// -*- C++ -*-
/**
 * \file path_defines.C
 * This file is part of LyX, the document processor.
 * Licence details can be found in the file COPYING.
 *
 * \author Angus Leeming
 *
 * Full author contact details are available in file CREDITS.
 *
 * Warning! This file is autogenerated from path_defines.C.in.
 * All changes to this file will be lost.
 */

#include <config.h>

#include "path_defines.h"

#include "debug.h"
#include "gettext.h"

#include "FileInfo.h"
#include "filetools.h"
#include "lstrings.h"
#include "os.h"
#include "lyxlib.h"

using std::string;
using std::endl;


namespace {

// Store for the path to the lyx support files we're actually going to use.
string system_lyxdir_;

// Store for the path to the autogenerated files when running in place
string build_lyxdir_;

// Store for the path to the user-level support files.
string user_lyxdir_;

// Store for the path to the locale directory.
string localedir_;

/* The absolute path to the system-level lyx support files.
 * (Make-time value.)
 */
string const & lyx_dir()
{
	static string const ld = "%LYX_DIR%";
	return ld;
}

} // namespace anon


namespace lyx {
namespace support {


/* The absolute path to the top of the lyx build tree.
 * (Make-time value.)
 */
string const & top_srcdir()
{
	static string const lts = "%TOP_SRCDIR%";
	return lts;
}


/* The absolute path to the system-level lyx locale directory.
 * (Make-time value.)
 */
string const & lyx_localedir()
{
	static string const ll = "%LOCALEDIR%";
	if (localedir_.empty())
		return ll;
	else
		return localedir_;
}


string const & build_dir()
{
	static string const bl = "%BUILDDIR%";
	return bl;
}


string const & build_lyxdir()
{
	return build_lyxdir_;
}


void build_lyxdir(string const & sld)
{
	build_lyxdir_ = sld;
}


string const & system_lyxdir()
{
	return system_lyxdir_;
}


void system_lyxdir(string const & sld)
{
	system_lyxdir_ = sld;
}


string const & user_lyxdir()
{
	return user_lyxdir_;
}


void user_lyxdir(string const & uld)
{
	user_lyxdir_ = uld;
}


bool setLyxPaths()
{
	//
	// Determine path of binary
	//

	string binpath = os::binpath();
	string binname = os::binname();
	string fullbinname = MakeAbsPath(binname, binpath);

	if (binpath.empty()) {
		lyxerr << _("Warning: could not determine path of binary.")
		       << "\n"
		       << _("If you have problems, try starting LyX with an absolute path.")
		       << endl;
	}
	lyxerr[Debug::INIT] << "Name of binary: " << binname << endl;
	lyxerr[Debug::INIT] << "Path of binary: " << binpath << endl;


	string searchpath;

	//
	// Determine whether we are running in place and set
	// build_lyxdir accordingly
	//

	string const buildlyxdir = MakeAbsPath("../lib", binpath);
	if (!FileSearch(buildlyxdir, "lyxrc.defaults").empty()) {
		searchpath += AddPath(top_srcdir(), "lib") + ';';
		build_lyxdir(buildlyxdir);
		lyxerr[Debug::INIT] << "Checking whether LyX is run in "
			"place... yes" << endl;
	} else {
		lyxerr[Debug::INIT]
			<< "Checking whether LyX is run in place... no"
			<< endl;
	}

	//
	// Determine system directory.
	//

	// Directories are searched in this order:
	// 1) -sysdir command line parameter
	// 2) LYX_DIR_14x environment variable
	// 3) Maybe <path of binary>/TOP_SRCDIR/lib
	// 4) <path of binary>/../Resources/<name of binary>/  [for LyX/Mac]
	// 5) <path of binary>/../share/<name of binary>/
	// 5a) repeat 4 after following the Symlink if <path of
	//     binary> is a symbolic link.
	// 6) hardcoded lyx_dir
	// The directory is checked for the presence of the file
	// "chkconfig.ltx", and if that is present, the directory
	// is accepted as the system directory.
	// If no chkconfig.ltx file is found, a warning is given,
	// and the hardcoded lyx_dir is used.

	// If we had a command line switch, system_lyxdir_ is already set
	if (!system_lyxdir_.empty())
		searchpath = MakeAbsPath(system_lyxdir_) + ';';

	string const lyxdir = GetEnvPath("LYX_DIR_14x");

	if (!lyxdir.empty()) {
		lyxerr[Debug::INIT] << "LYX_DIR_14x: " << lyxdir << endl;
		searchpath += lyxdir + ';';
	}

	// Path of binary/../Resources/
	searchpath += NormalizePath(AddPath(binpath, "../Resources/") +
				    OnlyFilename(binname)) + ';';

	string fullbinpath = binpath;
	FileInfo file(fullbinname, true);
	if (file.isLink()) {
		lyxerr[Debug::INIT] << "binary is a link" << endl;
		string link;
		if (LyXReadLink(fullbinname, link, true)) {
			// Path of binary/../share/name of binary/
			searchpath += NormalizePath(AddPath(binpath,
							    "../share/")
						    + OnlyFilename(binname));
			searchpath += ';';
			fullbinpath = link;
			binpath = MakeAbsPath(OnlyPath(fullbinpath));
		}
	}

	bool followlink;
	do {
		// Path of binary/../share/name of binary/
		searchpath += NormalizePath(AddPath(binpath, "../share/") +
		      OnlyFilename(binname)) + ';';

		// Follow Symlinks
		FileInfo file(fullbinpath, true);
		followlink = file.isLink();
		if (followlink) {
			lyxerr[Debug::INIT] << " directory " << fullbinpath
					    << " is a link" << endl;
			string link;
			if (LyXReadLink(fullbinpath, link, true)) {
				fullbinpath = link;
				binpath = MakeAbsPath(OnlyPath(fullbinpath));
			}
			else {
				followlink = false;
			}
		}
	} while (followlink);

	// <absolute top srcdir>/lib
	searchpath += AddPath(top_srcdir(), "lib") + ';';
	// Hardcoded dir
	searchpath += lyx_dir();

	lyxerr[Debug::INIT] << "System directory search path: "
			    << searchpath << endl;

	string const filename = "chkconfig.ltx";
	string const temp = FileOpenSearch(searchpath, filename, string());
	system_lyxdir_ = OnlyPath(temp);

	// Reduce "path/../path" stuff out of system directory
	system_lyxdir_ = NormalizePath(system_lyxdir_);

	bool path_shown = false;

	// Warn if environment variable is set, but unusable
	if (!lyxdir.empty()) {
		if (system_lyxdir_ != NormalizePath(lyxdir)) {
			lyxerr <<_("LYX_DIR_14x environment variable no good.")
			       << '\n'
			       << _("System directory set to: ")
			       << system_lyxdir_ << endl;
			path_shown = true;
		}
	}

	// Warn the user if we couldn't find "chkconfig.ltx"
	if (system_lyxdir_ == "./") {
		lyxerr <<_("LyX Warning! Couldn't determine system directory. ")
		       <<_("Try the '-sysdir' command line parameter or ")
		       <<_("set the environment variable LYX_DIR_14x to the "
			   "LyX system directory ")
		       << _("containing the file `chkconfig.ltx'.") << endl;
		if (!path_shown) {
			FileInfo fi(lyx_dir());
			if (!fi.exist()) {
				lyxerr << "Couldn't even find the default LYX_DIR." << endl
					<< "Giving up." << endl;
				exit(1);
			}
			lyxerr << bformat(_("Using built-in default %1$s but expect problems."),
				lyx_dir()) << endl;
		} else {
			lyxerr << _("Expect problems.") << endl;
		}
		system_lyxdir_ = lyx_dir();
		path_shown = true;
	}

	if (!path_shown)
		lyxerr[Debug::INIT] << "System directory: '"
				    << system_lyxdir_ << '\'' << endl;

	// This is true when we are running from a Mac OS X bundle
	// (for LyX/Mac)
	bool const inOSXBundle =
		system_lyxdir_ == NormalizePath(AddPath(binpath, "../Resources/")
						+ OnlyFilename(binname));
	if (inOSXBundle)
		lyxerr[Debug::INIT] << "Running from LyX/Mac bundle."
				    << endl;

	//
	// Set PATH for LyX/Mac
	// LyX/Mac is a relocatable application bundle; here we add to
	// the PATH so it can find binaries like reLyX inside its own
	// application bundle, and also append PATH elements that it
	// needs to run latex, previewers, etc.
	//

	if (inOSXBundle) {
		const string newpath = GetEnv("PATH") + ":" + binpath
			+ ":/sw/bin:/usr/local/bin"
			+ ":/usr/local/teTeX/bin/powerpc-apple-darwin-current";
		lyx::support::putenv("PATH", newpath);
		lyxerr[Debug::INIT] << "LyX/Mac: setting PATH to: "
				    << GetEnv("PATH") << endl;
	}


	//
	// Determine locale directory
	//
	if (!GetEnv("LYX_LOCALEDIR").empty()) {
		localedir_ = GetEnv("LYX_LOCALEDIR");
		lyxerr[Debug::INIT] << "LYX_LOCALEDIR=" << localedir_ << endl;
	} else if (inOSXBundle) {
		string const maybe_localedir =
			NormalizePath(AddPath(system_lyxdir_, "../locale"));
		FileInfo fi(maybe_localedir);
		if (fi.isOK() && fi.isDir()) {
			lyxerr[Debug::INIT]
				<< "LyX/Mac: setting locale directory to "
				<< maybe_localedir << endl;
			localedir_ = maybe_localedir;
		}
	}

	//
	// Determine user lyx-dir
	//

	// Directories are searched in this order:
	// 1) -userdir command line parameter
	// 2) LYX_USERDIR_14x environment variable
	// 3) $HOME/.<name of binary>

	// If we had a command line switch, user_lyxdir_ is already set
	bool explicit_userdir = true;
	if (user_lyxdir_.empty()) {

		// LYX_USERDIR_14x environment variable
		user_lyxdir_ = GetEnvPath("LYX_USERDIR_14x");

		// default behaviour
		if (user_lyxdir_.empty())
			if (inOSXBundle)
				user_lyxdir_ = AddPath(GetEnvPath("HOME"),
						       "Library/Preferences/LyX");
			else
				user_lyxdir_ = AddPath(GetEnvPath("HOME"),
						       string(".") + PACKAGE);
		explicit_userdir = false;
	}

	lyxerr[Debug::INIT] << "User LyX directory: '"
			    <<  user_lyxdir_ << '\'' << endl;
	return explicit_userdir;
}

} // namespace support
} // namespace lyx