import wx
import eos.db
import gui.mainFrame
from gui import globalEvents as GE
from .calc.fitAddModule import FitAddModuleCommand
from .calc.fitReplaceModule import FitReplaceModuleCommand
from .calc.fitSetCharge import FitSetChargeCommand
from service.fit import Fit


class GuiModuleAddCommand(wx.Command):
    def __init__(self, fitID, itemID, position=None):
        """
        Handles adding an item, usually a module, to the Fitting Window.

        :param fitID: The fit ID that we are modifying
        :param itemID: The item that is to be added to the Fitting View. If this turns out to be a charge, we attempt to
                       set the charge on the underlying module (requires position)
        :param position: Optional. The position in fit.modules that we are attempting to set the item to
        """
        wx.Command.__init__(self, True, "Module Add: {}".format(itemID))
        self.mainFrame = gui.mainFrame.MainFrame.getInstance()
        self.sFit = Fit.getInstance()
        self.fitID = fitID
        self.itemID = itemID
        self.internal_history = wx.CommandProcessor()
        self.position = position
        self.old_mod = None

    def Do(self):
        success = False
        item = eos.db.getItem(self.itemID)
        if item.isCharge and self.position is not None:
            success = self.internal_history.Submit(FitSetChargeCommand(self.fitID, [self.position], self.itemID))
            if not success:
                return False  # if it's a charge item and this failed, nothing more we can try.
        # if we have a position set, try to apply the module to that position
        elif self.position is not None:
            success = self.internal_history.Submit(FitReplaceModuleCommand(self.fitID, self.position, self.itemID))
            if not success:
                # something went wrong with trying to fit the module into specific location, attempt to append it
                self.position = None

        # if we're not trying to set module to a position, simply append
        if self.position is None:
            success = self.internal_history.Submit(FitAddModuleCommand(self.fitID, self.itemID))

        if success:
            self.sFit.recalc(self.fitID)
            wx.PostEvent(self.mainFrame, GE.FitChanged(fitID=self.fitID, action="modadd", typeID=self.itemID))
            return True
        return False


    def Undo(self):
        for _ in self.internal_history.Commands:
            self.internal_history.Undo()
        self.sFit.recalc(self.fitID)
        wx.PostEvent(self.mainFrame, GE.FitChanged(fitID=self.fitID, action="moddel", typeID=self.itemID))
        return True