Add support for quotes in search strings

* Closes: #33

lib/database/books.go

@@ -171,15 +171,18 @@ type columnq struct {
 }
 
 func buildQuery(query string) (textQuery string, columnQuerys []columnq, trigramQuerys []columnq) {
-	words := strings.Split(query, " ")
-	for _, w := range words {
-		if w == "" {
+	tokens := extractTokens(query)
+	for _, token := range tokens {
+		if token == "" {
 			continue
 		}
-		tag := strings.SplitN(w, ":", 2)
-		if len(tag) > 1 && tag[1] != "" {
-			value := strings.Replace(tag[1], "%", "\\%", 0)
+		tag := strings.SplitN(token, ":", 2)
+		value := ""
+		if len(tag) > 1 {
+			value = strings.Replace(tag[1], "%", "\\%", 0)
 			value = strings.Replace(value, "_", "\\_", 0)
+		}
+
 		switch tag[0] {
 		case "lang":
 			columnQuerys = append(columnQuerys, columnq{"lang", value})
@@ -198,22 +201,37 @@ func buildQuery(query string) (textQuery string, columnQuerys []columnq, trigram
 		case "tag":
 			trigramQuerys = append(trigramQuerys, columnq{"text(tags)", value})
 		default:
-				if len(textQuery) != 0 {
-					textQuery += " | "
-				}
-				textQuery += w
-			}
-		} else {
 			if len(textQuery) != 0 {
 				lastChar := textQuery[len(textQuery)-1:]
-				if w != "&" && w != "|" && lastChar != "&" && lastChar != "|" {
+				if token[:1] != "&" && token[:1] != "|" && lastChar != "&" && lastChar != "|" {
 					textQuery += " | "
 				} else {
 					textQuery += " "
 				}
 			}
-			textQuery += w
+			textQuery += strings.Join(strings.Fields(token), " <-> ")
 		}
 	}
 	return
 }
+
+func extractTokens(query string) []string {
+	tokens := []string{}
+	quoted := strings.Split(query, "\"")
+	for i, s := range quoted {
+		if i%2 == 0 {
+			tokens = append(tokens, strings.Fields(s)...)
+		} else {
+			// quoted string
+			if len(tokens) > 0 {
+				lastToken := tokens[len(tokens)-1]
+				if len(lastToken) > 0 && lastToken[len(lastToken)-1] == ':' {
+					tokens[len(tokens)-1] += s
+					continue
+				}
+			}
+			tokens = append(tokens, s)
+		}
+	}
+	return tokens
+}