package astiav

//#include <libavfilter/avfilter.h>
import "C"
import (
	"unsafe"
)

// https://github.com/FFmpeg/FFmpeg/blob/n5.0/libavfilter/avfilter.h#L165
type Filter struct {
	c *C.AVFilter
}

func newFilterFromC(c *C.AVFilter) *Filter {
	if c == nil {
		return nil
	}
	return &Filter{c: c}
}

func FindFilterByName(n string) *Filter {
	cn := C.CString(n)
	defer C.free(unsafe.Pointer(cn))
	return newFilterFromC(C.avfilter_get_by_name(cn))
}

func (f *Filter) Name() string {
	return C.GoString(f.c.name)
}

func (f *Filter) String() string {
	return f.Name()
}

func (f *Filter) NbInputs() int {
	return int(f.c.nb_inputs)
}

func (f *Filter) NbOutputs() int {
	return int(f.c.nb_outputs)
}

func (f *Filter) Inputs() (ps []*FilterPad) {
	for idx := 0; idx < f.NbInputs(); idx++ {
		ps = append(ps, newFilterPad(MediaType(C.avfilter_pad_get_type(f.c.inputs, C.int(idx)))))
	}
	return
}

func (f *Filter) Outputs() (ps []*FilterPad) {
	for idx := 0; idx < f.NbOutputs(); idx++ {
		ps = append(ps, newFilterPad(MediaType(C.avfilter_pad_get_type(f.c.outputs, C.int(idx)))))
	}
	return
}