From e1a798828d0e9276adfdfd9dfd9f12998ccc48b8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20=C5=9Aled=C5=BA?= <michalsledz34@gmail.com>
Date: Sat, 20 Jan 2024 16:28:53 +0100
Subject: [PATCH] Move decoder initialization to decoder.c

---
 Makefile            |  7 +++++--
 c_src/xav/decoder.c | 37 +++++++++++++++++++++++++++++++++++++
 c_src/xav/decoder.h |  5 +++++
 c_src/xav/xav_nif.c | 27 ++-------------------------
 4 files changed, 49 insertions(+), 27 deletions(-)

diff --git a/Makefile b/Makefile
index cd93ed1..fdab0e2 100644
--- a/Makefile
+++ b/Makefile
@@ -13,6 +13,9 @@ FFMPEG_LIB_DIR = ffmpeg_build/lib
 # uncomment to compile with debug logs
 # XAV_DEBUG_LOGS = -DXAV_DEBUG=1
 
+HEADERS = $(XAV_DIR)/reader.h $(XAV_DIR)/decoder.h $(XAV_DIR)/utils.h
+SOURCES = $(XAV_DIR)/xav_nif.c $(XAV_DIR)/reader.c $(XAV_DIR)/decoder.c $(XAV_DIR)/utils.c
+
 ifeq ($(USE_BUNDLED_FFMPEG), true)
 CFLAGS = -fPIC -I$(ERTS_INCLUDE_DIR) -I${FFMPEG_INCLUDE_DIR} -I${XAV_DIR} -shared $(XAV_DEBUG_LOGS)
 LDFLAGS = -L$(FFMPEG_LIB_DIR) -Wl,--whole-archive -lavcodec -lswscale -lavutil -lavformat -Wl,--no-whole-archive 
@@ -21,9 +24,9 @@ CFLAGS = -fPIC -I$(ERTS_INCLUDE_DIR) -I${XAV_DIR} -shared $(XAV_DEBUG_LOGS)
 LDFLAGS = -lavcodec -lswscale -lavutil -lavformat -lavdevice -lswresample
 endif
 
-$(XAV_SO): Makefile $(XAV_DIR)/xav_nif.c $(XAV_DIR)/reader.h $(XAV_DIR)/reader.c $(XAV_DIR)/utils.h $(XAV_DIR)/utils.c
+$(XAV_SO): Makefile $(SOURCES) $(HEADERS)
 	mkdir -p $(PRIV_DIR)
-	$(CC) $(CFLAGS) $(XAV_DIR)/xav_nif.c $(XAV_DIR)/reader.c $(XAV_DIR)/utils.c -o $(XAV_SO) $(LDFLAGS)
+	$(CC) $(CFLAGS) $(SOURCES) -o $(XAV_SO) $(LDFLAGS)
 
 format:
 	clang-format -i $(XAV_DIR)/*
diff --git a/c_src/xav/decoder.c b/c_src/xav/decoder.c
index e69de29..c186811 100644
--- a/c_src/xav/decoder.c
+++ b/c_src/xav/decoder.c
@@ -0,0 +1,37 @@
+#include "decoder.h"
+
+int decoder_init(struct Decoder *decoder, const char *codec) {
+  decoder->swr_ctx = NULL;
+
+  if (strcmp(codec, "opus") == 0) {
+    decoder->media_type = AVMEDIA_TYPE_AUDIO;
+    decoder->codec = avcodec_find_decoder(AV_CODEC_ID_OPUS);
+    // we will initialize out_format_name with the first frame
+    decoder->out_format_name = NULL;
+  } else if (strcmp(codec, "vp8") == 0) {
+    decoder->media_type = AVMEDIA_TYPE_VIDEO;
+    decoder->codec = avcodec_find_decoder(AV_CODEC_ID_VP8);
+    decoder->out_format_name = "rgb";
+  } else {
+    return -1;
+  }
+
+  if (!decoder->codec) {
+    return -1;
+  }
+
+  decoder->c = avcodec_alloc_context3(decoder->codec);
+  if (!decoder->c) {
+    return -1;
+  }
+
+  if (avcodec_open2(decoder->c, decoder->codec, NULL) < 0) {
+    return -1;
+  }
+
+  return 0;
+}
+
+int decoder_decode(struct Decoder *decoder, AVPacket *pkt) {
+  return 0;
+}
\ No newline at end of file
diff --git a/c_src/xav/decoder.h b/c_src/xav/decoder.h
index 39c78a7..11856ee 100644
--- a/c_src/xav/decoder.h
+++ b/c_src/xav/decoder.h
@@ -1,4 +1,5 @@
 #include <libavcodec/avcodec.h>
+#include <libswresample/swresample.h>
 
 struct Decoder {
   enum AVMediaType media_type;
@@ -14,3 +15,7 @@ struct Decoder {
   uint8_t **frame_data;
   int *frame_linesize;
 };
+
+int decoder_init(struct Decoder *decoder, const char *codec);
+
+int decoder_decode(struct Decoder *decoder, AVPacket *pkt);
\ No newline at end of file
diff --git a/c_src/xav/xav_nif.c b/c_src/xav/xav_nif.c
index c71856c..49779df 100644
--- a/c_src/xav/xav_nif.c
+++ b/c_src/xav/xav_nif.c
@@ -119,7 +119,6 @@ ERL_NIF_TERM new_decoder(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
   }
 
   struct Decoder *decoder = enif_alloc_resource(decoder_resource_type, sizeof(struct Decoder));
-  decoder->swr_ctx = NULL;
 
   int codec_len;
   if (!enif_get_atom_length(env, argv[0], &codec_len, ERL_NIF_UTF8)) {
@@ -132,30 +131,8 @@ ERL_NIF_TERM new_decoder(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
     return xav_nif_raise(env, "failed_to_get_atom");
   }
 
-  if (strcmp(codec, "opus") == 0) {
-    decoder->media_type = AVMEDIA_TYPE_AUDIO;
-    decoder->codec = avcodec_find_decoder(AV_CODEC_ID_OPUS);
-    // we will initialize out_format_name with the first frame
-    decoder->out_format_name = NULL;
-  } else if (strcmp(codec, "vp8") == 0) {
-    decoder->media_type = AVMEDIA_TYPE_VIDEO;
-    decoder->codec = avcodec_find_decoder(AV_CODEC_ID_VP8);
-    decoder->out_format_name = "rgb";
-  } else {
-    return xav_nif_raise(env, "invalid_codec");
-  }
-
-  if (!decoder->codec) {
-    return xav_nif_raise(env, "decoder_not_found");
-  }
-
-  decoder->c = avcodec_alloc_context3(decoder->codec);
-  if (!decoder->c) {
-    return xav_nif_raise(env, "failed_to_alloc_context");
-  }
-
-  if (avcodec_open2(decoder->c, decoder->codec, NULL) < 0) {
-    return xav_nif_raise(env, "failed_to_open_codec");
+  if (decoder_init(decoder, codec) != 0) {
+    return xav_nif_raise(env, "failed_to_init_decoder");
   }
 
   ERL_NIF_TERM decoder_term = enif_make_resource(env, decoder);