# -*- encoding: utf-8 -*-
##
## Copyright (C) 2011 Thibaut Girka <thib@sitedethib.com>
##
## This program is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published
## by the Free Software Foundation; version 3 only.
##
## This program is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
## GNU General Public License for more details.
##


from pytouhou.utils.interpolator import Interpolator
from pytouhou.vm.anmrunner import ANMRunner
from pytouhou.game.sprite import Sprite
from pytouhou.game.bullet import Bullet
from math import cos, sin, atan2, pi


class Enemy(object):
    def __init__(self, pos, life, _type, bonus_dropped, die_score, anm_wrapper, game):
        self._game = game
        self._anm_wrapper = anm_wrapper
        self._sprite = None
        self._anmrunner = None
        self._removed = False
        self._visible = True
        self._type = _type
        self._bonus_dropped = bonus_dropped
        self._die_score = die_score #TODO: use it
        self._was_visible = False

        self.frame = 0

        self.x, self.y = pos
        self.life = 1 if life < 0 else life
        self.max_life = life
        self.touchable = True
        self.collidable = True
        self.damageable = True
        self.death_flags = 0
        self.boss = False
        self.difficulty_coeffs = (-.5, .5, 0, 0, 0, 0)
        self.extended_bullet_attributes = (0, 0, 0, 0, 0., 0., 0., 0.)
        self.bullet_attributes = None
        self.bullet_launch_offset = (0, 0)
        self.death_callback = None
        self.boss_callback = None
        self.low_life_callback = None
        self.low_life_trigger = None
        self.timeout = None
        self.timeout_callback = None
        self.remaining_lives = -1

        self.automatic_orientation = False

        self.bullet_launch_interval = 0
        self.bullet_launch_timer = 0
        self.delay_attack = False

        self.death_anim = 0
        self.movement_dependant_sprites = None
        self.direction = None
        self.interpolator = None #TODO
        self.speed_interpolator = None
        self.angle = 0.
        self.speed = 0.
        self.rotation_speed = 0.
        self.acceleration = 0.

        self.hitbox = (0, 0)
        self.hitbox_half_size = (0, 0)
        self.screen_box = None


    def set_bullet_attributes(self, type_, anim, sprite_idx_offset,
                              bullets_per_shot, number_of_shots, speed, speed2,
                              launch_angle, angle, flags):

        # Apply difficulty-specific modifiers
        speed_a, speed_b, nb_a, nb_b, shots_a, shots_b = self.difficulty_coeffs
        diff_coeff = self._game.difficulty / 32.

        speed += speed_a * (1. - diff_coeff) + speed_b * diff_coeff
        speed2 += (speed_a * (1. - diff_coeff) + speed_b * diff_coeff) / 2.
        bullets_per_shot += int(nb_a * (1. - diff_coeff) + nb_b * diff_coeff)
        number_of_shots += int(shots_a * (1. - diff_coeff) + shots_b * diff_coeff)

        self.bullet_attributes = (type_, anim, sprite_idx_offset, bullets_per_shot,
                                  number_of_shots, speed, speed2, launch_angle,
                                  angle, flags)
        if not self.delay_attack:
            self.fire()


    def set_bullet_launch_interval(self, value, start=0.):
        # Apply difficulty-specific modifiers:
        value *= 1. - .4 * (self._game.difficulty - 16.) / 32.

        self.bullet_launch_interval = int(value)
        self.bullet_launch_timer = int(value * start)


    def fire(self, offset=None, bullet_attributes=None, launch_pos=None):
        (type_, type_idx, sprite_idx_offset, bullets_per_shot, number_of_shots,
         speed, speed2, launch_angle, angle, flags) = bullet_attributes or self.bullet_attributes

        bullet_type = self._game.bullet_types[type_idx]

        if not launch_pos:
            ox, oy = offset or self.bullet_launch_offset
            launch_pos = self.x + ox, self.y + oy

        if speed2 < 0.3:
            speed2 = 0.3

        self.bullet_launch_timer = 0

        player = self.select_player()

        if type_ in (67, 69, 71):
            launch_angle += self.get_player_angle(player, launch_pos)
        if type_ in (69, 70, 71, 74):
            angle = 2. * pi / bullets_per_shot
        if type_ == 71:
            launch_angle += pi / bullets_per_shot
        if type_ != 75:
            launch_angle -= angle * (bullets_per_shot - 1) / 2.

        bullets = self._game.bullets
        nb_bullets_max = self._game.nb_bullets_max

        for shot_nb in range(number_of_shots):
            shot_speed = speed if shot_nb == 0 else speed + (speed2 - speed) * float(shot_nb) / float(number_of_shots)
            bullet_angle = launch_angle
            for bullet_nb in range(bullets_per_shot):
                if nb_bullets_max is not None and len(bullets) == nb_bullets_max:
                    break

                if type_ == 75: # 102h.exe@0x4138cf
                    bullet_angle = self._game.prng.rand_double() * (launch_angle - angle) + angle
                if type_ in (74, 75): # 102h.exe@0x4138cf
                    shot_speed = self._game.prng.rand_double() * (speed - speed2) + speed2
                bullets.append(Bullet(launch_pos, bullet_type, sprite_idx_offset,
                                      bullet_angle, shot_speed,
                                      self.extended_bullet_attributes,
                                      flags, player, self._game))
                bullet_angle += angle


    def select_player(self, players=None):
        return min(players or self._game.players, key=lambda p: ((p.x - self.x) ** 2 + (p.y - self.y) ** 2, p.state.character)) #TODO


    def get_player_angle(self, player=None, pos=None):
        player = player or self.select_player()
        x, y = pos or (self.x, self.y)
        return atan2(player.y - y, player.x - x)


    def set_anim(self, index):
        self._sprite = Sprite()
        self._anmrunner = ANMRunner(self._anm_wrapper, index, self._sprite)
        self._anmrunner.run_frame()


    def die_anim(self):
        self._game.new_death((self.x, self.y), self.death_anim)


    def drop_particles(self, number, color):
        #TODO: white particles are only used in stage 3 to 6,
        # in other stages they are blue.
        if color == 0:
            if self._game.stage in [1, 2, 7]:
                color = 3
        for i in range(number):
            self._game.new_particle((self.x, self.y), color, 4., 256) #TODO: find the real size.


    def set_pos(self, x, y, z):
        self.x, self.y = x, y
        self.interpolator = Interpolator((x, y))
        self.interpolator.set_interpolation_start(self._game.frame, (x, y))


    def move_to(self, duration, x, y, z, formula):
        if not self.interpolator:
            frame = self._game.frame
            self.interpolator = Interpolator((self.x, self.y), formula)
            self.interpolator.set_interpolation_start(frame, (self.x, self.y))
            self.interpolator.set_interpolation_end(frame + duration - 1, (x, y))

            self.speed = 0.
            self.angle = atan2(y - self.y, x - self.x)


    def stop_in(self, duration, formula):
        if not self.speed_interpolator:
            frame = self._game.frame
            self.speed_interpolator = Interpolator((self.speed,), formula)
            self.speed_interpolator.set_interpolation_start(frame, (self.speed,))
            self.speed_interpolator.set_interpolation_end(frame + duration - 1, (0.,))

            self.speed = 0.


    def is_visible(self, screen_width, screen_height):
        if self._sprite:
            tx, ty, tw, th = self._sprite.texcoords
            if self._sprite.corner_relative_placement:
                raise Exception #TODO
        else:
            tx, ty, tw, th = 0., 0., 0., 0.

        x, y = self.x, self.y
        max_x = tw / 2.
        max_y = th / 2.

        if (max_x < x - screen_width
            or max_x < -x
            or max_y < y - screen_height
            or max_y < -y):
            return False
        return True


    def check_collisions(self):
        # Check for collisions
        ex, ey = self.x, self.y
        ehalf_size_x, ehalf_size_y = self.hitbox_half_size
        ex1, ex2 = ex - ehalf_size_x, ex + ehalf_size_x
        ey1, ey2 = ey - ehalf_size_y, ey + ehalf_size_y

        damages = 0

        # Check for enemy-bullet collisions
        for bullet in self._game.players_bullets:
            half_size = bullet.hitbox_half_size
            bx, by = bullet.x, bullet.y
            bx1, bx2 = bx - half_size[0], bx + half_size[0]
            by1, by2 = by - half_size[1], by + half_size[1]

            if not (bx2 < ex1 or bx1 > ex2
                    or by2 < ey1 or by1 > ey2):
                bullet.collide()
                damages += bullet.damage
                self.drop_particles(1, 1)

        # Check for enemy-player collisions
        ex1, ex2 = ex - ehalf_size_x * 2. / 3., ex + ehalf_size_x * 2. / 3.
        ey1, ey2 = ey - ehalf_size_y * 2. / 3., ey + ehalf_size_y * 2. / 3.
        if self.collidable:
            for player in self._game.players:
                px, py = player.x, player.y
                phalf_size = player.hitbox_half_size
                px1, px2 = px - phalf_size, px + phalf_size
                py1, py2 = py - phalf_size, py + phalf_size

                #TODO: box-box or point-in-box?
                if not (ex2 < px1 or ex1 > px2 or ey2 < py1 or ey1 > py2):
                    if not self.boss:
                        damages += 10
                    player.collide()

        # Adjust damages
        damages = min(70, damages)
        score = (damages // 5) * 10 #TODO: give to which player?

        if self._game.spellcard:
            #TODO: there is a division by 3, somewhere... where is it?
            if damages <= 7:
                damages = 1 if damages else 0
            else:
                damages //= 7

        # Apply damages
        if self.damageable:
            self.life -= damages


    def update(self):
        x, y = self.x, self.y
        if self.interpolator:
            self.interpolator.update(self._game.frame)
            x, y = self.interpolator.values

        self.speed += self.acceleration #TODO: units? Execution order?
        self.angle += self.rotation_speed #TODO: units? Execution order?


        if self.speed_interpolator:
            self.speed_interpolator.update(self._game.frame)
            self.speed, = self.speed_interpolator.values


        dx, dy = cos(self.angle) * self.speed, sin(self.angle) * self.speed
        if self._type & 2:
            x -= dx
        else:
            x += dx
        y += dy

        if self.movement_dependant_sprites:
            #TODO: is that really how it works? Almost.
            # Sprite determination is done only once per changement, and is
            # superseeded by ins_97.
            end_left, end_right, left, right = self.movement_dependant_sprites
            if x < self.x and self.direction != -1:
                self.set_anim(left)
                self.direction = -1
            elif x > self.x and self.direction != +1:
                self.set_anim(right)
                self.direction = +1
            elif x == self.x and self.direction is not None:
                self.set_anim({-1: end_left, +1: end_right}[self.direction])
                self.direction = None


        if self.screen_box:
            xmin, ymin, xmax, ymax = self.screen_box
            x = max(xmin, min(x, xmax))
            y = max(ymin, min(y, ymax))


        self.x, self.y = x, y

        #TODO
        if self._anmrunner and not self._anmrunner.run_frame():
            self._anmrunner = None

        if self._sprite and self._visible:
            if self._sprite._removed:
                self._sprite = None
            else:
                self._sprite.update_orientation(self.angle,
                                                self.automatic_orientation)


        if self.bullet_launch_interval != 0:
            self.bullet_launch_timer += 1
            if self.bullet_launch_timer == self.bullet_launch_interval:
                self.fire()

        # Check collisions
        if self.touchable:
            self.check_collisions()

        self.frame += 1