"""
Reading OpenStreetMap data from XML file.
"""
import json
from datetime import datetime
from pathlib import Path
from typing import Any, Dict, List, Optional, Set, Union

import numpy as np

from roentgen.ui import progress_bar
from roentgen.util import MinMax

__author__ = "Sergey Vartanov"
__email__ = "me@enzet.ru"

OSM_TIME_PATTERN: str = "%Y-%m-%dT%H:%M:%SZ"


class Tagged:
    """
    OpenStreetMap element (node, way or relation) with tags.
    """
    def __init__(self):
        self.tags: Dict[str, str] = {}

    def get_tag(self, key: str) -> Optional[str]:
        """
        Get tag value or None if it doesn't exist.

        :param key: tag key
        :return: tag value or None
        """
        if key in self.tags:
            return self.tags[key]
        return None


class OSMNode(Tagged):
    """
    OpenStreetMap node.

    See https://wiki.openstreetmap.org/wiki/Node
    """
    def __init__(self):
        super().__init__()

        self.id_: Optional[int] = None
        self.coordinates: Optional[np.array] = None

        self.visible: Optional[str] = None
        self.changeset: Optional[str] = None
        self.timestamp: Optional[datetime] = None
        self.user: Optional[str] = None
        self.uid: Optional[str] = None

    def parse_from_xml(self, text: str, is_full: bool = False) -> "OSMNode":
        """
        Parse from XML node representation.

        :param text: XML node representation
        :param is_full: if false, parse only ID, latitude and longitude
        """
        self.id_ = int(get_value("id", text))
        self.coordinates = np.array((
            float(get_value("lat", text)), float(get_value("lon", text))))

        if is_full:
            self.visible = get_value("visible", text)
            self.changeset = get_value("changeset", text)
            self.timestamp = datetime.strptime(
                get_value("timestamp", text), OSM_TIME_PATTERN
            )
            self.user = get_value("user", text)
            self.uid = get_value("uid", text)

        return self

    def parse_from_structure(self, structure: Dict[str, Any]) -> "OSMNode":
        """
        Parse node from Overpass-like structure.

        :param structure: input structure
        """
        self.id_ = structure["id"]
        self.coordinates = np.array((structure["lat"], structure["lon"]))
        if "tags" in structure:
            self.tags = structure["tags"]

        return self


class OSMWay(Tagged):
    """
    OpenStreetMap way.

    See https://wiki.openstreetmap.org/wiki/Way
    """
    def __init__(self, id_: int = 0, nodes: Optional[List[OSMNode]] = None):
        super().__init__()

        self.id_: int = id_
        self.nodes: List[OSMNode] = [] if nodes is None else nodes

        self.visible: Optional[str] = None
        self.changeset: Optional[str] = None
        self.user: Optional[str] = None
        self.timestamp: Optional[datetime] = None
        self.uid: Optional[str] = None

    def parse_from_xml(self, text: str, is_full: bool = False) -> "OSMWay":
        """
        Parse way from XML way representation.

        :param text: XML way representation
        :param is_full: if false, parse only ID
        """
        self.id_ = int(get_value("id", text))

        if is_full:
            self.visible = get_value("visible", text)
            self.changeset = get_value("changeset", text)
            self.timestamp = datetime.strptime(
                get_value("timestamp", text), OSM_TIME_PATTERN)
            self.user = get_value("user", text)
            self.uid = get_value("uid", text)

        return self

    def parse_from_structure(
        self, structure: Dict[str, Any], nodes
    ) -> "OSMWay":
        """
        Parse way from Overpass-like structure.

        :param structure: input structure
        :param nodes: node structure
        """
        self.id_ = structure["id"]
        for node_id in structure["nodes"]:
            self.nodes.append(nodes[node_id])
        if "tags" in structure:
            self.tags = structure["tags"]

        return self

    def is_cycle(self) -> bool:
        """
        Is way a cycle way or an area boundary.
        """
        return self.nodes[0] == self.nodes[-1]

    def try_to_glue(self, other: "OSMWay") -> Optional["OSMWay"]:
        """
        Create new combined way if ways share endpoints.
        """
        if self.nodes[0] == other.nodes[0]:
            return OSMWay(nodes=list(reversed(other.nodes[1:])) + self.nodes)
        if self.nodes[0] == other.nodes[-1]:
            return OSMWay(nodes=other.nodes[:-1] + self.nodes)
        if self.nodes[-1] == other.nodes[-1]:
            return OSMWay(nodes=self.nodes + list(reversed(other.nodes[:-1])))
        if self.nodes[-1] == other.nodes[0]:
            return OSMWay(nodes=self.nodes + other.nodes[1:])
        return None

    def __repr__(self) -> str:
        return f"Way <{self.id_}> {self.nodes}"


class OSMRelation(Tagged):
    """
    OpenStreetMap relation.

    See https://wiki.openstreetmap.org/wiki/Relation
    """
    def __init__(self, id_: int = 0):
        super().__init__()

        self.id_: int = id_
        self.members: List["OSMMember"] = []
        self.user: Optional[str] = None
        self.timestamp: Optional[datetime] = None

    def parse_from_xml(self, text: str) -> "OSMRelation":
        """
        Parse from XML relation representation.

        :param text: XML way representation
        """
        self.id_ = int(get_value("id", text))

        self.user = get_value("user", text)
        self.timestamp = datetime.strptime(
            get_value("timestamp", text), OSM_TIME_PATTERN)

        return self

    def parse_from_structure(self, structure: Dict[str, Any]) -> "OSMRelation":
        """
        Parse relation from Overpass-like structure.

        :param structure: input structure
        """
        self.id_ = structure["id"]
        for member in structure["members"]:
            mem = OSMMember()
            mem.type_ = member["type"]
            mem.role = member["role"]
            mem.ref = member["ref"]
            self.members.append(mem)
        if "tags" in structure:
            self.tags = structure["tags"]

        return self


class OSMMember:
    """
    Member of OpenStreetMap relation.
    """
    def __init__(self):
        self.type_ = ""
        self.ref = 0
        self.role = ""

    def parse_from_xml(self, text: str) -> "OSMMember":
        """
        Parse relation member from XML way representation.

        :param text: XML relation member representation
        """
        self.type_: str = get_value("type", text)
        self.ref: int = int(get_value("ref", text))
        self.role: str = get_value("role", text)

        return self


def get_value(key: str, text: str):
    """
    Parse xml value from the tag in the format of key="value".
    """
    if key + '="' in text:
        start_index: int = text.find(key + '="') + 2
        end_index: int = start_index + len(key)
        value = text[end_index:text.find('"', end_index)]
        return value

    return None


class Map:
    """
    The whole OpenStreetMap information about nodes, ways, and relations.
    """
    def __init__(self):
        self.node_map: Dict[int, OSMNode] = {}
        self.way_map: Dict[int, OSMWay] = {}
        self.relation_map: Dict[int, OSMRelation] = {}

        self.authors: Set[str] = set()
        self.time: MinMax = MinMax()
        self.boundary_box: List[MinMax] = [MinMax(), MinMax()]

    def add_node(self, node: OSMNode):
        """
        Add node and update map parameters.
        """
        self.node_map[node.id_] = node
        if node.user:
            self.authors.add(node.user)
        self.time.update(node.timestamp)
        self.boundary_box[0].update(node.coordinates[0])
        self.boundary_box[1].update(node.coordinates[1])

    def add_way(self, way: OSMWay):
        """
        Add way and update map parameters.
        """
        self.way_map[way.id_] = way
        if way.user:
            self.authors.add(way.user)
        self.time.update(way.timestamp)

    def add_relation(self, relation: OSMRelation):
        """
        Add relation and update map parameters.
        """
        self.relation_map[relation.id_] = relation


class OverpassReader:
    """
    Reader for JSON structure extracted from Overpass API.

    See https://wiki.openstreetmap.org/wiki/Overpass_API
    """
    def __init__(self):
        self.map_ = Map()

    def parse_json_file(self, file_name: Path) -> Map:
        """
        Parse JSON structure from the file and construct map.
        """
        with file_name.open() as input_file:
            structure = json.load(input_file)

        node_map = {}
        way_map = {}

        for element in structure["elements"]:
            if element["type"] == "node":
                node = OSMNode().parse_from_structure(element)
                node_map[node.id_] = node
                self.map_.add_node(node)
        for element in structure["elements"]:
            if element["type"] == "way":
                way = OSMWay().parse_from_structure(element, node_map)
                way_map[way.id_] = way
                self.map_.add_way(way)
        for element in structure["elements"]:
            if element["type"] == "relation":
                relation = OSMRelation().parse_from_structure(element)
                self.map_.add_relation(relation)

        return self.map_


class OSMReader:
    """
    OSM XML representation reader.
    """
    def __init__(self):
        self.map_ = Map()

    def parse_osm_file(
        self, file_name: Path, parse_nodes: bool = True,
        parse_ways: bool = True, parse_relations: bool = True,
        full: bool = False
    ) -> Map:
        """
        Parse OSM XML representation.

        :param file_name: input OSM XML file name
        """
        with file_name.open() as input_file:
            lines_number: int = sum(1 for _ in input_file)

        print(f"Parsing OSM file {file_name}...")
        line_number: int = 0

        element: Optional[Union[OSMNode, OSMWay, OSMRelation]] = None

        with file_name.open() as input_file:
            for line in input_file.readlines():  # type: str

                line = line.strip()

                line_number += 1
                progress_bar(line_number, lines_number, text="Parsing")

                # Node parsing.

                if line.startswith("<node"):
                    if not parse_nodes:
                        if parse_ways or parse_relations:
                            continue
                        break
                    if line[-2] == "/":
                        node: OSMNode = OSMNode().parse_from_xml(line, full)
                        self.map_.add_node(node)
                    else:
                        element = OSMNode().parse_from_xml(line, full)
                elif line == "</node>":
                    self.map_.add_node(element)

                # Way parsing.

                elif line.startswith("<way"):
                    if not parse_ways:
                        if parse_relations:
                            continue
                        break
                    if line[-2] == "/":
                        way = OSMWay().parse_from_xml(line, full)
                        self.map_.add_way(way)
                    else:
                        element = OSMWay().parse_from_xml(line, full)
                elif line == "</way>":
                    self.map_.add_way(element)

                # Relation parsing.

                elif line.startswith("<relation"):
                    if not parse_relations:
                        break
                    if line[-2] == "/":
                        relation = OSMRelation().parse_from_xml(line)
                        self.map_.add_relation(relation)
                    else:
                        element = OSMRelation().parse_from_xml(line)
                elif line == "</relation>":
                    self.map_.add_relation(element)

                # Elements parsing.

                elif line.startswith("<tag"):
                    key: str = get_value("k", line)
                    value = get_value("v", line)
                    element.tags[key] = value
                elif line.startswith("<nd"):
                    element.nodes.append(
                        self.map_.node_map[int(get_value("ref", line))])
                elif line.startswith("<member"):
                    element.members.append(OSMMember().parse_from_xml(line))

        progress_bar(-1, lines_number, text="Parsing")

        return self.map_