From b259afa408e3adb209ec6b2115200e491f9dddce Mon Sep 17 00:00:00 2001
From: Veloman Yunkan <veloman.yunkan@gmail.com>
Date: Sat, 17 Apr 2021 00:32:04 +0400
Subject: [PATCH] Library::getBooksCategories()

Note: no unit test added
---
 include/library.h |  9 ++++++++-
 src/library.cpp   | 15 +++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/include/library.h b/include/library.h
index f358e6746..95d22e4bd 100644
--- a/include/library.h
+++ b/include/library.h
@@ -233,12 +233,19 @@ class Library
   unsigned int getBookCount(const bool localBooks, const bool remoteBooks) const;
 
   /**
-   * Get all langagues of the books in the library.
+   * Get all languagues of the books in the library.
    *
    * @return A list of languages.
    */
   std::vector<std::string> getBooksLanguages() const;
 
+  /**
+   * Get all categories of the books in the library.
+   *
+   * @return A list of categories.
+   */
+  std::vector<std::string> getBooksCategories() const;
+
   /**
    * Get all book creators of the books in the library.
    *
diff --git a/src/library.cpp b/src/library.cpp
index d8307c9ae..1147282df 100644
--- a/src/library.cpp
+++ b/src/library.cpp
@@ -201,6 +201,21 @@ std::vector<std::string> Library::getBooksLanguages() const
   return booksLanguages;
 }
 
+std::vector<std::string> Library::getBooksCategories() const
+{
+  std::set<std::string> categories;
+
+  for (const auto& pair: m_books) {
+    const auto& book = pair.second;
+    const auto& c = book.getCategory();
+    if ( !c.empty() ) {
+      categories.insert(c);
+    }
+  }
+
+  return std::vector<std::string>(categories.begin(), categories.end());
+}
+
 std::vector<std::string> Library::getBooksCreators() const
 {
   std::vector<std::string> booksCreators;