"""Animation Loops"""

from pgu.vid import Sprite

import imagecache
from misc import Position

class Animation(Sprite):
    """Animation loop.

       These are derived from sprites, since they behave similiary in most
       respects, but, to ensure draw ordering, we don't add them to
       the sprites list.
       
       Ideally, animations should be quite short."""
       # In the current implementation, sequences longer than 4 frames
       # will cause issues as this will overrun the next move loop.
       # (assuming all animations are triggered by the move loop, of course)

    def __init__(self, tv, tile_pos, sequence=None, layer='animations'):
        # Create the first frame
        if sequence is None:
            sequence = self.SEQUENCE
        self.iter = iter(sequence)
        self.layer = layer
        Sprite.__init__(self, self.iter.next(), tv.tile_to_view(tile_pos))
        tv.sprites.append(self, layer=self.layer)

    def loop(self, tv, s):
        """Step to the next frame, removing sprite when done."""
        try:
            self.setimage(self.iter.next())
        except StopIteration:
            tv.sprites.remove(self, layer=self.layer)

class MuzzleFlash(Animation):

    FLASH_LEFT = imagecache.load_image('sprites/muzzle_flash.png')
    FLASH_RIGHT = imagecache.load_image('sprites/muzzle_flash.png',
            ("right_facing",))

    SEQUENCE_LEFT = [FLASH_LEFT, FLASH_LEFT]
    SEQUENCE_RIGHT = [FLASH_RIGHT, FLASH_RIGHT]

    def __init__(self, tv, chicken, layer='animations'):
        if chicken.facing == 'right':
            Animation.__init__(self, tv, chicken.pos.to_tuple(), self.SEQUENCE_RIGHT, layer=layer)
        else:
            Animation.__init__(self, tv, chicken.pos.to_tuple(), self.SEQUENCE_LEFT, layer=layer)

class FenceExplosion(Animation):
    FLASH_1 = imagecache.load_image('sprites/boom1.png')
    FLASH_2 = imagecache.load_image('sprites/boom2.png')
    FLASH_3 = imagecache.load_image('sprites/boom3.png')
    FLASH_4 = imagecache.load_image('sprites/boom4.png')
    SEQUENCE = [FLASH_1, FLASH_2, FLASH_3, FLASH_4]

class FoxDeath(Animation):
    BLOOD_SPLAT = imagecache.load_image('sprites/fox_death.png')
    SEQUENCE = [BLOOD_SPLAT, BLOOD_SPLAT]
    
class ChickenDeath(Animation):
    BLOOD_SPLAT = imagecache.load_image('sprites/fox_death.png')
    FEATHER_SPLAT = imagecache.load_image('sprites/chkn_death.png')
    SEQUENCE = [BLOOD_SPLAT, FEATHER_SPLAT, FEATHER_SPLAT]