Added playlist import (and sync)from m3u files, ref #391

src/libs/metadata/impl/Parser.cpp

@@ -269,6 +269,32 @@ namespace lms::metadata
         }
     }
 
+    std::span<const std::filesystem::path> Parser::getSupportedExtensions() const
+    {
+        // TODO: use backend capability to retrieve supported formats
+        static const std::array<std::filesystem::path, 18> fileExtensions{
+            ".aac",
+            ".alac",
+            ".aif",
+            ".aiff",
+            ".ape",
+            ".dsf",
+            ".flac",
+            ".m4a",
+            ".m4b",
+            ".mp3",
+            ".mpc",
+            ".oga",
+            ".ogg",
+            ".opus",
+            ".shn",
+            ".wav",
+            ".wma",
+            ".wv",
+        };
+        return fileExtensions;
+    }
+
     std::unique_ptr<Track> Parser::parse(const std::filesystem::path& p, bool debug)
     {
         try

src/libs/metadata/impl/Parser.hpp

@@ -34,6 +34,7 @@ namespace lms::metadata
         std::unique_ptr<Track> parse(const ITagReader& reader);
 
     private:
+        std::span<const std::filesystem::path> getSupportedExtensions() const override;
         void setUserExtraTags(std::span<const std::string> extraTags) override { _userExtraTags.assign(std::cbegin(extraTags), std::cend(extraTags)); }
         void setArtistTagDelimiters(std::span<const std::string> delimiters) override { _artistTagDelimiters.assign(std::cbegin(delimiters), std::cend(delimiters)); }
         void setDefaultTagDelimiters(std::span<const std::string> delimiters) override { _defaultTagDelimiters.assign(std::cbegin(delimiters), std::cend(delimiters)); }

src/libs/metadata/impl/PlayList.cpp

@@ -0,0 +1,95 @@
+/*
+ * Copyright (C) 2024 Emeric Poupon
+ *
+ * This file is part of LMS.
+ *
+ * LMS is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * LMS is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with LMS.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "metadata/PlayList.hpp"
+
+#include <array>
+#include <string_view>
+
+#include "core/String.hpp"
+
+namespace lms::metadata
+{
+    std::span<const std::filesystem::path> getSupportedPlayListFileExtensions()
+    {
+        static const std::array<std::filesystem::path, 2> fileExtensions{ ".m3u", "m3u8" };
+        return fileExtensions;
+    }
+
+    namespace
+    {
+        struct Comment
+        {
+            std::string_view directive;
+            std::string_view parameter;
+        };
+
+        std::optional<Comment> parseComment(std::string_view line)
+        {
+            if (line.empty() || line.front() != '#')
+                return std::nullopt;
+
+            Comment comment;
+            const std::string_view::size_type parameterSeparator{ line.find(':') };
+            if (parameterSeparator == std::string_view::npos)
+            {
+                comment.directive = line;
+            }
+            else
+            {
+                comment.directive = line.substr(0, parameterSeparator + 1);
+                comment.parameter = line.substr(parameterSeparator + 1);
+            };
+
+            return comment;
+        }
+    } // namespace
+
+    PlayList parsePlayList(std::istream& is)
+    {
+        PlayList playlist;
+
+        std::string line;
+        while (std::getline(is, line))
+        {
+            const std::string_view trimmedLine{ core::stringUtils::stringTrim(line) };
+            if (trimmedLine.empty())
+                continue;
+
+            // Don't enforce #EXTM3U as first line: be permissive
+            if (const std::optional<Comment> comment{ parseComment(trimmedLine) })
+            {
+                if (comment->directive == "#PLAYLIST:")
+                    playlist.name = comment->parameter;
+
+                continue;
+            }
+
+            // filter out URI = scheme ":" ["//" authority] path ["?" query] ["#" fragment]
+            // Consider an entry with a ':' is actually an url, as filenames are not supposed to have ':' on windows
+            if (trimmedLine.find(':') != std::string_view::npos)
+                continue;
+
+            const std::filesystem::path path{ std::cbegin(trimmedLine), std::cend(trimmedLine) };
+            playlist.files.emplace_back(path.lexically_normal());
+        }
+
+        return playlist;
+    }
+} // namespace lms::metadata