# -*- coding: UTF-8 -*-


from gi.repository import Gtk, Gdk, GObject

from pychess.System import conf
from pychess.Utils.Cord import Cord
from pychess.Utils.Move import Move, parseAny, toAN
from pychess.Utils.const import ARTIFICIAL, FLAG_CALL, ABORT_OFFER, LOCAL, TAKEBACK_OFFER, \
    ADJOURN_OFFER, DRAW_OFFER, RESIGNATION, HURRY_ACTION, PAUSE_OFFER, RESUME_OFFER, RUNNING, \
    DROP, DROP_VARIANTS, PAWN, QUEEN, SITTUYINCHESS, QUEEN_PROMOTION

from pychess.Utils.logic import validate
from pychess.Utils.lutils import lmove, lmovegen
from pychess.Utils.lutils.lmove import ParsingError

from . import preferencesDialog
from .PromotionDialog import PromotionDialog
from .BoardView import BoardView, rect, join


class BoardControl(Gtk.EventBox):
    """ Creates a BoardView for GameModel to control move selection,
        action menu selection and emits signals to let Human player
        make moves and emit offers.
        SetuPositionDialog uses setup_position=True to disable most validation.
        When game_preview=True just do circles and arrows
    """

    __gsignals__ = {
        'shapes_changed': (GObject.SignalFlags.RUN_FIRST, None, ()),
        'piece_moved': (GObject.SignalFlags.RUN_FIRST, None, (object, int)),
        'action': (GObject.SignalFlags.RUN_FIRST, None, (str, object, object))
    }

    def __init__(self, gamemodel, action_menu_items, setup_position=False, game_preview=False):
        GObject.GObject.__init__(self)
        self.setup_position = setup_position
        self.game_preview = game_preview

        self.view = BoardView(gamemodel, setup_position=setup_position)

        self.add(self.view)
        self.variant = gamemodel.variant
        self.promotionDialog = PromotionDialog(self.variant.variant)

        self.RANKS = gamemodel.boards[0].RANKS
        self.FILES = gamemodel.boards[0].FILES

        self.action_menu_items = action_menu_items
        self.connections = {}
        for key, menuitem in self.action_menu_items.items():
            if menuitem is None:
                print(key)
            # print("...connect to", key, menuitem)
            self.connections[menuitem] = menuitem.connect(
                "activate", self.actionActivate, key)
        self.view_cid = self.view.connect("shownChanged", self.shownChanged)

        self.gamemodel = gamemodel
        self.gamemodel_cids = []
        self.gamemodel_cids.append(gamemodel.connect("moves_undoing", self.moves_undone))
        self.gamemodel_cids.append(gamemodel.connect("game_ended", self.game_ended))
        self.gamemodel_cids.append(gamemodel.connect("game_started", self.game_started))

        self.cids = []
        self.cids.append(self.connect("button_press_event", self.button_press))
        self.cids.append(self.connect("button_release_event", self.button_release))
        self.add_events(Gdk.EventMask.LEAVE_NOTIFY_MASK |
                        Gdk.EventMask.POINTER_MOTION_MASK)
        self.cids.append(self.connect("motion_notify_event", self.motion_notify))
        self.cids.append(self.connect("leave_notify_event", self.leave_notify))

        self.selected_last = None
        self.normalState = NormalState(self)
        self.selectedState = SelectedState(self)
        self.activeState = ActiveState(self)
        self.lockedNormalState = LockedNormalState(self)
        self.lockedSelectedState = LockedSelectedState(self)
        self.lockedActiveState = LockedActiveState(self)
        self.currentState = self.normalState

        self.lockedPly = self.view.shown
        self.possibleBoards = {
            self.lockedPly: self._genPossibleBoards(self.lockedPly)
        }

        self.allowPremove = False

        def onGameStart(gamemodel):
            if not self.setup_position:
                for player in gamemodel.players:
                    if player.__type__ == LOCAL:
                        self.allowPremove = True

        self.gamemodel_cids.append(gamemodel.connect("game_started", onGameStart))
        self.keybuffer = ""

        self.pre_arrow_from = None
        self.pre_arrow_to = None

    def _del(self):
        self.view.disconnect(self.view_cid)
        for cid in self.cids:
            self.disconnect(cid)

        for obj, conid in self.connections.items():
            # print("...disconnect from ", obj)
            obj.disconnect(conid)
        self.connections = {}
        self.action_menu_items = {}

        for cid in self.gamemodel_cids:
            self.gamemodel.disconnect(cid)

        self.view._del()

        self.promotionDialog = None

        self.normalState = None
        self.selectedState = None
        self.activeState = None
        self.lockedNormalState = None
        self.lockedSelectedState = None
        self.lockedActiveState = None
        self.currentState = None

    def getPromotion(self):
        color = self.view.model.boards[-1].color
        variant = self.view.model.boards[-1].variant
        promotion = self.promotionDialog.runAndHide(color, variant)
        return promotion

    def play_sound(self, move, board):
        if move.is_capture(board):
            sound = "aPlayerCaptures"
        else:
            sound = "aPlayerMoves"

        if board.board.isChecked():
            sound = "aPlayerChecks"

        preferencesDialog.SoundTab.playAction(sound)

    def play_or_add_move(self, board, move):
        if board.board.next is None:
            # at the end of variation or main line
            if not self.view.shownIsMainLine():
                # add move to existing variation
                self.view.model.add_move2variation(board, move, self.view.shown_variation_idx)
                self.view.showNext()
            else:
                # create new variation
                new_vari = self.view.model.add_variation(board, [move])
                self.view.setShownBoard(new_vari[-1])
        else:
            # inside variation or main line
            if board.board.next.lastMove == move.move:
                # replay mainline move
                if self.view.model.lesson_game:
                    next_board = self.view.model.getBoardAtPly(self.view.shown + 1, self.view.shown_variation_idx)
                    self.play_sound(move, board)
                    incr = 1 if len(self.view.model.variations[self.view.shown_variation_idx]) - 1 == board.ply - self.view.model.lowply + 1 else 2
                    if incr == 2:
                        next_next_board = self.view.model.getBoardAtPly(self.view.shown + 2, self.view.shown_variation_idx)
                        # If there is any opponent move variation let the user choose opp next move
                        if any(child for child in next_next_board.board.children if isinstance(child, list)):
                            self.view.infobar.opp_turn()
                            self.view.showNext()
                        # If there is some comment to read let the user read it before opp move
                        elif any(child for child in next_board.board.children if isinstance(child, str)):
                            self.view.infobar.opp_turn()
                            self.view.showNext()

                        # If there is nothing to wait for we make opp next move
                        else:
                            self.view.showNext()
                            self.view.infobar.your_turn()
                            self.view.showNext()
                    else:
                        if self.view.shownIsMainLine():
                            preferencesDialog.SoundTab.playAction("puzzleSuccess")
                            self.view.infobar.get_next_puzzle()
                            self.view.model.emit("learn_success")
                            self.view.showNext()
                        else:
                            self.view.infobar.back_to_mainline()
                            self.view.showNext()
                else:
                    self.view.showNext()

            elif board.board.next.children:
                if self.view.model.lesson_game:
                    self.play_sound(move, board)
                    self.view.infobar.retry()

                # try to find this move in variations
                for i, vari in enumerate(board.board.next.children):
                    for node in vari:
                        if type(node) != str and node.lastMove == move.move and node.plyCount == board.ply + 1:
                            # replay variation move
                            self.view.setShownBoard(node.pieceBoard)
                            return

                # create new variation
                new_vari = self.view.model.add_variation(board, [move])
                self.view.setShownBoard(new_vari[-1])

            else:
                if self.view.model.lesson_game:
                    self.play_sound(move, board)
                    self.view.infobar.retry()

                # create new variation
                new_vari = self.view.model.add_variation(board, [move])
                self.view.setShownBoard(new_vari[-1])

    def emit_move_signal(self, cord0, cord1, promotion=None):
        # Game end can change cord0 to None while dragging a piece
        if cord0 is None:
            return
        board = self.getBoard()
        color = board.color
        # Ask player for which piece to promote into. If this move does not
        # include a promotion, QUEEN will be sent as a dummy value, but not used
        if promotion is None and board[cord0].sign == PAWN and \
                cord1.cord in board.PROMOTION_ZONE[color] and \
                self.variant.variant != SITTUYINCHESS:
            if len(self.variant.PROMOTIONS) == 1:
                promotion = lmove.PROMOTE_PIECE(self.variant.PROMOTIONS[0])
            else:
                if conf.get("autoPromote"):
                    promotion = lmove.PROMOTE_PIECE(QUEEN_PROMOTION)
                else:
                    promotion = self.getPromotion()
                    if promotion is None:
                        # Put back pawn moved be d'n'd
                        self.view.runAnimation(redraw_misc=False)
                        return
        if promotion is None and board[cord0].sign == PAWN and \
                cord0.cord in board.PROMOTION_ZONE[color] and \
                self.variant.variant == SITTUYINCHESS:
            # no promotion allowed if we have queen
            if board.board.boards[color][QUEEN]:
                promotion = None
            # in place promotion
            elif cord1.cord in board.PROMOTION_ZONE[color]:
                promotion = lmove.PROMOTE_PIECE(QUEEN_PROMOTION)
            # queen move promotion (but not a pawn capture!)
            elif board[cord1] is None and (cord0.cord + cord1.cord) % 2 == 1:
                promotion = lmove.PROMOTE_PIECE(QUEEN_PROMOTION)

        if cord0.x < 0 or cord0.x > self.FILES - 1:
            move = Move(lmovegen.newMove(board[cord0].piece, cord1.cord, DROP))
        else:
            move = Move(cord0, cord1, board, promotion)

        if (self.view.model.curplayer.__type__ == LOCAL or self.view.model.examined) and \
                self.view.shownIsMainLine() and \
                self.view.model.boards[-1] == board and \
                self.view.model.status == RUNNING:
            # emit move
            if self.setup_position:
                self.emit("piece_moved", (cord0, cord1), board[cord0].color)
            else:
                self.emit("piece_moved", move, color)
                if self.view.model.examined:
                    self.view.model.connection.bm.sendMove(toAN(board, move))
        else:
            self.play_or_add_move(board, move)

    def actionActivate(self, widget, key):
        """ Put actions from a menu or similar """
        curplayer = self.view.model.curplayer
        if key == "call_flag":
            self.emit("action", FLAG_CALL, curplayer, None)
        elif key == "abort":
            self.emit("action", ABORT_OFFER, curplayer, None)
        elif key == "adjourn":
            self.emit("action", ADJOURN_OFFER, curplayer, None)
        elif key == "draw":
            self.emit("action", DRAW_OFFER, curplayer, None)
        elif key == "resign":
            self.emit("action", RESIGNATION, curplayer, None)
        elif key == "ask_to_move":
            self.emit("action", HURRY_ACTION, curplayer, None)
        elif key == "undo1":
            board = self.view.model.getBoardAtPly(self.view.shown, variation=self.view.shown_variation_idx)
            if board.board.next is not None or board.board.children:
                return
            if not self.view.shownIsMainLine():
                self.view.model.undo_in_variation(board)
                return

            waitingplayer = self.view.model.waitingplayer
            if curplayer.__type__ == LOCAL and \
                    (waitingplayer.__type__ == ARTIFICIAL or
                     self.view.model.isPlayingICSGame()) and \
                    self.view.model.ply - self.view.model.lowply > 1:
                self.emit("action", TAKEBACK_OFFER, curplayer, 2)
            else:
                self.emit("action", TAKEBACK_OFFER, curplayer, 1)
        elif key == "pause1":
            self.emit("action", PAUSE_OFFER, curplayer, None)
        elif key == "resume1":
            self.emit("action", RESUME_OFFER, curplayer, None)

    def shownChanged(self, view, shown):
        if self.view is None:
            return
        self.lockedPly = self.view.shown
        self.possibleBoards[self.lockedPly] = self._genPossibleBoards(
            self.lockedPly)
        if self.view.shown - 2 in self.possibleBoards:
            del self.possibleBoards[self.view.shown - 2]

    def moves_undone(self, gamemodel, moves):
        self.view.selected = None
        self.view.active = None
        self.view.hover = None
        self.view.dragged_piece = None
        self.view.setPremove(None, None, None, None)
        if not self.view.model.examined:
            self.currentState = self.lockedNormalState

    def game_ended(self, gamemodel, reason):
        self.selected_last = None
        self.view.selected = None
        self.view.active = None
        self.view.hover = None
        self.view.dragged_piece = None
        self.view.setPremove(None, None, None, None)
        self.currentState = self.normalState

        self.view.startAnimation()

    def game_started(self, gamemodel):
        if self.view.model.lesson_game:
            if "FEN" in gamemodel.tags:
                if gamemodel.orientation != gamemodel.starting_color:
                    self.view.showNext()
            else:
                self.view.infobar.get_next_puzzle()
                self.view.model.emit("learn_success")

    def getBoard(self):
        return self.view.model.getBoardAtPly(self.view.shown,
                                             self.view.shown_variation_idx)

    def isLastPlayed(self, board):
        return board == self.view.model.boards[-1]

    def setLocked(self, locked):
        do_animation = False

        if locked and self.isLastPlayed(self.getBoard()) and \
                self.view.model.status == RUNNING:
            if self.view.model.status != RUNNING:
                self.view.selected = None
                self.view.active = None
                self.view.hover = None
                self.view.dragged_piece = None
                do_animation = True

            if self.currentState == self.selectedState:
                self.currentState = self.lockedSelectedState
            elif self.currentState == self.activeState:
                self.currentState = self.lockedActiveState
            else:
                self.currentState = self.lockedNormalState
        else:
            if self.currentState == self.lockedSelectedState:
                self.currentState = self.selectedState
            elif self.currentState == self.lockedActiveState:
                self.currentState = self.activeState
            else:
                self.currentState = self.normalState

        if do_animation:
            self.view.startAnimation()

    def setStateSelected(self):
        if self.currentState in (self.lockedNormalState,
                                 self.lockedSelectedState,
                                 self.lockedActiveState):
            self.currentState = self.lockedSelectedState
        else:
            self.view.setPremove(None, None, None, None)
            self.currentState = self.selectedState

    def setStateActive(self):
        if self.currentState in (self.lockedNormalState,
                                 self.lockedSelectedState,
                                 self.lockedActiveState):
            self.currentState = self.lockedActiveState
        else:
            self.view.setPremove(None, None, None, None)
            self.currentState = self.activeState

    def setStateNormal(self):
        if self.currentState in (self.lockedNormalState,
                                 self.lockedSelectedState,
                                 self.lockedActiveState):
            self.currentState = self.lockedNormalState
        else:
            self.view.setPremove(None, None, None, None)
            self.currentState = self.normalState

    def color(self, event):
        state = event.get_state()
        if state & Gdk.ModifierType.SHIFT_MASK and state & Gdk.ModifierType.CONTROL_MASK:
            return "Y"
        elif state & Gdk.ModifierType.SHIFT_MASK:
            return "R"
        elif state & Gdk.ModifierType.CONTROL_MASK:
            return "B"
        else:
            return "G"

    def button_press(self, widget, event):
        if event.button == 3:
            # first we will draw a circle
            cord = self.currentState.point2Cord(event.x, event.y, self.color(event))
            if cord is None or cord.x < 0 or cord.x > self.FILES or cord.y < 0 or cord.y > self.RANKS:
                return
            self.pre_arrow_from = cord
            self.view.pre_circle = cord
            self.view.redrawCanvas()
            return
        else:
            # remove all circles and arrows
            need_redraw = False
            if self.view.arrows:
                self.view.arrows.clear()
                need_redraw = True
            if self.view.circles:
                self.view.circles.clear()
                need_redraw = True
            if self.view.pre_arrow is not None:
                self.view.pre_arrow = None
                need_redraw = True
            if self.view.pre_circle is not None:
                self.view.pre_circle = None
                need_redraw = True
            if need_redraw:
                self.view.redrawCanvas()

        if self.game_preview:
            return
        return self.currentState.press(event.x, event.y, event.button)

    def button_release(self, widget, event):
        if event.button == 3:
            # remove or finalize circle/arrow as needed
            cord = self.currentState.point2Cord(event.x, event.y, self.color(event))
            if cord is None or cord.x < 0 or cord.x > self.FILES or cord.y < 0 or cord.y > self.RANKS:
                return
            if self.view.pre_circle == cord:
                if cord in self.view.circles:
                    self.view.circles.remove(cord)
                else:
                    self.view.circles.add(cord)
                self.view.pre_circle = None
                self.emit("shapes_changed")

            if self.view.pre_arrow is not None:
                if self.view.pre_arrow in self.view.arrows:
                    self.view.arrows.remove(self.view.pre_arrow)
                else:
                    self.view.arrows.add(self.view.pre_arrow)
                self.view.pre_arrow = None
                self.emit("shapes_changed")

            self.pre_arrow_from = None
            self.pre_arrow_to = None
            self.view.redrawCanvas()
            return

        if self.game_preview:
            return
        return self.currentState.release(event.x, event.y)

    def motion_notify(self, widget, event):
        to = self.currentState.point2Cord(event.x, event.y)
        if to is None or to.x < 0 or to.x > self.FILES or to.y < 0 or to.y > self.RANKS:
            return
        if self.pre_arrow_from is not None:
            if to != self.pre_arrow_from:
                # this will be an arrow
                if self.pre_arrow_to is not None and to != self.pre_arrow_to:
                    # first remove the old one
                    self.view.pre_arrow = None
                    self.view.redrawCanvas()

                arrow = self.pre_arrow_from, to
                if arrow != self.view.pre_arrow:
                    # draw the new arrow
                    self.view.pre_arrow = arrow
                    self.view.pre_circle = None
                    self.view.redrawCanvas()
                    self.pre_arrow_to = to

            elif self.view.pre_circle is None:
                # back to circle
                self.view.pre_arrow = None
                self.view.pre_circle = to
                self.view.redrawCanvas()

        return self.currentState.motion(event.x, event.y)

    def leave_notify(self, widget, event):
        return self.currentState.leave(event.x, event.y)

    def key_pressed(self, keyname):
        if keyname in "PNBRQKMFSOox12345678abcdefgh":
            self.keybuffer += keyname

        elif keyname == "minus":
            self.keybuffer += "-"

        elif keyname == "at":
            self.keybuffer += "@"

        elif keyname == "equal":
            self.keybuffer += "="

        elif keyname == "Return":
            color = self.view.model.boards[-1].color
            board = self.view.model.getBoardAtPly(
                self.view.shown, self.view.shown_variation_idx)
            try:
                move = parseAny(board, self.keybuffer)
            except ParsingError:
                self.keybuffer = ""
                return

            if validate(board, move):
                if (self.view.model.curplayer.__type__ == LOCAL or self.view.model.examined) and \
                        self.view.shownIsMainLine() and \
                        self.view.model.boards[-1] == board and \
                        self.view.model.status == RUNNING:
                    # emit move
                    self.emit("piece_moved", move, color)
                    if self.view.model.examined:
                        self.view.model.connection.bm.sendMove(toAN(board, move))
                else:
                    self.play_or_add_move(board, move)
            self.keybuffer = ""

        elif keyname == "BackSpace":
            self.keybuffer = self.keybuffer[:-1] if self.keybuffer else ""

    def _genPossibleBoards(self, ply):
        possible_boards = []
        if self.setup_position:
            return possible_boards
        if len(self.view.model.players) == 2 and self.view.model.isEngine2EngineGame():
            return possible_boards
        curboard = self.view.model.getBoardAtPly(ply,
                                                 self.view.shown_variation_idx)
        for lmove_item in lmovegen.genAllMoves(curboard.board.clone()):
            move = Move(lmove_item)
            board = curboard.move(move)
            possible_boards.append(board)
        return possible_boards


class BoardState:
    """
    There are 6 total BoardStates:
    NormalState, ActiveState, SelectedState
    LockedNormalState, LockedActiveState, LockedSelectedState

    The board state is Locked while it is the opponents turn.
    The board state is not Locked during your turn.
    (Locked states are not used when BoardControl setup_position is True.)

    Normal/Locked State - No pieces or cords are selected
    Active State - A piece is currently being dragged by the mouse
    Selected State - A cord is currently selected
    """

    def __init__(self, board):
        self.parent = board
        self.view = board.view
        self.lastMotionCord = None

        self.RANKS = self.view.model.boards[0].RANKS
        self.FILES = self.view.model.boards[0].FILES

    def getBoard(self):
        return self.view.model.getBoardAtPly(self.view.shown,
                                             self.view.shown_variation_idx)

    def validate(self, cord0, cord1):
        if cord0 is None or cord1 is None:
            return False
        # prevent accidental NULL_MOVE creation
        if cord0 == cord1 and self.parent.variant.variant != SITTUYINCHESS:
            return False
        if self.getBoard()[cord0] is None:
            return False

        if self.parent.setup_position:
            # prevent moving pieces inside holding
            if (cord0.x < 0 or cord0.x > self.FILES - 1) and \
                    (cord1.x < 0 or cord1.x > self.FILES - 1):
                return False
            else:
                return True

        if cord1.x < 0 or cord1.x > self.FILES - 1:
            return False
        if cord0.x < 0 or cord0.x > self.FILES - 1:
            # drop
            return validate(self.getBoard(), Move(lmovegen.newMove(
                self.getBoard()[cord0].piece, cord1.cord, DROP)))
        else:
            return validate(self.getBoard(), Move(cord0, cord1,
                                                  self.getBoard()))

    def transPoint(self, x_loc, y_loc):
        xc_loc, yc_loc, side = self.view.square[0], self.view.square[1], \
            self.view.square[3]
        x_loc, y_loc = self.view.invmatrix.transform_point(x_loc, y_loc)
        y_loc -= yc_loc
        x_loc -= xc_loc

        y_loc /= float(side)
        x_loc /= float(side)
        return x_loc, self.RANKS - y_loc

    def point2Cord(self, x_loc, y_loc, color=None):
        point = self.transPoint(x_loc, y_loc)
        p0_loc, p1_loc = point[0], point[1]
        if self.parent.variant.variant in DROP_VARIANTS:
            if not-3 <= int(p0_loc) <= self.FILES + 2 or not 0 <= int(
                    p1_loc) <= self.RANKS - 1:
                return None
        else:
            if not 0 <= int(p0_loc) <= self.FILES - 1 or not 0 <= int(
                    p1_loc) <= self.RANKS - 1:
                return None
        return Cord(int(p0_loc) if p0_loc >= 0 else int(p0_loc) - 1, int(p1_loc), color)

    def isSelectable(self, cord):
        # Simple isSelectable method, disabling selecting cords out of bound etc
        if not cord:
            return False
        if self.parent.setup_position:
            return True
        if self.parent.variant.variant in DROP_VARIANTS:
            if (not-3 <= cord.x <= self.FILES + 2) or (
                    not 0 <= cord.y <= self.RANKS - 1):
                return False
        else:
            if (not 0 <= cord.x <= self.FILES - 1) or (
                    not 0 <= cord.y <= self.RANKS - 1):
                return False
        return True

    def press(self, x_loc, y_loc, button):
        pass

    def release(self, x_loc, y_loc):
        pass

    def motion(self, x_loc, y_loc):
        cord = self.point2Cord(x_loc, y_loc)
        if self.lastMotionCord == cord:
            return
        self.lastMotionCord = cord
        if cord and self.isSelectable(cord):
            if not self.view.model.isPlayingICSGame():
                self.view.hover = cord
        else:
            self.view.hover = None

    def leave(self, x_loc, y_loc):
        allocation = self.parent.get_allocation()
        if not (0 <= x_loc < allocation.width and 0 <= y_loc < allocation.height):
            self.view.hover = None


class LockedBoardState(BoardState):
    '''
    Parent of LockedNormalState, LockedActiveState, LockedSelectedState

    The board is in one of the three Locked states during the opponent's turn.
    '''

    def __init__(self, board):
        BoardState.__init__(self, board)

    def isAPotentiallyLegalNextMove(self, cord0, cord1):
        """ Determines whether the given move is at all legally possible
            as the next move after the player who's turn it is makes their move
            Note: This doesn't always return the correct value, such as when
            BoardControl.setLocked() has been called and we've begun a drag,
            but view.shown and BoardControl.lockedPly haven't been updated yet """
        if cord0 is None or cord1 is None:
            return False
        if self.parent.lockedPly not in self.parent.possibleBoards:
            return False
        for board in self.parent.possibleBoards[self.parent.lockedPly]:
            if not board[cord0]:
                return False
            if validate(board, Move(cord0, cord1, board)):
                return True
        return False


class NormalState(BoardState):
    '''
    It is the human player's turn and no pieces or cords are selected.
    '''

    def isSelectable(self, cord):
        if not BoardState.isSelectable(self, cord):
            return False
        if self.parent.setup_position:
            return True
        try:
            board = self.getBoard()
            if board[cord] is None:
                return False  # We don't want empty cords
            elif board[cord].color != board.color:
                return False  # We shouldn't be able to select an opponent piece
        except IndexError:
            return False
        return True

    def press(self, x_loc, y_loc, button):
        self.parent.grab_focus()
        cord = self.point2Cord(x_loc, y_loc)
        if self.isSelectable(cord):
            self.view.dragged_piece = self.getBoard()[cord]
            self.view.active = cord
            self.parent.setStateActive()


class ActiveState(BoardState):
    '''
    It is the human player's turn and a piece is being dragged by the mouse.
    '''

    def isSelectable(self, cord):
        if not BoardState.isSelectable(self, cord):
            return False
        if self.parent.setup_position:
            return True
        return self.validate(self.view.active, cord)

    def release(self, x_loc, y_loc):
        cord = self.point2Cord(x_loc, y_loc)
        if self.view.selected and cord != self.view.active and not \
                self.validate(self.view.selected, cord):
            if not self.parent.setup_position:
                preferencesDialog.SoundTab.playAction("invalidMove")
        if not cord:
            self.view.active = None
            self.view.selected = None
            self.view.dragged_piece = None
            self.view.startAnimation()
            self.parent.setStateNormal()

        # When in the mixed active/selected state
        elif self.view.selected:
            # Move when releasing on a good cord
            if self.validate(self.view.selected, cord):
                self.parent.setStateNormal()
                # It is important to emit_move_signal after setting state
                # as listeners of the function probably will lock the board
                self.view.dragged_piece = None
                self.parent.emit_move_signal(self.view.selected, cord)
                if self.parent.setup_position:
                    if not (self.view.selected.x < 0 or
                            self.view.selected.x > self.FILES - 1):
                        self.view.selected = None
                    else:
                        # enable stamping with selected holding pieces
                        self.parent.setStateSelected()
                else:
                    self.view.selected = None
                self.view.active = None
            elif cord == self.view.active == self.view.selected == self.parent.selected_last:
                # user clicked (press+release) same piece twice, so unselect it
                self.view.active = None
                self.view.selected = None
                self.view.dragged_piece = None
                self.view.startAnimation()
                self.parent.setStateNormal()
                if self.parent.variant.variant == SITTUYINCHESS:
                    self.parent.emit_move_signal(self.view.selected, cord)
            else:  # leave last selected piece selected
                self.view.active = None
                self.view.dragged_piece = None
                self.view.startAnimation()
                self.parent.setStateSelected()

        # If dragged and released on a possible cord
        elif self.validate(self.view.active, cord):
            self.parent.setStateNormal()
            self.view.dragged_piece = None
            # removig piece from board
            if self.parent.setup_position and (cord.x < 0 or cord.x > self.FILES - 1):
                self.view.startAnimation()
            self.parent.emit_move_signal(self.view.active, cord)
            self.view.active = None

        # Select last piece user tried to move or that was selected
        elif self.view.active or self.view.selected:
            self.view.selected = self.view.active if self.view.active else self.view.selected
            self.view.active = None
            self.view.dragged_piece = None
            self.view.startAnimation()
            self.parent.setStateSelected()

        # Send back, if dragging to a not possible cord
        else:
            self.view.active = None
            # Send the piece back to its original cord
            self.view.dragged_piece = None
            self.view.startAnimation()
            self.parent.setStateNormal()

        self.parent.selected_last = self.view.selected

    def motion(self, x_loc, y_loc):
        BoardState.motion(self, x_loc, y_loc)
        fcord = self.view.active
        if not fcord:
            return
        piece = self.getBoard()[fcord]
        if not piece:
            return
        elif piece.color != self.getBoard().color:
            if not self.parent.setup_position:
                return

        side = self.view.square[3]
        co_loc, si_loc = self.view.matrix[0], self.view.matrix[1]
        point = self.transPoint(x_loc - side * (co_loc + si_loc) / 2.,
                                y_loc + side * (co_loc - si_loc) / 2.)
        if not point:
            return
        x_loc, y_loc = point

        if piece.x != x_loc or piece.y != y_loc:
            if piece.x:
                paintbox = self.view.cord2RectRelative(piece.x, piece.y)
            else:
                paintbox = self.view.cord2RectRelative(self.view.active)
            paintbox = join(paintbox, self.view.cord2RectRelative(x_loc, y_loc))
            piece.x = x_loc
            piece.y = y_loc
            self.view.redrawCanvas(rect(paintbox))


class SelectedState(BoardState):
    '''
    It is the human player's turn and a cord is selected.
    '''

    def isSelectable(self, cord):
        if not BoardState.isSelectable(self, cord):
            return False
        if self.parent.setup_position:
            return True
        try:
            board = self.getBoard()
            if board[cord] is not None and board[cord].color == board.color:
                return True  # Select another piece
        except IndexError:
            return False
        return self.validate(self.view.selected, cord)

    def press(self, x_loc, y_loc, button):
        cord = self.point2Cord(x_loc, y_loc)
        # Unselecting by pressing the selected cord, or marking the cord to be
        # moved to. We don't unset self.view.selected, so ActiveState can handle
        # things correctly
        if self.isSelectable(cord):
            if self.parent.setup_position:
                color_ok = True
            else:
                color_ok = self.getBoard()[cord] is not None and \
                    self.getBoard()[cord].color == self.getBoard().color
            if self.view.selected and self.view.selected != cord and \
               color_ok and not self.validate(self.view.selected, cord):
                # corner case encountered:
                # user clicked (press+release) a piece, then clicked (no release yet)
                # a different piece and dragged it somewhere else. Since
                # ActiveState.release() will use self.view.selected as the source piece
                # rather than self.view.active, we need to update it here
                self.view.selected = cord  # re-select new cord

            self.view.dragged_piece = self.getBoard()[cord]
            self.view.active = cord
            self.parent.setStateActive()

        else:  # Unselecting by pressing an inactive cord
            self.view.selected = None
            self.parent.setStateNormal()
            if not self.parent.setup_position:
                preferencesDialog.SoundTab.playAction("invalidMove")


class LockedNormalState(LockedBoardState):
    '''
    It is the opponent's turn and no piece or cord is selected.
    '''

    def isSelectable(self, cord):
        if not BoardState.isSelectable(self, cord):
            return False
        if not self.parent.allowPremove:
            return False  # Don't allow premove if neither player is human
        try:
            board = self.getBoard()
            if board[cord] is None:
                return False  # We don't want empty cords
            elif board[cord].color == board.color:
                return False  # We shouldn't be able to select an opponent piece
        except IndexError:
            return False
        return True

    def press(self, x, y, button):
        self.parent.grab_focus()
        cord = self.point2Cord(x, y)
        if self.isSelectable(cord):
            self.view.dragged_piece = self.getBoard()[cord]
            self.view.active = cord
            self.parent.setStateActive()

        # reset premove if mouse right-clicks or clicks one of the premove cords
        if button == 3:  # right-click
            self.view.setPremove(None, None, None, None)
            self.view.startAnimation()
        elif cord == self.view.premove0 or cord == self.view.premove1:
            self.view.setPremove(None, None, None, None)
            self.view.startAnimation()


class LockedActiveState(LockedBoardState):
    '''
    It is the opponent's turn and a piece is being dragged by the mouse.
    '''

    def isSelectable(self, cord):
        if not BoardState.isSelectable(self, cord):
            return False
        return self.isAPotentiallyLegalNextMove(self.view.active, cord)

    def release(self, x_loc, y_loc):
        cord = self.point2Cord(x_loc, y_loc)
        if cord == self.view.active == self.view.selected == self.parent.selected_last:
            # User clicked (press+release) same piece twice, so unselect it
            self.view.active = None
            self.view.selected = None
            self.view.dragged_piece = None
            self.view.startAnimation()
            self.parent.setStateNormal()
        elif self.parent.allowPremove and self.view.selected and self.isAPotentiallyLegalNextMove(
                self.view.selected, cord):
            # In mixed locked selected/active state and user selects a valid premove cord
            board = self.getBoard()
            if board[self.view.selected].sign == PAWN and \
                    cord.cord in board.PROMOTION_ZONE[1 - board.color]:
                if conf.get("autoPromote"):
                    promotion = lmove.PROMOTE_PIECE(QUEEN_PROMOTION)
                else:
                    promotion = self.parent.getPromotion()
            else:
                promotion = None
            self.view.setPremove(board[self.view.selected], self.view.selected,
                                 cord, self.view.shown + 2, promotion)
            self.view.selected = None
            self.view.active = None
            self.view.dragged_piece = None
            self.view.startAnimation()
            self.parent.setStateNormal()
        elif self.parent.allowPremove and self.isAPotentiallyLegalNextMove(
                self.view.active, cord):
            # User drags a piece to a valid premove square
            board = self.getBoard()
            if board[self.view.active].sign == PAWN and \
                    cord.cord in board.PROMOTION_ZONE[1 - board.color]:
                if conf.get("autoPromote"):
                    promotion = lmove.PROMOTE_PIECE(QUEEN_PROMOTION)
                else:
                    promotion = self.parent.getPromotion()
            else:
                promotion = None
            self.view.setPremove(self.getBoard()[self.view.active],
                                 self.view.active, cord, self.view.shown + 2,
                                 promotion)
            self.view.selected = None
            self.view.active = None
            self.view.dragged_piece = None
            self.view.startAnimation()
            self.parent.setStateNormal()
        elif self.view.active or self.view.selected:
            # Select last piece user tried to move or that was selected
            self.view.selected = self.view.active if self.view.active else self.view.selected
            self.view.active = None
            self.view.dragged_piece = None
            self.view.startAnimation()
            self.parent.setStateSelected()
        else:
            self.view.active = None
            self.view.selected = None
            self.view.dragged_piece = None
            self.view.startAnimation()
            self.parent.setStateNormal()

        self.parent.selected_last = self.view.selected

    def motion(self, x_loc, y_loc):
        BoardState.motion(self, x_loc, y_loc)
        fcord = self.view.active
        if not fcord:
            return
        piece = self.getBoard()[fcord]
        if not piece or piece.color == self.getBoard().color:
            return

        side = self.view.square[3]
        co_loc, si_loc = self.view.matrix[0], self.view.matrix[1]
        point = self.transPoint(x_loc - side * (co_loc + si_loc) / 2.,
                                y_loc + side * (co_loc - si_loc) / 2.)
        if not point:
            return
        x_loc, y_loc = point

        if piece.x != x_loc or piece.y != y_loc:
            if piece.x:
                paintbox = self.view.cord2RectRelative(piece.x, piece.y)
            else:
                paintbox = self.view.cord2RectRelative(self.view.active)
            paintbox = join(paintbox, self.view.cord2RectRelative(x_loc, y_loc))
            piece.x = x_loc
            piece.y = y_loc
            self.view.redrawCanvas(rect(paintbox))


class LockedSelectedState(LockedBoardState):
    '''
    It is the opponent's turn and a cord is selected.
    '''

    def isSelectable(self, cord):
        if not BoardState.isSelectable(self, cord):
            return False
        try:
            board = self.getBoard()
            if board[cord] is not None and board[cord].color != board.color:
                return True  # Select another piece
        except IndexError:
            return False
        return self.isAPotentiallyLegalNextMove(self.view.selected, cord)

    def motion(self, x_loc, y_loc):
        cord = self.point2Cord(x_loc, y_loc)
        if self.lastMotionCord == cord:
            self.view.hover = cord
            return
        self.lastMotionCord = cord
        if cord and self.isAPotentiallyLegalNextMove(self.view.selected, cord):
            if not self.view.model.isPlayingICSGame():
                self.view.hover = cord
        else:
            self.view.hover = None

    def press(self, x_loc, y_loc, button):
        cord = self.point2Cord(x_loc, y_loc)
        # Unselecting by pressing the selected cord, or marking the cord to be
        # moved to. We don't unset self.view.selected, so ActiveState can handle
        # things correctly
        if self.isSelectable(cord):
            if self.view.selected and self.view.selected != cord and \
               self.getBoard()[cord] is not None and \
               self.getBoard()[cord].color != self.getBoard().color and \
               not self.isAPotentiallyLegalNextMove(self.view.selected, cord):
                # corner-case encountered (see comment in SelectedState.press)
                self.view.selected = cord  # re-select new cord

            self.view.dragged_piece = self.getBoard()[cord]
            self.view.active = cord
            self.parent.setStateActive()

        else:  # Unselecting by pressing an inactive cord
            self.view.selected = None
            self.parent.setStateNormal()

        # reset premove if mouse right-clicks or clicks one of the premove cords
        if button == 3:  # right-click
            self.view.setPremove(None, None, None, None)
            self.view.startAnimation()
        elif cord == self.view.premove0 or cord == self.view.premove1:
            self.view.setPremove(None, None, None, None)
            self.view.startAnimation()
