#
# Copyright (C) 2016-2020 by Nathan Lovato, Daniel Oakey, Razvan Radulescu, and contributors
#
# This file is part of Power Sequencer.
#
# Power Sequencer 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, either version 3 of the
# License, or (at your option) any later version.
#
# Power Sequencer 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.
#
# You should have received a copy of the GNU General Public License along with Power Sequencer. If
# not, see <https://www.gnu.org/licenses/>.
#
import bpy

from .utils.functions import get_frame_range
from .utils.functions import set_preview_range
from .utils.functions import convert_duration_to_frames
from .utils.doc import doc_name, doc_idname, doc_brief, doc_description


class POWER_SEQUENCER_OT_preview_closest_cut(bpy.types.Operator):
    """
    *brief* Toggle preview around the closest cut, based on time cursor


    Finds the closest cut to the time cursor and sets the preview to a small range around that
    frame. If the preview matches the range, resets to the full timeline
    """

    doc = {
        "name": doc_name(__qualname__),
        "demo": "",
        "description": doc_description(__doc__),
        "shortcuts": [({"type": "P", "value": "PRESS", "shift": True}, {}, "Preview Last Cut")],
        "keymap": "Sequencer",
    }
    bl_idname = doc_idname(__qualname__)
    bl_label = doc["name"]
    bl_description = doc_brief(doc["description"])
    bl_options = {"REGISTER", "UNDO"}

    duration: bpy.props.FloatProperty(
        name="Preview duration",
        description="Total duration of the preview, in seconds",
        default=1.0,
        min=0.1,
    )
    cut_frame_override: bpy.props.IntProperty(
        name="Cut Frame Override",
        description="Force to preview around this frame",
        default=0,
        min=0,
        options={"HIDDEN"},
    )

    @classmethod
    def poll(cls, context):
        return context.sequences

    def execute(self, context):
        scene = context.scene

        preview_center = (
            self.find_closest_cut_frame(context)
            if not self.cut_frame_override
            else self.cut_frame_override
        )

        duration_frame = convert_duration_to_frames(context, self.duration)
        start = preview_center - duration_frame / 2
        end = preview_center + duration_frame / 2
        if not (preview_center > 1 and start > 1):
            return {"CANCELLED"}

        if scene.frame_preview_start == start and scene.frame_preview_end == end:
            start, end = get_frame_range(context.sequences)
        set_preview_range(context, start, end)
        return {"FINISHED"}

    def find_closest_cut_frame(self, context):
        last_distance = 100000
        closest_cut_frame = 0
        for s in context.sequences:
            cuts = [s.frame_final_start, s.frame_final_end]
            for cut_frame in cuts:
                distance_to_cut = abs(cut_frame - context.scene.frame_current)
                if distance_to_cut < last_distance:
                    last_distance = distance_to_cut
                    closest_cut_frame = cut_frame
        return closest_cut_frame
