/** \file parser.c

The fish parser. Contains functions for parsing code.

*/

#include <stdlib.h>
#include <stdio.h>
#include <wchar.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <termios.h>
#include <pwd.h>
#include <dirent.h>
#include <signal.h>

#include "config.h"
#include "util.h"
#include "common.h"
#include "wutil.h"
#include "proc.h"
#include "parser.h"
#include "tokenizer.h"
#include "exec.h"
#include "wildcard.h"
#include "function.h"
#include "builtin.h"
#include "builtin_help.h"
#include "env.h"
#include "expand.h"
#include "reader.h"
#include "sanity.h"
#include "env_universal.h"

/** Length of the lineinfo string used for describing the current tokenizer position */
#define LINEINFO_SIZE 128

/**
   Maximum number of block levels in code. This is not the same as
   maximum recursion depth, this only has to do with how many block
   levels are legal in the source code, not at evaluation.
*/
#define BLOCK_MAX_COUNT 64

/**
   Maximum number of function calls, i.e. recursion depth.
*/
#define MAX_RECURSION_DEPTH 128

/**
   Error message for improper use of the exec builtin
*/
#define EXEC_ERR_MSG L"this command can not be used in a pipeline"

/**
   Error message for tokenizer error. The tokenizer message is
   appended to this message.
*/
#define TOK_ERR_MSG L"Tokenizer error"

/**
   Error message for short circut command error.
*/
#define COND_ERR_MSG L"Short circut command requires additional command"

/**
   Error message on reaching maximum recusrion depth
*/
#define RECURSION_ERR_MSG L"Maximum recursion depth reached. Accidental infinite loop?"

/**
   Error message on reaching maximum number of block calls
*/
#define BLOCK_ERR_MSG L"Maximum number of nested blocks reached."

/**
   Error message on missing 'end'
*/
#define END_ERR_MSG L"Block missing 'end'"

/**
   Error message on pipe/bg character without command
*/
#define CMD_ERR_MSG L"Expected command"

/** Last error code */
int error_code;

/** Position of last error */

static int err_pos;

/** Description of last error */
static wchar_t err_str[256];

/** Pointer to the current tokenizer */
static tokenizer *current_tokenizer;

/** String for representing the current line */
static wchar_t lineinfo[LINEINFO_SIZE];

/** This is the position of the beginning of the currently parsed command */
static int current_tokenizer_pos;

/** The current innermost block */
block_t *current_block=0;

/** List of called functions, used to help prevent infinite recursion */
static array_list_t forbidden_function;

/**
   String index where the current job started.
*/
static int job_start_pos;

io_data_t *block_io;

/**
   List of all profiling data
*/
static array_list_t profile_data;

static int eval_level=-1;

static int parse_job( process_t *p,
					  job_t *j,
					  tokenizer *tok );

typedef struct
{
	int exec, parse, level, skipped;
	wchar_t *cmd;
} profile_element_t;


int block_count( block_t *b )
{
	if( b==0)
		return 0;
	return( block_count(b->outer)+1);
}


void parser_push_block( int type )
{
	block_t *new = malloc( sizeof( block_t ));

//	debug( 2, L"Block push %ls %d\n", bl[type], block_count( current_block)+1 );
	new->outer = current_block;
	new->type = (current_block && current_block->skip)?FAKE:type;

	new->skip=current_block?current_block->skip:0;

	new->loop_status=LOOP_NORMAL;

	current_block = new;

	if( (new->type != FUNCTION_DEF) && 
		(new->type != FAKE) && 
		(new->type != OR) && 
		(new->type != AND) && 
		(new->type != TOP) )
	{
		env_push( type == FUNCTION_CALL );
	}
}

void parser_pop_block()
{
//	debug( 2, L"Block pop %ls %d\n", bl[current_block->type], block_count(current_block)-1 );

	if( (current_block->type != FUNCTION_DEF ) && 
		(current_block->type != FAKE) && 
		(current_block->type != OR) && 
		(current_block->type != AND) && 
		(current_block->type != TOP) )
	{
		env_pop();
	}
	
	switch( current_block->type)
	{
		case FOR:
		{
			free( current_block->for_variable );
			al_foreach( &current_block->for_vars, 
						(void (*)(const void *))&free );
			al_destroy( &current_block->for_vars );
			break;
		}

		case SWITCH:
		{
			free( current_block->switch_value );
			break;
		}

		case FUNCTION_DEF:
		{
			free( current_block->function_name );
			free( current_block->function_description );
			break;
		}

	}

	block_t *old = current_block;
	current_block = current_block->outer;
	free( old );
}

wchar_t *parser_get_block_desc( int block )
{
	switch( block )
	{
		case WHILE:
			return L"while block";
			
		case FOR:
			return L"for block";
			
		case IF:
			return L"'if' conditional block";

		case FUNCTION_DEF:
			return L"function definition block";
			
		case FUNCTION_CALL:
			return L"fuction invocation block";
			
		case SWITCH:
			return L"switch block";
			
		case FAKE:
			return L"unexecutable block";
			
		case TOP:
			return L"global root block";
			
		case SUBST:
			return L"command substitution block";
			
		case BEGIN:
			return L"unconditional block";
			
		case AND:
			return L"'and' conditional command";
			
		case OR:
			return L"'or' conditional command";
			
		default:
			return L"unknown/invalid block";
	}

}


int parser_is_subcommand( const wchar_t *cmd )
{
	return contains_str( cmd,
						 L"command", 
						 L"builtin", 
						 L"while",
						 L"exec",
						 L"if",
						 L"and",
						 L"or",
						 L"not",
						 0 );
}

/**
   Test if the specified string is command that opens a new block
*/

static int parser_is_block( wchar_t *word)
{
	return contains_str( word, 
						 L"for",
						 L"while", 
						 L"if", 
						 L"function",
						 L"switch", 
						 L"begin",
						 0 );
}

int parser_is_reserved( wchar_t *word)
{
	return parser_is_block(word) ||
		parser_is_subcommand( word ) ||
		contains_str( word, 
					  L"end", 
					  L"case", 
					  L"else", 
					  L"return",
					  L"continue",
					  L"break",
					  0 );
}

int parser_is_pipe_forbidden( wchar_t *word )
{
	return contains_str( word,
						 L"exec",
						 L"case", 
						 L"break",
						 L"return", 
						 L"continue", 
						 0 );
}

static const wchar_t *parser_find_end( const wchar_t * buff ) 
{
	tokenizer tok;
	int had_cmd=0;
	int count = 0;
	int error=0;
	int mark=0;
	
	for( tok_init( &tok, buff, 0 );
		 tok_has_next( &tok ) && !error;
		 tok_next( &tok ) )
	{
		int last_type = tok_last_type( &tok );
		switch( last_type )
		{
			case TOK_STRING:
			{
				if( !had_cmd )
				{
					if( wcscmp(tok_last(&tok), L"end")==0)
					{
						count--;
					}
					else if( parser_is_block( tok_last(&tok) ) )
					{
						count++;
					}

					if( count < 0 )
					{
						error = 1;
					}
					had_cmd = 1;
				}
				break;
			}
			
			case TOK_END:
			{
				had_cmd = 0;
				break;
			}
			
			case TOK_PIPE:
			case TOK_BACKGROUND:
			{
				if( had_cmd )
				{
					had_cmd = 0;
				}
				else
				{
					error = 1;
				}
				break;
				
			}

			case TOK_ERROR:
				error = 1;
				break;

			default:
				break;
				
		}		
		if(!count)
		{
			tok_next( &tok );			
			mark = tok_get_pos( &tok );			
			break;		
		}
		
	}
	
	tok_destroy( &tok );	
	if(!count && !error){

		return buff+mark;
	}
	return 0;
	
}

wchar_t *parser_cdpath_get( wchar_t *dir )
{
	wchar_t *res = 0;

	if( !dir )
		return 0;


	if( dir[0] == L'/' )
	{
		struct stat buf;
		if( wstat( dir, &buf ) == 0 )
		{
			if( S_ISDIR(buf.st_mode) )
			{
				res = wcsdup( dir );
			}
		}
	}
	else
	{
		wchar_t *path = env_get(L"CDPATH");

		if( path == 0 )
		{
			path = L".";
		}

		wchar_t *path_cpy = wcsdup( path );
		wchar_t *nxt_path = path;
		wchar_t *state;
		wchar_t *whole_path;

		if( (path_cpy==0) )
		{
			die_mem();			
		}

		for( nxt_path = wcstok( path_cpy, ARRAY_SEP_STR, &state );
			 nxt_path != 0;
			 nxt_path = wcstok( 0, ARRAY_SEP_STR, &state) )
		{
			wchar_t *expanded_path = expand_tilde( wcsdup(nxt_path) );

//			debug( 2, L"woot %ls\n", expanded_path );

			int path_len = wcslen( expanded_path );
			if( path_len == 0 )
			{
				free(expanded_path );
				continue;
			}

			whole_path = 
				wcsdupcat2( expanded_path,
							( expanded_path[path_len-1] != L'/' )?L"/":L"",
							dir, 0 );

			free(expanded_path );

			struct stat buf;
			if( wstat( whole_path, &buf ) == 0 )
			{
				if( S_ISDIR(buf.st_mode) )
				{
					res = whole_path;
					break;
				}
			}
			free( whole_path );

		}
		free( path_cpy );
	}
	return res;
}


void parser_forbid_function( wchar_t *function )
{
/*
  if( function )
  debug( 2, L"Forbid %ls\n", function );
*/
	al_push( &forbidden_function, function?wcsdup(function):0 );
}

void parser_allow_function()
{
/*
  if( al_peek( &forbidden_function) )
  debug( 2, L"Allow %ls\n", al_peek( &forbidden_function)  );
*/
	free( (void *) al_pop( &forbidden_function ) );
}

void error( int ec, const wchar_t *str, int p )
{
	error_code = ec;
	wcsncpy( err_str, str, 256 );
	err_pos = p;
}

/**
   Wrapper for the error function, which sets the error string to "ec 'ea'".
*/
static void error_arg( int ec, const wchar_t *es, const wchar_t *ea, int p )
{
	wchar_t *msg = wcsdupcat2( es, L" \'", ea, L"\'", 0 );
	error( ec, msg, p );
	free(msg);
}

wchar_t *get_filename( const wchar_t *cmd )
{
	wchar_t *path;

	if(wcschr( cmd, '/' ) != 0 )
	{
		if( waccess( cmd, X_OK )==0 )
		{
			struct stat buff;
			wstat( cmd, &buff );
			if( S_ISREG(buff.st_mode) )
				return wcsdup( cmd );
			else
				return 0;
		}
	}
	else
	{
		path = env_get(L"PATH");
		if( path != 0 )
		{
			/*
			  Allocate string long enough to hold the whole command
			*/
			wchar_t *new_cmd = malloc( sizeof(wchar_t)*(wcslen(cmd)+wcslen(path)+2) );
			/* 
			   We tokenize a copy of the path, since strtok modifies
			   its arguments 
			*/
			wchar_t *path_cpy = wcsdup( path );
			wchar_t *nxt_path = path;
			wchar_t *state;

			if( (new_cmd==0) || (path_cpy==0) )
			{
				die_mem();
				
			}

			for( nxt_path = wcstok( path_cpy, ARRAY_SEP_STR, &state );
				 nxt_path != 0;
				 nxt_path = wcstok( 0, ARRAY_SEP_STR, &state) )
			{
				int path_len = wcslen( nxt_path );
				wcscpy( new_cmd, nxt_path );
				if( new_cmd[path_len-1] != '/' )
				{
					new_cmd[path_len++]='/';
				}
				wcscpy( &new_cmd[path_len], cmd );
				if( waccess( new_cmd, X_OK )==0 )
				{
					struct stat buff;
					if( wstat( new_cmd, &buff )==-1 )
					{
						if( errno != EACCES )
							wperror( L"stat" );
						continue;
					}
					if( S_ISREG(buff.st_mode) )
					{
						free( path_cpy );
						return new_cmd;
					}
				}
				else
				{
					switch( errno )
					{
						case ENOENT:
						case ENAMETOOLONG:
						case EACCES:
						case ENOTDIR:
							break;
						default:
							debug( 1,
								   L"Error while searching for command %d",
								   new_cmd );
							wperror( L"access" );
					}
				}
			}
			free( path_cpy );
			free( new_cmd );
		}
	}

	return 0;
}

void parser_init()
{
	if( profile )
	{
		al_init( &profile_data);
	}
	al_init( &forbidden_function );
}

void print_profile( array_list_t *p, 
					int pos, 
					FILE *out )
{
	profile_element_t *me, *prev;
	int i;		
	int my_time;
	
	if( pos >= al_get_count( p ) )
		return;
	
	me= (profile_element_t *)al_get( p, pos );
	if( !me->skipped )
	{
		my_time=me->parse+me->exec;
		
		for( i=pos+1; i<al_get_count(p); i++ )
		{
			prev = (profile_element_t *)al_get( p, i );
			if( prev->skipped )
				continue;
			
			if( prev->level <= me->level )
				break;
			if( prev->level > me->level+1 )
				continue;
			my_time -= prev->parse;
			my_time -= prev->exec;
		}
		
		if( me->cmd )
		{
			fwprintf( out, L"%d\t%d\t", my_time, me->parse+me->exec );
			for( i=0; i<me->level; i++ )
			{
				fwprintf( out, L"-" );
			}
			fwprintf( out, L"> %ls\n", me->cmd );
		}
	}
	print_profile( p, pos+1, out );	
	free( me->cmd );	
	free( me );	
}

void parser_destroy()
{
	if( profile )
	{
		/*
		  Save profiling information
		*/
		FILE *f = fopen( profile, "w" );
		if( !f )
		{
			debug( 1,
				   L"Could not write profiling information to file '%s'",
				   profile );
		}
		else
		{
			fwprintf( f, 
					  L"Time\tSum\tCommand\n",
					  al_get_count( &profile_data ) );
			print_profile( &profile_data, 0, f );
			fclose( f );
		}
		al_destroy( &profile_data );
	}
	
	al_destroy( &forbidden_function );
}

static void print_errors()
{
	if( error_code )
	{
		int tmp;

		
		debug( 0, L"%ls", err_str );

		tmp = current_tokenizer_pos;
		current_tokenizer_pos = err_pos;

		fwprintf( stderr, L"%ls", parser_current_line() );
		
		current_tokenizer_pos=tmp;
	}
}

int eval_args( const wchar_t *line, array_list_t *args )
{
	tokenizer tok;
	/*
	  eval_args may be called while evaulating another command, so we
	  save the previous tokenizer and restore it on exit
	*/
	tokenizer *previous_tokenizer=current_tokenizer; 
	int previous_pos=current_tokenizer_pos;
	int do_loop=1;
	tok_init( &tok, line, 0 );

	current_tokenizer=&tok;

	error_code=0;

	for(;do_loop && tok_has_next( &tok) ; tok_next( &tok ) )
	{
		current_tokenizer_pos = tok_get_pos( &tok );
		switch(tok_last_type( &tok ) )
		{
			case TOK_STRING:
				if( !expand_string( wcsdup(tok_last( &tok )), args, 0 ) )
				{
					err_pos=tok_get_pos( &tok );
					do_loop=0;
				}

				break;
			case TOK_END:
				break;

			case TOK_ERROR:
			{
				error_arg( SYNTAX_ERROR,
						   TOK_ERR_MSG,
						   tok_last(&tok),
						   tok_get_pos( &tok ) );

				do_loop=0;
				break;
			}

			default:
				error_arg( SYNTAX_ERROR,
						   L"Unexpected token of type",
						   tok_get_desc( tok_last_type(&tok)),
						   tok_get_pos( &tok ) );
				do_loop=0;
				break;

		}
	}

	print_errors();
	tok_destroy( &tok );

	current_tokenizer=previous_tokenizer;
	current_tokenizer_pos = previous_pos;

	return 1;
}

wchar_t *parser_current_line()
{
	int lineno=1;

	wchar_t *file = reader_current_filename();
	wchar_t *whole_str = tok_string( current_tokenizer );
	wchar_t *line = whole_str;
	wchar_t *line_end;
	int i;
	int offset;
	int current_line_pos=current_tokenizer_pos;

	if( !line )
		return L"";
	
	lineinfo[0]=0;

	/*
	  Calculate line number, line offset, etc.
	*/
	for( i=0; i<current_tokenizer_pos; i++ )
	{
		if( whole_str[i] == L'\n' )
		{
			lineno++;
			current_line_pos = current_tokenizer_pos-i-1;
			line = &whole_str[i+1];
		}
	}

	/*
	  Copy current line from whole string
	*/
	line_end = wcschr( line, L'\n' );
	if( !line_end )
		line_end = line+wcslen(line);

	line = wcsndup( line, line_end-line );

//	debug( 2, L"Current pos %d, line pos %d, file_length %d\n", current_tokenizer_pos,  current_line_pos, wcslen(whole_str));

	if( !is_interactive )
	{
		swprintf( lineinfo,
				  LINEINFO_SIZE,
				  L"%ls (line %d): %n",
				  file,
				  lineno,
				  &offset );
	}
	else
	{
		offset=0;
	}

	/* Skip printing if we are in interactive mode and the error was on the first character of the line */
	if( offset+current_line_pos )
		swprintf( lineinfo+offset,
				  LINEINFO_SIZE-offset,
				  L"%ls\n%*c^\n",
				  line,
				  offset+current_line_pos,
				  L' ' );

	free( line );

	return lineinfo;
}

int parser_get_pos()
{
	return tok_get_pos( current_tokenizer );
}

int parser_get_job_pos()
{
	return job_start_pos;
}


void parser_set_pos( int p)
{
	tok_set_pos( current_tokenizer, p );
}

const wchar_t *parser_get_buffer()
{
	return tok_string( current_tokenizer );
}


int parser_is_help( wchar_t *s, int min_match )
{
	int len = wcslen(s);

	return ( wcscmp( L"-h", s ) == 0 ) ||
		( len >= 3 && (wcsncmp( L"--help", s, len ) == 0) );
}

/**
   Parse options for the specified job

   \param p the process to parse options for
   \param j the job to which the process belongs to
   \param tok the tokenizer to read options from
   \param args the argument list to insert options into
*/
static void parse_job_main_loop( process_t *p,
								 job_t *j,
								 tokenizer *tok,
								 array_list_t *args )
{
	int is_finished=0;

	int proc_is_count=0;

	/*
	  Test if this is the 'count' command. We need to special case
	  count, since it should display a help message on 'count .h',
	  but not on 'set foo -h; count $foo'.
	*/
	if( p->actual_cmd )
	{
		wchar_t *woot = wcsrchr( p->actual_cmd, L'/' );
		if( !woot )
			woot = p->actual_cmd;
		else
			woot++;
		proc_is_count = wcscmp( woot, L"count" )==0;
	}
	
	while( 1 )
	{
		
		/* debug( 2, L"Read token %ls\n", wcsdup(tok_last( tok )) ); */
		
		switch( tok_last_type( tok ) )
		{
			case TOK_PIPE:
				if( (p->type == INTERNAL_EXEC) )
				{
					error( SYNTAX_ERROR,
						   EXEC_ERR_MSG,
						   tok_get_pos( tok ) );
					return;					
				}

				p->argv = list_to_char_arr( args );
				p->next = calloc( 1, sizeof( process_t ) );
				if( p->next == 0 )
				{
					die_mem();
					
				}
				tok_next( tok );
				if( !parse_job( p->next, j, tok ))
				{
					/*
					  Do not free args content on error - it is
					  already in p->argv and will be freed by job_free
					  later on.
					*/
					al_truncate( args, 0 );
				}
				is_finished = 1;
				break;

			case TOK_BACKGROUND:
				j->fg = 0;
			case TOK_END:
			{
				p->argv = list_to_char_arr( args );
				if( tok_has_next(tok))
					tok_next(tok);
				
				is_finished = 1;
				
				break;
			}

			case TOK_STRING:
			{
				int skip=0;

				if( current_block->skip )
				{
					skip=1;
					if( (current_block->type == SWITCH) &&
						(wcscmp( al_get( args, 0), L"case" )==0) &&
						p->type )
					{
						skip=0;
					}

				}
				
				if( !skip )
				{
					if( proc_is_count &&
						(al_get_count( args) == 1) &&
						( parser_is_help( tok_last(tok), 0) ) )
					{
						/*
						  Display help for count
						*/
						p->type = INTERNAL_BUILTIN;
						wcscpy( p->actual_cmd, L"count" );
					}

					if( !expand_string( wcsdup(tok_last( tok )),
										args,
										0 )
						)
					{
						err_pos=tok_get_pos( tok );
						if( error_code == 0 )
						{
							error_arg( SYNTAX_ERROR,
									   L"Could not expand string",
									   tok_last(tok),
									   tok_get_pos( tok ) );
						}

					}
				}

				break;
			}

			case TOK_REDIRECT_OUT:
			case TOK_REDIRECT_IN:
			case TOK_REDIRECT_APPEND:
			case TOK_REDIRECT_FD:
			{
				int type = tok_last_type( tok );
				io_data_t *new_io;
				wchar_t *target = 0;
				


				/*
				  Don't check redirections in skipped part

				  Otherwise, bogus errors may be the result
				*/
				if( current_block->skip )
				{
					tok_next( tok );
					break;
				}
				
				new_io = calloc( 1, sizeof(io_data_t) );
				if( !new_io )
					die_mem();
				
				new_io->fd = wcstol( tok_last( tok ),
									 0,
									 10 );
				tok_next( tok );

				switch( tok_last_type( tok ) )
				{
					case TOK_STRING:
					{
						target = expand_one( wcsdup( tok_last( tok ) ), 0);
						if( target == 0 && error_code == 0 )
						{
							error_arg( SYNTAX_ERROR,
									   L"Could not expand string",
									   tok_last( tok ),
									   tok_get_pos( tok ) );
							
						}
					}
					break;
					default:
						error_arg( SYNTAX_ERROR,
								   L"Expected redirection, got token of type",
								   tok_get_desc( tok_last_type(tok)),
								   tok_get_pos( tok ) );
				}
				
				if( target == 0 || wcslen( target )==0 )
				{
					if( error_code == 0 )
						error( SYNTAX_ERROR,
							   L"Invalid IO redirection",
							   tok_get_pos( tok ) );
					tok_next(tok);
				}
				else
				{
					

					switch( type )
					{
						case TOK_REDIRECT_APPEND:
							new_io->io_mode = IO_FILE;
							new_io->flags = O_CREAT | O_APPEND | O_WRONLY;
							new_io->filename = target;
							break;

						case TOK_REDIRECT_OUT:
							new_io->io_mode = IO_FILE;
							new_io->flags = O_CREAT | O_WRONLY | O_TRUNC;
							new_io->filename = target;
							break;

						case TOK_REDIRECT_IN:
							new_io->io_mode = IO_FILE;
							new_io->flags = O_RDONLY;
							new_io->filename = target;
							break;

						case TOK_REDIRECT_FD:
							if( wcscmp( target, L"-" ) == 0 )
							{
								new_io->io_mode = IO_CLOSE;
							}
							else
							{
								new_io->io_mode = IO_FD;
								new_io->old_fd = wcstol( target,
														 0,
														 10 );
								if( ( new_io->old_fd < 0 ) ||
									( new_io->old_fd > 10 ) )
								{
									error_arg( SYNTAX_ERROR,
											   L"Requested redirection to something "
											   L"that is not a file descriptor",
											   target,
											   tok_get_pos( tok ) );
									tok_next(tok);
								}
								free(target);
							}
							break;
					}
				}
				
				j->io = io_add( j->io, new_io );

			}
			break;

			case TOK_ERROR:
			{				
				error_arg( SYNTAX_ERROR,
						   TOK_ERR_MSG,
						   tok_last(tok),
						   tok_get_pos( tok ) );

				return;
			}

			default:
				error_arg( SYNTAX_ERROR,
						   L"Unexpected token of type",
						   tok_get_desc( tok_last_type(tok)),
						   tok_get_pos( tok ) );
				tok_next(tok);
				break;
		}

		if( (is_finished) || (error_code != 0) )
			break;
		
		tok_next( tok );
	}
	return;
}


/**
   Fully parse a single job. Does not call exec on it.

   \param p The process structure that should be used to represent the first process in the job.
   \param j The job structure to contain the parsed job
   \param tok tokenizer to read from

   \return 1 on success, 0 on error
*/
static int parse_job( process_t *p,
					  job_t *j,
					  tokenizer *tok )
{
	array_list_t args;      // The list that will become the argc array for the program
	int use_function = 1;   // May functions be considered when checking what action this command represents
	int use_builtin = 1;    // May builtins be considered when checking what action this command represents
	int is_new_block=0;     // Does this command create a new block? 

	block_t *prev_block = current_block;   
		
//	debug( 2, L"begin parse_job()\n" );
	al_init( &args );

	current_tokenizer_pos = tok_get_pos( tok );

	while( al_get_count( &args ) == 0 )
	{
		wchar_t *nxt=0;
		switch( tok_last_type( tok ))
		{
			case TOK_STRING:
				nxt = expand_one( wcsdup(tok_last( tok )),
								  EXPAND_SKIP_SUBSHELL | EXPAND_SKIP_VARIABLES);
				if( nxt == 0 )
				{
					error_arg( SYNTAX_ERROR,
							   L"Illegal command name ",
							   tok_last( tok ),
							   tok_get_pos( tok ) );
					al_destroy( &args );
					return 0;
				}
				break;

			case TOK_ERROR:
			{
				error_arg( SYNTAX_ERROR,
						   TOK_ERR_MSG,
						   tok_last(tok),
						   tok_get_pos( tok ) );
				
				al_destroy( &args );
				return 0;
			}

			default:
				error_arg( SYNTAX_ERROR,
						   L"Expected a command name, got token of type ",
						   tok_get_desc( tok_last_type(tok)),
						   tok_get_pos( tok ) );
				al_destroy( &args );
				return 0;
		}

		int mark = tok_get_pos( tok );

		if( wcscmp( L"command", nxt )==0 )
		{
			tok_next( tok );
			if( parser_is_help( tok_last( tok ), 0 ) )
			{
				tok_set_pos( tok, mark);
			}
			else
			{
				use_function = 0;
				use_builtin=0;
				free( nxt );
				continue;
			}
		}
		else if(  wcscmp( L"builtin", nxt )==0 )
		{
			tok_next( tok );
			if( tok_last(tok)[0] == L'-' )
			{
				tok_set_pos( tok, mark);
			}
			else
			{
				use_function = 0;
				free( nxt );
				continue;
			}
		}
		else if(  wcscmp( L"not", nxt )==0 )
		{
			tok_next( tok );
			if( tok_last(tok)[0] == L'-' )
			{
				tok_set_pos( tok, mark);
			}
			else
			{
				j->negate=1-j->negate;
				free( nxt );
				continue;
			}
		}
		else if(  wcscmp( L"and", nxt )==0 )
		{
			tok_next( tok );
			if( tok_last(tok)[0] == L'-' )
			{
				tok_set_pos( tok, mark);
			}
			else
			{
				parser_push_block( AND );
				free( nxt );
				continue;
			}
		}
		else if(  wcscmp( L"or", nxt )==0 )
		{
			tok_next( tok );
			if( tok_last(tok)[0] == L'-' )
			{
				tok_set_pos( tok, mark);
			}
			else
			{
				parser_push_block( OR );
				free( nxt );
				continue;
			}
		}
		else if(  wcscmp( L"exec", nxt )==0 )
		{
			if( p != j->first_process )
			{
				error( SYNTAX_ERROR,
					   EXEC_ERR_MSG,
					   tok_get_pos( tok ) );
				al_destroy( &args );
				free(nxt);				
				return 0;
			}
			
			tok_next( tok );
			if( tok_last(tok)[0] == L'-' )
			{
				tok_set_pos( tok, mark);
			}
			else
			{
				use_function = 0;
				use_builtin=0;
				p->type=INTERNAL_EXEC;				
				free( nxt );
				continue;
			}
		}
		else if( wcscmp( L"while", nxt ) ==0 )
		{
			int new_block = 0;
			tok_next( tok );

			if( (current_block->type != WHILE) )
			{
				new_block = 1;
			}
			else if( current_block->while_state == WHILE_TEST_AGAIN )
			{
				current_block->while_state = WHILE_TEST_FIRST;
			}
			else
			{
				new_block = 1;
			}
			
			if( new_block )
			{
				parser_push_block( WHILE );
				current_block->while_state=WHILE_TEST_FIRST;
				current_block->tok_pos = mark;
			}
			
			free( nxt );
			is_new_block=1;
			
			continue;
		}
		else if( wcscmp( L"if", nxt ) ==0 )
		{
			tok_next( tok );

			parser_push_block( IF );

			current_block->if_state=0;
			current_block->tok_pos = mark;

			free( nxt );
			is_new_block=1;
			continue;
		}

		if( use_function)
		{
			int nxt_forbidden;
			wchar_t *forbid;

			forbid = (wchar_t *)(al_get_count( &forbidden_function)?al_peek( &forbidden_function ):0);
			nxt_forbidden = forbid && (wcscmp( forbid, nxt) == 0 );

			/*
			  Make feeble attempt to avoid infinite recursion. Will at
			  least catch some accidental infinite recursion calls.
			*/
			if( function_exists( nxt ) && !nxt_forbidden)
			{
				/*
				  Check if we have reached the maximum recursion depth
				*/
				if( al_get_count( &forbidden_function ) > MAX_RECURSION_DEPTH )
				{
					error( SYNTAX_ERROR,
						   RECURSION_ERR_MSG,
						   tok_get_pos( tok ) );
				}
				else
				{
					p->type = INTERNAL_FUNCTION;
				}
			}
		}
		al_push( &args, nxt );
	}

	if( error_code == 0 )
	{
		if( !p->type )
		{
			if( use_builtin &&
				builtin_exists( (wchar_t *)al_get( &args, 0 ) ) )
			{
				p->type = INTERNAL_BUILTIN;
				is_new_block = parser_is_block( (wchar_t *)al_get( &args, 0 ) );
			}			
		}

		if( !p->type || (p->type == INTERNAL_EXEC) )
		{
			/* 
			   If we are not executing the current block, allow
			   non-existent commands.
			*/
			if( current_block->skip )
			{
				p->actual_cmd = wcsdup(L"");
			}
			else
			{
				
				p->actual_cmd = get_filename( (wchar_t *)al_get( &args, 0 ) );
				/*
				  Check if the specified command exists
				*/
				if( p->actual_cmd == 0 )
				{
					
					/*
					  That is not a command! Test if it is a
					  directory, in which case, we use 'cd' as the
					  implicit command.
					*/
					wchar_t *pp =
						parser_cdpath_get( (wchar_t *)al_get( &args, 0 ) );
					if( pp )
					{
						wchar_t *tmp;
						free( pp );
						
						tmp = (wchar_t *)al_get( &args, 0 );
						al_truncate( &args, 0 );
						al_push( &args, wcsdup( L"cd" ) );
						al_push( &args, tmp );
						/*
						  If we have defined a wrapper around cd, use it, 
						  otherwise use the cd builtin
						*/
						if( function_exists( L"cd" ) )
							p->type = INTERNAL_FUNCTION;
						else
							p->type = INTERNAL_BUILTIN;
					}
					else
					{
						error_arg( EVAL_ERROR,
								   L"Unknown command",
								   (wchar_t *)al_get( &args, 0 ),
								   tok_get_pos( tok ) );
					}
				}
			}
		}
	}

	if( is_new_block )
	{
		const wchar_t *end=parser_find_end( tok_string( tok ) + 
											current_tokenizer_pos );
		tokenizer subtok;
		int make_sub_block = j->first_process != p;
	
		if( !end )
		{
			error( SYNTAX_ERROR,
				   L"Could not find end of block" ,
				   tok_get_pos( tok ) );
		}

		if( !make_sub_block )
		{
			tok_init( &subtok, end, 0 );
			switch( tok_last_type( &subtok ) )
			{
				case TOK_END:
					break;
					
				case TOK_REDIRECT_OUT:
				case TOK_REDIRECT_APPEND:
				case TOK_REDIRECT_IN:
				case TOK_REDIRECT_FD:
				case TOK_PIPE:
				{
					make_sub_block = 1;
					break;					
				}
				
				default:
				{
					error_arg( SYNTAX_ERROR,
							   L"Expected end of command, got token of type ",
							   tok_get_desc( tok_last_type(tok)),
							   tok_get_pos( tok ) );
				}
			}
			tok_destroy( &subtok );
		}
		
		if( make_sub_block )
		{

			int end_pos = end-tok_string( tok );
			wchar_t *sub_block= wcsndup( tok_string( tok ) + current_tokenizer_pos, 
										 end_pos - current_tokenizer_pos);
			
			p->type = INTERNAL_BLOCK;
			free( (void *)al_get( &args, 0 ) );
			al_set( &args, 0, sub_block );

			tok_set_pos( tok, 
						 end_pos );

			while( prev_block != current_block )
				parser_pop_block();
		}
		else tok_next( tok );
		
	}
	else tok_next( tok );
	
	if( !error_code )
		parse_job_main_loop( p, j, tok, &args );

	if( error_code )
	{
		/*
		  We don't know what the state of the args array and the argv
		  vector is on error, so we do an internal cleanup here.
		*/
		al_foreach( &args,
					(void (*)(const void *))&free );
		free(p->argv);		
		p->argv=0;		
		/*
		  Make sure the block stack is consistent
		*/
		while( prev_block != current_block )
			parser_pop_block();

	}
	al_destroy( &args );
	
//	debug( 2, L"end parse_job()\n" );
	return !error_code;
}

/**
   Do skipped execution of command. This means that only limited
   execution of block level commands such as end and switch should be
   preformed.

   \param j the job to execute
   
*/
static void skipped_exec( job_t * j )
{
	process_t *p;
	for( p = j->first_process; p; p=p->next )
	{
		if( p->type )
		{
			if(( wcscmp( p->argv[0], L"for" )==0) ||
			   ( wcscmp( p->argv[0], L"switch" )==0) ||
			   ( wcscmp( p->argv[0], L"function" )==0))
			{
				parser_push_block( FAKE );
			}
			else if( wcscmp( p->argv[0], L"end" )==0)
			{
				if(!current_block->outer->skip )
				{
					exec( j );
					return;
				}
				parser_pop_block();
			}
			else if( wcscmp( p->argv[0], L"else" )==0)
			{
				if( (current_block->type == IF ) &&
					(current_block->if_state != 0))
				{
					exec( j );
					return;
				}
			}
			else if( wcscmp( p->argv[0], L"case" )==0)
			{
				if( (current_block->type == SWITCH ) )
				{
					exec( j );
					return;
				}
			}
		}
	}
	job_free( j );
}

/**
   Evaluates a job from the specified tokenizer. First calls
   parse_job to parse the job and then calls exec to execute it.

   \param tok The tokenizer to read tokens from
*/
					
static void eval_job( tokenizer *tok )
{
	job_t *j;

	int start_pos = job_start_pos = tok_get_pos( tok );
	debug( 2, L"begin eval_job()\n" );
	long long t1=0, t2=0, t3=0;
	profile_element_t *p=0;
	int skip = 0;

	if( !is_block && !is_subshell )
		env_universal_read_all();

	if( profile )
	{
		p=malloc( sizeof(profile_element_t));
		p->cmd=0;		
		al_push( &profile_data, p );
		p->skipped=1;
		t1 = get_time();
	}
	
	switch( tok_last_type( tok ) )
	{
		case TOK_STRING:
		{
			j = job_create();
			j->command=0;
			j->fg=1;
			j->constructed=0;
			j->skip_notification = is_subshell;
			
			if( is_interactive )
			{
				if( tcgetattr (0, &j->tmodes) )
				{
					tok_next( tok );
					wperror( L"tcgetattr" );
					job_free( j );
					break;
				}
			}

			j->first_process = calloc( 1, sizeof( process_t ) );

			/* Copy the command name */
			if( current_block->type == OR )
			{
				skip = (proc_get_last_status() == 0 );
				parser_pop_block();
			}
			else if( current_block->type == AND )
			{
				skip = (proc_get_last_status() != 0 );
				parser_pop_block();
			}
			

			if( parse_job( j->first_process, j, tok ) &&
				j->first_process->argv )
			{
				if( job_start_pos < tok_get_pos( tok ) )
				{
					int stop_pos = tok_get_pos( tok );
					wchar_t *newline = wcschr(  tok_string(tok)+start_pos, 
												L'\n' );
					if( newline )
						stop_pos = mini( stop_pos, newline - tok_string(tok) );
					
					j->command = wcsndup( tok_string(tok)+start_pos,
										  stop_pos-start_pos );
				}
				else
					j->command = wcsdup( L"" );
				
				if( profile )
				{
					t2 = get_time();
					p->cmd = wcsdup( j->command );					
					p->skipped=current_block->skip;
				}

				skip |= current_block->skip;
				
				if(!skip )
				{
					exec( j );					
				}
				else
				{
					skipped_exec( j );					
				}
				
				if( profile )
				{
					t3 = get_time();
					p->level=eval_level;
					p->parse = t2-t1;
					p->exec=t3-t2;
				}

				if( current_block->type == WHILE )
				{
//					debug( 2, L"We are at begining of a while block\n" );
					
					switch( current_block->while_state )
					{
						case WHILE_TEST_FIRST:
						{
							current_block->skip = proc_get_last_status()!= 0;
							current_block->while_state=WHILE_TESTED;
						}
						break;
					}
				}

				if( current_block->type == IF )
				{
					if( (!current_block->if_state) &&
						(!current_block->skip) )
					{
						/*
						  We need to call job_do_notification,
						  since this is the function which sets
						  the status of the last process to exit
						*/
//							debug( 2, L"Result of if block is %d\n", proc_get_last_status() );

						current_block->skip = proc_get_last_status()!= 0;
						current_block->if_state++;
					}
				}
				
			}
			else
			{
				job_free( j );
			}
			break;
		}
		
		case TOK_END:
		{
			if( tok_has_next( tok ))
				tok_next( tok );
			break;
		}

		case TOK_ERROR:
		{
			error_arg( SYNTAX_ERROR,
					   TOK_ERR_MSG,
					   tok_last(tok),
					   tok_get_pos( tok ) );

			return;
		}

		default:
		{
			error_arg( SYNTAX_ERROR,
					   L"Expected a command string, got token of type",
					   tok_get_desc( tok_last_type(tok)),
					   tok_get_pos( tok ) );

			return;
		}
	}
	
	if( is_subshell )
		job_do_notification();
//	debug( 2, L"end eval_job()\n" );
}

int eval( const wchar_t *cmd, io_data_t *io, int block_type )
{
	int forbid_count;
	int code;
	tokenizer *previous_tokenizer=current_tokenizer;
	block_t *start_current_block = current_block;
	io_data_t *prev_io = block_io;
	block_io = io;

	debug( 2, L"Eval command %ls", cmd );

	if( !cmd )
	{
		debug( 1,
			   L"Tried to evaluate null pointer\n"
			   L"If this error can be reproduced, please file a bug report." );		
		return 1;
	}

	if( (block_type!=TOP) && 
		(block_type != FUNCTION_CALL) &&
		(block_type != SUBST))
	{
		debug( 1,
			   L"Tried to evaluate buffer using invalid block scope of type '%ls'\n"
			   L"If this error can be reproduced, please file a bug report.", 
			   parser_get_block_desc( block_type ) );
        return 1;
    }
	
	
	eval_level++;
	current_tokenizer = malloc( sizeof(tokenizer));

	parser_push_block( block_type );

	forbid_count = al_get_count( &forbidden_function );

	tok_init( current_tokenizer, cmd, 0 );
	error_code = 0;

	while( tok_has_next( current_tokenizer ) &&
		   !error_code &&
		   !sanity_check() &&
		   !exit_status() )
		eval_job( current_tokenizer );

	int prev_block_type = current_block->type;	
	parser_pop_block();

	while( start_current_block != current_block )
	{
		if( current_block == 0 )
		{
			debug( 0,
				   L"End of block mismatch\n"
				   L"Program terminating. If this error can be reproduced,\n"
				   L"please file a bug report." );
			exit(1);
			break;
		}

		if( (!error_code) && (!exit_status()) && (!proc_get_last_status()) )
		{
			char *h;

			//debug( 2, L"Status %d\n", proc_get_last_status() );

			switch( prev_block_type )
			{
				case OR:
				case AND:
					debug( 1, 
						   COND_ERR_MSG );					
					fwprintf( stderr, L"%ls", parser_current_line() );
					
					h = builtin_help_get( prev_block_type == OR? L"or": L"and" );
					if( h )
						fwprintf( stderr, L"%s", h );
					break;
					
				default:
					debug( 1, 
						   L"%ls", parser_get_block_desc( current_block->type ) );
					debug( 1, 
						   END_ERR_MSG );
					fwprintf( stderr, L"%ls", parser_current_line() );
			
					h = builtin_help_get( L"end" );
					if( h )
						fwprintf( stderr, L"%s", h );
					break;
			}
			
		}
		prev_block_type = current_block->type;	
		parser_pop_block();
	}

	print_errors();

	tok_destroy( current_tokenizer );
	free( current_tokenizer );

	while( forbid_count < al_get_count( &forbidden_function ))
		parser_allow_function();

	current_tokenizer=previous_tokenizer;

	code=error_code;
	error_code=0;

	block_io = prev_io;	

	eval_level--;

	return code;
}


int parser_test( wchar_t * buff,
				 int babble )
{
	tokenizer tok;
	int had_cmd=0;
	int count = 0;
	int err=0;
	tokenizer *previous_tokenizer=current_tokenizer;
	int previous_pos=current_tokenizer_pos;
	static int block_pos[BLOCK_MAX_COUNT];
	static int block_type[BLOCK_MAX_COUNT];
	int is_pipeline = 0;
	int forbid_pipeline = 0;
	int needs_cmd=0;
	int require_additional_commands=0;
		
	current_tokenizer = &tok;

	for( tok_init( &tok, buff, 0 );
		 tok_has_next( &tok ) && !err;
		 tok_next( &tok ) )
	{
		current_tokenizer_pos = tok_get_pos( &tok );

		int last_type = tok_last_type( &tok );
		switch( last_type )
		{
			case TOK_STRING:
			{
				if( !had_cmd )
				{
					int mark = tok_get_pos( &tok );
					had_cmd = 1;
					
					if( require_additional_commands )
					{
						if( contains_str( tok_last(&tok),
										  L"end",
										  0 ) )
						{
							err=1;
							if( babble )
							{					
								error( SYNTAX_ERROR,
									   COND_ERR_MSG,
									   tok_get_pos( &tok ) );
								print_errors();									
							}
						}
													
						require_additional_commands--;
					}

					if( wcscmp(tok_last(&tok), L"end")==0)
					{
						tok_next( &tok );
						count--;
						tok_set_pos( &tok, mark );
					}
					else if( parser_is_block( tok_last(&tok) ) )
					{
						if( count >= BLOCK_MAX_COUNT )
						{
							error( SYNTAX_ERROR, BLOCK_ERR_MSG, tok_get_pos( &tok ) );
							print_errors();
						}
						else
						{
							if( wcscmp( tok_last(&tok), L"while") == 0 )
								block_type[count] = WHILE;
							else if( wcscmp( tok_last(&tok), L"for") == 0 )
								block_type[count] = FOR;
							else if( wcscmp( tok_last(&tok), L"switch") == 0 )
								block_type[count] = SWITCH;
							else if( wcscmp( tok_last(&tok), L"if") == 0 )
								block_type[count] = IF;
							else if( wcscmp( tok_last(&tok), L"function") == 0 )
								block_type[count] = FUNCTION_DEF;
							else 
								block_type[count] = -1;							
							
//							debug( 2, L"add block of type %d after cmd %ls\n", block_type[count], tok_last(&tok) );
							

							block_pos[count] = current_tokenizer_pos;
							tok_next( &tok );
							count++;
							tok_set_pos( &tok, mark );
						}
					}

					if( parser_is_subcommand( tok_last( &tok ) ) )
					{
						needs_cmd = 1;
						had_cmd = 0;
					}

					if( contains_str( tok_last( &tok ),
									  L"or",
									  L"and",
									  0 ) )
					{
						if( is_pipeline )
						{
							err=1;
							if( babble )
							{									
								error( SYNTAX_ERROR,
									   EXEC_ERR_MSG,
									   tok_get_pos( &tok ) );
								print_errors();									
								
							}
						}
						require_additional_commands=2;
					}
					

					if( parser_is_pipe_forbidden( tok_last( &tok ) ) )
					{
						if( is_pipeline )
						{
							err=1;
							if( babble )
							{									
								error( SYNTAX_ERROR,
									   EXEC_ERR_MSG,
									   tok_get_pos( &tok ) );
								print_errors();									
								
							}
						}
						forbid_pipeline = 1;							
					}
					
					if( wcscmp( L"case", tok_last( &tok ) )==0 )
					{
						if( !count || block_type[count-1]!=SWITCH )
						{
							err=1;
							
//							debug( 2, L"Error on block type %d\n", block_type[count-1] );
							

                            if( babble )
                            {
                                error( SYNTAX_ERROR,
                                       L"'case' builtin not inside of switch block",
                                       tok_get_pos( &tok ) );
                                print_errors();
                            }
                        }
					}					
					else if( wcscmp( L"break", tok_last( &tok ) )==0 || 
							 wcscmp( L"continue", tok_last( &tok ) )==0)
					{
						int found_loop=0;
						int i;
						for( i=count-1; i>=0; i-- )
						{
							if( (block_type[i]==WHILE) ||
								(block_type[i]==FOR) )
							{
								found_loop=1;
								break;
							}
						}
							
						if( !found_loop )
						{
							err=1;
							
                            if( babble )
                            {
                                error( SYNTAX_ERROR,
                                       L"Loop control command while not inside of loop",
                                       tok_get_pos( &tok ) );
                                print_errors();
                            }
                        }						
					}
					else if( wcscmp( L"else", tok_last( &tok ) )==0 )
					{
						if( !count || block_type[count-1]!=IF )
                        {
                            err=1;
                            if( babble )
                            {
                                error( SYNTAX_ERROR,
                                       L"'else' builtin not inside of if block",
                                       tok_get_pos( &tok ) );
                                print_errors();
                            }
                        }

					}
					
					if( count < 0 )
					{
						err = 1;
						if( babble )
						{
							error( SYNTAX_ERROR,
								   L"'end' command outside of block",
								   tok_get_pos( &tok ) );
							print_errors();
						}						
					}
				}
				break;
			}

			case TOK_REDIRECT_OUT:
			case TOK_REDIRECT_IN:
			case TOK_REDIRECT_APPEND:
			case TOK_REDIRECT_FD:
			{
				if( !had_cmd )
				{
					err = 1;
					if( babble )
					{
						error( SYNTAX_ERROR,
							   L"Redirection error",
							   tok_get_pos( &tok ) );
						print_errors();
					}
				}
				break;
			}

			case TOK_END:
			{
				if( needs_cmd && !had_cmd )
				{
					err = 1;					
                    if( babble )
                    {
                        error( SYNTAX_ERROR,
							   CMD_ERR_MSG,
                               tok_get_pos( &tok ) );
                        print_errors();
                    }
				}				
				needs_cmd=0;				
				had_cmd = 0;
				is_pipeline=0;				
				forbid_pipeline=0;
				break;
			}

			case TOK_PIPE:
			{
				if( forbid_pipeline )
				{
					err=1;
					if( babble )
					{									
						error( SYNTAX_ERROR,
							   EXEC_ERR_MSG,
							   tok_get_pos( &tok ) );
						print_errors();									
					}
				}
				needs_cmd=0;				
				is_pipeline=1;
			}
		

			case TOK_BACKGROUND:
			{
				if( needs_cmd && !had_cmd )
				{
					err = 1;					
                    if( babble )
                    {
                        error( SYNTAX_ERROR,
							   CMD_ERR_MSG,
                               tok_get_pos( &tok ) );
                        print_errors();
                    }
				}		
		
				if( had_cmd )
				{
					had_cmd = 0;
				}
				break;
			}

			case TOK_ERROR:
			default:
				err = 1;
				if( babble )
				{
					error_arg( SYNTAX_ERROR,
							   TOK_ERR_MSG,
							   tok_last(&tok),
							   tok_get_pos( &tok ) );
					print_errors();
					//debug( 2, tok_last( &tok) );
				}
				break;
		}
	}
	
	if( require_additional_commands )
	{
		err=1;
		if( babble )
		{									
			error( SYNTAX_ERROR,
				   COND_ERR_MSG,
				   tok_get_pos( &tok ) );
			print_errors();									
		}
	}


	if( babble && count>0 )
	{
		error( SYNTAX_ERROR,
			   END_ERR_MSG L"\n",
			   block_pos[count-1] );
		print_errors();
	}

	tok_destroy( &tok );


	current_tokenizer=previous_tokenizer;
	current_tokenizer_pos = previous_pos;

	error_code=0;

	return err | ((count!=0)<<1);
}