package services

import "testing"

// Regression tests for directory-boundary folder matching.
//
// getRelativePath (and the folder-membership checks across the scanner)
// once used bare string-prefix matching, so a registered folder whose path
// was a string prefix of a sibling's ("/app/audiobooks" vs
// "/app/audiobookssd") claimed the sibling's files: relative paths were
// cut mid-component into "sd/..."-style garbage, stored that way, and
// resolved against the wrong root — covers 404ing while the bytes sat one
// directory away. folderContains pins the rule: a folder only ever claims
// itself or paths beneath it at a real separator boundary, regardless of
// names, registration order, or trailing slashes.

func TestFolderContains(t *testing.T) {
	tests := []struct {
		name   string
		folder string
		path   string
		want   bool
	}{
		{"exact root", "/app/books", "/app/books", true},
		{"direct child", "/app/books", "/app/books/x.epub", true},
		{"deep child", "/app/books", "/app/books/a/b/c.epub", true},
		{"sibling extension", "/app/books", "/app/books2", false},
		{"sibling extension child", "/app/books", "/app/books2/x.epub", false},
		{"mid-word sibling", "/data/lib", "/data/library/x.epub", false},
		{"suffix without separator", "/app/books", "/app/books-backup/x.epub", false},
		{"unrelated", "/app/books", "/opt/other/x.epub", false},
		{"prefix inside path segment", "/app/books", "/app/series/books/x.epub", false},
		{"trailing slash in folder", "/app/books/", "/app/books/x.epub", true},
		{"trailing slash exact", "/app/books/", "/app/books", true},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			if got := folderContains(tt.folder, tt.path); got != tt.want {
				t.Errorf("folderContains(%q, %q) = %v, want %v", tt.folder, tt.path, got, tt.want)
			}
		})
	}
}

func TestGetRelativePathFolderBoundary(t *testing.T) {
	// The prod trap: /app/audiobooks registered before /app/audiobookssd.
	// String-prefix cutting produced "sd/Brian Jacques/..." for every file
	// in the second folder; the boundary rule must make that impossible.
	newScanner := func(folders []string) *MediaScanner {
		s := NewMediaScanner(nil)
		s.folders = folders // SetFolders requires a live DB; tests only need path relativization
		return s
	}

	siblingFolders := []string{"/app/audiobooks", "/app/audiobookssd"}

	tests := []struct {
		name    string
		folders []string
		path    string
		want    string
	}{
		{
			name:    "sibling-prefix folder keeps its full name in relative path",
			folders: siblingFolders,
			path:    "/app/audiobookssd/Brian Jacques/Redwall/Book 01 - Redwall/file.m4b",
			want:    "Brian Jacques/Redwall/Book 01 - Redwall/file.m4b",
		},
		{
			name:    "first registered folder unaffected",
			folders: siblingFolders,
			path:    "/app/audiobooks/Author/Series/file.mp3",
			want:    "Author/Series/file.mp3",
		},
		{
			name:    "exact root yields empty path",
			folders: siblingFolders,
			path:    "/app/audiobookssd",
			want:    "",
		},
		{
			name:    "order independence: sibling registered first",
			folders: []string{"/app/audiobookssd", "/app/audiobooks"},
			path:    "/app/audiobookssd/Brian Jacques/Redwall/Book 01 - Redwall/file.m4b",
			want:    "Brian Jacques/Redwall/Book 01 - Redwall/file.m4b",
		},
		{
			name:    "order independence: first folder still correct when second registered first",
			folders: []string{"/app/audiobookssd", "/app/audiobooks"},
			path:    "/app/audiobooks/Author/Series/file.mp3",
			want:    "Author/Series/file.mp3",
		},
		{
			name:    "trailing slash on registered folders",
			folders: []string{"/app/audiobooks/", "/app/audiobookssd/"},
			path:    "/app/audiobookssd/Brian Jacques/file.m4b",
			want:    "Brian Jacques/file.m4b",
		},
		{
			name:    "mid-word sibling folders",
			folders: []string{"/data/lib", "/data/library"},
			path:    "/data/library/author/book.epub",
			want:    "author/book.epub",
		},
		{
			name:    "author/series/title layout preserved under true root",
			folders: siblingFolders,
			path:    "/app/audiobookssd/Brian Jacques/Redwall/Book 14 - The Taggerung/Taggerung.mp3",
			want:    "Brian Jacques/Redwall/Book 14 - The Taggerung/Taggerung.mp3",
		},
		{
			name:    "path outside every folder returned as-is",
			folders: siblingFolders,
			path:    "/app/audiobooksBackup/x.mp3",
			want:    "/app/audiobooksBackup/x.mp3",
		},
		{
			name:    "unrelated path returned as-is",
			folders: siblingFolders,
			path:    "/elsewhere/x.mp3",
			want:    "/elsewhere/x.mp3",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			s := newScanner(tt.folders)
			if got := s.getRelativePath(tt.path); got != tt.want {
				t.Errorf("getRelativePath(%q) with folders %v = %q, want %q", tt.path, tt.folders, got, tt.want)
			}
		})
	}
}