch {
+	case c.file != nil:
+		return c.file.Delete([]byte(key), nil)
+	case c.mem != nil:
+		delete(c.mem, key)
+		return nil
+	}
+	panic("jmap cache with no backend")
+}