feat(ingestion): add wiki inventory loader

ingestion/internal/wiki/inventory.go

@@ -0,0 +1,68 @@
+// ingestion/internal/wiki/inventory.go
+package wiki
+
+import (
+	"bufio"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// LoadInventory walks brain/wiki/ and returns all pages grouped by type.
+// Missing subdirectories are silently skipped.
+func LoadInventory(brainDir string) (map[PageType][]Entry, error) {
+	result := map[PageType][]Entry{
+		PageTypeConcept: {},
+		PageTypeEntity:  {},
+		PageTypeSource:  {},
+	}
+	for pt := range result {
+		dir := filepath.Join(brainDir, "wiki", string(pt))
+		entries, err := os.ReadDir(dir)
+		if os.IsNotExist(err) {
+			continue
+		}
+		if err != nil {
+			return nil, err
+		}
+		for _, e := range entries {
+			if e.IsDir() || !strings.HasSuffix(e.Name(), ".md") {
+				continue
+			}
+			slug := strings.TrimSuffix(e.Name(), ".md")
+			path := filepath.Join(dir, e.Name())
+			title := readTitle(path, slug)
+			result[pt] = append(result[pt], Entry{Slug: slug, Title: title, Type: pt})
+		}
+	}
+	return result, nil
+}
+
+// readTitle extracts the title from YAML frontmatter, falling back to slug.
+func readTitle(path, fallback string) string {
+	f, err := os.Open(path)
+	if err != nil {
+		return fallback
+	}
+	defer f.Close()
+
+	scanner := bufio.NewScanner(f)
+	inFM := false
+	for scanner.Scan() {
+		line := scanner.Text()
+		if strings.TrimSpace(line) == "---" {
+			if !inFM {
+				inFM = true
+				continue
+			}
+			break
+		}
+		if inFM {
+			key, val, ok := strings.Cut(line, ":")
+			if ok && strings.TrimSpace(key) == "title" {
+				return strings.Trim(strings.TrimSpace(val), `"'`)
+			}
+		}
+	}
+	return fallback
+}

ingestion/internal/wiki/inventory_test.go

@@ -0,0 +1,62 @@
+// ingestion/internal/wiki/inventory_test.go
+package wiki
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestLoadInventory(t *testing.T) {
+	dir := t.TempDir()
+	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki", "concepts"), 0o755))
+	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki", "entities"), 0o755))
+	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki", "sources"), 0o755))
+
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "wiki", "concepts", "domain-driven-design.md"),
+		[]byte("---\ntitle: Domain Driven Design\n---\n\n## Definition\n\nA thing.\n"),
+		0o644,
+	))
+	require.NoError(t, os.WriteFile(
+		filepath.Join(dir, "wiki", "entities", "ryan-singer.md"),
+		[]byte("---\ntitle: Ryan Singer\n---\n\n## Description\n\nDesigner.\n"),
+		0o644,
+	))
+
+	inv, err := LoadInventory(dir)
+	require.NoError(t, err)
+
+	assert.Len(t, inv[PageTypeConcept], 1)
+	assert.Equal(t, "domain-driven-design", inv[PageTypeConcept][0].Slug)
+	assert.Equal(t, "Domain Driven Design", inv[PageTypeConcept][0].Title)
+
+	assert.Len(t, inv[PageTypeEntity], 1)
+	assert.Equal(t, "ryan-singer", inv[PageTypeEntity][0].Slug)
+
+	assert.Empty(t, inv[PageTypeSource])
+}
+
+func TestLoadInventory_EmptyDirs(t *testing.T) {
+	dir := t.TempDir()
+	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki", "concepts"), 0o755))
+	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki", "entities"), 0o755))
+	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki", "sources"), 0o755))
+
+	inv, err := LoadInventory(dir)
+	require.NoError(t, err)
+	assert.Empty(t, inv[PageTypeConcept])
+	assert.Empty(t, inv[PageTypeEntity])
+	assert.Empty(t, inv[PageTypeSource])
+}
+
+func TestLoadInventory_MissingDirsOk(t *testing.T) {
+	dir := t.TempDir()
+	// No wiki/ subdirs at all
+	inv, err := LoadInventory(dir)
+	require.NoError(t, err)
+	assert.NotNil(t, inv)
+}