feat: make everything threads-safe.

feat: complete `uninstall.sh` logic to make everything synced.
	feat: complete basic play logic to handle background, music,
	lyric play.

uninstall.cpp

@@ -1,7 +1,146 @@
-#include <iostream>
+// Hatsune Miku's Shoshitsu in Terminal
+//
+// The uninstall hook program: plays a short "show" in the terminal — an ASCII
+// video background at 60% brightness, a music track, and timed lyrics shown
+// above the video — all synchronised to one shared timeline.
+//
+// Compiles and runs on Windows (MSYS2/MinGW) as well as Linux.
 
-int main()
-{
-    
+#include "backgroundDisplay.h"
+#include "lyricResolve.h"
+#include "musicPlayer.h"
+#include "timeline.h"
+
+#include <atomic>
+#include <chrono>
+#include <cstdio>
+#include <string>
+#include <thread>
+
+// ---- global configuration --------------------------------------------------
+
+// Debug mode toggles how the show's resources are selected:
+//   true  -> behave like a normal binary; read --video / --audio / --lyrics
+//            from the command line (all three are required).
+//   false -> use the hardcoded default paths below (the uninstall-hook path,
+//            invoked by dpkg with no arguments).
+bool debugMode = true;
+
+const char* kDefaultVideoPath = "res/video.mp4";
+const char* kDefaultAudioPath = "res/music.flac";
+const char* kDefaultLyricPath = "res/lyric.lrc";
+
+// Shared playback clock. Every module receives a pointer to this so the video,
+// audio and lyrics stay in sync with each other.
+Timeline g_timeline;
+
+// ---- helpers ---------------------------------------------------------------
+
+static void printUsage(const char* argv0) {
+    std::printf(
+        "Usage: %s --video <file> --audio <file> --lyrics <file>\n"
+        "Play the show in the terminal: ASCII video at 60%% brightness,\n"
+        "music, and lyrics shown above the video on a shared timeline.\n"
+        "(debugMode = true; with debugMode = false the hardcoded defaults\n"
+        "in uninstall.cpp are used and no arguments are needed.)\n",
+        argv0);
+}
+
+static int runShow(const std::string& videoPath, const std::string& audioPath,
+                   const std::string& lyricPath) {
+    std::atomic<bool> stop{false};
+    g_timeline.start();
+
+    bd::GridSize videoGrid;
+    int videoOffsetX = 0;
+    std::atomic<bool> gridReady{false};
+
+    bd::PlayVideoOptions vo;
+    vo.loop = true;
+    vo.intensity = 0.6f;  // 60% brightness
+    vo.topRows = 1;       // one row above the video reserved for the lyrics
+    vo.outGrid = &videoGrid;
+    vo.outOffsetX = &videoOffsetX;
+    vo.gridReady = &gridReady;
+    vo.stop = &stop;
+
+    int videoResult = -1;
+    int musicResult = -1;
+    int lyricResult = -1;
+
+    std::thread videoThread([&] {
+        videoResult = bd::playVideo(videoPath, &g_timeline, vo);
+    });
+    std::thread musicThread([&] { musicResult = mp::play(audioPath, &g_timeline, &stop); });
+
+    // Wait for the video to report its grid, so the lyric line can be placed
+    // above the video and kept within the video's width.
+    for (int i = 0; i < 100 && !gridReady.load(); ++i) {
+        std::this_thread::sleep_for(std::chrono::milliseconds(10));
+    }
+
+    lr::LyricDisplayOptions lo;
+    lo.row = 1;                                        // the row above the video
+    lo.col = (videoGrid.cols > 0) ? videoOffsetX + 1 : 0;  // the video's left edge
+    lo.maxWidth = (videoGrid.cols > 0) ? videoGrid.cols : 0;  // within the video width
+    std::thread lyricThread([&] {
+        lyricResult = lr::playLyricsFile(lyricPath, lo, &g_timeline, &stop);
+    });
+
+    // The show ends when both the music and the lyrics have finished.
+    musicThread.join();
+    lyricThread.join();
+    stop.store(true);  // stop the looping video
+    videoThread.join();
+
+    // Restore a clean terminal.
+    std::printf("\x1b[0m\x1b[2J\x1b[H\x1b[?25h");
+
+    if (videoResult == 1) {
+        std::fprintf(stderr, "uninstall: could not open video '%s'\n", videoPath.c_str());
+    }
+    if (musicResult == 2) {
+        std::fprintf(stderr, "uninstall: could not open audio '%s'\n", audioPath.c_str());
+    } else if (musicResult == 3) {
+        std::fprintf(stderr, "uninstall: no audio device available (playing without sound)\n");
+    }
+    if (lyricResult != 0) {
+        std::fprintf(stderr, "uninstall: could not load lyrics '%s'\n", lyricPath.c_str());
+    }
     return 0;
 }
+
+int main(int argc, char** argv) {
+    std::string videoPath, audioPath, lyricPath;
+
+    if (debugMode) {
+        for (int i = 1; i < argc; ++i) {
+            const std::string a = argv[i];
+            if ((a == "--video" || a == "--audio" || a == "--lyrics") && i + 1 < argc) {
+                const std::string value = argv[++i];
+                if (a == "--video") videoPath = value;
+                else if (a == "--audio") audioPath = value;
+                else if (a == "--lyrics") lyricPath = value;
+            } else if (a == "-h" || a == "--help") {
+                printUsage(argv[0]);
+                return 0;
+            } else {
+                printUsage(argv[0]);
+                return 1;
+            }
+        }
+        if (videoPath.empty() || audioPath.empty() || lyricPath.empty()) {
+            std::fprintf(stderr,
+                         "error: --video, --audio and --lyrics are all required "
+                         "(or set debugMode = false to use the hardcoded defaults).\n");
+            printUsage(argv[0]);
+            return 1;
+        }
+    } else {
+        videoPath = kDefaultVideoPath;
+        audioPath = kDefaultAudioPath;
+        lyricPath = kDefaultLyricPath;
+    }
+
+    return runShow(videoPath, audioPath, lyricPath);
+}