from qtpy.QtWidgets import QUndoCommand

import logging
from copy import copy
from qtpy.QtCore import QPointF

from .canvas.flowgraph import FlowgraphScene
from .canvas.block import Block
from ...core.base import Element

log = logging.getLogger(f"grc.application.{__name__}")


# Movement, rotation, enable/disable/bypass, bus ports,
# change params, toggle type.
# Basically anything that's not cut/paste or new/delete
class ChangeStateAction(QUndoCommand):
    def __init__(self, scene: FlowgraphScene):
        QUndoCommand.__init__(self)
        log.debug("init ChangeState")
        self.old_states = []
        self.old_params = []
        self.new_states = []
        self.new_params = []
        self.scene = scene
        self.g_blocks = scene.selected_blocks()
        for g_block in self.g_blocks:
            self.old_states.append(copy(g_block.core.states))
            self.new_states.append(copy(g_block.core.states))
            self.old_params.append(copy(g_block.core.params))
            self.new_params.append(copy(g_block.core.params))

    def redo(self):
        for i in range(len(self.g_blocks)):
            self.g_blocks[i].set_states(self.new_states[i])
            self.g_blocks[i].core.params = (self.new_params[i])
        self.scene.update()

    def undo(self):
        for i in range(len(self.g_blocks)):
            self.g_blocks[i].set_states(self.old_states[i])
            self.g_blocks[i].params = (self.old_params[i])
        self.scene.update()


class RotateAction(QUndoCommand):
    def __init__(self, scene: FlowgraphScene, delta_angle: int):
        QUndoCommand.__init__(self)
        log.debug("init RotateAction")
        self.setText('Rotate')
        self.g_blocks = scene.selected_blocks()
        self.scene = scene
        self.delta_angle = delta_angle

    def redo(self):
        self.scene.rotate_selected(self.delta_angle)

    def undo(self):
        self.scene.rotate_selected(-self.delta_angle)


class MoveAction(QUndoCommand):
    def __init__(self, scene: FlowgraphScene, diff: QPointF):
        QUndoCommand.__init__(self)
        log.debug("init MoveAction")
        self.setText('Move')
        self.g_blocks = scene.selected_blocks()
        self.scene = scene
        self.x = diff.x()
        self.y = diff.y()
        for block in self.g_blocks:
            block.core.states["coordinate"] = (block.x(), block.y())
        self.first = True

    # redo() is called when the MoveAction is first created.
    # At this point, the item is already at the correct position.
    # Therefore, do nothing.
    def redo(self):
        if self.first:
            self.first = False
            return
        for g_block in self.g_blocks:
            g_block.move(self.x, self.y)
        self.scene.update()

    def undo(self):
        for g_block in self.g_blocks:
            g_block.move(-self.x, -self.y)
        self.scene.update()


class EnableAction(ChangeStateAction):
    def __init__(self, scene: FlowgraphScene):
        ChangeStateAction.__init__(self, scene)
        log.debug("init EnableAction")
        self.setText('Enable')
        for i in range(len(self.g_blocks)):
            self.new_states[i]['state'] = 'enabled'


class DisableAction(ChangeStateAction):
    def __init__(self, scene: FlowgraphScene):
        ChangeStateAction.__init__(self, scene)
        log.debug("init DisableAction")
        self.setText('Disable')
        for i in range(len(self.g_blocks)):
            self.new_states[i]['state'] = 'disabled'


class BypassAction(ChangeStateAction):
    def __init__(self, scene: FlowgraphScene):
        ChangeStateAction.__init__(self, scene)
        log.debug("init BypassAction")
        self.setText('Bypass')
        for i in range(len(self.g_blocks)):
            self.new_states[i]['state'] = 'bypassed'


# Change properties
# This can only be performed on one block at a time
class BlockPropsChangeAction(QUndoCommand):
    def __init__(self, scene: FlowgraphScene, c_block: Block):
        QUndoCommand.__init__(self)
        log.debug("init BlockPropsChangeAction")
        self.setText(f'{c_block.name} block: Change properties')
        self.scene = scene
        self.c_block = c_block
        self.old_data = copy(c_block.old_data)
        self.new_data = copy(c_block.export_data())
        self.first = True

    def redo(self):
        if self.first:
            self.first = False
            return
        try:
            name = self.new_data['name']
        except KeyError:
            name = self.new_data['parameters']['id']

        self.c_block.import_data(name, self.new_data['states'], self.new_data['parameters'])
        self.c_block.rewrite()
        self.c_block.validate()
        self.c_block.gui.create_shapes_and_labels()
        self.scene.update()

    def undo(self):
        try:
            name = self.old_data['name']
        except KeyError:
            name = self.old_data['parameters']['id']

        self.c_block.import_data(name, self.old_data['states'], self.old_data['parameters'])
        self.c_block.rewrite()
        self.c_block.validate()
        self.c_block.gui.create_shapes_and_labels()
        self.scene.update()


class BussifyAction(QUndoCommand):
    def __init__(self, scene: FlowgraphScene, direction: str):  # direction is either "sink" or "source"
        QUndoCommand.__init__(self)
        log.debug("init BussifyAction")
        self.setText(f'Toggle bus {direction}')
        self.scene = scene
        self.direction = direction
        self.g_blocks = scene.selected_blocks()

    def bussify(self):
        for g_block in self.g_blocks:
            g_block.core.bussify(self.direction)
        self.scene.update()

    def redo(self):
        self.bussify()

    def undo(self):
        self.bussify()


# Blocks and connections
class NewElementAction(QUndoCommand):
    def __init__(self, scene: FlowgraphScene, element: Element):
        QUndoCommand.__init__(self)
        log.debug("init NewElementAction")
        self.setText('New')
        self.scene = scene
        self.element = element
        self.first = True

    def redo(self):
        if self.first:
            self.first = False
            return

        if self.element.is_block:
            self.scene.core.blocks.append(self.element)
        elif self.element.is_connection:
            self.scene.core.connections.add(self.element)

        self.scene.addItem(self.element.gui)
        self.scene.update()

    def undo(self):
        self.scene.remove_element(self.element.gui)
        self.scene.update()


class DeleteElementAction(QUndoCommand):
    def __init__(self, scene: FlowgraphScene):
        QUndoCommand.__init__(self)
        log.debug("init DeleteElementAction")
        self.setText('Delete')
        self.scene = scene
        self.g_connections = scene.selected_connections()
        self.g_blocks = scene.selected_blocks()
        for block in self.g_blocks:
            for conn in block.core.connections():
                self.g_connections = self.g_connections + [conn.gui]

    def redo(self):
        for con in self.g_connections:
            self.scene.remove_element(con)
        for block in self.g_blocks:
            self.scene.remove_element(block)
        self.scene.update()

    def undo(self):
        for block in self.g_blocks:
            self.scene.core.blocks.append(block.core)
            self.scene.addItem(block)
        for con in self.g_connections:
            self.scene.core.connections.add(con.core)
            self.scene.addItem(con)
        self.scene.update()