feat(gemini-web): Add conversation affinity selector

internal/provider/gemini-web/conversation/alias.go

@@ -0,0 +1,80 @@
+package conversation
+
+import (
+	"strings"
+	"sync"
+
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/registry"
+)
+
+var (
+	aliasOnce sync.Once
+	aliasMap  map[string]string
+)
+
+// EnsureGeminiWebAliasMap populates the alias map once.
+func EnsureGeminiWebAliasMap() {
+	aliasOnce.Do(func() {
+		aliasMap = make(map[string]string)
+		for _, m := range registry.GetGeminiModels() {
+			if m.ID == "gemini-2.5-flash-lite" {
+				continue
+			}
+			if m.ID == "gemini-2.5-flash" {
+				aliasMap["gemini-2.5-flash-image-preview"] = "gemini-2.5-flash"
+			}
+			alias := AliasFromModelID(m.ID)
+			aliasMap[strings.ToLower(alias)] = strings.ToLower(m.ID)
+		}
+	})
+}
+
+// MapAliasToUnderlying normalizes a model alias to its underlying identifier.
+func MapAliasToUnderlying(name string) string {
+	EnsureGeminiWebAliasMap()
+	n := strings.ToLower(strings.TrimSpace(name))
+	if n == "" {
+		return n
+	}
+	if u, ok := aliasMap[n]; ok {
+		return u
+	}
+	const suffix = "-web"
+	if strings.HasSuffix(n, suffix) {
+		return strings.TrimSuffix(n, suffix)
+	}
+	return n
+}
+
+// AliasFromModelID mirrors the original helper for deriving alias IDs.
+func AliasFromModelID(modelID string) string {
+	return modelID + "-web"
+}
+
+// NormalizeModel returns the canonical identifier used for hashing.
+func NormalizeModel(model string) string {
+	return MapAliasToUnderlying(model)
+}
+
+// GetGeminiWebAliasedModels returns alias metadata for registry exposure.
+func GetGeminiWebAliasedModels() []*registry.ModelInfo {
+	EnsureGeminiWebAliasMap()
+	aliased := make([]*registry.ModelInfo, 0)
+	for _, m := range registry.GetGeminiModels() {
+		if m.ID == "gemini-2.5-flash-lite" {
+			continue
+		} else if m.ID == "gemini-2.5-flash" {
+			cpy := *m
+			cpy.ID = "gemini-2.5-flash-image-preview"
+			cpy.Name = "gemini-2.5-flash-image-preview"
+			cpy.DisplayName = "Nano Banana"
+			cpy.Description = "Gemini 2.5 Flash Preview Image"
+			aliased = append(aliased, &cpy)
+		}
+		cpy := *m
+		cpy.ID = AliasFromModelID(m.ID)
+		cpy.Name = cpy.ID
+		aliased = append(aliased, &cpy)
+	}
+	return aliased
+}

internal/provider/gemini-web/conversation/hash.go

@@ -0,0 +1,74 @@
+package conversation
+
+import (
+	"crypto/sha256"
+	"encoding/hex"
+	"fmt"
+	"strings"
+)
+
+// Message represents a minimal role-text pair used for hashing and comparison.
+type Message struct {
+	Role string `json:"role"`
+	Text string `json:"text"`
+}
+
+// StoredMessage mirrors the persisted conversation message structure.
+type StoredMessage struct {
+	Role    string `json:"role"`
+	Content string `json:"content"`
+	Name    string `json:"name,omitempty"`
+}
+
+// Sha256Hex computes SHA-256 hex digest for the specified string.
+func Sha256Hex(s string) string {
+	sum := sha256.Sum256([]byte(s))
+	return hex.EncodeToString(sum[:])
+}
+
+// ToStoredMessages converts in-memory messages into the persisted representation.
+func ToStoredMessages(msgs []Message) []StoredMessage {
+	out := make([]StoredMessage, 0, len(msgs))
+	for _, m := range msgs {
+		out = append(out, StoredMessage{Role: m.Role, Content: m.Text})
+	}
+	return out
+}
+
+// StoredToMessages converts stored messages back into the in-memory representation.
+func StoredToMessages(msgs []StoredMessage) []Message {
+	out := make([]Message, 0, len(msgs))
+	for _, m := range msgs {
+		out = append(out, Message{Role: m.Role, Text: m.Content})
+	}
+	return out
+}
+
+// hashMessage normalizes message data and returns a stable digest.
+func hashMessage(m StoredMessage) string {
+	s := fmt.Sprintf(`{"content":%q,"role":%q}`, m.Content, strings.ToLower(m.Role))
+	return Sha256Hex(s)
+}
+
+// HashConversationWithPrefix computes a conversation hash using the provided prefix (client identifier) and model.
+func HashConversationWithPrefix(prefix, model string, msgs []StoredMessage) string {
+	var b strings.Builder
+	b.WriteString(strings.ToLower(strings.TrimSpace(prefix)))
+	b.WriteString("|")
+	b.WriteString(strings.ToLower(strings.TrimSpace(model)))
+	for _, m := range msgs {
+		b.WriteString("|")
+		b.WriteString(hashMessage(m))
+	}
+	return Sha256Hex(b.String())
+}
+
+// HashConversationForAccount keeps compatibility with the per-account hash previously used.
+func HashConversationForAccount(clientID, model string, msgs []StoredMessage) string {
+	return HashConversationWithPrefix(clientID, model, msgs)
+}
+
+// HashConversationGlobal produces a hash suitable for cross-account lookups.
+func HashConversationGlobal(model string, msgs []StoredMessage) string {
+	return HashConversationWithPrefix("global", model, msgs)
+}

internal/provider/gemini-web/conversation/index.go

@@ -0,0 +1,187 @@
+package conversation
+
+import (
+	"encoding/json"
+	"errors"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+	"time"
+
+	bolt "go.etcd.io/bbolt"
+)
+
+const (
+	bucketMatches    = "matches"
+	defaultIndexFile = "gemini-web-index.bolt"
+)
+
+// MatchRecord stores persisted mapping metadata for a conversation prefix.
+type MatchRecord struct {
+	AccountLabel string   `json:"account_label"`
+	Metadata     []string `json:"metadata,omitempty"`
+	PrefixLen    int      `json:"prefix_len"`
+	UpdatedAt    int64    `json:"updated_at"`
+}
+
+// MatchResult combines a persisted record with the hash that produced it.
+type MatchResult struct {
+	Hash   string
+	Record MatchRecord
+	Model  string
+}
+
+var (
+	indexOnce sync.Once
+	indexDB   *bolt.DB
+	indexErr  error
+)
+
+func openIndex() (*bolt.DB, error) {
+	indexOnce.Do(func() {
+		path := indexPath()
+		if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
+			indexErr = err
+			return
+		}
+		db, err := bolt.Open(path, 0o600, &bolt.Options{Timeout: 2 * time.Second})
+		if err != nil {
+			indexErr = err
+			return
+		}
+		indexDB = db
+	})
+	return indexDB, indexErr
+}
+
+func indexPath() string {
+	wd, err := os.Getwd()
+	if err != nil || wd == "" {
+		wd = "."
+	}
+	return filepath.Join(wd, "conv", defaultIndexFile)
+}
+
+// StoreMatch persists or updates a conversation hash mapping.
+func StoreMatch(hash string, record MatchRecord) error {
+	if strings.TrimSpace(hash) == "" {
+		return errors.New("gemini-web conversation: empty hash")
+	}
+	db, err := openIndex()
+	if err != nil {
+		return err
+	}
+	record.UpdatedAt = time.Now().UTC().Unix()
+	payload, err := json.Marshal(record)
+	if err != nil {
+		return err
+	}
+	return db.Update(func(tx *bolt.Tx) error {
+		bucket, err := tx.CreateBucketIfNotExists([]byte(bucketMatches))
+		if err != nil {
+			return err
+		}
+		return bucket.Put([]byte(hash), payload)
+	})
+}
+
+// LookupMatch retrieves a stored mapping.
+func LookupMatch(hash string) (MatchRecord, bool, error) {
+	db, err := openIndex()
+	if err != nil {
+		return MatchRecord{}, false, err
+	}
+	var record MatchRecord
+	err = db.View(func(tx *bolt.Tx) error {
+		bucket := tx.Bucket([]byte(bucketMatches))
+		if bucket == nil {
+			return nil
+		}
+		raw := bucket.Get([]byte(hash))
+		if len(raw) == 0 {
+			return nil
+		}
+		return json.Unmarshal(raw, &record)
+	})
+	if err != nil {
+		return MatchRecord{}, false, err
+	}
+	if record.AccountLabel == "" || record.PrefixLen <= 0 {
+		return MatchRecord{}, false, nil
+	}
+	return record, true, nil
+}
+
+// RemoveMatch deletes a mapping for the given hash.
+func RemoveMatch(hash string) error {
+	db, err := openIndex()
+	if err != nil {
+		return err
+	}
+	return db.Update(func(tx *bolt.Tx) error {
+		bucket := tx.Bucket([]byte(bucketMatches))
+		if bucket == nil {
+			return nil
+		}
+		return bucket.Delete([]byte(hash))
+	})
+}
+
+// RemoveMatchesByLabel removes all entries associated with the specified label.
+func RemoveMatchesByLabel(label string) error {
+	label = strings.TrimSpace(label)
+	if label == "" {
+		return nil
+	}
+	db, err := openIndex()
+	if err != nil {
+		return err
+	}
+	return db.Update(func(tx *bolt.Tx) error {
+		bucket := tx.Bucket([]byte(bucketMatches))
+		if bucket == nil {
+			return nil
+		}
+		cursor := bucket.Cursor()
+		for k, v := cursor.First(); k != nil; k, v = cursor.Next() {
+			if len(v) == 0 {
+				continue
+			}
+			var record MatchRecord
+			if err := json.Unmarshal(v, &record); err != nil {
+				_ = bucket.Delete(k)
+				continue
+			}
+			if strings.EqualFold(strings.TrimSpace(record.AccountLabel), label) {
+				if err := bucket.Delete(k); err != nil {
+					return err
+				}
+			}
+		}
+		return nil
+	})
+}
+
+// StoreConversation updates all hashes representing the provided conversation snapshot.
+func StoreConversation(label, model string, msgs []Message, metadata []string) error {
+	label = strings.TrimSpace(label)
+	if label == "" || len(msgs) == 0 {
+		return nil
+	}
+	hashes := BuildStorageHashes(model, msgs)
+	if len(hashes) == 0 {
+		return nil
+	}
+	for _, h := range hashes {
+		rec := MatchRecord{
+			AccountLabel: label,
+			Metadata:     append([]string(nil), metadata...),
+			PrefixLen:    h.PrefixLen,
+		}
+		if err := StoreMatch(h.Hash, rec); err != nil {
+			return err
+		}
+	}
+	return nil
+}

internal/provider/gemini-web/conversation/lookup.go

@@ -0,0 +1,40 @@
+package conversation
+
+import "strings"
+
+// PrefixHash represents a hash candidate for a specific prefix length.
+type PrefixHash struct {
+	Hash      string
+	PrefixLen int
+}
+
+// BuildLookupHashes generates hash candidates ordered from longest to shortest prefix.
+func BuildLookupHashes(model string, msgs []Message) []PrefixHash {
+	if len(msgs) < 2 {
+		return nil
+	}
+	model = NormalizeModel(model)
+	sanitized := SanitizeAssistantMessages(msgs)
+	result := make([]PrefixHash, 0, len(sanitized))
+	for end := len(sanitized); end >= 2; end-- {
+		tailRole := strings.ToLower(strings.TrimSpace(sanitized[end-1].Role))
+		if tailRole != "assistant" && tailRole != "system" {
+			continue
+		}
+		prefix := sanitized[:end]
+		hash := HashConversationGlobal(model, ToStoredMessages(prefix))
+		result = append(result, PrefixHash{Hash: hash, PrefixLen: end})
+	}
+	return result
+}
+
+// BuildStorageHashes returns hashes representing the full conversation snapshot.
+func BuildStorageHashes(model string, msgs []Message) []PrefixHash {
+	if len(msgs) == 0 {
+		return nil
+	}
+	model = NormalizeModel(model)
+	sanitized := SanitizeAssistantMessages(msgs)
+	hash := HashConversationGlobal(model, ToStoredMessages(sanitized))
+	return []PrefixHash{{Hash: hash, PrefixLen: len(sanitized)}}
+}

internal/provider/gemini-web/conversation/metadata.go

@@ -0,0 +1,6 @@
+package conversation
+
+const (
+	MetadataMessagesKey = "gemini_web_messages"
+	MetadataMatchKey    = "gemini_web_match"
+)

internal/provider/gemini-web/conversation/parse.go

@@ -0,0 +1,102 @@
+package conversation
+
+import (
+	"strings"
+
+	"github.com/tidwall/gjson"
+)
+
+// ExtractMessages attempts to build a message list from the inbound request payload.
+func ExtractMessages(handlerType string, raw []byte) []Message {
+	if len(raw) == 0 {
+		return nil
+	}
+	if msgs := extractOpenAIStyle(raw); len(msgs) > 0 {
+		return msgs
+	}
+	if msgs := extractGeminiContents(raw); len(msgs) > 0 {
+		return msgs
+	}
+	return nil
+}
+
+func extractOpenAIStyle(raw []byte) []Message {
+	root := gjson.ParseBytes(raw)
+	messages := root.Get("messages")
+	if !messages.Exists() {
+		return nil
+	}
+	out := make([]Message, 0, 8)
+	messages.ForEach(func(_, entry gjson.Result) bool {
+		role := strings.ToLower(strings.TrimSpace(entry.Get("role").String()))
+		if role == "" {
+			return true
+		}
+		if role == "system" {
+			return true
+		}
+		var contentBuilder strings.Builder
+		content := entry.Get("content")
+		if !content.Exists() {
+			out = append(out, Message{Role: role, Text: ""})
+			return true
+		}
+		switch content.Type {
+		case gjson.String:
+			contentBuilder.WriteString(content.String())
+		case gjson.JSON:
+			if content.IsArray() {
+				content.ForEach(func(_, part gjson.Result) bool {
+					if text := part.Get("text"); text.Exists() {
+						if contentBuilder.Len() > 0 {
+							contentBuilder.WriteString("\n")
+						}
+						contentBuilder.WriteString(text.String())
+					}
+					return true
+				})
+			}
+		}
+		out = append(out, Message{Role: role, Text: contentBuilder.String()})
+		return true
+	})
+	if len(out) == 0 {
+		return nil
+	}
+	return out
+}
+
+func extractGeminiContents(raw []byte) []Message {
+	contents := gjson.GetBytes(raw, "contents")
+	if !contents.Exists() {
+		return nil
+	}
+	out := make([]Message, 0, 8)
+	contents.ForEach(func(_, entry gjson.Result) bool {
+		role := strings.TrimSpace(entry.Get("role").String())
+		if role == "" {
+			role = "user"
+		} else {
+			role = strings.ToLower(role)
+			if role == "model" {
+				role = "assistant"
+			}
+		}
+		var builder strings.Builder
+		entry.Get("parts").ForEach(func(_, part gjson.Result) bool {
+			if text := part.Get("text"); text.Exists() {
+				if builder.Len() > 0 {
+					builder.WriteString("\n")
+				}
+				builder.WriteString(text.String())
+			}
+			return true
+		})
+		out = append(out, Message{Role: role, Text: builder.String()})
+		return true
+	})
+	if len(out) == 0 {
+		return nil
+	}
+	return out
+}

internal/provider/gemini-web/conversation/sanitize.go

@@ -0,0 +1,39 @@
+package conversation
+
+import (
+	"regexp"
+	"strings"
+)
+
+var reThink = regexp.MustCompile(`(?is)<think>.*?</think>`)
+
+// RemoveThinkTags strips <think>...</think> blocks and trims whitespace.
+func RemoveThinkTags(s string) string {
+	return strings.TrimSpace(reThink.ReplaceAllString(s, ""))
+}
+
+// SanitizeAssistantMessages removes think tags from assistant messages while leaving others untouched.
+func SanitizeAssistantMessages(msgs []Message) []Message {
+	out := make([]Message, 0, len(msgs))
+	for _, m := range msgs {
+		if strings.EqualFold(strings.TrimSpace(m.Role), "assistant") {
+			out = append(out, Message{Role: m.Role, Text: RemoveThinkTags(m.Text)})
+			continue
+		}
+		out = append(out, m)
+	}
+	return out
+}
+
+// EqualMessages compares two message slices for equality.
+func EqualMessages(a, b []Message) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i := range a {
+		if a[i].Role != b[i].Role || a[i].Text != b[i].Text {
+			return false
+		}
+	}
+	return true
+}