error.py

import pygame #import everything pygame-related
from pygame.locals import *
import traceback #import traceback module to display exceptions
import time

import font #import font to show a pretty traceback
import settings

#defines a whole bunch of different exceptions for error handling

class QuitException(Exception): #exception to force a quit
    def __init__(self, message=""):
        Exception.__init__(self, message)

#exception handler routines
def exception_write(g, strin): #writes a line to exception outputs
    print strin #print it
    try:
        if g.out: g.out.write(strin+"\n") #write it to output if present
        if g.font is None: return #return if we don't need to write it to the screen
        words = strin.split(" ") #draw it nice and word-wrapped
        curr = []
        while len(words) > 0:
            curr.append(words[0]) #append current word
            if g.font.get_width(" ".join(curr))+4 > settings.screen_x: #if current line is too wide
                if g.linepos+g.font.height >= settings.screen_y: #if we've gone off the screen
                    break #stop rendering
                g.font.render(" ".join(curr[:-1]), g.surf, (2, g.linepos)) #render the line minus last word
                g.linepos += g.font.height #go to next line
                curr = [curr[-1]] #put last word as only one in buffer
            words = words[1:] #go to next word
        #once we're done, render current buffer
        if len(curr) == 0: return #return if it's empty
        #return if we've gone off the screen
        if g.linepos+g.font.height >= settings.screen_y: return
        g.font.render(" ".join(curr), g.surf, (2, g.linepos)) #render last line
        g.linepos += g.font.height #and go to next line
    except:
        pass

def exception_handler(g, e): #handles exception
    tb = traceback.format_exc() #get exception
    try: #attempt to load a font
        g.font = font.Font("fonts/selfdialog_font.xml")
        g.surf = pygame.Surface((settings.screen_x, settings.screen_y)) #and a surface to draw on
        g.surf.fill((0, 0, 100)) #fill with pretty blue
        g.linepos = 0
    except: #if there was an error loading it
        g.font = None #set font to none
    try: #attempt to open an output file
        g.out = open("exception.txt", "w")
    except: #if that couldn't be done
        g.out = None #set it to none
    #write header
    exception_write(g, "We're terribly sorry, but an internal error has occurred :(")
    t = "This will be written to the console" #only say file if file could be opened
    if g.out: t += " and a file named exception.txt in the current directory"
    exception_write(g, t+".")
    exception_write(g, "Press ESCAPE to exit (if displayed on-screen)")
    try: #attempt to make a backup save
        g.game.save("error.pokesav") #say if it could be done successfully
        exception_write(g, "Game was saved to error.pokesav.")
    except:
        exception_write(g, "Game could not be saved.")
    lines = tb.split("\n") #lines of exception
    exception_write(g, lines[-2]) #show last line of exception
    #now write out traceback
    for line in lines:
        exception_write(g, line)
    exception_write(g, "Error handler finished.")

    #now, finish display
    if g.out is not None: g.out.close() #close output file if it was opened
    if g.font is None: return #return if the font was never opened
    #otherwise, draw font and do a short event loop
    pygame.transform.scale(g.surf, (settings.screen_x*settings.screen_scale, \
        settings.screen_y*settings.screen_scale), g.screen) #draw the screen scaled properly
    pygame.display.flip() #flip double buffers
    running = True
    while running: #do a brief event loop that watches for escape key
        for event in pygame.event.get():
            if event.type == QUIT: #if we're being told to quit
                running = False #stop running
                break #and stop processing events
            elif event.type == KEYDOWN: #if a key has been pressed
                if event.key == K_ESCAPE: #and it was escape
                    running = False #stop running
                    break #and processing events
        time.sleep(0.1)