Feat (RAG): tying tui calls to rag funcs [WIP; skip-ci]

RAG itself is annoying to properly implement, plucking sentences with no
context is useless. Also it should not be a part of main package, same
for goes for tui. The number of global vars is absurd.

storage/migrations/002_add_vector.up.sql

@@ -4,3 +4,10 @@ CREATE VIRTUAL TABLE IF NOT EXISTS embeddings USING vec0(
     slug TEXT NOT NULL,
     raw_text TEXT NOT NULL
 );
+
+CREATE VIRTUAL TABLE IF NOT EXISTS embeddings_384 USING vec0(
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    embedding FLOAT[384],
+    slug TEXT NOT NULL,
+    raw_text TEXT NOT NULL
+);

storage/vector.go

@@ -2,6 +2,7 @@ package storage
 
 import (
 	"elefant/models"
+	"errors"
 	"fmt"
 	"log"
 	"unsafe"
@@ -11,29 +12,61 @@ import (
 
 type VectorRepo interface {
 	WriteVector(*models.VectorRow) error
-	SearchClosest(q [5120]float32) (*models.VectorRow, error)
+	SearchClosest(q []float32) (*models.VectorRow, error)
 }
 
-var vecTableName = "embeddings"
+var (
+	vecTableName    = "embeddings"
+	vecTableName384 = "embeddings_384"
+)
+
+func fetchTableName(emb []float32) (string, error) {
+	switch len(emb) {
+	case 5120:
+		return vecTableName, nil
+	case 384:
+		return vecTableName384, nil
+	default:
+		return "", fmt.Errorf("no table for the size of %d", len(emb))
+	}
+}
 
 func (p ProviderSQL) WriteVector(row *models.VectorRow) error {
+	tableName, err := fetchTableName(row.Embeddings)
+	if err != nil {
+		return err
+	}
 	stmt, _, err := p.s3Conn.Prepare(
-		fmt.Sprintf("INSERT INTO %s(embedding, slug, raw_text) VALUES (?, ?, ?)", vecTableName))
-	defer stmt.Close()
+		fmt.Sprintf("INSERT INTO %s(embedding, slug, raw_text) VALUES (?, ?, ?)", tableName))
 	if err != nil {
 		p.logger.Error("failed to prep a stmt", "error", err)
 		return err
 	}
+	defer stmt.Close()
 	v, err := sqlite_vec.SerializeFloat32(row.Embeddings)
 	if err != nil {
 		p.logger.Error("failed to serialize vector",
 			"emb-len", len(row.Embeddings), "error", err)
 		return err
 	}
-	stmt.BindInt(1, int(row.ID))
-	stmt.BindBlob(2, v)
-	stmt.BindText(3, row.Slug)
-	stmt.BindText(4, row.RawText)
+	if v == nil {
+		err = errors.New("empty vector after serialization")
+		p.logger.Error("empty vector after serialization",
+			"emb-len", len(row.Embeddings), "text", row.RawText, "error", err)
+		return err
+	}
+	if err := stmt.BindBlob(1, v); err != nil {
+		p.logger.Error("failed to bind", "error", err)
+		return err
+	}
+	if err := stmt.BindText(2, row.Slug); err != nil {
+		p.logger.Error("failed to bind", "error", err)
+		return err
+	}
+	if err := stmt.BindText(3, row.RawText); err != nil {
+		p.logger.Error("failed to bind", "error", err)
+		return err
+	}
 	err = stmt.Exec()
 	if err != nil {
 		p.logger.Error("failed exec a stmt", "error", err)
@@ -46,19 +79,19 @@ func decodeUnsafe(bs []byte) []float32 {
 	return unsafe.Slice((*float32)(unsafe.Pointer(&bs[0])), len(bs)/4)
 }
 
-func (p ProviderSQL) SearchClosest(q [5120]float32) (*models.VectorRow, error) {
-	stmt, _, err := p.s3Conn.Prepare(`
-		SELECT
+func (p ProviderSQL) SearchClosest(q []float32) (*models.VectorRow, error) {
+	stmt, _, err := p.s3Conn.Prepare(
+		fmt.Sprintf(`SELECT
 			id,
 			distance,
 			embedding,
 			slug,
 			raw_text
-		FROM vec_items
+		FROM %s
 		WHERE embedding MATCH ?
 		ORDER BY distance
 		LIMIT 4
-	`)
+	`, vecTableName))
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -66,7 +99,10 @@ func (p ProviderSQL) SearchClosest(q [5120]float32) (*models.VectorRow, error) {
 	if err != nil {
 		log.Fatal(err)
 	}
-	stmt.BindBlob(1, query)
+	if err := stmt.BindBlob(1, query); err != nil {
+		p.logger.Error("failed to bind", "error", err)
+		return nil, err
+	}
 	resp := make([]models.VectorRow, 4)
 	i := 0
 	for stmt.Step() {