package goffmpeg

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

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

// New create handle
func New() *GoFFMPEG {
	soFile := C.CString("./runtime/libcffmpeg.so")
	defer C.free(unsafe.Pointer(soFile))
	lib := C.init_libcffmpeg(soFile)
	if lib == nil {
		fmt.Println("open libcffmpeg.so error")
		return nil
	}
	return &GoFFMPEG{
		lib:    lib,
		ffmpeg: C.wrap_fn_create(),
	}
}

// Free free handle
func (h *GoFFMPEG) Free() {
	C.wrap_fn_destroy(h.ffmpeg)
	C.release_libcffmpeg(h.lib)
}

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

	C.wrap_fn_run(h.ffmpeg, in)
}

// DecodeJPEG decode jpeg file
func (h *GoFFMPEG) DecodeJPEG(input string) ([]byte, int, int) {
	in := C.CString(input)
	defer C.free(unsafe.Pointer(in))

	var width C.int
	var height C.int
	p := C.wrap_fn_decode_jpeg(h.ffmpeg, in, &width, &height)
	defer C.free(p)

	if width > 0 && height > 0 {
		data := C.GoBytes(p, width*height*3)
		wid := int(width)
		hei := int(height)
		return data, wid, hei
	}
	return nil, 0, 0
}