/* cavernlog.cc
 * Run cavern inside an Aven window
 *
 * Copyright (C) 2005,2006,2010,2011,2012,2014,2015 Olly Betts
 *
 * 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include "aven.h"
#include "cavernlog.h"
#include "filename.h"
#include "mainfrm.h"
#include "message.h"

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>

// For select():
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>

enum { LOG_REPROCESS = 1234 };

BEGIN_EVENT_TABLE(CavernLogWindow, wxHtmlWindow)
    EVT_BUTTON(LOG_REPROCESS, CavernLogWindow::OnReprocess)
    EVT_BUTTON(wxID_OK, CavernLogWindow::OnOK)
END_EVENT_TABLE()

static wxString escape_for_shell(wxString s, bool protect_dash = false)
{
    size_t p = 0;
#ifdef __WXMSW__
    bool needs_quotes = false;
    while (p < s.size()) {
	wxChar ch = s[p];
	if (ch < 127) {
	    if (ch == wxT('"')) {
		s.insert(p, 1, wxT('\\'));
		++p;
		needs_quotes = true;
	    } else if (strchr(" <>&|^", ch)) {
		needs_quotes = true;
	    }
	}
	++p;
    }
    if (needs_quotes) {
	s.insert(0u, 1, wxT('"'));
	s += wxT('"');
    }
#else
    if (protect_dash && !s.empty() && s[0u] == '-') {
	// If the filename starts with a '-', protect it from being
	// treated as an option by prepending "./".
	s.insert(0, wxT("./"));
	p = 2;
    }
    while (p < s.size()) {
	// Exclude a few safe characters which are common in filenames
	if (!isalnum(s[p]) && strchr("/._-", s[p]) == NULL) {
	    s.insert(p, 1, wxT('\\'));
	    ++p;
	}
	++p;
    }
#endif
    return s;
}

CavernLogWindow::CavernLogWindow(MainFrm * mainfrm_, wxWindow * parent)
    : wxHtmlWindow(parent), mainfrm(mainfrm_)
{
    int fsize = parent->GetFont().GetPointSize();
    int sizes[7] = { fsize, fsize, fsize, fsize, fsize, fsize, fsize };
    SetFonts(wxString(), wxString(), sizes);
}

void
CavernLogWindow::OnLinkClicked(const wxHtmlLinkInfo &link)
{
    wxString href = link.GetHref();
    wxString title = link.GetTarget();
    size_t colon = href.rfind(wxT(':'));
    if (colon == wxString::npos)
	return;
    size_t colon2 = href.rfind(wxT(':'), colon - 1);
    if (colon2 != wxString::npos) swap(colon, colon2);
#ifdef __WXMSW__
    wxString cmd = wxT("notepad $f");
#elif defined __WXMAC__
    wxString cmd = wxT("open -t $f");
#else
    wxString cmd = wxT("x-terminal-emulator -title $t -e vim +'call cursor($l,$c)' $f");
    // wxString cmd = wxT("gedit -b $f +$l:$c $f");
    // wxString cmd = wxT("x-terminal-emulator -title $t -e emacs +$l $f");
    // wxString cmd = wxT("x-terminal-emulator -title $t -e nano +$l $f");
    // wxString cmd = wxT("x-terminal-emulator -title $t -e jed -g $l $f");
#endif
    const char * p = getenv("SURVEXEDITOR");
    if (p) {
	cmd = wxString(p, wxConvUTF8);
	if (!cmd.find(wxT("$f"))) {
	    cmd += wxT(" $f");
	}
    }
    size_t i = 0;
    while ((i = cmd.find(wxT('$'), i)) != wxString::npos) {
	if (++i >= cmd.size()) break;
	switch ((int)cmd[i]) {
	    case wxT('$'):
		cmd.erase(i, 1);
		break;
	    case wxT('f'): {
		wxString f = escape_for_shell(href.substr(0, colon), true);
		cmd.replace(i - 1, 2, f);
		i += f.size() - 1;
		break;
	    }
	    case wxT('t'): {
		wxString t = escape_for_shell(title);
		cmd.replace(i - 1, 2, t);
		i += t.size() - 1;
		break;
	    }
	    case wxT('l'): {
		wxString l = escape_for_shell(href.substr(colon + 1, colon2 - colon - 1));
		cmd.replace(i - 1, 2, l);
		i += l.size() - 1;
		break;
	    }
	    case wxT('c'): {
		wxString l;
		if (colon2 == wxString::npos)
		    l = wxT("0");
		else
		    l = escape_for_shell(href.substr(colon2 + 1));
		cmd.replace(i - 1, 2, l);
		i += l.size() - 1;
		break;
	    }
	    default:
		++i;
	}
    }
#ifdef __WXMSW__
    if (_wsystem(cmd.c_str()) >= 0)
	return;
#else
    if (system(cmd.mb_str()) >= 0)
	return;
#endif
    wxString m;
    // TRANSLATORS: %s is replaced by the command we attempted to run.
    m.Printf(wmsg(/*Couldn’t run external command: “%s”*/17), cmd.c_str());
    m += wxT(" (");
    m += wxString(strerror(errno), wxConvUTF8);
    m += wxT(')');
    wxGetApp().ReportError(m);
}

int
CavernLogWindow::process(const wxString &file)
{
    SetFocus();
    filename = file;

#ifdef __WXMSW__
    SetEnvironmentVariable(wxT("SURVEX_UTF8"), wxT("1"));
#else
    setenv("SURVEX_UTF8", "1", 1);
#endif

    wxString escaped_file = escape_for_shell(file, true);
#ifdef __WXMSW__
    wxString cmd;
    {
	DWORD len = 256;
	wchar_t *buf = NULL;
	while (1) {
	    DWORD got;
	    buf = (wchar_t*)osrealloc(buf, len * 2);
	    got = GetModuleFileNameW(NULL, buf, len);
	    if (got < len) break;
	    len += len;
	}
	/* Strange Win32 nastiness - strip prefix "\\?\" if present */
	if (wcsncmp(buf, L"\\\\?\\", 4) == 0) buf += 4;
	wchar_t * slash = wcsrchr(buf, L'\\');
	if (slash) {
	    cmd.assign(buf, slash - buf + 1);
	}
    }
    cmd += L"cavern";
    cmd = escape_for_shell(cmd, false);
#else
    char *cavern = use_path(msg_exepth(), "cavern");
    wxString cmd = escape_for_shell(wxString(cavern, wxConvUTF8), false);
    osfree(cavern);
#endif
    cmd += wxT(" -o ");
    cmd += escaped_file;
    cmd += wxT(' ');
    cmd += escaped_file;

#ifdef __WXMSW__
    FILE * cavern_out = _wpopen(cmd.c_str(), L"r");
#else
    FILE * cavern_out = popen(cmd.mb_str(), "r");
#endif
    if (!cavern_out) {
	wxString m;
	m.Printf(wmsg(/*Couldn’t run external command: “%s”*/17), cmd.c_str());
	m += wxT(" (");
	m += wxString(strerror(errno), wxConvUTF8);
	m += wxT(')');
	wxGetApp().ReportError(m);
	return -2;
    }

    int cavern_fd;
#ifdef __WXMSW__
    cavern_fd = _fileno(cavern_out);
#else
    cavern_fd = fileno(cavern_out);
#endif
    assert(cavern_fd < FD_SETSIZE); // FIXME we shouldn't just assert, but what else to do?
    wxString cur;
    int link_count = 0;
    unsigned char buf[1024];
    unsigned char * end = buf;
    while (true) {
	fd_set rfds, efds;
	FD_ZERO(&rfds);
	FD_SET(cavern_fd, &rfds);
	FD_ZERO(&efds);
	FD_SET(cavern_fd, &efds);
	// Timeout instantly the first time, and call Update() so the window
	// contents get updated.  If we're still waiting for output after that,
	// wait for output for 0.1 seconds, then call wxYield() so that the UI
	// doesn't block.
	struct timeval timeout;
	timeout.tv_sec = 0;
	timeout.tv_usec = 0;
	bool first = true;
	while (select(cavern_fd + 1, &rfds, NULL, &efds, &timeout) == 0) {
	    if (first) {
		first = false;
		Update();
	    } else {
		wxYield();
	    }
	    FD_SET(cavern_fd, &rfds);
	    FD_SET(cavern_fd, &efds);
	    // Set timeout to 0.1 seconds.
	    timeout.tv_sec = 0;
	    timeout.tv_usec = 100000;
	}
	if (!FD_ISSET(cavern_fd, &rfds)) {
	    // Error, which pclose() should report.
	    break;
	}

	ssize_t r = read(cavern_fd, end, sizeof(buf) - (end - buf));
	if (r <= 0) {
	    if (r == 0 && buf != end) {
		// FIXME: Truncated UTF-8 sequence.
	    }
	    break;
	}
	end += r;

	const unsigned char * p = buf;

	while (p != end) {
	    int ch = *p++;
	    if (ch >= 0x80) {
		// Decode multi-byte UTF-8 sequence.
		if (ch < 0xc0) {
		    // FIXME: Invalid UTF-8 sequence.
		    goto abort;
		} else if (ch < 0xe0) {
		    /* 2 byte sequence */
		    if (p == end) {
			// Incomplete UTF-8 sequence - try to read more.
			break;
		    }
		    int ch1 = *p++;
		    if ((ch1 & 0xc0) != 0x80) {
			// FIXME: Invalid UTF-8 sequence.
			goto abort;
		    }
		    ch = ((ch & 0x1f) << 6) | (ch1 & 0x3f);
		} else if (ch < 0xf0) {
		    /* 3 byte sequence */
		    if (end - p <= 1) {
			// Incomplete UTF-8 sequence - try to read more.
			break;
		    }
		    int ch1 = *p++;
		    ch = ((ch & 0x1f) << 12) | ((ch1 & 0x3f) << 6);
		    if ((ch1 & 0xc0) != 0x80) {
			// FIXME: Invalid UTF-8 sequence.
			goto abort;
		    }
		    int ch2 = *p++;
		    if ((ch2 & 0xc0) != 0x80) {
			// FIXME: Invalid UTF-8 sequence.
			goto abort;
		    }
		    ch |= (ch2 & 0x3f);
		} else {
		    // FIXME: Overlong UTF-8 sequence.
		    goto abort;
		}
	    }

	    switch (ch) {
		case '\r':
		    // Ignore.
		    break;
		case '\n': {
		    if (cur.empty()) continue;
#ifndef __WXMSW__
		    size_t colon = cur.find(':');
#else
		    // If the path is "C:\path\to\file.svx" then don't split at the
		    // : after the drive letter!  FIXME: better to look for ": "?
		    size_t colon = cur.find(':', 2);
#endif
		    if (colon != wxString::npos && colon < cur.size() - 2) {
			++colon;
			size_t i = colon;
			while (i < cur.size() - 2 &&
			       cur[i] >= wxT('0') && cur[i] <= wxT('9')) {
			    ++i;
			}
			if (i > colon && cur[i] == wxT(':') ) {
			    colon = i;
			    // Check for column number.
			    while (++i < cur.size() - 2 &&
			       cur[i] >= wxT('0') && cur[i] <= wxT('9')) { }
			    if (i > colon + 1 && cur[i] == wxT(':') ) {
				colon = i;
			    }
			    wxString tag = wxT("<a href=\"");
			    tag.append(cur, 0, colon);
			    while (cur[++i] == wxT(' ')) { }
			    tag += wxT("\" target=\"");
			    tag.append(cur, i, wxString::npos);
			    tag += wxT("\">");
			    cur.insert(0, tag);
			    cur.insert(colon + tag.size(), wxT("</a>"));
			    ++link_count;
			}
		    }

		    // Save the scrollbar positions.
		    int scroll_x = 0, scroll_y = 0;
		    GetViewStart(&scroll_x, &scroll_y);

		    cur += wxT("<br>\n");
		    AppendToPage(cur);

		    if (!link_count) {
			// Auto-scroll the window until we've reported a warning or
			// error.
			int x, y;
			GetVirtualSize(&x, &y);
			int xs, ys;
			GetClientSize(&xs, &ys);
			y -= ys;
			int xu, yu;
			GetScrollPixelsPerUnit(&xu, &yu);
			Scroll(scroll_x, y / yu);
		    } else {
			// Restore the scrollbar positions.
			Scroll(scroll_x, scroll_y);
		    }

		    cur.clear();
		    break;
		}
		case '<':
		    cur += wxT("&lt;");
		    break;
		case '>':
		    cur += wxT("&gt;");
		    break;
		case '&':
		    cur += wxT("&amp;");
		    break;
		case '"':
		    cur += wxT("&#22;");
		    continue;
		default:
		    if (ch >= 128) {
			cur += wxString::Format(wxT("&#%u;"), ch);
		    } else {
			cur += (char)ch;
		    }
	    }
	}

	size_t left = end - p;
	end = buf + left;
	if (left) memmove(buf, p, left);
    }
abort:

    int retval = pclose(cavern_out);
    if (retval) {
	/* TRANSLATORS: Label for button in aven’s cavern log window which
	 * causes the survey data to be reprocessed. */
	AppendToPage(wxString::Format(wxT("<avenbutton default id=1234 name=\"%s\">"),
				      wmsg(/*Reprocess*/184).c_str()));
	if (retval == -1) {
	    wxString m = wxT("Problem running cavern: ");
	    m += wxString(strerror(errno), wxConvUTF8);
	    wxGetApp().ReportError(m);
	    return -2;
	}
	return -1;
    }
    if (link_count) {
	AppendToPage(wxString::Format(wxT("<avenbutton id=1234 name=\"%s\">"),
				      wmsg(/*Reprocess*/184).c_str()));
	AppendToPage(wxString::Format(wxT("<avenbutton default id=%d>"), (int)wxID_OK));
	Update();
    }
    return link_count;
}

void
CavernLogWindow::OnReprocess(wxCommandEvent & e)
{
    SetPage(wxString());
    if (process(filename) == 0) {
	OnOK(e);
    }
}

void
CavernLogWindow::OnOK(wxCommandEvent &)
{
    mainfrm->InitialiseAfterLoad(filename);
}