/*
 * MiniTerminal - A basic windowed terminal to allow
 * command-line interaction from within app_server.
 * Based on consoled and MuTerminal.
 *
 * Copyright 2005 Michael Lotz. All rights reserved.
 * Distributed under the MIT License.
 *
 * Copyright 2004-2005, Haiku. All rights reserved.
 * Distributed under the terms of the MIT License.
 *
 * Copyright 2002, Travis Geiselbrecht. All rights reserved.
 * Distributed under the terms of the NewOS License.
 */


#include <OS.h>
#include <image.h>
#include <Message.h>
#include <Window.h>

#include <termios.h>
#include <unistd.h>
#include <dirent.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>

#include "Arguments.h"
#include "Console.h"
#include "MiniView.h"

#include "VTkeymap.h"

//#define TRACE_MINI_TERMINAL
#ifdef TRACE_MINI_TERMINAL
	#ifdef __HAIKU__
	#define TRACE(x)	debug_printf x
	#else
	#define	TRACE(x)	printf x
	#endif
#else
	#define TRACE(x)
#endif

void
Setenv(const char *var, const char *value)
{
	int envindex = 0;
	const int len = strlen(var);
	const int val_len = strlen (value);
  
	while (environ [envindex] != NULL) {
		if (strncmp (environ [envindex], var, len) == 0) {
			/* found it */
			// TODO: shouldn't we free the old variable first?
			environ[envindex] = (char *)malloc ((unsigned)len + val_len + 2);
			sprintf (environ [envindex], "%s=%s", var, value);
			return;
		}
		envindex ++;
	}
	
	environ [envindex] = (char *) malloc ((unsigned)len + val_len + 2);
	sprintf (environ [envindex], "%s=%s", var, value);
	environ [++envindex] = NULL;
}

MiniView::MiniView(const Arguments &args)
	:	ViewBuffer(args.Bounds().OffsetToCopy(0, 0)),
		fArguments(args)
{
	// we need a message filter so that we get B_TAB keydowns
	AddFilter(new BMessageFilter(B_KEY_DOWN, &MiniView::MessageFilter));
}

MiniView::~MiniView()
{
	kill_thread(fConsoleWriter);
	kill_thread(fShellExecutor);
	kill_thread(fShellProcess);
}

void
MiniView::Start()
{
	fConsole = new Console(this);
	
	if (OpenTTY() != B_OK) {
		TRACE(("error in OpenTTY\n"));
		return;
	}
	
	// we're a session leader
	setsid();
	
	if (SpawnThreads() != B_OK)
		TRACE(("error in SpawnThreads\n"));
}

status_t
MiniView::OpenTTY()
{
	DIR *dir;
	
	dir = opendir("/dev/pt");
	if (dir != NULL) {
		struct dirent *entry;
		char name[64];
		
		while ((entry = readdir(dir)) != NULL) {
			if (entry->d_name[0] == '.') // filter out . and ..
				continue;
			
			sprintf(name, "/dev/pt/%s", entry->d_name);
			
			fMasterFD = open(name, O_RDWR);
			if (fMasterFD >= 0) {
				sprintf(name, "/dev/tt/%s", entry->d_name);
				
				fSlaveFD = open(name, O_RDWR);
				if (fSlaveFD < 0) {
					TRACE(("cannot open tty\n"));
					close(fMasterFD);
				} else {
					struct termios tio;
					tcgetattr(fSlaveFD, &tio);
					
					// set signal default
					signal(SIGCHLD, SIG_DFL);
					signal(SIGHUP, SIG_DFL);
					signal(SIGQUIT, SIG_DFL);
					signal(SIGTERM, SIG_DFL);
					signal(SIGINT, SIG_DFL);
					signal(SIGTTOU, SIG_DFL);
					
					// set terminal interface
					tio.c_line = 0;
					tio.c_lflag |= ECHOE; 
					
					// input: nl->nl, cr->nl
					tio.c_iflag &= ~(INLCR|IGNCR);
					tio.c_iflag |= ICRNL;
					tio.c_iflag &= ~ISTRIP;
					
					// output: cr->cr, nl in not retrun, no delays, ln->cr/ln
					tio.c_oflag &= ~(OCRNL|ONLRET|NLDLY|CRDLY|TABDLY|BSDLY|VTDLY|FFDLY);
					tio.c_oflag |= ONLCR;
					tio.c_oflag |= OPOST;
					
					// baud rate is 19200 (equal to beterm)
					tio.c_cflag &= ~(CBAUD);
					tio.c_cflag |= B19200;
					
					tio.c_cflag &= ~CSIZE;
					tio.c_cflag |= CS8;
					tio.c_cflag |= CREAD;
					
					tio.c_cflag |= HUPCL;
					tio.c_iflag &= ~(IGNBRK|BRKINT);
					
					// enable signals, canonical processing (erase, kill, etc), echo
					tio.c_lflag |= ISIG|ICANON|ECHO|ECHOE|ECHONL;
					tio.c_lflag &= ~ECHOK;
					
					tio.c_lflag &= ~IEXTEN;
					
					// set control charactors
					tio.c_cc[VINTR]  = 'C' & 0x1f;	/* '^C'	*/
					tio.c_cc[VQUIT]  = '\\'& 0x1f;	/* '^\'	*/
					tio.c_cc[VERASE] = 0x08;		/* '^H'	*/
					tio.c_cc[VKILL]  = 'U' & 0x1f;	/* '^U'	*/
					tio.c_cc[VEOF]   = 'D' & 0x1f;	/* '^D' */
					tio.c_cc[VEOL]   = 0;			/* '^@' */
					tio.c_cc[VMIN]   = 4;
					tio.c_cc[VTIME]  = 0;
					tio.c_cc[VEOL2]  = 0;			/* '^@' */
					tio.c_cc[VSWTCH] = 0;			/* '^@' */
					tio.c_cc[VSTART] = 'S' & 0x1f;	/* '^S' */
					tio.c_cc[VSTOP]  = 'Q' & 0x1f;	/* '^Q' */
					tio.c_cc[VSUSP]  = '@' & 0x1f;	/* '^@' */
					
					// set terminal interface
					tcsetattr(fSlaveFD, TCSANOW, &tio);
					
					// set window size
					winsize ws;
					int32 rows, cols;
					GetSize(&cols, &rows);
					ws.ws_row = rows;
					ws.ws_col = cols;
					if (LockLooper()) {
						ws.ws_xpixel = Bounds().IntegerWidth();
						ws.ws_ypixel = Bounds().IntegerHeight();
						UnlockLooper();
					}
					ioctl(fSlaveFD, TIOCSWINSZ, &ws);
				}
				break;
			}
		}
		
		
		Setenv("TTY", name);
	}
	
	if (fMasterFD < 0 || fSlaveFD < 0) {
		TRACE(("could not open master or slave fd\n"));
		return B_ERROR;
	}
	
	Setenv("TERM", "beterm");
	return B_OK;
}

void
MiniView::FrameResized(float width, float height)
{
	ViewBuffer::FrameResized(width, height);
	
	winsize ws;
	int32 rows, cols;
	GetSize(&cols, &rows);
	ws.ws_row = rows;
	ws.ws_col = cols;
	ws.ws_xpixel = (uint16)width;
	ws.ws_ypixel = (uint16)height;
	ioctl(fSlaveFD, TIOCSWINSZ, &ws);
}


void
MiniView::KeyDown(const char *bytes, int32 numBytes)
{
	// TODO: add interrupt char handling
	uint32 mod = modifiers();
	if (numBytes == 1) {
		if (mod & B_OPTION_KEY) {
			char c = bytes[0] | 0x80;
			write(fMasterFD, &c, 1);
		} else {
			switch (bytes[0]) {
				case B_LEFT_ARROW:
					write(fMasterFD, LEFT_ARROW_KEY_CODE, sizeof(LEFT_ARROW_KEY_CODE) - 1);
					break;
				case B_RIGHT_ARROW:
					write(fMasterFD, RIGHT_ARROW_KEY_CODE, sizeof(RIGHT_ARROW_KEY_CODE) - 1);
					break;
				case B_UP_ARROW:
					write(fMasterFD, UP_ARROW_KEY_CODE, sizeof(UP_ARROW_KEY_CODE) - 1);
					break;
				case B_DOWN_ARROW:
					write(fMasterFD, DOWN_ARROW_KEY_CODE, sizeof(DOWN_ARROW_KEY_CODE) - 1);
					break;
				default:
					write(fMasterFD, bytes, numBytes);
			}
		}
	} else
		write(fMasterFD, bytes, numBytes);
}

status_t
MiniView::SpawnThreads()
{
	fConsoleWriter = spawn_thread(&MiniView::ConsoleWriter, "console writer", B_URGENT_DISPLAY_PRIORITY, this);
	if (fConsoleWriter < 0)
		return B_ERROR;
	TRACE(("console writer thread is: %ld\n", fConsoleWriter));
	
	fShellExecutor = spawn_thread(&MiniView::ExecuteShell, "shell process", B_URGENT_DISPLAY_PRIORITY, this);
	if (fShellExecutor < 0)
		return B_ERROR;
	TRACE(("shell executor thread is: %ld\n", fShellExecutor));
	
	resume_thread(fConsoleWriter);
	resume_thread(fShellExecutor);
	return B_OK;
}

int32
MiniView::ConsoleWriter(void *arg)
{
	char buf[1024];
	ssize_t len;
	MiniView *view = (MiniView *)arg;
	
	for (;;) {
		len = read(view->fMasterFD, buf, sizeof(buf));
		if (len < 0)
			break;
		
		view->fConsole->Write(buf, len);
	}
	
	return 0;
}

int32
MiniView::ExecuteShell(void *arg)
{
	MiniView *view = (MiniView *)arg;
	
	for (;;) {
		int argc;
		const char *const *argv;
		view->fArguments.GetShellArguments(argc, argv);

		int saved_stdin = dup(0);
		int saved_stdout = dup(1);
		int saved_stderr = dup(2);
		
		dup2(view->fSlaveFD, 0);
		dup2(view->fSlaveFD, 1);
		dup2(view->fSlaveFD, 2);

		view->fShellProcess = load_image(argc, (const char **)argv,
			(const char **)environ);
		setpgid(view->fShellProcess, 0);
		tcsetpgrp(view->fSlaveFD, view->fShellProcess);

		dup2(saved_stdin, 0);
		dup2(saved_stdout, 1);
		dup2(saved_stderr, 2);
		close(saved_stdin);
		close(saved_stdout);
		close(saved_stderr);

		status_t return_code;
		wait_for_thread(view->fShellProcess, &return_code);
		
		if (!view->fArguments.StandardShell()) {
			view->Window()->PostMessage(B_QUIT_REQUESTED);
			break;
		}
	}
	
	return B_OK;
}

filter_result
MiniView::MessageFilter(BMessage *message, BHandler **target, BMessageFilter *filter)
{
	MiniView *view = (MiniView *)(*target);
	
	int32 raw_char;
	message->FindInt32("raw_char", &raw_char);
	if (raw_char == B_TAB) {
		char bytes[2] = { B_TAB, 0 };
		view->KeyDown(bytes, 1);
		return B_SKIP_MESSAGE;
	}
	
	return B_DISPATCH_MESSAGE;
}