/* -*-c-*- -------------- mix_parser.c :
 * Implementation of the functions declared in mix_parser.h and 
 * xmix_parser.h
 * ------------------------------------------------------------------
 * Copyright (C) 2000, 2001 Free Software Foundation, Inc.
 *  
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *  
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *  
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *  
 */

#include <string.h>

#include "mix.h"
#include "mix_code_file.h"
#include "xmix_parser.h"

/* The flex-generated scanner, according to file mix_scanner.l */
extern mix_parser_err_t
mix_flex_scan (mix_parser_t *parser);

/*------------ mixparser.h functions -------------------------------------*/

/* error messages */
static const gchar * const ERR_MESSAGE_[] = {
  N_("successful compilation"),
  N_("file not yet compiled"),
  N_("internal error"),
  N_("unable to open MIX source file"),
  N_("unable to open MIX output file"),
  N_("unexpected end of file"),
  N_("invalid location field"),
  N_("duplicated symbol"),
  N_("symbol too long"),
  N_("missing operator field"),
  N_("unexpected location symbol"),
  N_("invalid address field"),
  N_("invalid index field"),
  N_("invalid f-specification"),
  N_("invalid operation field"),
  N_("invalid expression"),
  N_("undefined symbol"),
  N_("mismatched parenthesis"),
  N_("unexpected f-specfication"),
  N_("missing symbol name"),
  N_("symbol is an instruction name"),
  N_("failed write access to code file"),
  N_("operand of ALF pseudo instruction has less than 5 chars"),
  N_("operand of ALF pseudo instruction has more than 5 chars")
};

static const guint NO_OF_MESSAGES_ = sizeof(ERR_MESSAGE_)/sizeof (gchar*);

const gchar *
mix_parser_err_string (mix_parser_err_t error)
{
  return (error < NO_OF_MESSAGES_) ? _(ERR_MESSAGE_[error]) : NULL;
}

guint 
mix_parser_err_count (const mix_parser_t *parser)
{
  return (parser) ? parser->err_count : 0;
}

guint 
mix_parser_warning_count (const mix_parser_t *parser)
{
  return (parser) ? parser->warn_count : 0;
}

const gchar *
mix_parser_src_file_base_name (const mix_parser_t *parser)
{
  return (parser) ? mix_file_base_name (parser->in_file) : NULL;
}

const gchar *
mix_parser_src_file_extension (const mix_parser_t *parser)
{
  return (parser) ? mix_file_extension (parser->in_file) : NULL;
}


/* Create/destroy a mix_parser */
/* compare function for the table of ins */
static gint
compare_shorts_ (gconstpointer s1, gconstpointer s2)
{
  mix_short_t a = (mix_short_t)GPOINTER_TO_UINT(s1);
  mix_short_t b = (mix_short_t)GPOINTER_TO_UINT (s2);
  if ( mix_short_sign (a) == mix_short_sign (b) )
    return mix_short_magnitude (a) - mix_short_magnitude (b);
  else if ( mix_short_magnitude (a) == 0 && mix_short_magnitude (b) == 0 )
    return 0;
  else if ( mix_short_is_positive (a) ) 
    return 1;
  return -1;
}

mix_parser_t *
mix_parser_new (const gchar *in_file)
{
  mix_parser_t *result;
  mix_file_t *f = mix_file_new_with_def_ext (in_file, mix_io_READ, 
					     MIX_SRC_DEFEXT);
  
  if ( f == NULL ) return NULL;
  result = g_new (mix_parser_t, 1);
  result->symbol_table = mix_symbol_table_new ();
  result->ls_table = mix_symbol_table_new ();
  result->cur_ls = 0;
  result->future_refs = g_hash_table_new (g_str_hash, g_str_equal);
  result->ins_table = g_tree_new (compare_shorts_);
  if ( result->symbol_table == NULL || result->future_refs == NULL
       || result->ins_table == NULL || result->ls_table == NULL )
    {
      mix_symbol_table_delete (result->symbol_table);
      mix_symbol_table_delete (result->ls_table);
      g_hash_table_destroy (result->future_refs);
      g_tree_destroy (result->ins_table);
      mix_file_delete (f);
      g_free (result);
      g_warning (_("No system resources"));
      return NULL;
    }
  result->in_file = f;
  result->loc_count = MIX_SHORT_ZERO;
  result->status = MIX_PERR_NOCOMP;
  result->err_line = 0;
  result->err_count = 0;
  result->warn_count = 0;
  return result;
}

static void
delete_list_vals_ (gpointer key, gpointer value, gpointer data)
{
  g_free (key);
  g_slist_free ((GSList*)value);
}

static int
delete_tree_vals_ (gpointer key, gpointer value, gpointer data)
{
  g_free (value);
  return FALSE;
}

void
mix_parser_delete (mix_parser_t *parser)
{
  g_return_if_fail (parser != NULL);
  /* clear the GSList values of future_refs and its keys */
  g_hash_table_foreach (parser->future_refs, delete_list_vals_, NULL);
  /* clear the ins_node_'s of the ins tree */
  g_tree_traverse (parser->ins_table, delete_tree_vals_, G_IN_ORDER, NULL);
  /* destroy the tree and hash tables */
  g_tree_destroy (parser->ins_table);
  mix_symbol_table_delete (parser->symbol_table);
  mix_symbol_table_delete (parser->ls_table);
  g_hash_table_destroy (parser->future_refs);
  mix_file_delete (parser->in_file);
  g_free (parser);
}

/* Compile a mix source file */
static gboolean
undef_warning_ (gpointer symbol, gpointer value, gpointer data)
{
  mix_parser_log_error ((mix_parser_t *)data, MIX_PERR_UNDEF_SYM, 1,
			(const gchar *)symbol, TRUE);
  /* move the symbol to the symbol table */
  mix_symbol_table_insert_static (((mix_parser_t *)data)->symbol_table,
				  symbol, MIX_WORD_ZERO);
  return TRUE;
}

static void
update_future_refs_value_ (mix_parser_t *parser, const gchar *name,
			   mix_short_t value)
{
  GSList *list = NULL;
  gpointer key;
  
  g_assert (parser != NULL && name != NULL);
  if ( g_hash_table_lookup_extended (parser->future_refs, name, &key, 
				     (gpointer *)&list) )
    {
      GSList *tmp = list;
      ins_node_ *node;
      while ( tmp != NULL )
	{
	  node = 
	    (ins_node_ *)g_tree_lookup (parser->ins_table,tmp->data);
	  g_assert (node);
	  if (mix_get_ins_address (node->ins) == 1) {
	    value = mix_short_negative (value);
	    node->ins = mix_word_set_field (node->ins,
					    MIX_WORD_ZERO,
					    mix_fspec_new (1,2));
	  }
	  mix_word_add_address (node->ins, value);
	  g_tree_insert (parser->ins_table, tmp->data, (gpointer)node);
	  tmp = g_slist_next (tmp);
	}
      g_hash_table_remove (parser->future_refs, name);
      g_free (key);
      g_slist_free (list);
    }
}

#define update_future_refs_(parser,name) \
  update_future_refs_value_(parser, name, (parser)->loc_count);

static void
update_ls_ (gpointer symbol, gpointer value, gpointer parser)
{ /* add an instruction on current location and update refs to it */
  mix_ins_t ins;
  mix_word_t w = (mix_word_t) GPOINTER_TO_UINT (value);
  mix_parser_t *par = (mix_parser_t *) parser;
  
  mix_word_to_ins_uncheck (w, ins);
  mix_parser_add_ins (par, &ins, 0);
  update_future_refs_ (par, (const gchar *)symbol);
  par->loc_count++;
}

mix_parser_err_t
mix_parser_compile (mix_parser_t *parser)
{
  g_return_val_if_fail (parser != NULL, MIX_PERR_INTERNAL);
  g_return_val_if_fail (parser->in_file != NULL, MIX_PERR_NOIN);
  g_return_val_if_fail (parser->symbol_table != NULL, MIX_PERR_INTERNAL);
  g_return_val_if_fail (parser->future_refs != NULL, MIX_PERR_INTERNAL);
  g_return_val_if_fail (parser->ins_table != NULL, MIX_PERR_INTERNAL);
  
  parser->status = mix_flex_scan (parser);
  if ( parser->status == MIX_PERR_OK )
    {
      mix_symbol_table_foreach (parser->ls_table, update_ls_, 
				(gpointer)parser);
      g_hash_table_foreach_remove (parser->future_refs, 
				   undef_warning_, (gpointer)parser);
    }
  
  return parser->status;
}

/* Write a compiled source to a code file */
struct write_code_context_
{
  mix_code_file_t *file;
  mix_parser_t *parser;
};

static gint
write_code_ (gpointer address, gpointer ins_node, gpointer context)
{
  mix_ins_desc_t desc;
  struct write_code_context_ *cntx = (struct write_code_context_ *)context;
  desc.ins = ((ins_node_ *)ins_node)->ins;
  desc.lineno = ((ins_node_ *)ins_node)->lineno;
  desc.address = (mix_address_t)GPOINTER_TO_UINT (address);
  if ( mix_code_file_write_ins (cntx->file, &desc) )
    return FALSE;
  else 
    {
      cntx->parser->status = MIX_PERR_NOWRITE;
      return TRUE;
    }
}

mix_parser_err_t
mix_parser_write_code (mix_parser_t *parser, const gchar *code_file, 
		       gboolean debug)
{
  struct write_code_context_ context;
  const gchar *cfname = (code_file) ?
    code_file : mix_file_base_name (parser->in_file);
  gchar *source_path;
    
  g_return_val_if_fail (parser != NULL, MIX_PERR_INTERNAL);
  if  (parser->status != MIX_PERR_OK ) return parser->status;
  context.parser = parser;
  if (!g_path_is_absolute (mix_file_base_name (parser->in_file)))
    {
      gchar *dir = g_get_current_dir ();
      source_path = g_strconcat (dir, G_DIR_SEPARATOR_S,
				 mix_file_base_name (parser->in_file), NULL);
      g_free (dir);
    }
  else
    source_path = g_strdup (mix_file_base_name (parser->in_file));
    
  context.file = mix_code_file_new_write (cfname, parser->start, source_path,
					  debug, parser->symbol_table);
  g_free (source_path);

  if (context.file == NULL) return MIX_PERR_NOOUT;
  g_tree_traverse (parser->ins_table, write_code_, 
		   G_IN_ORDER, (gpointer)&context);
  mix_code_file_delete (context.file);
  return parser->status;
}

/* Produce a listing file summarising the compilation */
static gint
write_listing_ (gpointer address, gpointer ins, gpointer context)
{
  guint k;
  FILE *file = (FILE *)context;
  ins_node_ *ins_node = (ins_node_ *)ins;
  mix_ins_t instruct;
  gchar *instext = NULL;

  mix_ins_id_t id = mix_word_to_ins (ins_node->ins, &instruct);
  if (id != mix_INVALID_INS)
    instext = mix_ins_to_string (&instruct);
  fprintf (file, "%d\t%s ", GPOINTER_TO_INT (address),
	   mix_word_is_negative (ins_node->ins)? "-":"+");
  for ( k = 1; k < 6; ++k )
    fprintf (file, "%02d ", mix_word_get_byte (ins_node->ins, k));
  fprintf (file, _("\t%s\t(line %d)\n"), instext? instext:"--DATA--",
	   ins_node->lineno);
  if (instext) g_free (instext);
  return FALSE;
}

mix_parser_err_t
mix_parser_write_listing (mix_parser_t *parser, const gchar *list_file)
{
  FILE *file;
  mix_file_t *mfile;
  const gchar *name;
  
  g_return_val_if_fail (parser != NULL, MIX_PERR_INTERNAL);
  if (parser->status != MIX_PERR_OK ) return parser->status;
  name = (list_file) ? list_file : mix_file_base_name (parser->in_file);
  mfile =  mix_file_new_with_def_ext (name, mix_io_WRITE, MIX_LIST_DEFEXT);
  if ( mfile == NULL ) return MIX_PERR_NOOUT;
  file = mix_file_to_FILE (mfile);
  fprintf (file, _("*** %s%s: compilation summary ***\n\n"), 
	   mix_file_base_name (parser->in_file), 
	   mix_file_extension (parser->in_file));
  fputs ( _("*** Address / Compiled word / Symbolic rep / Source file line\n"),
	  file);
  g_tree_traverse (parser->ins_table, write_listing_, 
		   G_IN_ORDER, (gpointer)file);
  fprintf (file, _("\n*** Start address: %d\n"), 
	   mix_short_magnitude (parser->start));
  fprintf (file, _("\n*** Symbol table\n"));
  mix_symbol_table_print (parser->symbol_table, MIX_SYM_ROWS, file, TRUE);
  fprintf (file, _("\n*** End of summary ***\n"));
  mix_file_delete (mfile);
  return parser->status;
}

/* load a virtual machine's memory with the contents of a compiled file */
static gint
load_vm_ (gpointer address, gpointer ins, gpointer vm)
{
  mix_vm_set_addr_contents ((mix_vm_t*)vm,
			    (mix_address_t)GPOINTER_TO_UINT (address), 
			    ((ins_node_ *)ins)->ins);
  return FALSE;
}

mix_parser_err_t
mix_parser_load_vm (const mix_parser_t *parser, mix_vm_t *vm)
{
  g_return_val_if_fail (parser != NULL, MIX_PERR_INTERNAL);
  g_return_val_if_fail (vm != NULL, MIX_PERR_INTERNAL);
  g_return_val_if_fail (parser->status == MIX_PERR_OK, parser->status);
  mix_vm_reset (vm);
  g_tree_traverse (parser->ins_table, load_vm_, G_IN_ORDER, (gpointer)vm);
  mix_vm_set_start_addr (vm, parser->start);
  return parser->status;
}



/*------------ xmiparser.h functions -------------------------------------*/
/* functions to manipulate mix_parser_t during compilation */


/* symbol table */
/* Define a new symbol with value equal to the current loc_count
 * and update future refs to this symbol
 */
mix_parser_err_t
mix_parser_define_symbol_here (mix_parser_t *parser, const gchar *name)
{
  mix_word_t value = mix_short_to_word_fast (parser->loc_count);
  return mix_parser_define_symbol_value (parser, name, value);
}

mix_parser_err_t
mix_parser_define_symbol_value (mix_parser_t *parser, const gchar *name,
				mix_word_t value)
{
  g_assert (parser != NULL && name != NULL);  
  
  switch (mix_symbol_table_add (parser->symbol_table, name, value))
    {
    case MIX_SYM_OK: 
      if ( parser->status == MIX_PERR_NOCOMP ) 
	update_future_refs_value_ (parser, name, value);
      return MIX_PERR_OK;
    case MIX_SYM_LONG: return MIX_PERR_LONG_SYMBOL;
    case MIX_SYM_DUP: return MIX_PERR_DUP_SYMBOL;
    default: return MIX_PERR_INTERNAL;
    }
}

/* Obtain the value of a symbol */
void
mix_parser_set_future_ref (mix_parser_t *parser, const gchar *name)
{
  const gchar *nname = name;
  GSList *list;

  g_assert (parser != NULL && name != NULL);

  if ( parser->status == MIX_PERR_NOCOMP )
    {
      list =  g_hash_table_lookup (parser->future_refs, name);
      if ( list == NULL ) nname = g_strdup (name);
      list = g_slist_prepend (list, (gpointer)((guint)parser->loc_count));
      g_hash_table_insert (parser->future_refs, (gpointer)nname, list);
    }
}

/* Redefine the value of a local symbol as the current loc_count */
void
mix_parser_manage_local_symbol (mix_parser_t *parser, const gchar *name,
				mix_short_t value)
{
  gchar ref[3];
  ref[2] = 0;
    
  g_assert (parser != NULL && name != NULL);
  g_assert (strlen(name) == 2);
  
  switch (name[1])
    {
    case 'f': case 'F':
      mix_parser_set_future_ref (parser, name);
      break;
    case 'h': case 'H':
      ref[0] = name[0];
      ref[1] = 'F';
      if ( parser->status == MIX_PERR_NOCOMP ) 
	update_future_refs_value_ (parser, ref, value);
      ref[1] = 'B';
      mix_symbol_table_insert (parser->symbol_table, ref, 
			       mix_short_to_word_fast (value));
      break;
    default:
      return;
    }
}

/* Literal strings symbols */
void
mix_parser_define_ls (mix_parser_t *parser, mix_word_t value)
{
  gchar *name = g_strdup_printf ("%05d", parser->cur_ls++);
  mix_symbol_table_add (parser->ls_table, name, value);
  mix_parser_set_future_ref (parser, name);
  g_free (name);
}

/* Compilation */
void
mix_parser_add_ins (mix_parser_t *parser, const mix_ins_t *new_ins, 
		    guint lineno)
{
  g_assert (parser != NULL && new_ins != NULL);
  mix_parser_add_raw (parser, mix_ins_to_word_uncheck (*new_ins), lineno);
}

void
mix_parser_add_raw (mix_parser_t *parser, mix_word_t word, guint lineno)
{
  g_assert (parser != NULL);
  if ( parser->status == MIX_PERR_NOCOMP || parser->status == MIX_PERR_OK )
    {
      ins_node_ *node = g_new (ins_node_, 1);
      node->ins = word;
      node->lineno = lineno;
      g_tree_insert (parser->ins_table, (gpointer)((guint)parser->loc_count),
		     (gpointer)node);
    }
}

/* Error handling */
void 
mix_parser_log_error (mix_parser_t *parser, mix_parser_err_t error,
		      gint lineno, const gchar *comment, gboolean warn)
{
  g_assert (parser != NULL);
  if ( warn )
    parser->warn_count += 1;
  else
    {
      parser->err_count += 1;
      parser->err_line = lineno;
      parser->status = error;
    }
    
  fprintf (stderr, "%s%s:%d: %s: %s",
	   mix_file_base_name (parser->in_file), 
	   mix_file_extension (parser->in_file),
	   lineno, warn ? _("warning"):_("error"), _(ERR_MESSAGE_[error]));

  if (comment != NULL)
    fprintf (stderr, ": %s\n", comment);
  else
    fputs ("\n", stderr);
}