package goffmpeg

/*
#cgo LDFLAGS: -ldl
#include <stdlib.h>
#include "libcffmpeg.h"
*/
import "C"
import (
	"errors"
	"fmt"
	"unsafe"
)

const (
	// ScaleNone self add no scale raw frame data
	ScaleNone = 0
	// ScaleFastBilinear SWS_FAST_BILINEAR
	ScaleFastBilinear = 1
	// ScaleBilinear SWS_BILINEAR
	ScaleBilinear = 2
	// ScaleBicubic SWS_BICUBIC
	ScaleBicubic = 4
	// ScaleX SWS_X
	ScaleX = 8
	// ScalePoint SWS_POINT
	ScalePoint = 0x10
	// ScaleArea SWS_AREA
	ScaleArea = 0x20
	// ScaleBicublin SWS_BICUBLIN
	ScaleBicublin = 0x40
	// ScaleGauss SWS_GAUSS
	ScaleGauss = 0x80
	// ScaleSinc SWS_SINC
	ScaleSinc = 0x100
	// ScaleLancZos SWS_LANCZOS
	ScaleLancZos = 0x200
	// ScaleSpline SWS_SPLINE
	ScaleSpline = 0x400
)

// SrcFormat format NV
const SrcFormat = 23

// DstFormat format
const DstFormat = 3

var libcffmpeg C.libcffmpeg

// InitFFmpeg init ffmepg
func InitFFmpeg(soFileGo string) error {
	soFile := C.CString(soFileGo)
	defer C.free(unsafe.Pointer(soFile))
	lib := C.init_libcffmpeg(soFile)
	if lib == nil {
		fmt.Println("open error: ", soFileGo)
		return errors.New("init ffmpeg error")
	}
	libcffmpeg = lib
	return nil
}

// FreeFFmpeg free ffmpeg
func FreeFFmpeg() {
	if libcffmpeg != nil {
		C.release_libcffmpeg(libcffmpeg)
	}
}

// GoFFMPEG handle for c
type GoFFMPEG struct {
	ffmpeg C.cffmpeg
}

// New 2nd new
func New(GB, CPU bool) *GoFFMPEG {

	f := C.wrap_fn_create(unsafe.Pointer(libcffmpeg))

	if f == nil {
		return nil
	}
	if GB {
		C.wrap_fn_run_gb28181(unsafe.Pointer(libcffmpeg), f)
	}
	if CPU {
		C.wrap_fn_use_cpu(unsafe.Pointer(libcffmpeg), f)
	}

	return &GoFFMPEG{
		ffmpeg: f,
	}
}

// NewWithLog log
func NewWithLog(GB, CPU bool, ffmpegLog string) *GoFFMPEG {
	lf := C.CString(ffmpegLog)
	defer C.free(unsafe.Pointer(lf))

	f := C.wrap_fn_create2(unsafe.Pointer(libcffmpeg), lf)
	if f == nil {
		return nil
	}
	if GB {
		C.wrap_fn_run_gb28181(unsafe.Pointer(libcffmpeg), f)
	}
	if CPU {
		C.wrap_fn_use_cpu(unsafe.Pointer(libcffmpeg), f)
	}

	return &GoFFMPEG{
		ffmpeg: f,
	}
}

// Free free handle
func (h *GoFFMPEG) Free() {
	if h.ffmpeg != nil {
		C.wrap_fn_destroy(unsafe.Pointer(libcffmpeg), h.ffmpeg)
	}
}

// Run ffmpeg
func (h *GoFFMPEG) Run(input string) {
	in := C.CString(input)
	defer C.free(unsafe.Pointer(in))

	C.wrap_fn_run(unsafe.Pointer(libcffmpeg), h.ffmpeg, in)
}

// FPS fps
func (h *GoFFMPEG) FPS() int {
	return int(C.wrap_fn_fps(unsafe.Pointer(libcffmpeg), h.ffmpeg))
}

// ReleaseC release c memory
func ReleaseC(p unsafe.Pointer) {
	if p == nil {
		return
	}
	C.free(unsafe.Pointer(p))
}