package ffi

/*
#cgo CFLAGS: -I${SRCDIR}/../../target/bat-ffi
#cgo LDFLAGS: -L${SRCDIR}/../../target/debug -lbat_ffi
#include <stdlib.h>

typedef char* ccharp;
extern const char* bat_version();
extern void bat_free_string(char* s);
extern char* bat_manifest_inspect_json(const char* raw_json);
extern char* bat_sync_plan_json(const char* current_json, const char* previous_json);
*/
import "C"
import (
    "errors"
    "unsafe"
)

func Version() (string, error) {
    ptr := C.bat_version()
    if ptr == nil {
        return "", errors.New("bat_version returned nil")
    }
    defer C.bat_free_string((*C.char)(unsafe.Pointer(ptr)))
    return C.GoString(ptr), nil
}

func InspectManifest(rawJSON string) (string, error) {
    cRaw := C.CString(rawJSON)
    defer C.free(unsafe.Pointer(cRaw))

    ptr := C.bat_manifest_inspect_json(cRaw)
    if ptr == nil {
        return "", errors.New("bat_manifest_inspect_json returned nil")
    }
    defer C.bat_free_string((*C.char)(unsafe.Pointer(ptr)))
    return C.GoString(ptr), nil
}

func BuildSyncPlan(currentJSON, previousJSON string) (string, error) {
    cCurrent := C.CString(currentJSON)
    defer C.free(unsafe.Pointer(cCurrent))

    var cPrevious *C.char
    if previousJSON != "" {
        cPrevious = C.CString(previousJSON)
        defer C.free(unsafe.Pointer(cPrevious))
    }

    ptr := C.bat_sync_plan_json(cCurrent, cPrevious)
    if ptr == nil {
        return "", errors.New("bat_sync_plan_json returned nil")
    }
    defer C.bat_free_string((*C.char)(unsafe.Pointer(ptr)))
    return C.GoString(ptr), nil
}