align with metadata standard

internal/storage/field_index_test.go

@@ -59,7 +59,7 @@ func TestFieldIndex_SetMetadataFlatIndexesFields(t *testing.T) {
 			"filePath":                      "/files/watch/a.mkv",
 			"sizeByte":                      "123",
 			"cids/bafkreiaaa":               "true",
-			"titles/jpn":                    "ナルト",
+			"titles/jpn/ナルト":                "true",
 			"categories/TV/UHD":             "true",
 			"info/files/0/path":             "a.mkv",
 			"provenance":                    `{"source":"gateway"}`,
@@ -380,7 +380,7 @@ func TestFieldIndex_WarmBuildsEveryMissingIndex(t *testing.T) {
 		// written through the normal path (already indexed).
 		legacy := map[string]map[string]string{
 			"old1": {"filePath": "/a.mkv", "cids/bafkreiaaa": "true"},
-			"old2": {"filePath": "/b.mkv", "titles/jpn": "ナルト", "deep/a/b": "x"},
+			"old2": {"filePath": "/b.mkv", "titles/jpn/ナルト": "true", "deep/a/b": "x"},
 		}
 		for root, fields := range legacy {
 			for f, v := range fields {
@@ -407,7 +407,7 @@ func TestFieldIndex_WarmBuildsEveryMissingIndex(t *testing.T) {
 		if got := fieldNames(t, c, "old1"); !reflect.DeepEqual(got, []string{"cids/bafkreiaaa", "filePath"}) {
 			t.Errorf("old1 index = %v", got)
 		}
-		if got := fieldNames(t, c, "old2"); !reflect.DeepEqual(got, []string{"deep/a/b", "filePath", "titles/jpn"}) {
+		if got := fieldNames(t, c, "old2"); !reflect.DeepEqual(got, []string{"deep/a/b", "filePath", "titles/jpn/ナルト"}) {
 			t.Errorf("old2 index = %v", got)
 		}
 		if got := fieldNames(t, c, "fresh"); !reflect.DeepEqual(got, []string{"title"}) {
@@ -425,7 +425,7 @@ func TestFieldIndex_WarmBuildsEveryMissingIndex(t *testing.T) {
 		if _, err := c.WarmFieldIndexes(); err != nil {
 			t.Fatalf("second WarmFieldIndexes: %v", err)
 		}
-		if got := fieldNames(t, c, "old2"); !reflect.DeepEqual(got, []string{"deep/a/b", "filePath", "titles/jpn"}) {
+		if got := fieldNames(t, c, "old2"); !reflect.DeepEqual(got, []string{"deep/a/b", "filePath", "titles/jpn/ナルト"}) {
 			t.Errorf("old2 index after second warm = %v", got)
 		}
 	})

internal/storage/search_dirty.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"log"
+	"sort"
 	"strings"
 	"time"
 )
@@ -202,6 +203,11 @@ func (c *Client) GetSearchIndexTuplesFor(hashIDs []string) (tuples []SearchTuple
 // blob. Shared by the full and incremental index reads so the two can never
 // disagree about what is searchable — a drift there would make a record's
 // matchability depend on which path happened to index it.
+//
+// Beyond the flat fields it folds in every `titles/<lang3>/<name>` member's
+// name (METADATA_KEYS.md §3): the name lives in the key and the value is the
+// sentinel "true", so a search for an alternative title (`3 percent`) finds the
+// record whose `title` is `3%`.
 func buildHaystack(fields map[string]string) string {
 	var sb strings.Builder
 	for _, f := range searchIndexFields {
@@ -210,5 +216,30 @@ func buildHaystack(fields map[string]string) string {
 			sb.WriteByte('\n')
 		}
 	}
+	for _, name := range titleMemberNames(fields) {
+		sb.WriteString(strings.ToLower(name))
+		sb.WriteByte('\n')
+	}
 	return sb.String()
 }
+
+// titleMemberNames returns the names of a record's `titles/<lang3>/<name>`
+// key-set members, with the `∕` (U+2215) a writer substitutes for `/` mapped
+// back. Sorted: the fields map has no order, and the full and incremental
+// builds must produce byte-identical haystacks.
+func titleMemberNames(fields map[string]string) []string {
+	var names []string
+	for k, v := range fields {
+		rest, ok := strings.CutPrefix(k, "titles/")
+		if !ok || v == "" || v == "false" {
+			continue
+		}
+		_, name, ok := strings.Cut(rest, "/")
+		if !ok || name == "" {
+			continue
+		}
+		names = append(names, strings.ReplaceAll(name, "\u2215", "/"))
+	}
+	sort.Strings(names)
+	return names
+}

internal/storage/search_dirty_test.go

@@ -174,6 +174,8 @@ func TestDirty_IncrementalTuplesMatchTheFullRebuild(t *testing.T) {
 			"title":                   "Parity Release",
 			"fileName":                "parity.s01e01.mkv",
 			"fileType":                "video",
+			"titles/eng/3 Percent":    "true",
+			"titles/fra/3 Pourcent":   "true",
 			"categories/XXX":          "true",
 			"categories/newznab/5070": "true",
 		}); err != nil {
@@ -209,3 +211,20 @@ func TestDirty_IncrementalTuplesMatchTheFullRebuild(t *testing.T) {
 		}
 	})
 }
+
+// A `titles/<lang3>/<name>` member contributes its NAME (the key), never its
+// "true" value, and the `∕` a writer substituted for `/` reads back as `/`.
+func TestBuildHaystack_FoldsTitleMemberNames(t *testing.T) {
+	got := buildHaystack(map[string]string{
+		"title":                     "3%",
+		"titles/fra/3 Pourcent":     "true",
+		"titles/eng/3 Percent":      "true",
+		"titles/und/Fate\u2215Zero": "true",
+		"titles/eng":                "Retired Scalar",
+		"titles/eng/":               "true",
+	})
+	want := "3%\n3 percent\n3 pourcent\nfate/zero\n"
+	if got != want {
+		t.Errorf("haystack = %q, want %q", got, want)
+	}
+}