#include <windows.h>
#include <vfw.h>
#include <stdio.h>

void sixty_fps(char *in, char *out);

int main(int argc, char **argv)
{
	if(argc < 3){
		fprintf(stderr, "ERROR: unsatisfactory argments\n");
		exit(EXIT_FAILURE);
	}
	
	AVIFileInit(); /* initialize VfW library */
	sixty_fps(argv[argc-2], argv[argc-1]);
	AVIFileExit(); /* release resources */

	return EXIT_SUCCESS;
}

void sixty_fps(char *in_path, char *out_path)
{
	PAVIFILE out_file;
	PAVISTREAM out_video;
	PAVIFILE in_file;
	PAVISTREAM in_video;

	AVISTREAMINFO info;

	LPVOID frame_format;
	LONG   frame_format_size;
	
	LPVOID frame;
	LONG   frame_size;

	int i,n, cinema;

	frame = NULL;

	if(AVIFileOpen(&in_file, in_path, OF_READ|OF_SHARE_EXCLUSIVE, NULL)){
		fprintf(stderr, "ERROR - %s open failed\n", in_path);
		goto SIXTY_FPS_1ST_LEVEL_ERROR;
	}

	if(AVIFileGetStream(in_file, &in_video, streamtypeVIDEO, 0)){
		fprintf(stderr, "ERROR - %s has no video stream", in_path);
		goto SIXTY_FPS_2ND_LEVEL_ERROR;
	}

	if(AVIStreamInfo(in_video, &info, sizeof(AVISTREAMINFO))){
		fprintf(stderr, "ERROR - failed to get %s stream info", in_path);
		goto SIXTY_FPS_3RD_LEVEL_ERROR;
	}
	
	switch( (info.dwRate+info.dwScale-1)/info.dwScale ){
	case 24:
		cinema = 1;
		info.dwRate *= 5;
		info.dwRate /= 2;
		break;
	case 30:
		cinema = 0;
		info.dwRate *= 2;
		break;
	default:
		fprintf(stderr, "ERROR - %s has unexpected fps, rate=%d, scale=%d\n", in_path, info.dwRate, info.dwScale);
		goto SIXTY_FPS_3RD_LEVEL_ERROR;
	}

	if(AVIStreamReadFormat(in_video, 0, NULL, &frame_format_size)){
		fprintf(stderr, "ERROR - failed to get %s frame format size", in_path);
		goto SIXTY_FPS_3RD_LEVEL_ERROR;
	}

	frame_format = malloc(frame_format_size);
	if(frame_format == NULL){
		fprintf(stderr, "ERROR - no enough memory space");
		goto SIXTY_FPS_3RD_LEVEL_ERROR;
	}

	if(AVIStreamReadFormat(in_video, 0, frame_format, &frame_format_size)){
		fprintf(stderr, "ERROR - failed to read %s video stream format", in_path);
		goto SIXTY_FPS_4TH_LEVEL_ERROR;
	}

	if(AVIFileOpen(&out_file, out_path, OF_CREATE|OF_WRITE, NULL)){
		fprintf(stderr, "ERROR - failed to create %s\n", out_path);
		goto SIXTY_FPS_4TH_LEVEL_ERROR;
	}
	
	if(AVIFileCreateStream(out_file, &out_video, &info)){
		fprintf(stderr, "ERROR - failed to create %s video stream", out_path);
		goto SIXTY_FPS_5TH_LEVEL_ERROR;
	}
	
	if(AVIStreamSetFormat(out_video, 0, frame_format, frame_format_size)){
		fprintf(stderr, "ERROR - failed to set %s video stream format", out_path);
		goto SIXTY_FPS_6TH_LEVEL_ERROR;
	}

	i = 0;
	n = 0;
	while(AVIStreamRead(in_video, n, 1, NULL, 0, &frame_size, NULL) == 0){
		frame = malloc(frame_size);
		if(frame == NULL){
			fprintf(stderr, "ERROR - no enough memory space");
			goto SIXTY_FPS_6TH_LEVEL_ERROR;
		}
		if(AVIStreamRead(in_video, n, 1, frame, frame_size, NULL, NULL)){
			fprintf(stderr, "ERROR - failed to read %s frame %d", in_file, n);
			goto SIXTY_FPS_7TH_LEVEL_ERROR;
		}
		if(AVIStreamIsKeyFrame(in_video, n)){
			if(AVIStreamWrite(out_video, i, 1, frame, frame_size, AVIIF_KEYFRAME, NULL, NULL)){
				fprintf(stderr, "ERROR - failed to write %s frame %d", out_file, i);
				goto SIXTY_FPS_7TH_LEVEL_ERROR;
			}
		}else{
			if(AVIStreamWrite(out_video, i, 1, frame, frame_size, 0, NULL, NULL)){
				fprintf(stderr, "ERROR - failed to write %s frame %d", out_file, i);
				goto SIXTY_FPS_7TH_LEVEL_ERROR;
			}
		}
		
		free(frame);
		frame = NULL;
		
		i += 1;
		if(cinema && (n&1)){
			if(AVIStreamWrite(out_video, i, 1, NULL, 0, 0, NULL, NULL)){
				fprintf(stderr, "ERROR - failed to write %s frame %d", out_file, i);
				goto SIXTY_FPS_6TH_LEVEL_ERROR;
			}
			i += 1;
		}
		if(AVIStreamWrite(out_video, i, 1, NULL, 0, 0, NULL, NULL)){
			fprintf(stderr, "ERROR - failed to write %s frame %d", out_file, i);
			goto SIXTY_FPS_6TH_LEVEL_ERROR;
		}
		i += 1;
		n += 1;
	}

SIXTY_FPS_7TH_LEVEL_ERROR:
	if(frame){
		free(frame);
	}
SIXTY_FPS_6TH_LEVEL_ERROR:
	AVIStreamRelease(out_video);
SIXTY_FPS_5TH_LEVEL_ERROR:
	AVIFileRelease(out_file);
SIXTY_FPS_4TH_LEVEL_ERROR:
	free(frame_format);
SIXTY_FPS_3RD_LEVEL_ERROR:
	AVIStreamRelease(in_video);
SIXTY_FPS_2ND_LEVEL_ERROR:
	AVIFileRelease(in_file);
SIXTY_FPS_1ST_LEVEL_ERROR:
	return;
}