#include <cassert>
#include <cstring>
#include <cstdlib>
#include <unistd.h>
#include "FrameUtil/AbsInterp.hh"
#include "TclUtils/TclInterpManager.hh"

TclInterpManager* TclInterpManager::_instance = 0;

TclInterpManager::TclInterpManager() :
    _defaultShared(true),
    _lastDeletedInterp(0)
{
    _sharedInterp = Tcl_CreateInterp();
    _initialize(_sharedInterp);

    // Install the "ac++" command into AbsInterp
    char command[] = "proc ac++ {args} {catch {uplevel #0 $args} result ; if {[string length $result] > 0} {puts $result ; flush stdout} ; return}";
    AbsInterp::instance()->simulateInput(std::string(command));
}

TclInterpManager* TclInterpManager::instance()
{
    if (_instance == 0)
	_instance = new TclInterpManager;
    return _instance;
}

Tcl_Interp * TclInterpManager::getInterp()
{
    return getInterp(_defaultShared);
}

void TclInterpManager::setShared(bool trueOrFalse)
{
    _defaultShared = trueOrFalse;
}

bool TclInterpManager::isShared()
{
    return _defaultShared;
}

Tcl_Interp * TclInterpManager::getInterp(bool isShared)
{
    if (isShared)
    {
	return _sharedInterp;
    }
    else
    {
	Tcl_Interp *interp = Tcl_CreateInterp();
	_initialize(interp);
	return interp;
    }
}

void TclInterpManager::deleteInterp(Tcl_Interp *interp)
{
    assert(interp);
    // Delayed deletion. Useful for classes which have Tcl
    // interpreters as members, e.g. TclModule.
    if (interp != _sharedInterp)
    {
        if (_lastDeletedInterp != interp)
        {
            if (_lastDeletedInterp)
                Tcl_DeleteInterp(_lastDeletedInterp);
            _lastDeletedInterp = interp;
        }
    }
}

void TclInterpManager::_initialize(Tcl_Interp *interp)
{
    Tcl_Init(interp);
    Tcl_SetVar(interp, "tcl_interactive",
	       const_cast<char*>(isatty(0) ? "1" : "0"), TCL_GLOBAL_ONLY);

    // Install the "ac++" command
    char command[] = "ac++";
    Tcl_CreateCommand(interp, command,
	  reinterpret_cast<Tcl_CmdProc *>(_absInterpCommand), 0, 0);

    // Source the Tcl utility script
    char sourceutils[] = "set inifile_u $env(CDFSOFT2_DIR)/TclUtils/scripts/TclUtils.tcl\n"
	"if {[info exists env(SRT_LOCAL)]} {\n"
	"if {[string compare $env(SRT_LOCAL) \".\"]} {\n"
	"if {[file readable $env(SRT_LOCAL)/TclUtils/scripts/TclUtils.tcl]} {\n"
	"set inifile_u $env(SRT_LOCAL)/TclUtils/scripts/TclUtils.tcl\n"
	"}\n"
	"}\n"
	"}\n"
	"catch {source $inifile_u}\n"
	"unset inifile_u";
    Tcl_GlobalEval(interp, sourceutils);

    // Reset the interpreter result
    Tcl_ResetResult(interp);
}

int TclInterpManager::_absInterpCommand(ClientData clientData,
					Tcl_Interp *interp,
					int argc, char *argv[])
{
    if (argc < 2)
    {
	Tcl_SetResult(interp, "wrong # of arguments", TCL_VOLATILE);
	return TCL_ERROR;
    }
    char *script = Tcl_Concat(argc, argv);
    AbsInterp::instance()->simulateInput(std::string(script));
    Tcl_Free(script);
    return TCL_OK;
}