/*
 * "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.
 *
 * 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., 59 Temple
 * Place, Suite 330, Boston, MA, 02111-1307, USA
 *
 * Este programa está nomeado como hllapi.c e possui - linhas de código.
 *
 * Contatos:
 *
 * perry.werneck@gmail.com	(Alexandre Perry de Souza Werneck)
 * erico.mendonca@gmail.com	(Erico Mascarenhas Mendonça)
 *
 */

#include <algorithm>

#if defined(_MSC_VER)
	#define strncasecmp _strnicmp
	#define strcasecmp _stricmp
#else
	using std::min;
#endif

#include "private.h"
#include <lib3270/hllapi.h>


/*--[ Prototipes ]-----------------------------------------------------------------------------------*/

 static int connect_ps(char *buffer, unsigned short *length, unsigned short *rc);
 static int disconnect_ps(char *buffer, unsigned short *length, unsigned short *rc);
 static int get_library_revision(char *buffer, unsigned short *length, unsigned short *rc);
 static int copy_ps_to_str(char *buffer, unsigned short *length, unsigned short *rc);
 static int copy_str_to_ps(char *buffer, unsigned short *length, unsigned short *rc);
 static int search_ps(char *buffer, unsigned short *length, unsigned short *rc);
 static int copy_ps(char *buffer, unsigned short *length, unsigned short *rc);
 static int wait_system(char *buffer, unsigned short *length, unsigned short *rc);
 static int reset_system(char *buffer, unsigned short *length, unsigned short *rc);
 static int pause_system(char *buffer, unsigned short *length, unsigned short *rc);
 static int set_session_parameters(char *buffer, unsigned short *length, unsigned short *rc);

 static int get_cursor_position(char *buffer, unsigned short *length, unsigned short *rc);
 static int set_cursor_position(char *buffer, unsigned short *length, unsigned short *rc);
 static int input_string(char *buffer, unsigned short *length, unsigned short *rc);

 static int invalid_request(char *buffer, unsigned short *length, unsigned short *rc);

/*--[ Globals ]--------------------------------------------------------------------------------------*/

 static const struct _hllapi_call
 {
	unsigned long func;
	int (*exec)(char *buffer, unsigned short *length, unsigned short *rc);
 } hllapi_call[] =
 {
	{ HLLAPI_CMD_CONNECTPS,				connect_ps				},
	{ HLLAPI_CMD_DISCONNECTPS,			disconnect_ps			},
	{ HLLAPI_CMD_GETREVISION,			get_library_revision	},
	{ HLLAPI_CMD_QUERYCURSOR,			get_cursor_position		},
	{ HLLAPI_CMD_SETCURSOR,				set_cursor_position		},
	{ HLLAPI_CMD_COPYPSTOSTR,			copy_ps_to_str			},
	{ HLLAPI_CMD_INPUTSTRING,			input_string			},
	{ HLLAPI_CMD_WAIT,					wait_system				},
	{ HLLAPI_CMD_COPYPS,				copy_ps					},
	{ HLLAPI_CMD_SEARCHPS,				search_ps				},
	{ HLLAPI_CMD_COPYSTRTOPS,			copy_str_to_ps			},
	{ HLLAPI_CMD_SENDFILE,				invalid_request			},
	{ HLLAPI_CMD_RECEIVEFILE,			invalid_request			},
	{ HLLAPI_RESET_SYSTEM,				reset_system			},
	{ HLLAPI_CMD_PAUSE,					pause_system			},
	{ HLLAPI_SET_SESSION_PARAMETERS,	set_session_parameters	}

 };

 static enum _pause_mode
 {
	PAUSE_MODE_IPAUSE,		///< @brief Interruptible pause. After the Start Host Notification (23) function is executed, a host event satisfies a pause.
	PAUSE_MODE_FPAUSE		///< @brief A full-duration pause lasts for however long you specified in the Pause (18) function.
 } pause_mode = PAUSE_MODE_IPAUSE;

/*--[ Implement ]------------------------------------------------------------------------------------*/

HLLAPI_API_CALL hllapi(const LPWORD func, LPSTR buffer, LPWORD length, LPWORD rc) {

	for(unsigned int f=0;f < (sizeof (hllapi_call) / sizeof ((hllapi_call)[0]));f++) {

		if(hllapi_call[f].func == *func) {

			try {

				return hllapi_call[f].exec(buffer,length,rc);

			} catch(std::exception &e) {

				hllapi_lasterror = e.what();
				*rc = HLLAPI_STATUS_SYSTEM_ERROR;
				return *rc;

			}

		}

	}

	trace("hllapi(%d) failed",*func);

	*rc = HLLAPI_STATUS_UNSUPPORTED;
	return *rc;

}

static int invalid_request(char GNUC_UNUSED(*buffer), unsigned short GNUC_UNUSED(*length), unsigned short *rc) {
	*rc = HLLAPI_STATUS_BAD_PARAMETER;
	return *rc;
}

static int connect_ps(char *buffer, unsigned short *length, unsigned short *rc) {

	char *tempbuffer = NULL;

	trace("%s: len=%d buflen=%d",__FUNCTION__,*length,(int) strlen(buffer));

	if(strlen(buffer) > *length)
		buffer[*length] = 0;

	if(!strrchr(buffer,':'))
	{
		int sz = strlen(buffer);

		tempbuffer = (char *) malloc(sz+2);
		strcpy(tempbuffer,buffer);
		tempbuffer[sz-1] = ':';
		tempbuffer[sz]   = buffer[sz-1];
		tempbuffer[sz+1] = 0;
		buffer = tempbuffer;
	}

	*rc = hllapi_init(buffer);

	if(tempbuffer)
		free(tempbuffer);

	return HLLAPI_STATUS_SUCCESS;

}

static int disconnect_ps(char GNUC_UNUSED(*buffer), unsigned short GNUC_UNUSED(*length), unsigned short *rc) {
	*rc = hllapi_deinit();
	return HLLAPI_STATUS_SUCCESS;
}

static int get_library_revision(char GNUC_UNUSED(*buffer), unsigned short GNUC_UNUSED(*length), unsigned short *rc) {
	*rc = hllapi_get_revision();
	return HLLAPI_STATUS_SUCCESS;
}

static int get_cursor_position(char GNUC_UNUSED(*buffer), unsigned short GNUC_UNUSED(*length), unsigned short *rc) {

 	try {

		TN3270::Host &host = getSession();

		if(!host.isConnected())
			return HLLAPI_STATUS_DISCONNECTED;

		*rc = (unsigned short) (host.getCursorAddress()+1);

	} catch(std::exception &e) {

		hllapi_lasterror = e.what();
		return HLLAPI_STATUS_SYSTEM_ERROR;

	}

	return HLLAPI_STATUS_SUCCESS;

}

static int set_cursor_position(char GNUC_UNUSED(*buffer), unsigned short GNUC_UNUSED(*length), unsigned short *rc) {

 	try {

		TN3270::Host &host = getSession();

		if(!host.isConnected()) {
			hllapi_lasterror = _( "Disconnected from host" );
			return HLLAPI_STATUS_DISCONNECTED;
		}

		host.setCursor((unsigned short) *rc -1);

		return HLLAPI_STATUS_SUCCESS;

	} catch(std::exception &e) {

		hllapi_lasterror = e.what();

	}

	return HLLAPI_STATUS_SYSTEM_ERROR;

}

static int copy_ps_to_str(char *buffer, unsigned short *length, unsigned short *rc) {

	// Length		Length of the target data string.
	// PS Position	Position within the host presentation space of the first byte in your target data string.
	*rc = hllapi_get_screen(*rc,buffer,*length);

	return HLLAPI_STATUS_SUCCESS;
}

static int input_string(char *buffer, unsigned short *length, unsigned short *rc) {
	*rc = hllapi_input_string(buffer,*length);
	return HLLAPI_STATUS_SUCCESS;
}

static int search_ps(char *buffer, unsigned short *length, unsigned short *ps) {

	//
	// Data String	Target string for search.
	// Length	Length of the target data string. Overridden in EOT mode.
	//
	// PS Position	Position within the host presentation space where the search is to begin (SRCHFRWD option) or to end
	// (SRCHBKWD option). Overridden in SRCHALL (default) mode.
	//
	//  Return in *ps:
	//
	//  = 0	The string was not found.
	//  > 0	The string was found at the indicated host presentation space position.
	//
	//  Return code:
	//
	//  0	HLLAPI_STATUS_SUCCESS		The Search Presentation Space function was successful.
	//  1	HLLAPI_STATUS_DISCONNECTED	Your program is not connected to a host session.
	//  2	HLLAPI_STATUS_BAD_PARAMETER	An error was made in specifying parameters.
	//  7	HLLAPI_STATUS_BAD_POSITION	The host presentation space position is not valid.
	//  9	HLLAPI_STATUS_SYSTEM_ERROR	A system error was encountered.
	// 24	HLLAPI_STATUS_NOT_FOUND		The search string was not found.
	//
	//

 	try {

		size_t pos = string::npos;

		if(length) {

			pos = getSession().find(string((const char *) buffer,(size_t) length).c_str());

		} else {

			pos = getSession().find(buffer);

		}

		if(pos == string::npos) {
			*ps = 0;
			return HLLAPI_STATUS_NOT_FOUND;
		}

		*ps = pos;

		return HLLAPI_STATUS_SUCCESS;

	} catch(const std::system_error &e) {

		return hllapi_translate_error(e);

	} catch(std::exception &e) {

		hllapi_lasterror = e.what();

	}

	return HLLAPI_STATUS_SYSTEM_ERROR;

}

static int copy_ps(char *buffer, unsigned short *length, unsigned short GNUC_UNUSED(*rc)) {

	//
	// Data String	Preallocated target string the size of your host presentation space. This can vary depending on how your host presentation space
	//				is configured. When the Set Session Parameters (9) function with the EAB option is issued, the length of the data string must be
	//				at least twice the length of the presentation space.
	//				DBCS Only: When the EAD option is specified, the length of the data string must be at least three times the length of the
	//				presentation space. When both the EAB and EAD options are specified, the length of the data string must be at least four times
	//				the length of the presentation space.
	//
	// Length		NA (the length of the host presentation space is implied).
	// PS Position	NA.
	//
	// Return values:
	//
	// 0	HLLAPI_STATUS_SUCCESS			The host presentation space contents were copied to the application program. The target presentation space was active, and the keyboard was unlocked.
	// 1	HLLAPI_STATUS_DISCONNECTED		Your program is not connected to a host session.
	// 4	HLLAPI_STATUS_TIMEOUT			The host presentation space contents were copied. The connected host presentation space was waiting for host response.
	// 5	HLLAPI_STATUS_KEYBOARD_LOCKED	The host presentation space was copied. The keyboard was locked.
	// 9	HLLAPI_STATUS_SYSTEM_ERROR		A system error was encountered.
	//
	//
 	try {

		TN3270::Host &host = getSession();

		if(!host.isConnected()) {
			hllapi_lasterror = _( "Disconnected from host" );
			return HLLAPI_STATUS_DISCONNECTED;
		}

		string contents = host.toString(0,-1,'\0');

		size_t szBuffer = min(contents.size(), ((size_t) *length));
		*length = (unsigned short) szBuffer;

		strncpy(buffer,contents.c_str(),szBuffer);

		return hllapi_get_state();

	} catch(std::exception &e) {

		hllapi_lasterror = e.what();

	}

	return HLLAPI_STATUS_SYSTEM_ERROR;

}

static int wait_system(char GNUC_UNUSED(*buffer), unsigned short GNUC_UNUSED(*length), unsigned short *rc) {

	//
	// Checks the status of the host-connected presentation space. If the session is
	// waiting for a host response (indicated by XCLOCK (X []) or XSYSTEM), the Wait
	// function causes HLLAPI to wait up to 1 minute to see if the condition clears.
	//
	//

	//
	// Return Code	Definition
	//
	// HLLAPI_STATUS_SUCCESS			0	The keyboard is unlocked and ready for input.
	// HLLAPI_STATUS_DISCONNECTED		1	Your application program is not connected to a valid session.
	// HLLAPI_STATUS_TIMEOUT			4	Timeout while still in XCLOCK (X []) or XSYSTEM.
	// HLLAPI_STATUS_KEYBOARD_LOCKED	5	The keyboard is locked.
	// HLLAPI_STATUS_SYSTEM_ERROR		9	A system error was encountered.
	//
	//

	int state = hllapi_wait_for_ready(60);
	*rc = (unsigned short) state;
	return (state == HLLAPI_STATUS_WAITING ? HLLAPI_STATUS_TIMEOUT : state);

}

static int copy_str_to_ps(char *text, unsigned short *length, unsigned short *ps) {
	//
	// Call Parameters
	//
	// Data 	String of ASCII data to be copied into the host presentation space.
	// Length	Length, in number of bytes, of the source data string. Overridden if in EOT mode.
	// PS 		Position in the host presentation space to begin the copy, a value between 1 and the configured size of your host presentation space.
	//
	// Return Parameters
	//
	// HLLAPI_STATUS_SUCCESS			0	The Copy String to Presentation Space function was successful.
	// HLLAPI_STATUS_DISCONNECTED		1	Your program is not connected to a host session.
	// HLLAPI_STATUS_BAD_PARAMETER		2	Parameter error or zero length for copy.
	// HLLAPI_STATUS_KEYBOARD_LOCKED	5	The target presentation space is protected or inhibited, or incorrect data was sent to the target presentation space (such as a field attribute byte).
	// 									6	The copy was completed, but the data was truncated.
	// 									7	The host presentation space position is not valid.
	// HLLAPI_STATUS_SYSTEM_ERROR		9	A system error was encountered.
	//
	//
	*ps = 0;
	return hllapi_emulate_input(text,*length,0);
}

static int reset_system(char GNUC_UNUSED(*buffer), unsigned short GNUC_UNUSED(*length), unsigned short *rc) {
	int state = hllapi_kybdreset();
	*rc = (unsigned short) state;
	return state;
}


static int pause_system(char GNUC_UNUSED(*buffer), unsigned short *length, unsigned short *rc) {

	if(!*length)
	{
		// If you use the IPAUSE option and the pause value is zero, then the function
		// waits up to 2400 half-second intervals, unless interrupted sooner. If you use the
		// FPAUSE option and the pause value is zero, then the function returns
		// immediately.

		if(pause_mode == PAUSE_MODE_FPAUSE)
		{
			return HLLAPI_STATUS_SUCCESS;
		}
		return hllapi_wait_for_ready(1200);
	}

	if(pause_mode == PAUSE_MODE_FPAUSE)
	{
		// Pause fixo - Aguarda pelo tempo informado, independente de eventos.
		return hllapi_wait( (*length) / 2);
	}

	// Pause "flexivel", aguarda mudança no conteúdo da tela!!!
	int state = hllapi_wait_for_change((*length) / 2);

	*rc = (unsigned short) state;
	return state;

}

static int set_session_parameters(char *buffer, unsigned short *length, unsigned short *rc)
{
	if(!(*length && buffer && *buffer))
	{
		return HLLAPI_STATUS_BAD_PARAMETER;
	}

	*rc = hllapi_set_session_parameter(buffer, *length, *rc);

	return HLLAPI_STATUS_SUCCESS;
}

HLLAPI_API_CALL hllapi_set_session_parameter(LPSTR param, WORD len, WORD value)
{
 	if(!param)
		return HLLAPI_STATUS_BAD_PARAMETER;

	if(!len)
		len = strlen(param);

	if(!strncasecmp(param,"IPAUSE",len)) {

		// IPAUSE
		pause_mode = PAUSE_MODE_IPAUSE;

	} else if(!strncasecmp(param,"FPAUSE",len)) {

		// FPAUSE
		pause_mode = PAUSE_MODE_FPAUSE;

	} else if(!strncasecmp(param,"UNLOCKDELAY",len)) {

		// UNLOCKDELAY
		hllapi_set_unlock_delay(value);

	} else if(!strncasecmp(param,"TIMEOUT",len)) {

		// UNLOCKDELAY
		hllapi_set_timeout(value);

	} else {

		int rc = HLLAPI_STATUS_BAD_PARAMETER;

		try {

			string buffer = std::to_string((unsigned int) value);
			getSession().setProperty(param,buffer.c_str());

		} catch(const std::system_error &e) {

			rc = hllapi_translate_error(e);

		} catch(const std::exception &e) {

			// Error getting session or lock state
			hllapi_lasterror = e.what();
			rc = HLLAPI_STATUS_SYSTEM_ERROR;

		} catch(...) {

			// Unexpected error getting session or lock state
			hllapi_lasterror = _( "Unexpected error" );
			rc = HLLAPI_STATUS_SYSTEM_ERROR;

		}

		return rc;

	}

	return HLLAPI_STATUS_SUCCESS;
}