# Copyright (c) 2016 Aleph Objects, Inc.
# Cura is released under the terms of the AGPLv3 or higher.

from UM.Mesh.MeshReader import MeshReader
import os
from UM.Scene.SceneNode import SceneNode
from UM.Scene.Iterator.DepthFirstIterator import DepthFirstIterator
from UM.Math.Vector import Vector
from UM.Math.AxisAlignedBox import AxisAlignedBox
from UM.Application import Application
from UM.Message import Message
from UM.Logger import Logger
from UM.Backend.Backend import BackendState

from UM.i18n import i18nCatalog
catalog = i18nCatalog("cura")


from cura import LayerDataBuilder
from cura import LayerDataDecorator
from cura.LayerPolygon import LayerPolygon
from UM.Scene.SliceableObjectDecorator import SliceableObjectDecorator

import numpy
import math
import re


# Class for loading and parsing G-code files
class GCodeReader(MeshReader):
    def __init__(self):
        super(GCodeReader, self).__init__()
        self._supported_extensions = [".gcode", ".g"]
        Application.getInstance().hideMessageSignal.connect(self._onHideMessage)
        self._cancelled = False
        self._message = None
        self._clearValues()
        self._scene_node = None

    def _clearValues(self):
        self._extruder = 0
        self._layer_type = LayerPolygon.Inset0Type
        self._layer = 0
        self._prev_z = 0
        self._layer_data_builder = LayerDataBuilder.LayerDataBuilder()
        self._center_is_zero = False

    @staticmethod
    def _getValue(line, code):
        n = line.find(code)
        if n < 0:
            return None
        n += len(code)
        pattern = re.compile("[;\s]")
        match = pattern.search(line, n)
        m = match.start() if match is not None else -1
        try:
            if m < 0:
                return line[n:]
            return line[n:m]
        except:
            return None

    def _getInt(self, line, code):
        value = self._getValue(line, code)
        try:
            return int(value)
        except:
            return None

    def _getFloat(self, line, code):
        value = self._getValue(line, code)
        try:
            return float(value)
        except:
            return None

    def _onHideMessage(self, message):
        if message == self._message:
            self._cancelled = True

    @staticmethod
    def _getNullBoundingBox():
        return AxisAlignedBox(minimum=Vector(0, 0, 0), maximum=Vector(10, 10, 10))

    def _createPolygon(self, current_z, path):
        countvalid = 0
        for point in path:
            if point[3] > 0:
                countvalid += 1
        if countvalid < 2:
            return False
        try:
            self._layer_data_builder.addLayer(self._layer)
            self._layer_data_builder.setLayerHeight(self._layer, path[0][2])
            self._layer_data_builder.setLayerThickness(self._layer, math.fabs(current_z - self._prev_z))
            this_layer = self._layer_data_builder.getLayer(self._layer)
        except ValueError:
            return False
        count = len(path)
        line_types = numpy.empty((count - 1, 1), numpy.int32)
        line_widths = numpy.empty((count - 1, 1), numpy.float32)
        # TODO: need to calculate actual line width based on E values
        line_widths[:, 0] = 0.5
        points = numpy.empty((count, 3), numpy.float32)
        i = 0
        for point in path:
            points[i, 0] = point[0]
            points[i, 1] = point[2]
            points[i, 2] = -point[1]
            if i > 0:
                line_types[i - 1] = point[3]
            i += 1

        this_poly = LayerPolygon(self._layer_data_builder, self._extruder, line_types, points, line_widths)
        this_poly.buildCache()

        this_layer.polygons.append(this_poly)
        return True

    def _gCode0(self, position, params, path):
        x, y, z, e = position
        xp, yp, zp, ep = params
        x = xp if xp is not None else x
        y = yp if yp is not None else y
        z_changed = False
        if zp is not None:
            if z != zp:
                z_changed = True
                self._prev_z = z
            z = zp
        if ep is not None:
            if ep > e[self._extruder]:
                path.append([x, y, z, self._layer_type])  # extrusion
            else:
                path.append([x, y, z, LayerPolygon.MoveRetractionType])  # retraction
            e[self._extruder] = ep
        else:
            path.append([x, y, z, LayerPolygon.MoveCombingType])
        if z_changed:
            if len(path) > 1 and z > 0:
                if self._createPolygon(z, path):
                    self._layer += 1
                path.clear()
            else:
                path.clear()
        return (x, y, z, e)

    def _gCode28(self, position, params, path):
        x, y, z, e = position
        xp, yp, zp, ep = params
        return (xp if xp is not None else x,
            yp if yp is not None else y,
            0,
            e)

    def _gCode92(self, position, params, path):
        x, y, z, e = position
        xp, yp, zp, ep = params
        if ep is not None:
            e[self._extruder] = ep
        return (xp if xp is not None else x,
            yp if yp is not None else y,
            zp if zp is not None else z,
            e)

    _gCode1 = _gCode0

    def _processGCode(self, G, line, position, path):
        func = getattr(self, "_gCode%s" % G, None)
        x = self._getFloat(line, "X")
        y = self._getFloat(line, "Y")
        z = self._getFloat(line, "Z")
        e = self._getFloat(line, "E")
        if func is not None:
            if (x is not None and x < 0) or (y is not None and y < 0):
                self._center_is_zero = True
            params = (x, y, z, e)
            return func(position, params, path)
        return position

    def _processTCode(self, T, line, position, path):
        self._extruder = T
        if len(path) > 1 and position[2] > 0:
            if self._createPolygon(position[2], path):
                self._layer += 1
            path.clear()
        else:
            path.clear()

    _type_keyword = ";TYPE:"

    def read(self, file_name):
        Logger.log("d", "Preparing to load %s" % file_name)
        self._cancelled = False

        scene_node = SceneNode()
        scene_node.getBoundingBox = self._getNullBoundingBox  # Manually set bounding box, because mesh doesn't have mesh data

        glist = []


        Logger.log("d", "Opening file %s" % file_name)

        with open(file_name, "r") as file:
            file_lines = 0
            current_line = 0
            for line in file:
                file_lines += 1
            file.seek(0)

            file_step = max(math.floor(file_lines / 100), 1)

            self._clearValues()

            self._message = Message(catalog.i18nc("@info:status", "Parsing G-code"), lifetime=0)
            self._message.setProgress(0)
            self._message.show()

            Logger.log("d", "Parsing %s" % file_name)

            current_position = (0, 0, 0, [0, 0])  # x, y, z, e
            current_path = []

            for line in file:
                if self._cancelled:
                    Logger.log("w", "Parsing %s cancelled" % file_name)
                    return None
                current_line += 1
                if current_line % file_step == 0:
                    self._message.setProgress(math.floor(current_line / file_lines * 100))
                if len(line) == 0:
                    continue
                if line.find(self._type_keyword) == 0:
                    type = line[len(self._type_keyword):].strip()
                    if type == "WALL-INNER":
                        self._layer_type = LayerPolygon.InsetXType
                    elif type == "WALL-OUTER":
                        self._layer_type = LayerPolygon.Inset0Type
                    elif type == "SKIN":
                        self._layer_type = LayerPolygon.SkinType
                    elif type == "SKIRT":
                        self._layer_type = LayerPolygon.SkirtType
                    elif type == "SUPPORT":
                        self._layer_type = LayerPolygon.SupportType
                    elif type == "FILL":
                        self._layer_type = LayerPolygon.InfillType
                if line[0] == ";":
                    continue

                G = self._getInt(line, "G")
                if G is not None:
                    current_position = self._processGCode(G, line, current_position, current_path)
                T = self._getInt(line, "T")
                if T is not None:
                    self._processTCode(T, line, current_position, current_path)

            if len(current_path) > 1 and current_position[2] > 0:
                if self._createPolygon(current_position[2], current_path):
                    self._layer += 1
                current_path.clear()

        layer_mesh = self._layer_data_builder.build()
        decorator = LayerDataDecorator.LayerDataDecorator()
        decorator.setLayerData(layer_mesh)
        scene_node.addDecorator(decorator)

        sliceable_decorator = SliceableObjectDecorator()
        sliceable_decorator.setBlockSlicing(True)
        sliceable_decorator.setSliceable(False)
        scene_node.addDecorator(sliceable_decorator)

        Application.getInstance().getController().getScene().gcode_list = glist

        Logger.log("d", "Finished parsing %s" % file_name)
        self._message.hide()

        if self._layer == 0:
            Logger.log("w", "File %s doesn't contain any valid layers" % file_name)

        settings = Application.getInstance().getGlobalContainerStack()
        machine_width = settings.getProperty("machine_width", "value")
        machine_depth = settings.getProperty("machine_depth", "value")

        if not self._center_is_zero:
            scene_node.setPosition(Vector(-machine_width / 2, 0, machine_depth / 2))

        Logger.log("d", "Loaded %s" % file_name)

        return scene_node