# Copyright 2004-2021 Tom Rothamel <pytom@bishoujo.us>
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation files
# (the "Software"), to deal in the Software without restriction,
# including without limitation the rights to use, copy, modify, merge,
# publish, distribute, sublicense, and/or sell copies of the Software,
# and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

from __future__ import division, absolute_import, with_statement, print_function, unicode_literals

import json
import renpy


class Linear(object):

    def __init__(self, x0, y0, x1, y1):
        self.duration = x1 - x0

        self.y0 = y0
        self.y1 = y1

    def get(self, t):
        done = t / self.duration
        return self.y0 + (self.y1 - self.y0) * done

    def wait(self, t):
        return 0


class Step(object):

    def __init__(self, x0, y0, x1, y1):
        self.duration = x1 - x0

        self.y0 = y0
        self.y1 = y1

    def get(self, t):
        return self.y0

    def wait(self, t):
        return max(self.duration - t, 0.0)


class InvStep(object):

    def __init__(self, x0, y0, x1, y1):
        self.duration = x1 - x0

        self.y0 = y0
        self.y1 = y1

    def get(self, t):
        return self.y1

    def wait(self, t):
        return max(self.duration - t, 0.0)


class Bezier(object):

    def __init__(self, x0, y0, x1, y1, x2, y2, x3, y3):
        self.duration = x3 - x0

        self.x0 = 0
        self.x1 = x1 - x0
        self.x2 = x2 - x0
        self.x3 = x3 - x0

        self.y0 = y0
        self.y1 = y1
        self.y2 = y2
        self.y3 = y3

    def get(self, t):
        done = t / self.duration

        def lerp(a, b):
            return a + (b - a) * done

        p01 = lerp(self.y0, self.y1)
        p12 = lerp(self.y1, self.y2)
        p23 = lerp(self.y2, self.y3)

        p012 = lerp(p01, p12)
        p123 = lerp(p12, p23)

        return lerp(p012, p123)

    def wait(self, t):
        return 0


class Motion(object):

    def __init__(self, filename, fadein, fadeout):

        self.filename = filename

        with renpy.loader.load(filename) as f:
            j = json.load(f)

        self.duration = j["Meta"]["Duration"]
        self.curves = { }
        self.fades = { }

        for curve in j["Curves"]:
            target = curve["Target"]
            name = curve["Id"]
            s = curve["Segments"]

            x0 = s.pop(0)
            y0 = s.pop(0)

            segments = [ ]

            while s:

                kind = s.pop(0)

                if kind == 0:
                    x = s.pop(0)
                    y = s.pop(0)

                    segments.append(Linear(x0, y0, x, y))

                elif kind == 1:
                    x1 = s.pop(0)
                    y1 = s.pop(0)
                    x2 = s.pop(0)
                    y2 = s.pop(0)
                    x = s.pop(0)
                    y = s.pop(0)

                    segments.append(Bezier(x0, y0, x1, y1, x2, y2, x, y))

                elif kind == 2:
                    x = s.pop(0)
                    y = s.pop(0)

                    segments.append(Step(x0, y0, x, y))

                elif kind == 3:
                    x = s.pop(0)
                    y = s.pop(0)

                    segments.append(InvStep(x0, y0, x, y))

                else:
                    raise Exception("Unknown kind.")

                x0 = x
                y0 = y

            self.curves[target, name] = segments
            self.fades[target, name] = (
                curve.get("FadeInTime", fadein),
                curve.get("FadeOutTime", fadeout),
                )

    def update(self, st, fade_st, do_fade_in, do_fade_out):
        """
        Returns a tuple of dictionary where the keys are the type of parameter
        and the parameter name, and the values are the blend factor and value, and
        number how much time should pass until this displayable needs to be redrawn.
        """

        if st == self.duration:
            st = self.duration
        else:
            st = st % self.duration

        data = { }

        wait = 86400.0

        for k, segments in self.curves.items():

            fadein, fadeout = self.fades[k]

            if not do_fade_in:
                fadein = 0.0

            if not do_fade_out:
                fadeout = 0.0

            factor = 1.0

            if st < fadein:
                factor = min(factor, st / fadein)

            if st > self.duration - fadeout:
                factor = min(factor, 1.0 - (st - (self.duration - fadeout)) / fadeout)

            if fade_st is not None:
                if fadeout > 0:
                    factor = min(factor, 1.0 - fade_st / fadeout)
                else:
                    factor = 0.0

            factor = max(factor, 0.0)

            t = st

            for i in segments:
                if t <= i.duration or i is segments[-1]:

                    if factor > 0.0:
                        wait = min(wait, i.wait(t))

                    data[k] = (factor, i.get(t))

                    break

                t -= i.duration

        if wait == 86400.0:
            wait = None

        return data, wait


class NullMotion(object):
    """
    A motion that is added by default,
    """

    duration = 1.0

    def update(self, st, fade_st, do_fade_in, do_fade_out):
        return { }, max(1.0 - st, 0)
