#define PERL_NO_GET_CONTEXT
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
#include "duktape.h"
#include "duk_config.h"
#include "javascript_builtins.h"

MODULE = Peertube::DL::Javascript  PACKAGE = Peertube::DL::Javascript
PROTOTYPES: ENABLE

SV *
_duk_create_heap_default()
    CODE:
        duk_context *context = duk_create_heap_default();
        if (context) {
            duk_push_c_function(context, js_builtin_print, 1);
            duk_put_global_string(context, "print");
            RETVAL = newSVuv((size_t)context);
        } else {
            RETVAL = &PL_sv_undef;
        }
    OUTPUT:
        RETVAL

SV *
_duk_eval_wrapper(SV *, SV *)
    CODE:
        if (!ST(0)) {
            croak("Javascript context undefined.", 0);
        }
        duk_context *context = (duk_context *) SvUV(ST(0)); 
        if (!context) {
            croak("Javascript context null on function call.");
        }
        duk_idx_t top_index;
        if ( (top_index = duk_get_top_index(context)) != DUK_INVALID_INDEX) {
            duk_pop_n(context, top_index + 1);
        }
        duk_require_stack(context, 2);
        if (!ST(1)) {
            croak("Code to eval is undef.");
        }
        STRLEN code_len;
        char *code = SvPV(ST(1), code_len);
        duk_push_lstring(context, code, strlen(code));
        if ( duk_peval(context) != 0 ) {
            croak("Eval failed:\n%s\n%s\n", duk_safe_to_string(context, -1), duk_to_stacktrace(context, -1));
        }
        duk_size_t *lstring_len;
        const char * lstring = duk_get_lstring(context, -1, lstring_len);
        RETVAL = newSVpv(lstring, (size_t) lstring_len);
        top_index = duk_get_top_index(context);
        duk_pop_n(context, top_index+1);
    OUTPUT:
        RETVAL

SV *
_duk_call_function(SV *, SV *, ...) 
    CODE:
        if (!ST(0)) {
            croak("Context is undef.");
        }
        duk_context *context = (duk_context *) SvUV(ST(0)); 
        if (!context) {
            croak("Javascript context null on function call.");
        }
        STRLEN function_name_len;
        if (!ST(1)) {
            croak("Function name must be defined.");
        }
        char * function_name = SvPV(ST(1), function_name_len);
        if ( function_name_len == 0 ) {
            croak("Function name cannot be empty.");
        }
        duk_idx_t top_index;
        if ( (top_index = duk_get_top_index(context)) != DUK_INVALID_INDEX ) {
            duk_pop_n(context, top_index+1);
        }
        duk_require_stack(context, items+1);
        (void) duk_get_global_lstring(context, function_name, strlen(function_name));
        if (items > 2) {
            for ( int i = 2; i < items; i++) {
                SV *argument_SV = ST(i);
                if (!argument_SV) {
                    croak("Argument %d undefined.", i);
                }
                STRLEN argument_len;
                char *argument = SvPV(argument_SV, argument_len);
                duk_push_lstring(context, argument, strlen(argument));
            }
        }
        duk_size_t *lstring_len;
        duk_call(context, 1);
        const char * return_value = duk_get_lstring(context, -1, lstring_len);
        if ( (top_index = duk_get_top_index(context)) != DUK_INVALID_INDEX ) {
            duk_pop_n(context, top_index+1);
        }
        RETVAL = newSVpv(return_value, (size_t) lstring_len);
    OUTPUT:
        RETVAL

void
_duk_destroy_heap(SV *)
    CODE:
        duk_context *context = (duk_context *) SvUV(ST(0)); 
        if (!context) {
            croak("Cannot destroy something that is not a context.");
        }
        duk_destroy_heap(context);