/*
 * "Software pw3270, desenvolvido com base nos códigos fontes do WC3270  e X3270
 * (Paul Mattes Paul.Mattes@usa.net), de emulação de terminal 3270 para acesso a
 * aplicativos mainframe. Registro no INPI sob o nome G3270. Registro no INPI sob
 * o nome G3270.
 *
 * Copyright (C) <2008> <Banco do Brasil S.A.>
 *
 * Este programa é software livre. Você pode redistribuí-lo e/ou modificá-lo sob
 * os termos da GPL v.2 - Licença Pública Geral  GNU,  conforme  publicado  pela
 * Free Software Foundation.
 *
 * Este programa é distribuído na expectativa de  ser  útil,  mas  SEM  QUALQUER
 * GARANTIA; sem mesmo a garantia implícita de COMERCIALIZAÇÃO ou  de  ADEQUAÇÃO
 * A QUALQUER PROPÓSITO EM PARTICULAR. Consulte a Licença Pública Geral GNU para
 * obter mais detalhes.
 *
 * Você deve ter recebido uma cópia da Licença Pública Geral GNU junto com este
 * programa; se não, escreva para a Free Software Foundation, Inc., 51 Franklin
 * St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Este programa está nomeado como - e possui - linhas de código.
 *
 * Contatos:
 *
 * perry.werneck@gmail.com	(Alexandre Perry de Souza Werneck)
 * erico.mendonca@gmail.com	(Erico Mascarenhas Mendonça)
 *
 */

/**
 * @brief Utility functions.
 */

#define _GNU_SOURCE

#include <lib3270-internals.h>
#include "utilc.h"
#include "popupsc.h"
#include <lib3270/selection.h>
#include <lib3270/log.h>

#define my_isspace(c)	isspace((unsigned char)c)

/**
 * @brief Cheesy internal version of sprintf that allocates its own memory.
 */
char * lib3270_vsprintf(const char *fmt, va_list args)
{
	char *r = NULL;

#if defined(HAVE_VASPRINTF)

	if(vasprintf(&r, fmt, args) < 0 || !r)
		Error(NULL,"Out of memory in %s",__FUNCTION__);

#else

	char buf[16384];
	int nc;

	nc = vsnprintf(buf, sizeof(buf), fmt, args);
	if(nc < 0)
	{
		Error(NULL,"Out of memory in %s",__FUNCTION__);
	}
	else if (nc < sizeof(buf))
	{
		r = lib3270_malloc(nc + 1);
		strcpy(r, buf);

	}
	else
	{
		r = lib3270_malloc(nc + 1);
		if(vsnprintf(r, nc, fmt, args) < 0)
			Error(NULL,"Out of memory in %s",__FUNCTION__);

	}

#endif

	return r;
}

LIB3270_EXPORT char * lib3270_strdup_printf(const char *fmt, ...)
{
	va_list args;
	char *r;

	va_start(args, fmt);
	r = lib3270_vsprintf(fmt, args);
	va_end(args);
	return r;
}

/**
 * @brief Common helper functions to insert strings, through a template, into a new  buffer.
 *
 * @param format	A printf format string with '%s's in it.
 *
 */
char * xs_buffer(const char *fmt, ...)
{
	va_list args;
	char *r;

	va_start(args, fmt);
	r = lib3270_vsprintf(fmt, args);
	va_end(args);
	return r;
}

/* Common uses of xs_buffer. */
void
xs_warning(const char *fmt, ...)
{
	va_list args;
	char *r;

	va_start(args, fmt);
	r = lib3270_vsprintf(fmt, args);
	va_end(args);
	Warning(NULL,r);
	lib3270_free(r);
}

void
xs_error(const char *fmt, ...)
{
	va_list args;
	char *r;

	va_start(args, fmt);
	r = lib3270_vsprintf(fmt, args);
	va_end(args);
	Error(NULL,r);
	lib3270_free(r);
}


/**
 * @brief Definition resource splitter.
 *
 * Definition resource splitter, for resources of the repeating form:
 *	left: right\n
 *
 * Can be called iteratively to parse a list.
 * Returns 1 for success, 0 for EOF, -1 for error.
 *
 * Note: Modifies the input string.
 */
int
split_dresource(char **st, char **left, char **right)
{
	char *s = *st;
	char *t;
	Boolean quote;

	/* Skip leading white space. */
	while (my_isspace(*s))
		s++;

	/* If nothing left, EOF. */
	if (!*s)
		return 0;

	/* There must be a left-hand side. */
	if (*s == ':')
		return -1;

	/* Scan until an unquoted colon is found. */
	*left = s;
	for (; *s && *s != ':' && *s != '\n'; s++)
		if (*s == '\\' && *(s+1) == ':')
			s++;
	if (*s != ':')
		return -1;

	/* Stip white space before the colon. */
	for (t = s-1; my_isspace(*t); t--)
		*t = '\0';

	/* Terminate the left-hand side. */
	*(s++) = '\0';

	/* Skip white space after the colon. */
	while (*s != '\n' && my_isspace(*s))
		s++;

	/* There must be a right-hand side. */
	if (!*s || *s == '\n')
		return -1;

	/* Scan until an unquoted newline is found. */
	*right = s;
	quote = False;
	for (; *s; s++) {
		if (*s == '\\' && *(s+1) == '"')
			s++;
		else if (*s == '"')
			quote = !quote;
		else if (!quote && *s == '\n')
			break;
	}

	/* Strip white space before the newline. */
	if (*s) {
		t = s;
		*st = s+1;
	} else {
		t = s-1;
		*st = s;
	}
	while (my_isspace(*t))
		*t-- = '\0';

	/* Done. */
	return 1;
}

/**
 * @brief Split a DBCS resource into its parts.
 *
 * Returns the number of parts found:
 *	-1 error (empty sub-field)
 *	 0 nothing found
 *	 1 one and just one thing found
 *	 2 two things found
 *	 3 more than two things found
 */
int
split_dbcs_resource(const char *value, char sep, char **part1, char **part2)
{
	int n_parts = 0;
	const char *s = value;
	const char *f_start = CN;	/* start of sub-field */
	const char *f_end = CN;		/* end of sub-field */
	char c;
	char **rp;

	*part1 = CN;
	*part2 = CN;

	for( ; ; ) {
		c = *s;
		if (c == sep || c == '\0') {
			if (f_start == CN)
				return -1;
			if (f_end == CN)
				f_end = s;
			if (f_end == f_start) {
				if (c == sep) {
					if (*part1) {
						lib3270_free(*part1);
						*part1 = NULL;
					}
					if (*part2) {
						lib3270_free(*part2);
						*part2 = NULL;
					}
					return -1;
				} else
					return n_parts;
			}
			switch (n_parts) {
			case 0:
				rp = part1;
				break;
			case 1:
				rp = part2;
				break;
			default:
				return 3;
			}
			*rp = lib3270_malloc(f_end - f_start + 1);
			strncpy(*rp, f_start, f_end - f_start);
			(*rp)[f_end - f_start] = '\0';
			f_end = CN;
			f_start = CN;
			n_parts++;
			if (c == '\0')
				return n_parts;
		} else if (isspace(c)) {
			if (f_end == CN)
				f_end = s;
		} else {
			if (f_start == CN)
				f_start = s;
			f_end = CN;
		}
		s++;
	}
}

#if defined(X3270_DISPLAY) /*[*/
/**
 * @brief List resource splitter, for lists of elements speparated by newlines.
 *
 * Can be called iteratively.
 * Returns 1 for success, 0 for EOF, -1 for error.
 */
int
split_lresource(char **st, char **value)
{
	char *s = *st;
	char *t;
	Boolean quote;

	/* Skip leading white space. */
	while (my_isspace(*s))
		s++;

	/* If nothing left, EOF. */
	if (!*s)
		return 0;

	/* Save starting point. */
	*value = s;

	/* Scan until an unquoted newline is found. */
	quote = False;
	for (; *s; s++) {
		if (*s == '\\' && *(s+1) == '"')
			s++;
		else if (*s == '"')
			quote = !quote;
		else if (!quote && *s == '\n')
			break;
	}

	/* Strip white space before the newline. */
	if (*s) {
		t = s;
		*st = s+1;
	} else {
		t = s-1;
		*st = s;
	}
	while (my_isspace(*t))
		*t-- = '\0';

	/* Done. */
	return 1;
}
#endif /*]*/


/**
 *	@brief Expands a character in the manner of "cat -v".
 */
char *
ctl_see(int c)
{
	static char	buf[64];
	char	*p = buf;

	c &= 0xff;
	if ((c & 0x80) && (c <= 0xa0)) {
		*p++ = 'M';
		*p++ = '-';
		c &= 0x7f;
	}
	if (c >= ' ' && c != 0x7f) {
		*p++ = c;
	} else {
		*p++ = '^';
		if (c == 0x7f) {
			*p++ = '?';
		} else {
			*p++ = c + '@';
		}
	}
	*p = '\0';
	return buf;
}

/**
 * @brief Whitespace stripper.
 */
char *
strip_whitespace(const char *s)
{
	char *t = NewString(s);

	while (*t && my_isspace(*t))
		t++;
	if (*t) {
		char *u = t + strlen(t) - 1;

		while (my_isspace(*u)) {
			*u-- = '\0';
		}
	}
	return t;
}

/**
 * @brief Hierarchy (a>b>c) splitter.
 */
Boolean
split_hier(char *label, char **base, char ***parents)
{
	int n_parents = 0;
	char *gt;
	char *lp;

	label = NewString(label);
	for (lp = label; (gt = strchr(lp, '>')) != CN; lp = gt + 1) {
		if (gt == lp)
			return False;
		n_parents++;
	}
	if (!*lp)
		return False;

	if (n_parents) {
		*parents = (char **)Calloc(n_parents + 1, sizeof(char *));
		for (n_parents = 0, lp = label;
		     (gt = strchr(lp, '>')) != CN;
		     lp = gt + 1) {
			(*parents)[n_parents++] = lp;
			*gt = '\0';
		}
		*base = lp;
	} else {
		(*parents) = NULL;
		(*base) = label;
	}
	return True;
}

/**
 * @brief Incremental, reallocing version of snprintf.
 */
#define RPF_BLKSIZE	4096
#define SP_TMP_LEN	16384

/* Initialize an RPF structure. */
void
rpf_init(rpf_t *r)
{
	r->buf = NULL;
	r->alloc_len = 0;
	r->cur_len = 0;
}

/**
 * @brief Reset an initialized RPF structure (re-use with length 0).
 */
void
rpf_reset(rpf_t *r)
{
	r->cur_len = 0;
}

/**
 * @brief Append a string to a dynamically-allocated buffer.
 */
void
rpf(rpf_t *r, char *fmt, ...)
{
	va_list a;
	Boolean need_realloc = False;
	int ns;
	char tbuf[SP_TMP_LEN];

	/* Figure out how much space would be needed. */
	va_start(a, fmt);
	ns = vsprintf(tbuf, fmt, a); /* XXX: dangerous, but so is vsnprintf */
	va_end(a);
	if (ns >= SP_TMP_LEN)
	    Error(NULL,"rpf overrun");

	/* Make sure we have that. */
	while (r->alloc_len - r->cur_len < ns + 1) {
		r->alloc_len += RPF_BLKSIZE;
		need_realloc = True;
	}
	if (need_realloc) {
		r->buf = Realloc(r->buf, r->alloc_len);
	}

	/* Scribble onto the end of that. */
	(void) strcpy(r->buf + r->cur_len, tbuf);
	r->cur_len += ns;
}

/**
 * @brief Free resources associated with an RPF.
 */
void
rpf_free(rpf_t *r)
{
	lib3270_free(r->buf);
	r->buf = NULL;
	r->alloc_len = 0;
	r->cur_len = 0;
}

LIB3270_EXPORT void * lib3270_free(void *p)
{
	if(p)
		free(p);
	return NULL;
}

LIB3270_EXPORT void lib3270_autoptr_cleanup_char(char **ptr)
{
	if(*ptr)
		free(*ptr);
	*ptr = NULL;
}

LIB3270_EXPORT void * lib3270_realloc(void *p, int len)
{
	p = realloc(p, len);
	if(!p)
		Error(NULL,"Out of memory in %s",__FUNCTION__);
	return p;
}

LIB3270_EXPORT void * lib3270_calloc(int elsize, int nelem, void *ptr)
{
	size_t sz = nelem * elsize;

	if(ptr)
		ptr = realloc(ptr,sz);
	else
		ptr = malloc(sz);

	if(ptr)
		memset(ptr,0,sz);
	else
		Error(NULL,"Out of memory in %s",__FUNCTION__);

	return ptr;
}

LIB3270_EXPORT void * lib3270_malloc(int len)
{
	char *r;

	r = malloc(len);
	if (r == (char *)NULL)
	{
		Error(NULL,"Out of memory in %s",__FUNCTION__);
		return 0;
	}

	memset(r,0,len);
	return r;
}

LIB3270_EXPORT void * lib3270_strdup(const char *str)
{
	char *r;

	r = strdup(str);
	if (r == (char *)NULL)
	{
		Error(NULL,"Out of memory in %s",__FUNCTION__);
		return 0;
	}

	return r;
}

LIB3270_EXPORT const char * lib3270_get_version(void)
{
	return build_rpq_version;
}

LIB3270_EXPORT const char * lib3270_get_revision(void)
{
	return build_rpq_revision;
}

void lib3270_popup_an_errno(H3270 *hSession, int errn, const char *fmt, ...)
{
	va_list	  args;
	char	* text;

	va_start(args, fmt);
	text = lib3270_vsprintf(fmt, args);
	va_end(args);

	lib3270_write_log(hSession, "3270", "Error Popup:\n%s\nrc=%d (%s)",text,errn,strerror(errn));

	lib3270_popup_dialog(hSession, LIB3270_NOTIFY_ERROR, _( "Error" ), text, "%s (rc=%d)", errn, strerror(errn));

	lib3270_free(text);

}

LIB3270_EXPORT int lib3270_print(H3270 *hSession)
{
	if(check_online_session(hSession))
		return errno = ENOTCONN;

	return hSession->cbk.print(hSession, (hSession->selected ? LIB3270_CONTENT_SELECTED : LIB3270_CONTENT_ALL));
}

LIB3270_EXPORT int lib3270_print_all(H3270 *hSession)
{
	if(check_online_session(hSession))
		return errno = ENOTCONN;

	return hSession->cbk.print(hSession,LIB3270_CONTENT_ALL);
}

LIB3270_EXPORT int lib3270_print_selected(H3270 *hSession)
{
	if(check_online_session(hSession))
		return errno = ENOTCONN;

	if(hSession->selected)
		return hSession->cbk.print(hSession,LIB3270_CONTENT_SELECTED);

	return errno = ENODATA;
}

LIB3270_EXPORT int lib3270_print_copy(H3270 *hSession)
{
	if(check_online_session(hSession))
		return errno = ENOTCONN;

	return hSession->cbk.print(hSession,LIB3270_CONTENT_COPY);
}

LIB3270_EXPORT int lib3270_load(H3270 *hSession, const char *filename)
{
	if(check_online_session(hSession))
		return errno = ENOTCONN;

	return hSession->cbk.load(hSession, filename);
}

LIB3270_EXPORT int lib3270_save(H3270 *hSession, LIB3270_CONTENT_OPTION mode, const char *filename)
{
	return hSession->cbk.save(hSession, mode, filename);
}

LIB3270_EXPORT int lib3270_save_all(H3270 *hSession, const char *filename)
{
	if(check_online_session(hSession))
		return errno = ENOTCONN;

	return lib3270_save(hSession,LIB3270_CONTENT_ALL,filename);
}

LIB3270_EXPORT int lib3270_save_selected(H3270 *hSession, const char *filename)
{
	if(hSession->selected)
		return lib3270_save(hSession,LIB3270_CONTENT_SELECTED,filename);

	return errno = ENODATA;
}

LIB3270_EXPORT int lib3270_save_copy(H3270 *hSession, const char *filename)
{
	return lib3270_save(hSession,LIB3270_CONTENT_COPY,filename);
}

LIB3270_EXPORT LIB3270_POINTER lib3270_get_pointer(H3270 *hSession, int baddr)
{
	static const struct _ptr {
		unsigned short	id;
		LIB3270_POINTER	value;
	} ptr[] = {
		{ 0x80,	LIB3270_POINTER_MOVE_SELECTION			},
		{ 0x82,	LIB3270_POINTER_SELECTION_TOP			},
		{ 0x86,	LIB3270_POINTER_SELECTION_TOP_RIGHT		},
		{ 0x84,	LIB3270_POINTER_SELECTION_RIGHT			},
		{ 0x81,	LIB3270_POINTER_SELECTION_LEFT			},
		{ 0x89,	LIB3270_POINTER_SELECTION_BOTTOM_LEFT	},
		{ 0x88,	LIB3270_POINTER_SELECTION_BOTTOM		},
		{ 0x8c,	LIB3270_POINTER_SELECTION_BOTTOM_RIGHT	},
		{ 0x83,	LIB3270_POINTER_SELECTION_TOP_LEFT		}
	};

	size_t f;
	unsigned short id = lib3270_get_selection_flags(hSession,baddr) & 0x8f;

	if(!lib3270_is_connected(hSession) || baddr < 0)
		return LIB3270_POINTER_LOCKED;

	for(f = 0; f < (sizeof(ptr)/sizeof(ptr[0]));f++)
	{
		if(ptr[f].id == id)
		{
			return ptr[f].value;
		}
	}

	return hSession->pointer;

}

LIB3270_EXPORT int lib3270_getpeername(H3270 *hSession, struct sockaddr *addr, socklen_t *addrlen)
{
	CHECK_SESSION_HANDLE(hSession);

 	memset(addr,0,*addrlen);

 	if(hSession->sock < 0) {
		errno = ENOTCONN;
		return -1;
 	}

	return getpeername(hSession->sock, addr, addrlen);

}

LIB3270_EXPORT int lib3270_getsockname(H3270 *hSession, struct sockaddr *addr, socklen_t *addrlen)
{
	CHECK_SESSION_HANDLE(hSession);

 	memset(addr,0,*addrlen);

 	if(hSession->sock < 0) {
		errno = ENOTCONN;
		return -1;
 	}

	return getsockname(hSession->sock, addr, addrlen);
}

static int xdigit_value(const char scanner)
{

	if(scanner >= '0' && scanner <= '9') {
		return scanner - '0';
	}

	if(scanner >= 'A' && scanner <= 'F') {
		return 10 + (scanner - 'A');
	}

	if(scanner >= 'a' && scanner <= 'f') {
		return 10 + (scanner - 'a');
	}

	return -1;
}

static int unescape_character(const char *scanner)
{

		int first_digit 	= xdigit_value(*scanner++);
		int second_digit 	= xdigit_value(*scanner++);

		if (first_digit < 0)
				return -1;

		if (second_digit < 0)
				return -1;

		return (first_digit << 4) | second_digit;

}

char * lib3270_unescape(const char *text)
{
	if(!text)
		return NULL;

	size_t		  sz = strlen(text);
	char 		* outString = lib3270_malloc(sz+1);
	char		* dst = outString;
	const char	* src = text;
	char 		* ptr = strchr(src,'%');

	memset(outString,0,sz+1);

	while(ptr)
	{
		if(ptr[1] == '%')
		{
			src = ptr+2;
		}
		else
		{
			size_t sz = (ptr - src);
			memcpy(dst,src,sz);
			dst += sz;

			int chr = unescape_character(ptr+1);
			if(chr < 0)
			{
				*(dst++) = '?';
			}
			else
			{
				*(dst++) = (char) chr;
			}

			src += (sz+3);
		}

		ptr = strchr(src,'%');
	}

	strcpy(dst,src);

	return outString;
}