From 8c65cc185a892b342816b0b31ec5da1e991a8d44 Mon Sep 17 00:00:00 2001
From: Stephan Vedder <vedder@mbits.info>
Date: Mon, 20 Nov 2023 15:05:58 +0100
Subject: [PATCH] Meta: Add a minimal SDL2 based videoplayer for Lagom

---
 Meta/Lagom/CMakeLists.txt                     |   5 +
 .../Contrib/VideoPlayerSDL/CMakeLists.txt     |   7 ++
 Meta/Lagom/Contrib/VideoPlayerSDL/main.cpp    | 109 ++++++++++++++++++
 3 files changed, 121 insertions(+)
 create mode 100644 Meta/Lagom/Contrib/VideoPlayerSDL/CMakeLists.txt
 create mode 100644 Meta/Lagom/Contrib/VideoPlayerSDL/main.cpp

diff --git a/Meta/Lagom/CMakeLists.txt b/Meta/Lagom/CMakeLists.txt
index 5425d89dc5..ee13f7236a 100644
--- a/Meta/Lagom/CMakeLists.txt
+++ b/Meta/Lagom/CMakeLists.txt
@@ -549,6 +549,11 @@ if (BUILD_LAGOM)
             add_serenity_subdirectory(Meta/Lagom/Contrib/MacPDF)
         endif()
 
+        find_package(SDL2)
+        if(SDL2_FOUND)
+            add_serenity_subdirectory(Meta/Lagom/Contrib/VideoPlayerSDL)
+        endif()
+
         add_executable(icc ../../Userland/Utilities/icc.cpp)
         target_link_libraries(icc LibCore LibGfx LibMain)
 
diff --git a/Meta/Lagom/Contrib/VideoPlayerSDL/CMakeLists.txt b/Meta/Lagom/Contrib/VideoPlayerSDL/CMakeLists.txt
new file mode 100644
index 0000000000..540022a2b1
--- /dev/null
+++ b/Meta/Lagom/Contrib/VideoPlayerSDL/CMakeLists.txt
@@ -0,0 +1,7 @@
+add_compile_options(-DAK_DONT_REPLACE_STD)
+
+add_executable(VideoPlayerSDL
+    main.cpp
+)
+
+target_link_libraries(VideoPlayerSDL PRIVATE LibMain LibCore LibGfx LibVideo SDL2::SDL2)
diff --git a/Meta/Lagom/Contrib/VideoPlayerSDL/main.cpp b/Meta/Lagom/Contrib/VideoPlayerSDL/main.cpp
new file mode 100644
index 0000000000..9fff3b8a8b
--- /dev/null
+++ b/Meta/Lagom/Contrib/VideoPlayerSDL/main.cpp
@@ -0,0 +1,109 @@
+/*
+ * Copyright (c) 2023, Stephan Vedder <stephan.vedder@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibCore/ArgsParser.h>
+#include <LibCore/EventLoop.h>
+#include <LibCore/File.h>
+#include <LibCore/MappedFile.h>
+#include <LibMain/Main.h>
+#include <LibVideo/PlaybackManager.h>
+#include <SDL2/SDL.h>
+
+ErrorOr<int> serenity_main(Main::Arguments arguments)
+{
+    StringView filename = ""sv;
+    Core::ArgsParser args_parser;
+    args_parser.add_positional_argument(filename, "The video file to display.", "filename", Core::ArgsParser::Required::No);
+    args_parser.parse(arguments);
+
+    if (filename.is_empty()) {
+        warnln("No filename given");
+        return 1;
+    }
+
+    auto file = TRY(Core::File::open(filename, Core::File::OpenMode::Read));
+    auto mapped_file = TRY(Core::MappedFile::map_from_file(move(file), filename));
+    auto load_file_result = Video::PlaybackManager::from_mapped_file(move(mapped_file));
+    if (load_file_result.is_error()) {
+        warnln("Failed to decode file {}", filename);
+        return 1;
+    }
+
+    SDL_Texture* texture = NULL;
+    SDL_Renderer* renderer = NULL;
+    SDL_Window* window = NULL;
+
+    auto playback_manager = load_file_result.release_value();
+    playback_manager->on_video_frame = [&texture, &renderer, &window](RefPtr<Gfx::Bitmap> frame) {
+        // Delete texture if it doesn't match the frame size and resize window
+        if (texture != NULL) {
+            int width, height;
+            SDL_QueryTexture(texture, NULL, NULL, &width, &height);
+            if (width != frame->width() || height != frame->height()) {
+                SDL_DestroyTexture(texture);
+                texture = NULL;
+                SDL_SetWindowSize(window, frame->width(), frame->height());
+            }
+        }
+
+        // Create texture if it doesn't exist
+        if (texture == NULL) {
+            texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_XRGB8888, SDL_TEXTUREACCESS_STREAMING,
+                frame->width(),
+                frame->height());
+        }
+
+        u8* pixels = frame->scanline_u8(0);
+        int result = SDL_UpdateTexture(texture, NULL, pixels, frame->pitch());
+        if (result != 0) {
+            warnln("Failed to update texture: {} from pixels {}", SDL_GetError(), pixels);
+        }
+    };
+
+    playback_manager->on_decoder_error = [](auto error) {
+        warnln("Decoder error: {}", error.description());
+    };
+
+    playback_manager->on_fatal_playback_error = [](auto) {
+        warnln("Fatal decoder error");
+        exit(1);
+    };
+
+    SDL_Init(SDL_INIT_VIDEO);
+
+    auto& video_data = playback_manager->selected_video_track().video_data();
+    window = SDL_CreateWindow(
+        "VideoPlayer",
+        SDL_WINDOWPOS_UNDEFINED,
+        SDL_WINDOWPOS_UNDEFINED,
+        video_data.pixel_width,
+        video_data.pixel_height,
+        0);
+
+    renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
+    SDL_SetRenderDrawColor(renderer, 0, 0, 0, SDL_ALPHA_OPAQUE);
+
+    playback_manager->resume_playback();
+
+    Core::EventLoop event_loop;
+    while (playback_manager->is_playing()) {
+        SDL_Event event;
+        if (SDL_PollEvent(&event)) {
+            if (event.type == SDL_QUIT)
+                break;
+        }
+
+        event_loop.pump(Core::EventLoop::WaitMode::PollForEvents);
+
+        SDL_RenderClear(renderer);
+        SDL_RenderCopy(renderer, texture, NULL, NULL);
+        SDL_RenderPresent(renderer);
+    }
+
+    SDL_DestroyWindow(window);
+    SDL_Quit();
+    return 0;
+}