import wx
import logging
from sld_panel import SldPanel
from sans.guicomm.events import NewPlotEvent, StatusEvent 


class Plugin:
    """
        This class defines the interface for a Plugin class
        for calculator perspective
    """
    
    def __init__(self, standalone=True):
        """
            Abstract class for gui_manager Plugins.
        """
        ## Plug-in name. It will appear on the application menu.
        self.sub_menu = "Calculator"        
        
        ## Reference to the parent window. Filled by get_panels() below.
        self.parent = None
        
        ## List of panels that you would like to open in AUI windows
        #  for your plug-in. This defines your plug-in "perspective"
        self.perspective = []
        # Log startup
        logging.info("Calculator plug-in started")   
        
    def populate_menu(self, id, owner):
        """
            Create and return the list of application menu
            items for the plug-in. 
            
            @param id: deprecated. Un-used.
            @param parent: parent window
            @return: plug-in menu
        """
        return []
      
    def get_panels(self, parent):
        """
            Create and return the list of wx.Panels for your plug-in.
            Define the plug-in perspective.
            
            Panels should inherit from DefaultPanel defined below,
            or should present the same interface. They must define
            "window_caption" and "window_name".
            
            @param parent: parent window
            @return: list of panels
        """
        ## Save a reference to the parent
        self.parent = parent
        
        # Define a panel
        self.sld_panel= SldPanel(self.parent, -1)
        
        # If needed, add its name to the perspective list
        self.perspective.append(self.sld_panel.window_name)

        # Return the list of panels
        return [self.sld_panel]
    
    def help(self, evt):
        """
            Show a general help dialog. 
            TODO: replace the text with a nice image
        """
        
        """
            provide more hint on the SLD calculator
        """
        from help_panel import  HelpWindow
        frame = HelpWindow(None, -1, pageToOpen="doc/sld_calculator_help.html")    
        frame.Show(True)
        name = "SLD_calculator"
        if frame.rhelp.HasAnchor(name):
            frame.rhelp.ScrollToAnchor(name)
        else:
           msg= "Cannot find SLD Calculator description "
           msg +="Please.Search in the Help window"
           wx.PostEvent(self.parent, StatusEvent(status = msg )) 
        
    def get_context_menu(self, graph=None):
        """
            This method is optional.
        
            When the context menu of a plot is rendered, the 
            get_context_menu method will be called to give you a 
            chance to add a menu item to the context menu.
            
            A ref to a Graph object is passed so that you can
            investigate the plot content and decide whether you
            need to add items to the context menu.  
            
            This method returns a list of menu items.
            Each item is itself a list defining the text to 
            appear in the menu, a tool-tip help text, and a
            call-back method.
            
            @param graph: the Graph object to which we attach the context menu
            @return: a list of menu items with call-back function
        """
        return []    
    
    def get_perspective(self):
        """
            Get the list of panel names for this perspective
        """
        return self.perspective
    
    def on_perspective(self, event):
        """
            Call back function for the perspective menu item.
            We notify the parent window that the perspective
            has changed.
            @param event: menu event
        """
        self.parent.set_perspective(self.perspective)
    
    def post_init(self):
        """
            Post initialization call back to close the loose ends
        """
        pass