feat: configurable OPDS download folder and filename format (#2571)

test/opds_filename/OpdsFilenameTest.cpp

@@ -0,0 +1,52 @@
+#include <gtest/gtest.h>
+
+#include <string>
+
+#include "OpdsFilename.h"
+
+namespace {
+
+TEST(OpdsFilename, AuthorTitleIsDefaultOrder) {
+  EXPECT_EQ(opdsBookFilename("J. Doe", "My Book", OpdsFilenameFormat::AuthorTitle), "J. Doe - My Book.epub");
+}
+
+TEST(OpdsFilename, TitleAuthorSwapsOrder) {
+  EXPECT_EQ(opdsBookFilename("J. Doe", "My Book", OpdsFilenameFormat::TitleAuthor), "My Book - J. Doe.epub");
+}
+
+TEST(OpdsFilename, TitleOnlyIgnoresAuthor) {
+  EXPECT_EQ(opdsBookFilename("J. Doe", "My Book", OpdsFilenameFormat::TitleOnly), "My Book.epub");
+}
+
+TEST(OpdsFilename, EmptyAuthorCollapsesToTitleForEveryFormat) {
+  EXPECT_EQ(opdsBookFilename("", "My Book", OpdsFilenameFormat::AuthorTitle), "My Book.epub");
+  EXPECT_EQ(opdsBookFilename("", "My Book", OpdsFilenameFormat::TitleAuthor), "My Book.epub");
+  EXPECT_EQ(opdsBookFilename("", "My Book", OpdsFilenameFormat::TitleOnly), "My Book.epub");
+}
+
+TEST(OpdsFilename, IllegalCharactersAreSanitized) {
+  // '/' ':' '*' '?' etc. are replaced with '_' by sanitizeFilename.
+  EXPECT_EQ(opdsBookFilename("A/B", "C:D*E?", OpdsFilenameFormat::AuthorTitle), "A_B - C_D_E_.epub");
+}
+
+TEST(OpdsFilename, EmptyAuthorAndTitleFallsBackToBook) {
+  // sanitizeFilename returns "book" when nothing usable remains.
+  EXPECT_EQ(opdsBookFilename("", "", OpdsFilenameFormat::AuthorTitle), "book.epub");
+  EXPECT_EQ(opdsBookFilename("", "", OpdsFilenameFormat::TitleOnly), "book.epub");
+}
+
+TEST(OpdsFilename, LongNameIsTruncatedToByteBudgetBeforeExtension) {
+  // sanitizeFilename caps the base at 100 bytes; ".epub" is appended after.
+  const std::string longTitle(200, 'a');
+  const std::string result = opdsBookFilename("", longTitle, OpdsFilenameFormat::TitleOnly);
+  EXPECT_EQ(result, std::string(100, 'a') + ".epub");
+  EXPECT_EQ(result.size(), 105u);
+}
+
+TEST(OpdsFilename, UnknownFormatValueFallsBackToAuthorTitle) {
+  // Defensive: a persisted value outside the enum still yields a valid name.
+  const auto bogus = static_cast<OpdsFilenameFormat>(99);
+  EXPECT_EQ(opdsBookFilename("J. Doe", "My Book", bogus), "J. Doe - My Book.epub");
+}
+
+}  // namespace