/*
** $Id: lua.c,v 1.160.1.2 2007/12/28 15:32:23 roberto Exp $
** Lua stand-alone interpreter
** See Copyright Notice in lua.h
*/


// #include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "user_version.h"
#include "driver/console.h"
#include "esp_system.h"
#include "platform.h"

#define lua_c

#include "lua.h"

#include "lauxlib.h"
#include "lualib.h"
#include "legc.h"
#include "lflash.h"

lua_State *globalL = NULL;

lua_Load gLoad;
static const char *progname = LUA_PROGNAME;

static void l_message (const char *pname, const char *msg) {
#if defined(LUA_USE_STDIO)
  if (pname) fprintf(stderr, "%s: ", pname);
  fprintf(stderr, "%s\n", msg);
  fflush(stderr);
#else
  if (pname) luai_writestringerror("%s: ", pname);
  luai_writestringerror("%s\n", msg);
#endif
}


static int report (lua_State *L, int status) {
  if (status && !lua_isnil(L, -1)) {
    const char *msg = lua_tostring(L, -1);
    if (msg == NULL) msg = "(error object is not a string)";
    l_message(progname, msg);
    lua_pop(L, 1);
  }
  return status;
}


static int traceback (lua_State *L) {
  if (!lua_isstring(L, 1))  /* 'message' not a string? */
    return 1;  /* keep it intact */
  lua_getfield(L, LUA_GLOBALSINDEX, "debug");
  if (!lua_istable(L, -1) && !lua_isrotable(L, -1)) {
    lua_pop(L, 1);
    return 1;
  }
  lua_getfield(L, -1, "traceback");
  if (!lua_isfunction(L, -1) && !lua_islightfunction(L, -1)) {
    lua_pop(L, 2);
    return 1;
  }
  lua_pushvalue(L, 1);  /* pass error message */
  lua_pushinteger(L, 2);  /* skip this function and traceback */
  lua_call(L, 2, 1);  /* call debug.traceback */
  return 1;
}


static int docall (lua_State *L, int narg, int clear) {
  int status;
  int base = lua_gettop(L) - narg;  /* function index */
  lua_pushcfunction(L, traceback);  /* push traceback function */
  lua_insert(L, base);  /* put it under chunk and args */
  // signal(SIGINT, laction);
  status = lua_pcall(L, narg, (clear ? 0 : LUA_MULTRET), base);
  // signal(SIGINT, SIG_DFL);
  lua_remove(L, base);  /* remove traceback function */
  /* force a complete garbage collection in case of errors */
  if (status != 0) lua_gc(L, LUA_GCCOLLECT, 0);
  return status;
}


static void print_version (lua_State *L) {
  lua_pushliteral (L, "\n" NODE_VERSION " build " BUILD_DATE " powered by " LUA_RELEASE " on SDK ");
  lua_pushstring (L, SDK_VERSION);
  lua_concat (L, 2);
  const char *msg = lua_tostring (L, -1);
  l_message (NULL, msg);
  lua_pop (L, 1);
}


static int getargs (lua_State *L, char **argv, int n) {
  int narg;
  int i;
  int argc = 0;
  while (argv[argc]) argc++;  /* count total number of arguments */
  narg = argc - (n + 1);  /* number of arguments to the script */
  luaL_checkstack(L, narg + 3, "too many arguments to script");
  for (i=n+1; i < argc; i++)
    lua_pushstring(L, argv[i]);
  lua_createtable(L, narg, n + 1);
  for (i=0; i < argc; i++) {
    lua_pushstring(L, argv[i]);
    lua_rawseti(L, -2, i - n);
  }
  return narg;
}

static int dofsfile (lua_State *L, const char *name) {
  int status = luaL_loadfsfile(L, name) || docall(L, 0, 1);
  return report(L, status);
}

static int dolfsfile (lua_State *L, const char *name) {
  int status = 1;
  const char *code_fmt = "if node.flashindex('%s') then node.flashindex('%s')() end";
  char *module_name = strdup(name);
  unsigned name_len = strlen(name);
  unsigned code_length = strlen(code_fmt) + name_len*2 + 1;
  char *code_buf = malloc(code_length);

  if (code_buf && module_name) {
    char *dot = strrchr(module_name, '.');
    if (dot) {
      if (strstr(module_name, ".lua") == dot)
        *dot = 0;
    }
    snprintf(code_buf, code_length, code_fmt, module_name, module_name);
    status = luaL_dostring(L, code_buf);
    if (status)
      lua_pushfstring(L, "Failed to load %s from LFS", module_name);
  } else {
    lua_pushstring(L, "Failed to allocate memory");
  }

  if (module_name)
    free(module_name);
  if (code_buf)
    free(code_buf);
  return report(L, status);
}

static int dostring (lua_State *L, const char *s, const char *name) {
  int status = luaL_loadbuffer(L, s, strlen(s), name) || docall(L, 0, 1);
  return report(L, status);
}


static int dolibrary (lua_State *L, const char *name) {
  lua_getglobal(L, "require");
  lua_pushstring(L, name);
  return report(L, docall(L, 1, 1));
}

static const char *get_prompt (lua_State *L, int firstline) {
  const char *p;
  lua_getfield(L, LUA_GLOBALSINDEX, firstline ? "_PROMPT" : "_PROMPT2");
  p = lua_tostring(L, -1);
  if (p == NULL) p = (firstline ? LUA_PROMPT : LUA_PROMPT2);
  lua_pop(L, 1);  /* remove global */
  return p;
}


static int incomplete (lua_State *L, int status) {
  if (status == LUA_ERRSYNTAX) {
    size_t lmsg;
    const char *msg = lua_tolstring(L, -1, &lmsg);
    const char *tp = msg + lmsg - (sizeof(LUA_QL("<eof>")) - 1);
    if (strstr(msg, LUA_QL("<eof>")) == tp) {
      lua_pop(L, 1);
      return 1;
    }
  }
  return 0;  /* else... */
}


/* check that argument has no extra characters at the end */
#define notail(x)	{if ((x)[2] != '\0') return -1;}


static int collectargs (char **argv, int *pi, int *pv, int *pe) {
  int i;
  for (i = 1; argv[i] != NULL; i++) {
    if (argv[i][0] != '-')  /* not an option? */
        return i;
    switch (argv[i][1]) {  /* option */
      case '-':
        notail(argv[i]);
        return (argv[i+1] != NULL ? i+1 : 0);
      case '\0':
        return i;
      case 'i':
        notail(argv[i]);
        *pi = 1;  /* go through */
      case 'v':
        notail(argv[i]);
        *pv = 1;
        break;
      case 'e':
        *pe = 1;  /* go through */
      case 'm':   /* go through */
      case 'l':
        if (argv[i][2] == '\0') {
          i++;
          if (argv[i] == NULL) return -1;
        }
        break;
      default: return -1;  /* invalid option */
    }
  }
  return 0;
}


static int runargs (lua_State *L, char **argv, int n) {
  int i;
  for (i = 1; i < n; i++) {
    if (argv[i] == NULL) continue;
    lua_assert(argv[i][0] == '-');
    switch (argv[i][1]) {  /* option */
      case 'e': {
        const char *chunk = argv[i] + 2;
        if (*chunk == '\0') chunk = argv[++i];
        lua_assert(chunk != NULL);
        if (dostring(L, chunk, "=(command line)") != 0)
          return 1;
        break;
      }
      case 'm': {
        const char *limit = argv[i] + 2;
        int memlimit=0;
        if (*limit == '\0') limit = argv[++i];
        lua_assert(limit != NULL);
        memlimit = atoi(limit);
        lua_gc(L, LUA_GCSETMEMLIMIT, memlimit);
        break;
      }
      case 'l': {
        const char *filename = argv[i] + 2;
        if (*filename == '\0') filename = argv[++i];
        lua_assert(filename != NULL);
        if (dolibrary(L, filename))
          return 1;  /* stop if file fails */
        break;
      }
      default: break;
    }
  }
  return 0;
}


#ifndef LUA_INIT_STRING
#define LUA_INIT_STRING "@init.lua"
#endif

static int handle_luainit (lua_State *L) {
  const char *init = LUA_INIT_STRING;
  if (init[0] == '@') {
  #if CONFIG_NODEMCU_EMBEDDED_LFS_SIZE > 0
    int status = dolfsfile(L, init+1);
    if (status == 0)
      return status;
  #endif
    return dofsfile(L, init+1);
  } else
    return dostring(L, init, LUA_INIT);
}


struct Smain {
  int argc;
  char **argv;
  int status;
};


static int pmain (lua_State *L) {
  struct Smain *s = (struct Smain *)lua_touserdata(L, 1);
  char **argv = s->argv;
  int script;
  int has_i = 0, has_v = 0, has_e = 0;
  globalL = L;
  if (argv[0] && argv[0][0]) progname = argv[0];
  lua_gc(L, LUA_GCSTOP, 0);  /* stop collector during initialization */
  luaL_openlibs(L);  /* open libraries */
  lua_gc(L, LUA_GCRESTART, 0);
  print_version(L);
  s->status = handle_luainit(L);
  script = collectargs(argv, &has_i, &has_v, &has_e);
  if (script < 0) {  /* invalid args? */
    s->status = 1;
    return 0;
  }
  s->status = runargs(L, argv, (script > 0) ? script : s->argc);
  if (s->status != 0) return 0;
  return 0;
}

static void dojob(lua_Load *load);
static bool readline(lua_Load *load);

#ifdef LUA_RPC
int main (int argc, char **argv) {
#else
int lua_main (int argc, char **argv) {
#endif
  int status;
  struct Smain s;
  lua_State *L = lua_open();  /* create state */
  if (L == NULL) {
    l_message(argv[0], "cannot create state: not enough memory");
    return EXIT_FAILURE;
  }
  s.argc = argc;
  s.argv = argv;

  status = lua_cpcall(L, &pmain, &s);

  report(L, status);

  gLoad.L = L;
  gLoad.firstline = 1;
  gLoad.done = 0;
  gLoad.line = malloc(LUA_MAXINPUT);
  gLoad.len = LUA_MAXINPUT;
  gLoad.line_position = 0;
  gLoad.prmt = get_prompt(L, 1);

  dojob(&gLoad);

  NODE_DBG("Heap size:%d.\n",system_get_free_heap_size());
  legc_set_mode( L, EGC_ALWAYS, 4096 );
  // legc_set_mode( L, EGC_ON_MEM_LIMIT, 4096 );
  // lua_close(L);
  return (status || s.status) ? EXIT_FAILURE : EXIT_SUCCESS;
}

int lua_put_line(const char *s, size_t l) {
  if (s == NULL || ++l > LUA_MAXINPUT || gLoad.line_position > 0)
    return 0;
  memcpy(gLoad.line, s, l);
  gLoad.line[l] = '\0';
  gLoad.line_position = l;
  gLoad.done = 1;
  NODE_DBG("Get command: %s\n", gLoad.line);
  return 1;
}

void lua_handle_input (bool force)
{
  while (gLoad.L && (force || readline (&gLoad))) {
    NODE_DBG("Handle Input: first=%u, pos=%u, len=%u, actual=%u, line=%s\n", gLoad.firstline,
              gLoad.line_position, gLoad.len, strlen(gLoad.line), gLoad.line);
    dojob (&gLoad);
    force = false;
  }
}

void donejob(lua_Load *load){
  lua_close(load->L);
}

static void dojob(lua_Load *load){
  size_t l, rs;
  int status;
  char *b = load->line;
  lua_State *L = load->L;

  const char *oldprogname = progname;
  progname = NULL;
  
  do{
    if(load->done == 1){
      l = strlen(b);
      if (l > 0 && b[l-1] == '\n')  /* line ends with newline? */
        b[l-1] = '\0';  /* remove it */
      if (load->firstline && b[0] == '=')  /* first line starts with `=' ? */
        lua_pushfstring(L, "return %s", b+1);  /* change it to `return' */
      else
        lua_pushstring(L, b);
      if(load->firstline != 1){
        lua_pushliteral(L, "\n");  /* add a new line... */
        lua_insert(L, -2);  /* ...between the two lines */
        lua_concat(L, 3);  /* join them */
      }

      status = luaL_loadbuffer(L, lua_tostring(L, 1), lua_strlen(L, 1), "=stdin");
      if (!incomplete(L, status)) {  /* cannot try to add lines? */
        lua_remove(L, 1);  /* remove line */
        if (status == 0) {
          status = docall(L, 0, 0);
        }
        report(L, status);
        if (status == 0 && lua_gettop(L) > 0) {  /* any result to print? */
          lua_getglobal(L, "print");
          lua_insert(L, 1);
          if (lua_pcall(L, lua_gettop(L)-1, 0, 0) != 0)
            l_message(progname, lua_pushfstring(L,
                                   "error calling " LUA_QL("print") " (%s)",
                                   lua_tostring(L, -1)));
        }
        load->firstline = 1;
        load->prmt = get_prompt(L, 1);
        lua_settop(L, 0);
        /* force a complete garbage collection in case of errors */
        if (status != 0) lua_gc(L, LUA_GCCOLLECT, 0);
      } else {
        load->firstline = 0;
        load->prmt = get_prompt(L, 0);
      }
    }
  }while(0);

  progname = oldprogname;

  load->done = 0;
  load->line_position = 0;
  memset(load->line, 0, load->len);
  printf(load->prmt);
  fflush (stdout);
}

extern bool uart_on_data_cb(unsigned id, const char *buf, size_t len);
extern bool uart0_echo;
extern bool run_input;
extern uart_status_t uart_status[];
static char last_nl_char = '\0';
static bool readline(lua_Load *load){
  // NODE_DBG("readline() is called.\n");
  bool need_dojob = false;
  char ch;
  uart_status_t *us = & uart_status[CONSOLE_UART]; 
  while (console_getc(&ch))
  {
    if(run_input)
    {
      char tmp_last_nl_char = last_nl_char;
      // reset marker, will be finally set below when newline is processed
      last_nl_char = '\0';

      /* handle CR & LF characters
         filters second char of LF&CR (\n\r) or CR&LF (\r\n) sequences */
      if ((ch == '\r' && tmp_last_nl_char == '\n') || // \n\r sequence -> skip \r
          (ch == '\n' && tmp_last_nl_char == '\r'))   // \r\n sequence -> skip \n
      {
        continue;
      }

      /* backspace key */
      else if (ch == 0x7f || ch == 0x08)
      {
        if (load->line_position > 0)
        {
          if(uart0_echo) putchar(0x08);
          if(uart0_echo) putchar(' ');
          if(uart0_echo) putchar(0x08);
          load->line_position--;
        }
        load->line[load->line_position] = 0;
        continue;
      }
      /* EOT(ctrl+d) */
      // else if (ch == 0x04)
      // {
      //   if (load->line_position == 0)
      //     // No input which makes lua interpreter close 
      //     donejob(load);
      //   else
      //     continue;
      // }

      /* end of line */
      if (ch == '\r' || ch == '\n')
      {
        last_nl_char = ch;

        load->line[load->line_position] = 0;
        if(uart0_echo) putchar('\n');
        uart_on_data_cb(CONSOLE_UART, load->line, load->line_position);
        if (load->line_position == 0)
        {
          /* Get a empty line, then go to get a new line */
          printf(load->prmt);
          fflush (stdout);
        } else {
          load->done = 1;
          need_dojob = true;
        }
        continue;
      }

      /* other control character or not an acsii character */
      // if (ch < 0x20 || ch >= 0x80)
      // {
      //   continue;
      // }
      
      /* echo */
      if(uart0_echo) putchar(ch);

          /* it's a large line, discard it */
      if ( load->line_position + 1 >= load->len ){
        load->line_position = 0;
      }
    }

    load->line[load->line_position] = ch;
    load->line_position++;

    if(!run_input)
    {
      if( ((us->need_len!=0) && (load->line_position >= us->need_len)) || \
        (load->line_position >= load->len) || \
        ((us->end_char>=0) && ((unsigned char)ch==(unsigned char)us->end_char)) )
      {
        uart_on_data_cb(CONSOLE_UART, load->line, load->line_position);
        load->line_position = 0;
      }
    }

    ch = 0;
  }
  
  if( (load->line_position > 0) && (!run_input) && (us->need_len==0) && (us->end_char<0) )
  {
    uart_on_data_cb(CONSOLE_UART, load->line, load->line_position);
    load->line_position = 0;
  }

  return need_dojob;
}