/*
  =======================================================================================
  File: 
        dtpython.c

  Description: 
        The implementation of the interface for using Python in C code.

  Author:
       Delphi Tang (唐佐林)
       http://www.dt4sw.com/

  Revision History:
       V0.1.0 (Initial Version)
  =======================================================================================
*/


#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include "py/compile.h"
#include "py/runtime.h"
#include "py/repl.h"
#include "py/gc.h"
#include "py/mperrno.h"
#include "lib/utils/pyexec.h"

#if MICROPY_ENABLE_COMPILER
static void do_str(const char *src, mp_parse_input_kind_t input_kind) {
    nlr_buf_t nlr;
    if (nlr_push(&nlr) == 0) {
        mp_lexer_t *lex = mp_lexer_new_from_str_len(MP_QSTR__lt_stdin_gt_, src, strlen(src), 0);
        qstr source_name = lex->source_name;
        mp_parse_tree_t parse_tree = mp_parse(lex, input_kind);
        mp_obj_t module_fun = mp_compile(&parse_tree, source_name, true);
        mp_call_function_0(module_fun);
        nlr_pop();
    } else {
        // uncaught exception
        mp_obj_print_exception(&mp_plat_print, (mp_obj_t)nlr.ret_val);
    }
}

static void do_file(const char *filename) {
    FILE* fp = fopen(filename, "r");

    if( fp != NULL )
    {
        char* buf = NULL;
        long len = 0;

        fseek(fp, 0, SEEK_END);

        len = ftell(fp);

        fseek(fp, 0, SEEK_SET);

        if( (buf = (char*)malloc(len + 1)) != NULL )
        {
            len = fread(buf, 1, len, fp);
            buf[len] = 0;

            do_str(buf, MP_PARSE_FILE_INPUT);
        }

        free(buf);
    }

    fclose(fp);
}
#endif

static char *stack_top;
#if MICROPY_ENABLE_GC
static char heap[10240];
#endif

#if MICROPY_ENABLE_GC
void gc_collect(void) {
    // WARNING: This gc_collect implementation doesn't try to get root
    // pointers from CPU registers, and thus may function incorrectly.
    void *dummy;
    gc_collect_start();
    gc_collect_root(&dummy, ((mp_uint_t)stack_top - (mp_uint_t)&dummy) / sizeof(mp_uint_t));
    gc_collect_end();
    gc_dump_info();
}
#endif

void nlr_jump_fail(void *val) {
    while (1) {
        ;
    }
}

mp_lexer_t *mp_lexer_new_from_file(const char *filename) {
    mp_raise_OSError(MP_ENOENT);
}

mp_import_stat_t mp_import_stat(const char *path) {
    return MP_IMPORT_STAT_NO_EXIST;
}

mp_obj_t mp_builtin_open(size_t n_args, const mp_obj_t *args, mp_map_t *kwargs) {
    return mp_const_none;
}

MP_DEFINE_CONST_FUN_OBJ_KW(mp_builtin_open_obj, 1, mp_builtin_open);

void DTPython_Init()
{
    int stack_dummy;
    stack_top = (char *)&stack_dummy;

    gc_init(heap, heap + sizeof(heap));

    mp_init();
}

void DTPython_RunFile(const char* file)
{
    if(file != NULL)
    {
        do_file(file);
    }
}

void DTPython_RunCode(const char* statement)
{
    if( statement != NULL )
    {
        do_str(statement, MP_PARSE_FILE_INPUT);
    }
}

void DTPython_Deinit()
{
    mp_deinit();
}