# Made this program before I got out of my import * habit
from tkinter import *

class SaveAsWindow:
    '''Simple window, enter filename, and press save to export the canvas as a post script file viewable in acrobat'''
    def remove_window(self):
        '''Destroys the window'''
        self.parent.saving = False
        self.save_window.destroy()

    def save(self):
        '''Saves the cavas as a ps file'''
        self.file_name = self.entry.get()
        save_file = self.parent.canvas.postscript(file = self.file_name + ".ps")
        self.parent.saving = False
        self.save_window.destroy()

    def __init__(self, parent):
        '''Creates the window'''
        self.parent = parent
        if parent.saving == False:
            parent.saving = True
            self.save_window = Tk()
            self.save_window.title("Save as...")
            self.file_name = ""

            self.entry = Entry(self.save_window)
            self.save_button = Button(self.save_window, text = "save", command = self.save)

            self.entry.grid(column = 0, row = 0)
            self.save_button.grid(column = 1, row = 0)

            self.save_window.protocol("WM_DELETE_WINDOW", self.remove_window)

class Palate:
    '''A window containing a grid of buttons to change the brush color'''
    def remove_palate(self):
        '''Destroys the window'''
        self.parent.palate = False
        self.color_grid.destroy()

    def __init__(self, parent):
        '''Creates the window'''
        self.parent = parent
        if parent.palate == False:
            parent.palate = True

            self.color_grid = Tk()

            self.black_button = Button(self.color_grid, bg="black", width = 3, command = lambda: self.parent.set_color("black"))
            self.red_button = Button(self.color_grid, bg="red", width = 3, command = lambda: self.parent.set_color("red"))
            self.blue_button = Button(self.color_grid, bg="blue", width = 3, command = lambda: self.parent.set_color("blue"))
            self.green_button = Button(self.color_grid, bg="green", width = 3, command = lambda: self.parent.set_color("green"))
            self.purple_button = Button(self.color_grid, bg="purple", width = 3, command = lambda: self.parent.set_color("purple"))
            self.yellow_button = Button(self.color_grid, bg="yellow", width = 3, command = lambda: self.parent.set_color("yellow"))
            self.orange_button = Button(self.color_grid, bg="orange", width = 3, command = lambda: self.parent.set_color("orange"))
            self.hot_pink_button = Button(self.color_grid, bg="hot pink", width = 3, command = lambda: self.parent.set_color("hot pink"))
            self.teal_button = Button(self.color_grid, bg="teal", width = 3, command = lambda: self.parent.set_color("teal"))
            self.brown_button = Button(self.color_grid, bg="saddle brown", width = 3, command = lambda: self.parent.set_color("brown"))
            self.grey_button = Button(self.color_grid, bg="dark grey", width = 3, command = lambda: self.parent.set_color("dark grey"))
            self.lgreen_button = Button(self.color_grid, bg="lime green", width = 3, command = lambda: self.parent.set_color("lime green"))
            self.sblue_button = Button(self.color_grid, bg="sky blue", width = 3, command = lambda: self.parent.set_color("sky blue"))
            self.tan_button = Button(self.color_grid, bg="tan", width = 3, command = lambda: self.parent.set_color("tan"))
            self.ygreen_button = Button(self.color_grid, bg="yellow green", width = 3, command = lambda: self.parent.set_color("yellow green"))
            self.white_button = Button(self.color_grid, bg="white", width = 3, command = lambda: self.parent.set_color("white"))

            self.black_button.grid(row = 0, column = 0)
            self.red_button.grid(row = 0, column = 1)
            self.blue_button.grid(row = 0, column = 2)
            self.teal_button.grid(row = 0, column = 3)
            self.green_button.grid(row = 1, column = 0)
            self.purple_button.grid(row = 1, column = 1)
            self.yellow_button.grid(row = 1, column = 2)
            self.brown_button.grid(row = 1, column = 3)
            self.orange_button.grid(row = 2, column = 0)
            self.hot_pink_button.grid(row = 2, column = 1)
            self.white_button.grid(row = 2, column = 2)
            self.grey_button.grid(row = 2, column = 3)
            self.lgreen_button.grid(row = 3, column = 0)
            self.sblue_button.grid(row = 3, column = 1)
            self.tan_button.grid(row = 3, column = 2)
            self.ygreen_button.grid(row = 3, column = 3)

            self.color_grid.protocol("WM_DELETE_WINDOW", self.remove_palate)

class MainWindow:
    def close_all(self):
        '''Closes all windows'''
        if self.palate:
            self.palate_window.remove_palate()
        if self.saving:
            self.save_window.remove_window()

        self.root.destroy()

    def set_color(self, new_color):
        '''Sets the brush color to the chosen color'''
        self.color = new_color

    def reduce_size(self):
        '''Reduces the brush size by 2 if possible'''
        if self.size > 2:
            self.size -= 2
            self.size_text.set(self.size)

    def increase_size(self):
        '''Increases the brush size by 2'''
        self.size += 2
        self.size_text.set(str(self.size))

    def set_size(self, int_size):
        '''Sets the brush to the requested size'''
        self.size = int_size
        self.size_text.set(str(int_size))

    def enable_draw(self, event):
        '''Sets up the necessary variables to begin drawing on the canvas'''
        size = self.size
        x, y = event.x, event.y
        self.last_x, self.last_y = x, y
        self.brush_down = True
        self.actions.append(self.canvas.create_oval(x-(size/2), y-(size/2), x+(size/2), y+(size/2), outline = self.color, fill = self.color))

    def disable_draw(self, event):
        '''Disables canvas drawing'''
        self.brush_down = False

    def update(self, event):
        '''If you are not drawing, display the cursor, otherwise, draw a line from the last x,y to the new x,y'''
        size = self.size
        x, y = event.x, event.y
        try:
            self.canvas.delete(self.cursor)
        finally:
            if not self.brush_down:
                if self.color != "white":
                    self.cursor = self.canvas.create_oval(x-(size/2), y-(size/2), x+(size/2), y+(size/2), outline = self.color)
                else:
                    self.cursor = self.canvas.create_oval(x-(size/2), y-(size/2), x+(size/2), y+(size/2), outline = "black")
            else:
                self.actions.append(self.canvas.create_line(x, y, self.last_x, self.last_y, width=size, fill = self.color))
                self.actions.append(self.canvas.create_oval(x-(size/2), y-(size/2), x+(size/2), y+(size/2), outline = self.color, fill = self.color))
                self.last_x, self.last_y = x, y

    def remove_cursor(self, event):
        '''Remove the cursor'''
        self.canvas.delete(self.cursor)

    def clear_canvas(self, event):
        '''Clear all drawn objects on the canvas'''
        self.canvas.delete(ALL)

    def save_window(self, event):
        '''Create the save window'''
        self.save_window = SaveAsWindow(self)

    def create_palate(self, event):
        '''Create the palate window'''
        self.palate_window = Palate(self)

    def check_brush_empty(self):
        '''Checks if the user failed to input a new size'''
        num = self.size_display.get()
        if num == "":
            self.size_text.set(self.size)

    def check_brush_change(self, event):
        '''Checks if the user input a size that is invalid'''
        num = self.size_display.get()
        if num != "":
            try:
                num = int(num)
                if num >= 1:
                    self.set_size(num)
                else:
                    self.size_text.set(size)
            except:
                self.size_text.set(size)
        else:
            self.root.after(2000, check_brush_empty)

    def __init__(self):
        '''Sets up the window'''
        self.root = Tk()
        self.color = "black"
        self.size = 10
        self.size_text = StringVar()
        self.size_text.set(self.size)
        self.brush_down = False
        self.palate = False
        self.saving = False
        self.actions = []
        self.cursor = 0
        self.last_x, self.last_y = 0, 0

        self.palate_button = Button(self.root, text = "Create Palate", fg = "blue")
        self.clear_button = Button(self.root, text = "Clear")
        self.save_button = Button(self.root, text = "Save")
        self.minus_size = Button(self.root, text = "<", command = self.reduce_size, width = 15)
        self.size_display = Entry(self.root, textvariable = self.size_text, justify = CENTER)
        self.add_size = Button(self.root, text = ">", command = self.increase_size, width = 15)
        self.reset_size = Button(self.root, text = "Reset Brush", command = lambda: self.set_size(10))
        self.canvas = Canvas(self.root, bg = "white", height = 500, width = 500, cursor="none")

        self.clear_button.grid(row = 0, column = 0, sticky = W+E)
        self.save_button.grid(row = 0, column = 1, sticky = W+E)
        self.palate_button.grid(row = 1, column = 0, sticky = W+E)
        self.minus_size.grid(row = 1, column = 2, sticky = W)
        self.size_display.grid(row = 1, column = 3, sticky = E+W)
        self.add_size.grid(row = 1, column = 4, sticky = E)
        self.reset_size.grid(row=0, column = 2, columnspan = 3, sticky = W+E)
        self.canvas.grid(row = 2, column = 0, columnspan = 5, sticky = W+E)

        self.canvas.bind('<Motion>', self.update)
        self.canvas.bind('<ButtonPress-1>', self.enable_draw)
        self.canvas.bind('<ButtonRelease-1>', self.disable_draw)
        self.canvas.bind('<Leave>', self.remove_cursor)
        self.clear_button.bind('<Button-1>', self.clear_canvas)
        self.save_button.bind('<Button-1>', self.save_window)
        self.palate_button.bind('<Button-1>', self.create_palate)
        self.size_display.bind('<KeyRelease>', self.check_brush_change)

        self.root.protocol("WM_DELETE_WINDOW", self.close_all)

app = MainWindow()