# Copyright (C) 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018  Rickard Lindberg, Roger Lindberg
#
# This file is part of Timeline.
#
# Timeline 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.
#
# Timeline 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 Timeline.  If not, see <http://www.gnu.org/licenses/>.


from os.path import abspath
import base64
import re
import shutil
import io

import wx

from timelinelib.calendar.bosparanian.timetype import BosparanianTimeType
from timelinelib.calendar.gregorian.timetype import GregorianTimeType
from timelinelib.calendar.num.timetype import NumTimeType
from timelinelib.calendar.coptic.timetype import CopticTimeType
from timelinelib.calendar.pharaonic.timetype import PharaonicTimeType
from timelinelib.canvas.data.db import MemoryDB
from timelinelib.canvas.data.exceptions import TimelineIOError
from timelinelib.canvas.data import Category
from timelinelib.canvas.data import Container
from timelinelib.canvas.data import Era
from timelinelib.canvas.data import Event
from timelinelib.canvas.data import Subevent
from timelinelib.canvas.data import TimePeriod
from timelinelib.canvas.data.milestone import Milestone
from timelinelib.db.utils import create_non_exising_path
from timelinelib.general.xmlparser import ANY
from timelinelib.general.xmlparser import OPTIONAL
from timelinelib.general.xmlparser import parse
from timelinelib.general.xmlparser import parse_fn_store
from timelinelib.general.xmlparser import parse_fn_store_to_list
from timelinelib.general.xmlparser import SINGLE
from timelinelib.general.xmlparser import Tag
from timelinelib.utils import ex_msg


def import_db_from_timeline_xml(path):
    db = MemoryDB()
    db.path = path
    db.set_time_type(GregorianTimeType())
    Parser(db, path).parse()
    db.clear_transactions()
    return db


class ParseException(Exception):
    """Thrown if parsing of data read from file fails."""
    pass


class Parser(object):

    def __init__(self, db, path):
        self.db = db
        self.path = path
        self._containers_by_cid = {}

    def parse(self):
        self._load()

    def _load(self):
        try:
            # _parse_version will create the rest of the schema dynamically
            partial_schema = Tag("timeline", SINGLE, None, [
                Tag("version", SINGLE, self._parse_version)
            ])
            tmp_dict = {
                "partial_schema": partial_schema,
                "category_map": {},
                "hidden_categories": [],
            }
            parse(self.path, partial_schema, tmp_dict)
        except Exception as e:
            msg = _("Unable to read timeline data from '%s'.")
            whole_msg = (msg + "\n\n%s") % (abspath(self.path), ex_msg(e))
            raise TimelineIOError(whole_msg)

    def _parse_version(self, text, tmp_dict):
        match = re.search(r"^(\d+).(\d+).(\d+)(.*)$", text)
        if match:
            (x, y, z) = (int(match.group(1)), int(match.group(2)),
                         int(match.group(3)))
            self._backup((x, y, z))
            tmp_dict["version"] = (x, y, z)
            self._create_rest_of_schema(tmp_dict)
        else:
            raise ParseException("Could not parse version number from '%s'."
                                 % text)

    def _backup(self, current_version):
        (x, _, _) = current_version
        if x == 0:
            shutil.copy(self.path,
                        create_non_exising_path(self.path, "pre100bak"))

    def _create_rest_of_schema(self, tmp_dict):
        """
        Ensure all versions of the xml format can be parsed with this schema.

        tmp_dict["version"] can be used to create different schemas depending
        on the version.
        """
        tmp_dict["partial_schema"].add_child_tags([
            Tag("timetype", OPTIONAL, self._parse_timetype),
            Tag("eras", OPTIONAL, None, [
                Tag("era", ANY, self._parse_era, [
                    Tag("name", SINGLE, parse_fn_store("tmp_name")),
                    Tag("start", SINGLE, parse_fn_store("tmp_start")),
                    Tag("end", SINGLE, parse_fn_store("tmp_end")),
                    Tag("color", SINGLE, parse_fn_store("tmp_color")),
                    Tag("ends_today", OPTIONAL, parse_fn_store("tmp_ends_today")),
                ])
            ]),
            Tag("categories", SINGLE, None, [
                Tag("category", ANY, self._parse_category, [
                    Tag("name", SINGLE, parse_fn_store("tmp_name")),
                    Tag("color", SINGLE, parse_fn_store("tmp_color")),
                    Tag("progress_color", OPTIONAL, parse_fn_store("tmp_progress_color")),
                    Tag("done_color", OPTIONAL, parse_fn_store("tmp_done_color")),
                    Tag("font_color", OPTIONAL, parse_fn_store("tmp_font_color")),
                    Tag("parent", OPTIONAL, parse_fn_store("tmp_parent")),
                ])
            ]),
            Tag("events", SINGLE, None, [
                Tag("event", ANY, self._parse_event, [
                    Tag("start", SINGLE, parse_fn_store("tmp_start")),
                    Tag("end", SINGLE, parse_fn_store("tmp_end")),
                    Tag("text", SINGLE, parse_fn_store("tmp_text")),
                    Tag("progress", OPTIONAL, parse_fn_store("tmp_progress")),
                    Tag("fuzzy", OPTIONAL, parse_fn_store("tmp_fuzzy")),
                    Tag("locked", OPTIONAL, parse_fn_store("tmp_locked")),
                    Tag("ends_today", OPTIONAL, parse_fn_store("tmp_ends_today")),
                    Tag("category", OPTIONAL, parse_fn_store("tmp_category")),
                    Tag("categories", OPTIONAL, None, [
                        Tag("category", ANY, parse_fn_store_to_list("tmp_categories"))
                    ]),
                    Tag("description", OPTIONAL, parse_fn_store("tmp_description")),
                    Tag("alert", OPTIONAL, parse_fn_store("tmp_alert")),
                    Tag("hyperlink", OPTIONAL, parse_fn_store("tmp_hyperlink")),
                    Tag("icon", OPTIONAL, parse_fn_store("tmp_icon")),
                    Tag("default_color", OPTIONAL, parse_fn_store("tmp_default_color")),
                    Tag("milestone", OPTIONAL, parse_fn_store("tmp_milestone")),
                ])
            ]),
            Tag("view", SINGLE, None, [
                Tag("displayed_period", OPTIONAL,
                    self._parse_displayed_period, [
                        Tag("start", SINGLE, parse_fn_store("tmp_start")),
                        Tag("end", SINGLE, parse_fn_store("tmp_end")),
                    ]),
                Tag("hidden_categories", OPTIONAL,
                    self._parse_hidden_categories, [
                        Tag("name", ANY, self._parse_hidden_category),
                    ]),
            ]),
            Tag("now", OPTIONAL, self._parse_saved_now),
        ])

    def _parse_timetype(self, text, tmp_dict):
        self.db.set_time_type(None)
        valid_time_types = (GregorianTimeType(), BosparanianTimeType(), NumTimeType(), CopticTimeType(), PharaonicTimeType())
        for timetype in valid_time_types:
            if text == timetype.get_name():
                self.db.set_time_type(timetype)
                break
        if self.db.get_time_type() is None:
            raise ParseException("Invalid timetype '%s' found." % text)

    def _parse_category(self, text, tmp_dict):
        name = tmp_dict.pop("tmp_name")
        color = parse_color(tmp_dict.pop("tmp_color"))
        progress_color = self._parse_optional_color(tmp_dict, "tmp_progress_color", None)
        done_color = self._parse_optional_color(tmp_dict, "tmp_done_color", None)
        font_color = self._parse_optional_color(tmp_dict, "tmp_font_color")
        parent_name = tmp_dict.pop("tmp_parent", None)
        if parent_name:
            parent = tmp_dict["category_map"].get(parent_name, None)
            if parent is None:
                raise ParseException("Parent category '%s' not found." % parent_name)
        else:
            parent = None
        category = Category().update(name, color, font_color, parent=parent)
        if progress_color:
            category.set_progress_color(progress_color)
        if done_color:
            category.set_done_color(done_color)
        old_category = self.db.get_category_by_name(name)
        if old_category is not None:
            category = old_category
        if name not in tmp_dict["category_map"]:
            tmp_dict["category_map"][name] = category
            self.db.save_category(category)

    def _parse_event(self, text, tmp_dict):
        start = self._parse_time(tmp_dict.pop("tmp_start"))
        end = self._parse_time(tmp_dict.pop("tmp_end"))
        text = tmp_dict.pop("tmp_text")
        progress = self._parse_optional_int(tmp_dict, "tmp_progress")
        fuzzy = self._parse_optional_bool(tmp_dict, "tmp_fuzzy")
        locked = self._parse_optional_bool(tmp_dict, "tmp_locked")
        ends_today = self._parse_optional_bool(tmp_dict, "tmp_ends_today")
        category_text = tmp_dict.pop("tmp_category", None)
        if category_text is None:
            category = None
        else:
            category = self.get_category(tmp_dict, category_text)
        categories = []
        if "tmp_categories" in tmp_dict:
            # Remove duplicates but preserve order
            dic = {k: 0 for k in tmp_dict.pop("tmp_categories", None)}
            for category_text in dic:
                if category_text is not None:
                    cat = self.get_category(tmp_dict, category_text)
                    if category is None:
                        category = cat
                    else:
                        categories.append(cat)
        description = tmp_dict.pop("tmp_description", None)
        alert_string = tmp_dict.pop("tmp_alert", None)
        alert = parse_alert_string(self.db.get_time_type(), alert_string)
        icon_text = tmp_dict.pop("tmp_icon", None)
        if icon_text is None:
            icon = None
        else:
            icon = parse_icon(icon_text)
        hyperlink = tmp_dict.pop("tmp_hyperlink", None)
        milestone = self._parse_optional_bool(tmp_dict, "tmp_milestone")
        if self._is_container_event(text):
            cid, text = self._extract_container_id(text)
            event = Container().update(start, end, text, category)
            self._containers_by_cid[cid] = event
        elif self._is_subevent(text):
            cid, text = self._extract_subid(text)
            event = Subevent().update(
                start,
                end,
                text,
                category,
                locked=locked,
                ends_today=ends_today
            )
            event.container = self._containers_by_cid[cid]
        elif milestone:
            event = Milestone().update(start, start, text)
            event.set_category(category)
        else:
            if self._text_starts_with_added_space(text):
                text = self._remove_added_space(text)
            event = Event().update(start, end, text, category, fuzzy, locked, ends_today)
        if categories:
            event.set_categories(categories)
        default_color = tmp_dict.pop("tmp_default_color", "200,200,200")
        event.set_data("description", description)
        event.set_data("icon", icon)
        event.set_data("alert", alert)
        event.set_data("hyperlink", hyperlink)
        event.set_data("progress", int(progress))
        event.set_data("default_color", parse_color(default_color))
        self.db.save_event(event)

    def get_category(self, tmp_dict, category_text):
        cat = tmp_dict["category_map"].get(category_text, None)
        if cat is None:
            raise ParseException("Category '%s' not found." % category_text)
        return cat

    def _parse_era(self, text, tmp_dict):
        name = tmp_dict.pop("tmp_name")
        start = self._parse_time(tmp_dict.pop("tmp_start"))
        end = self._parse_time(tmp_dict.pop("tmp_end"))
        color = parse_color(tmp_dict.pop("tmp_color"))
        ends_today = self._parse_optional_bool(tmp_dict, "tmp_ends_today")
        era = Era().update(start, end, name, color)
        era.set_ends_today(ends_today)
        self.db.save_era(era)

    def _text_starts_with_added_space(self, text):
        return text[0:2] in (" (", " [")

    def _remove_added_space(self, text):
        return text[1:]

    def _is_container_event(self, text):
        return text.startswith("[")

    def _is_subevent(self, text):
        return text.startswith("(")

    def _extract_container_id(self, text):
        str_id, text = text.split("]", 1)
        try:
            str_id = str_id[1:]
            cid = int(str_id)
        except:
            cid = -1
        return cid, text

    def _extract_subid(self, text):
        cid, text = text.split(")", 1)
        try:
            cid = int(cid[1:])
        except:
            cid = -1
        return cid, text

    def _parse_optional_bool(self, tmp_dict, cid):
        if cid in tmp_dict:
            return tmp_dict.pop(cid) == "True"
        else:
            return False

    def _parse_optional_int(self, tmp_dict, cid):
        if cid in tmp_dict:
            return int(tmp_dict.pop(cid))
        else:
            return 0

    def _parse_optional_color(self, tmp_dict, cid, missing_value=(0, 0, 0)):
        if cid in tmp_dict:
            return parse_color(tmp_dict.pop(cid))
        else:
            return missing_value

    def _parse_displayed_period(self, text, tmp_dict):
        start = self._parse_time(tmp_dict.pop("tmp_start"))
        end = self._parse_time(tmp_dict.pop("tmp_end"))
        self.db.set_displayed_period(TimePeriod(start, end))

    def _parse_hidden_category(self, text, tmp_dict):
        category = tmp_dict["category_map"].get(text, None)
        if category is None:
            raise ParseException("Category '%s' not found." % text)
        tmp_dict["hidden_categories"].append(category)

    def _parse_hidden_categories(self, text, tmp_dict):
        self.db.set_hidden_categories(tmp_dict.pop("hidden_categories"))

    def _parse_time(self, time_string):
        return self.db.get_time_type().parse_time(time_string)

    def _parse_saved_now(self, text, tmp_dict):
        time = self.db.time_type.parse_time(text)
        self.db.set_saved_now(time)


def parse_color(color_string):
    """
    Expected format 'r,g,b'.

    Return a tuple (r, g, b).
    """
    def verify_255_number(num):
        if num < 0 or num > 255:
            raise ParseException("Color number not in range [0, 255], "
                                 "color string = '%s'" % color_string)
    match = re.search(r"^(\d+),(\d+),(\d+)$", color_string)
    if match:
        r, g, b = int(match.group(1)), int(match.group(2)), int(match.group(3))
        verify_255_number(r)
        verify_255_number(g)
        verify_255_number(b)
        return (r, g, b)
    else:
        raise ParseException("Color not on correct format, color string = '%s'"
                             % color_string)


def parse_icon(string):
    """
    Expected format: base64 encoded png image.

    Return a wx.Bitmap.
    """
    try:
        icon_string = io.StringIO(base64.b64decode(string))
        image = wx.ImageFromStream(icon_string, wx.BITMAP_TYPE_PNG)
        return image.ConvertToBitmap()
    except:
        raise ParseException("Could not parse icon from '%s'." % string)


def parse_alert_string(time_type, alert_string):
    if alert_string is not None:
        try:
            time_string, alert_text = alert_string.split(";", 1)
            alert_time = time_type.parse_time(time_string)
            alert = (alert_time, alert_text)
        except:
            raise ParseException("Could not parse alert from '%s'." % alert_string)
    else:
        alert = None
    return alert
