package goffmpeg

/*
#include <stdlib.h>
#include "libcffmpeg.h"
*/
import "C"

import "unsafe"

/////////////// for decoder

// Decode decode jpeg file
// return val: -1 open error; -2, find stream error; -3, converter create error
func Decode(input string, gb bool) ([]byte, int, int) {
	in := C.CString(input)
	defer C.free(unsafe.Pointer(in))

	withGB := 0
	if gb {
		withGB = 1
	}

	var width C.int
	var height C.int
	p := C.wrap_fn_decode(unsafe.Pointer(libcffmpeg), in, C.int(withGB), &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, int(width), int(height)
}

// Decode2 decode jpeg file
// return val: -1 open error; -2, find stream error; -3, converter create error
func Decode2(input string, gb bool) (unsafe.Pointer, []byte, int, int) {
	in := C.CString(input)
	defer C.free(unsafe.Pointer(in))

	withGB := 0
	if gb {
		withGB = 1
	}

	var width C.int
	var height C.int
	p := C.wrap_fn_decode(unsafe.Pointer(libcffmpeg), in, C.int(withGB), &width, &height)

	if width > 0 && height > 0 {
		wid := int(width)
		hei := int(height)
		const maxLen = 0x7fffffff
		size := int(width * height * 3)
		data := (*[maxLen]byte)(unsafe.Pointer(p))[:size:size]

		return p, data, wid, hei
	}
	return nil, nil, 0, 0
}