Changed the playing code to use Playlists managed by a PlaylistManager. This allows you to have randomized playlists and stuff. Also, you can now access special functions via the contents of RFID tags. See the README for a list of available modes.

src/playlist_manager.cpp

@@ -0,0 +1,60 @@
+#include "playlist_manager.h"
+#include <SD.h>
+#include "spi_master.h"
+
+PlaylistManager::PlaylistManager() {
+	SPIMaster::select_sd();
+	File root = SD.open("/");
+	File entry;
+	while (entry = root.openNextFile()) {
+		String foldername = entry.name();
+		// Remove trailing slash
+		foldername.remove(foldername.length());
+		TRACE("Looking at %s...", foldername.c_str());
+		if (!entry.isDirectory() || foldername.startsWith("/.")) continue;
+		if (!SD.exists(foldername + "/ids.txt")) {
+			TRACE("No ids.txt -> ignoring\n");
+			continue;
+		}
+		File f = SD.open(foldername + "/ids.txt");
+		String buffer = "";
+		if (f.available()) {
+			do {
+				char c = f.read();
+				if (!f.available() && c!='\n' && c!='\r') {
+					buffer.concat(c);
+					c='\n';
+				}
+				
+				if (c=='\n' || c=='\r') {
+					if (buffer.length() > 0) {
+						_map[buffer] = foldername;
+						TRACE(" ID %s", buffer.c_str());
+						buffer="";
+					}
+				} else {
+					buffer.concat(c);
+				}
+			} while(f.available());
+		}
+		f.close();
+		entry.close();
+	}
+	root.close();
+	SPIMaster::select_sd(false);
+}
+
+Playlist* PlaylistManager::get_playlist_for_id(String id) {
+	if (!_map.count(id)) return NULL;
+	String folder = _map[id];
+	if (!_playlists.count(folder)) {
+		_playlists[folder] = new Playlist(folder);
+	}
+	return _playlists[folder];
+}
+
+void PlaylistManager::dump_ids() {
+	for (std::map<String, String>::iterator it = _map.begin(); it!=_map.end(); it++) {
+		INFO("  %s -> %s\n", it->first.c_str(), it->second.c_str());
+	}
+}