feat: v0 tab completion

.gitignore

@@ -50,3 +50,6 @@ overleaf.kubeconfig
 # coverage report
 coverage.out
 coverage.html
+
+# claude code
+CLAUDE.md

internal/api/chat/get_citation_keys.go

@@ -0,0 +1,43 @@
+package chat
+
+import (
+	"context"
+
+	"paperdebugger/internal/libs/contextutil"
+	"paperdebugger/internal/models"
+	chatv2 "paperdebugger/pkg/gen/api/chat/v2"
+)
+
+func (s *ChatServerV2) GetCitationKeys(
+	ctx context.Context,
+	req *chatv2.GetCitationKeysRequest,
+) (*chatv2.GetCitationKeysResponse, error) {
+	actor, err := contextutil.GetActor(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	settings, err := s.userService.GetUserSettings(ctx, actor.ID)
+	if err != nil {
+		return nil, err
+	}
+
+	llmProvider := &models.LLMProviderConfig{
+		APIKey: settings.OpenAIAPIKey,
+	}
+
+	citationKeys, err := s.aiClientV2.GetCitationKeys(
+		ctx,
+		req.GetSentence(),
+		actor.ID,
+		req.GetProjectId(),
+		llmProvider,
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	return &chatv2.GetCitationKeysResponse{
+		CitationKeys: citationKeys,
+	}, nil
+}

internal/services/toolkit/client/get_citation_keys.go

@@ -0,0 +1,119 @@
+package client
+
+// TODO: This file should not place in the client package.
+import (
+	"context"
+	"fmt"
+	"paperdebugger/internal/models"
+	"regexp"
+	"strings"
+
+	"github.com/openai/openai-go/v3"
+	"go.mongodb.org/mongo-driver/v2/bson"
+)
+
+// GetBibliography extracts bibliography content from a project's .bib files.
+// It excludes non-essential fields to save tokens when extracting relevant citation keys.
+func (a *AIClientV2) GetBibliographyForCitation(ctx context.Context, userId bson.ObjectID, projectId string) (string, error) {
+	project, err := a.projectService.GetProject(ctx, userId, projectId)
+	if err != nil {
+		return "", err
+	}
+
+	// Exclude fields that aren't useful for citation matching
+	var excludeRe, excludeBraceRe, excludeQuoteRe *regexp.Regexp
+
+	excludeFields := []string{
+		"address", "institution", "pages", "eprint", "primaryclass", "volume", "number", "edition", "numpages", "articleno",
+		"publisher", "editor", "doi", "url", "acmid", "issn", "archivePrefix", "year", "month", "day",
+		"eid", "lastaccessed", "organization", "school", "isbn", "mrclass", "mrnumber", "mrreviewer", "type", "order_no",
+		"location", "howpublished", "distincturl", "issue_date", "archived", "series", "source",
+	}
+
+	fieldsPattern := strings.Join(excludeFields, "|")
+	excludeRe = regexp.MustCompile(`(?i)^\s*(` + fieldsPattern + `)\s*=`)
+	excludeBraceRe = regexp.MustCompile(`(?i)^\s*(` + fieldsPattern + `)\s*=\s*\{`)
+	excludeQuoteRe = regexp.MustCompile(`(?i)^\s*(` + fieldsPattern + `)\s*=\s*"`)
+
+	var bibLines []string
+	for _, doc := range project.Docs {
+		if doc.Filepath == "" || !strings.HasSuffix(doc.Filepath, ".bib") {
+			continue
+		}
+		braceDepth := 0
+		inQuote := false
+		for _, line := range doc.Lines {
+			// Handle ongoing multi-line exclusion
+			if braceDepth > 0 {
+				braceDepth += strings.Count(line, "{") - strings.Count(line, "}")
+				continue
+			}
+			if inQuote {
+				if strings.Count(line, `"`)%2 == 1 {
+					inQuote = false
+				}
+				continue
+			}
+			// Skip comments
+			if strings.HasPrefix(strings.TrimSpace(line), "%") {
+				continue
+			}
+			// Skip empty lines
+			if strings.TrimSpace(line) == "" {
+				continue
+			}
+			// Skip excluded fields
+			if excludeRe != nil && excludeRe.MatchString(line) {
+				if excludeBraceRe.MatchString(line) {
+					braceDepth = strings.Count(line, "{") - strings.Count(line, "}")
+				} else if excludeQuoteRe.MatchString(line) && strings.Count(line, `"`)%2 == 1 {
+					inQuote = true
+				}
+				continue
+			}
+
+			bibLines = append(bibLines, line)
+		}
+	}
+
+	bibliography := strings.Join(bibLines, "\n")
+
+	// Normalize multiple spaces
+	multiSpaceRe := regexp.MustCompile(` {2,}`)
+	bibliography = multiSpaceRe.ReplaceAllString(bibliography, " ")
+
+	return bibliography, nil
+}
+
+func (a *AIClientV2) GetCitationKeys(ctx context.Context, sentence string, userId bson.ObjectID, projectId string, llmProvider *models.LLMProviderConfig) (string, error) {
+	bibliography, err := a.GetBibliographyForCitation(ctx, userId, projectId)
+
+	if err != nil {
+		return "", err
+	}
+
+	// Get citation keys from LLM
+	emptyCitation := "none"
+	message := fmt.Sprintf("Bibliography: %s\nSentence: %s\nBased on the sentence and bibliography, suggest only the most relevant citation keys separated by commas with no spaces (e.g. key1,key2). Be selective and only include citations that are directly relevant. Avoid suggesting more than 3 citations. If no relevant citations are found, return '%s'.", sentence, bibliography, emptyCitation)
+
+	_, resp, err := a.ChatCompletionV2(ctx, "gpt-5.2", OpenAIChatHistory{
+		openai.SystemMessage("You are a helpful assistant that suggests relevant citation keys."),
+		openai.UserMessage(message),
+	}, llmProvider)
+
+	if err != nil {
+		return "", err
+	}
+
+	if len(resp) == 0 {
+		return "", nil
+	}
+
+	citationKeys := strings.TrimSpace(resp[0].Payload.GetAssistant().GetContent())
+
+	if citationKeys == emptyCitation {
+		return "", nil
+	}
+
+	return citationKeys, nil
+}