1 files changed, 121 insertions, 0 deletions
diff --git a/internal/hexaicli/cache.go b/internal/hexaicli/cache.go
new file mode 100644
index 0000000..544eab0
--- /dev/null
+++ b/internal/hexaicli/cache.go
@@ -0,0 +1,121 @@
+package hexaicli
+
+import (
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
+	"os"
+	"path/filepath"
+	"time"
+
+	"codeberg.org/snonux/hexai/internal/llm"
+	"codeberg.org/snonux/hexai/internal/stats"
+)
+
+const cliResponseCacheTTL = 24 * time.Hour
+
+var nowCLIResponseCache = time.Now
+
+type cliResponseCacheKey struct {
+	Provider    string        `json:"provider"`
+	Model       string        `json:"model"`
+	Messages    []llm.Message `json:"messages"`
+	MaxTokens   int           `json:"max_tokens,omitempty"`
+	Temperature *float64      `json:"temperature,omitempty"`
+}
+
+type cliResponseCacheEntry struct {
+	CreatedAt time.Time `json:"created_at"`
+	Output    string    `json:"output"`
+}
+
+func newCLIResponseCacheKey(provider, model string, req requestArgs, msgs []llm.Message) cliResponseCacheKey {
+	return cliResponseCacheKey{
+		Provider:    provider,
+		Model:       model,
+		Messages:    cloneCLIMessages(msgs),
+		MaxTokens:   req.maxTokens,
+		Temperature: cloneCLITemperature(req.temperature),
+	}
+}
+
+func lookupCLIResponseCache(key cliResponseCacheKey) (string, time.Duration, bool) {
+	path, ok := cliResponseCachePath(key)
+	if !ok {
+		return "", 0, false
+	}
+	entry, ok := loadCLIResponseCacheEntry(path)
+	if !ok {
+		return "", 0, false
+	}
+	age := nowCLIResponseCache().Sub(entry.CreatedAt)
+	if age > cliResponseCacheTTL {
+		_ = os.Remove(path)
+		return "", 0, false
+	}
+	return entry.Output, age, true
+}
+
+func storeCLIResponseCache(key cliResponseCacheKey, output string) {
+	path, ok := cliResponseCachePath(key)
+	if !ok {
+		return
+	}
+	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
+		return
+	}
+	entry := cliResponseCacheEntry{CreatedAt: nowCLIResponseCache().UTC(), Output: output}
+	data, err := json.Marshal(entry)
+	if err != nil {
+		return
+	}
+	_ = os.WriteFile(path, data, 0o600)
+}
+
+func cliResponseCachePath(key cliResponseCacheKey) (string, bool) {
+	dir, err := stats.CacheDir()
+	if err != nil {
+		return "", false
+	}
+	fingerprint, ok := cliResponseCacheFingerprint(key)
+	if !ok {
+		return "", false
+	}
+	return filepath.Join(dir, "cli-responses", fingerprint+".json"), true
+}
+
+func cliResponseCacheFingerprint(key cliResponseCacheKey) (string, bool) {
+	data, err := json.Marshal(key)
+	if err != nil {
+		return "", false
+	}
+	sum := sha256.Sum256(data)
+	return hex.EncodeToString(sum[:]), true
+}
+
+func loadCLIResponseCacheEntry(path string) (cliResponseCacheEntry, bool) {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return cliResponseCacheEntry{}, false
+	}
+	var entry cliResponseCacheEntry
+	if err := json.Unmarshal(data, &entry); err != nil {
+		_ = os.Remove(path)
+		return cliResponseCacheEntry{}, false
+	}
+	return entry, true
+}
+
+func cloneCLIMessages(msgs []llm.Message) []llm.Message {
+	out := make([]llm.Message, len(msgs))
+	copy(out, msgs)
+	return out
+}
+
+func cloneCLITemperature(temp *float64) *float64 {
+	if temp == nil {
+		return nil
+	}
+	value := *temp
+	return &value
+}