#ifndef FFMPEG_AUDIO_H
#define FFMPEG_AUDIO_H

#include <stdint.h>

#ifdef _WIN32
#ifdef LIB_COMPILE
#define FFMPEG_EXTERN __declspec(dllexport)
#else
#define FFMPEG_EXTERN __declspec(dllimport)
#endif
#else
#define FFMPEG_EXTERN
#endif

#ifdef __cplusplus
extern "C" {
#endif

/*
 * Audio-only Acinerella API.
 *
 * The implementation may be C++, but this header is plain C-compatible.
 * All public structs below are opaque handles, except ac_audio_info.
 */

typedef struct __fmpg_instance__ fmpg_instance;
typedef struct __fmpg_decoder__ fmpg_decoder;
typedef struct __fmpg_package__ fmpg_package;
typedef struct __fmpg_file_info__ fmpg_file_info;

typedef struct __fmpg_audio_info__ {
    int sample_rate;
    int channels;
    int bits_per_sample;     /* Always 32. */
    int bytes_per_sample;    /* Always 4. */
} fmpg_audio_info;

/* Lifecycle */
FFMPEG_EXTERN fmpg_instance *  ac_init(void);
FFMPEG_EXTERN void ac_free(fmpg_instance * instance);

FFMPEG_EXTERN int  ac_open_file(fmpg_instance * instance, const char *filename);
FFMPEG_EXTERN void ac_close(fmpg_instance * instance);
FFMPEG_EXTERN int  ac_is_open(fmpg_instance * instance);

/* Audio stream discovery */
FFMPEG_EXTERN int  ac_get_audio_stream_count(fmpg_instance * instance);
FFMPEG_EXTERN int  ac_get_default_audio_stream(fmpg_instance * instance);
FFMPEG_EXTERN int  ac_get_audio_info(fmpg_instance * instance, int stream_index, fmpg_audio_info *info);

/* Metadata. The returned strings are owned by the instance. */
FFMPEG_EXTERN const fmpg_file_info * ac_get_file_info(fmpg_instance * instance);

FFMPEG_EXTERN const char * ac_file_info_title(const fmpg_file_info *info);
FFMPEG_EXTERN const char * ac_file_info_author(const fmpg_file_info *info);
FFMPEG_EXTERN const char * ac_file_info_album(const fmpg_file_info *info);
FFMPEG_EXTERN const char * ac_file_info_genre(const fmpg_file_info *info);
FFMPEG_EXTERN const char * ac_file_info_comment(const fmpg_file_info *info);
FFMPEG_EXTERN const char * ac_file_info_copyright(const fmpg_file_info *info);

FFMPEG_EXTERN int  ac_file_info_year(const fmpg_file_info *info);
FFMPEG_EXTERN int  ac_file_info_track(const fmpg_file_info *info);
FFMPEG_EXTERN int64_t  ac_file_info_duration(const fmpg_file_info *info);
FFMPEG_EXTERN int  ac_file_info_bitrate(const fmpg_file_info *info);

/* Packet reading */
FFMPEG_EXTERN fmpg_package *  ac_read_package(fmpg_instance * instance);
FFMPEG_EXTERN void  ac_free_package(fmpg_package * package);
FFMPEG_EXTERN int  ac_package_stream_index(fmpg_package * package);

/* Decoder */
FFMPEG_EXTERN fmpg_decoder * ac_create_decoder(fmpg_instance * instance, int stream_index);

FFMPEG_EXTERN void  ac_free_decoder(fmpg_decoder * decoder);

/*
 * Decode one compressed packet.
 *
 * Returns 1 if PCM data was produced, 0 otherwise.
 *
 * Output format:
 *   signed 32-bit integer PCM
 *   interleaved
 *   native endian
 *
 * Example stereo layout:
 *   L0 R0 L1 R1 L2 R2 ...
 */
FFMPEG_EXTERN int  ac_decode_package(fmpg_package * package, fmpg_decoder * decoder);

/*
 * Flush delayed decoder/resampler samples after EOF.
 *
 * Call this repeatedly after ac_read_package() returns NULL,
 * until it returns 0.
 */
FFMPEG_EXTERN int  ac_flush_decoder(fmpg_decoder * decoder);

/* Seek to absolute position in milliseconds. */
FFMPEG_EXTERN int  ac_seek_ms(fmpg_decoder * decoder, int64_t target_pos_ms);

/* Decoder output */
FFMPEG_EXTERN const uint8_t * ac_decoder_buffer(fmpg_decoder * decoder);
FFMPEG_EXTERN int  ac_decoder_buffer_size(fmpg_decoder * decoder);
FFMPEG_EXTERN double  ac_decoder_timecode(fmpg_decoder * decoder);
FFMPEG_EXTERN int  ac_decoder_stream_index(fmpg_decoder * decoder);

#ifdef __cplusplus
}
#endif

#endif