#!/usr/bin/env python3

#    Kosmorro - Compute The Next Ephemerides
#    Copyright (C) 2019  Jérôme Deuchnord <jerome@deuchnord.fr>
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU Affero General Public License as
#    published by the Free Software Foundation, either version 3 of the
#    License, or (at your option) any later version.
#
#    This program 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 Affero General Public License for more details.
#
#    You should have received a copy of the GNU Affero General Public License
#    along with this program.  If not, see <https://www.gnu.org/licenses/>.

from abc import ABC, abstractmethod
import datetime
import json
import os
import tempfile
import subprocess
import shutil
from pathlib import Path

from babel.dates import format_date, format_time
from tabulate import tabulate
from termcolor import colored

from kosmorrolib import AsterEphemerides, Event, EventType
from kosmorrolib.model import ASTERS, MoonPhase

from .i18n.utils import _, FULL_DATE_FORMAT, SHORT_DATETIME_FORMAT, TIME_FORMAT
from .i18n import strings
from .__version__ import __version__ as version
from .exceptions import (
    CompileError,
    UnavailableFeatureError as KosmorroUnavailableFeatureError,
)
from .debug import debug_print


class Dumper(ABC):
    ephemerides: [AsterEphemerides]
    moon_phase: MoonPhase
    events: [Event]
    date: datetime.date
    timezone: int
    with_colors: bool
    show_graph: bool

    def __init__(
        self,
        ephemerides: [AsterEphemerides],
        moon_phase: MoonPhase,
        events: [Event],
        date: datetime.date,
        timezone: int,
        with_colors: bool,
        show_graph: bool,
    ):
        self.ephemerides = ephemerides
        self.moon_phase = moon_phase
        self.events = events
        self.date = date
        self.timezone = timezone
        self.with_colors = with_colors
        self.show_graph = show_graph

    def get_date_as_string(self, capitalized: bool = False) -> str:
        date = format_date(self.date, "full")

        if capitalized:
            return "".join([date[0].upper(), date[1:]])

        return date

    def __str__(self):
        return self.to_string()

    @abstractmethod
    def to_string(self):
        pass

    @staticmethod
    def is_file_output_needed() -> bool:
        return False


class JsonDumper(Dumper):
    SUPPORTED_EVENTS = [
        EventType.OPPOSITION,
        EventType.CONJUNCTION,
        EventType.OCCULTATION,
        EventType.MAXIMAL_ELONGATION,
        EventType.PERIGEE,
        EventType.APOGEE,
    ]

    def to_string(self):
        return json.dumps(
            {
                "ephemerides": [
                    ephemeris.serialize() for ephemeris in self.ephemerides
                ],
                "moon_phase": self.moon_phase.serialize(),
                "events": list(self.get_events()),
            },
            indent=4,
        )

    def get_events(self) -> [{str: any}]:
        for event in self.events:
            if event.event_type not in self.SUPPORTED_EVENTS:
                continue

            yield event.serialize()


class TextDumper(Dumper):
    def to_string(self):
        text = [self.style(self.get_date_as_string(capitalized=True), "h1")]

        if len(self.ephemerides) > 0:
            text.append(self.stringify_ephemerides())

        text.append(self.get_moon(self.moon_phase))

        if len(self.events) > 0:
            events = self.get_events(self.events)
            if events.strip("\n") != "":
                text.append(
                    "\n".join(
                        [
                            self.style(_("Expected events:"), "h2"),
                            events,
                        ]
                    )
                )

        if self.timezone == 0:
            text.append(self.style(_("Note: All the hours are given in UTC."), "em"))
        else:
            tz_offset = str(self.timezone)
            if self.timezone > 0:
                tz_offset = "".join(["+", tz_offset])
            text.append(
                self.style(
                    _(
                        "Note: All the hours are given in the UTC{offset} timezone."
                    ).format(offset=tz_offset),
                    "em",
                )
            )

        return "\n\n".join(text)

    def style(self, text: str, tag: str) -> str:
        if not self.with_colors:
            return text

        styles = {
            "h1": lambda t: colored(t, "green", attrs=["bold"]),
            "h2": lambda t: colored(t, "magenta", attrs=["bold"]),
            "th": lambda t: colored(t, attrs=["bold"]),
            "strong": lambda t: colored(t, attrs=["bold"]),
            "em": lambda t: colored(t, attrs=["dark"]),
        }

        return styles.get(tag, lambda t: t)(text)

    def stringify_ephemerides(self) -> str:
        data = []

        for ephemeris in self.ephemerides:
            object_name = strings.from_object(ephemeris.object.identifier)
            if object_name is None:
                continue

            name = self.style(object_name, "th")

            planet_rise = (
                "-"
                if ephemeris.rise_time is None
                else format_time(ephemeris.rise_time, "short")
            )
            planet_culmination = (
                "-"
                if ephemeris.culmination_time is None
                else format_time(ephemeris.culmination_time, "short")
            )
            planet_set = (
                "-"
                if ephemeris.set_time is None
                else format_time(ephemeris.set_time, "short")
            )

            data.append([name, planet_rise, planet_culmination, planet_set])

        return tabulate(
            data,
            headers=[
                self.style(_("Object"), "th"),
                self.style(_("Rise time"), "th"),
                self.style(_("Culmination time"), "th"),
                self.style(_("Set time"), "th"),
            ],
            tablefmt="simple",
            stralign="center",
            colalign=("left",),
        )

    def get_events(self, events: [Event]) -> str:
        data = []

        for event in events:
            description = strings.from_event(event)
            if description is None:
                continue

            data.append(
                [
                    self.style(format_time(event.start_time, "short"), "th"),
                    description,
                ]
            )

        return tabulate(data, tablefmt="plain", stralign="left")

    def get_moon(self, moon_phase: MoonPhase) -> str:
        if moon_phase is None:
            return _("Moon phase is unavailable for this date.")

        current_moon_phase = " ".join(
            [
                self.style(_("Moon phase:"), "strong"),
                strings.from_moon_phase(moon_phase.phase_type),
            ]
        )
        new_moon_phase = _(
            "{next_moon_phase} on {next_moon_phase_date} at {next_moon_phase_time}"
        ).format(
            next_moon_phase=_(strings.from_moon_phase(moon_phase.get_next_phase())),
            next_moon_phase_date=format_date(moon_phase.next_phase_date, "full"),
            next_moon_phase_time=format_time(moon_phase.next_phase_date, "short"),
        )

        return "\n".join([current_moon_phase, new_moon_phase])


class _LatexDumper(Dumper):
    def to_string(self):
        template_path = os.path.join(
            os.path.abspath(os.path.dirname(__file__)), "assets", "pdf", "template.tex"
        )

        with open(template_path, mode="r") as file:
            template = file.read()

        return self._make_document(template)

    def _make_document(self, template: str) -> str:
        kosmorro_logo_path = os.path.join(
            os.path.abspath(os.path.dirname(__file__)),
            "assets",
            "png",
            "kosmorro-logo.png",
        )

        moon_phase_graphics = os.path.join(
            os.path.abspath(os.path.dirname(__file__)),
            "assets",
            "moonphases",
            "png",
            ".".join(
                [self.moon_phase.phase_type.name.lower().replace("_", "-"), "png"]
            ),
        )

        document = template

        if self.ephemerides is None:
            document = self._remove_section(document, "ephemerides")

        if len(self.events) == 0:
            document = self._remove_section(document, "events")

        document = self.add_strings(document, kosmorro_logo_path, moon_phase_graphics)

        if self.show_graph:
            # The graphephemerides environment beginning tag must end with a percent symbol to ensure
            # that no extra space will interfere with the graph.
            document = document.replace(
                r"\begin{ephemerides}", r"\begin{graphephemerides}%"
            ).replace(r"\end{ephemerides}", r"\end{graphephemerides}")

        return document

    def add_strings(
        self, document: str, kosmorro_logo_path: str, moon_phase_graphics: str
    ) -> str:
        document = document.replace("+++KOSMORRO-VERSION+++", version)
        document = document.replace("+++KOSMORRO-LOGO+++", kosmorro_logo_path)
        document = document.replace("+++DOCUMENT-TITLE+++", _("Overview of your sky"))
        document = document.replace(
            "+++DOCUMENT-DATE+++", self.get_date_as_string(capitalized=True)
        )
        document = document.replace(
            "+++INTRODUCTION+++",
            "\n\n".join(
                [
                    _(
                        "This document summarizes the ephemerides and the events of {date}. "
                        "It aims to help you to prepare your observation session. "
                        "All the hours are given in {timezone}."
                    ).format(
                        date=self.get_date_as_string(),
                        timezone="UTC+%d" % self.timezone
                        if self.timezone != 0
                        else "UTC",
                    ),
                    _(
                        "Don't forget to check the weather forecast before you go out with your equipment."
                    ),
                ]
            ),
        )
        document = document.replace(
            "+++SECTION-EPHEMERIDES+++", _("Ephemerides of the day")
        )
        document = document.replace("+++EPHEMERIDES-OBJECT+++", _("Object"))
        document = document.replace("+++EPHEMERIDES-RISE-TIME+++", _("Rise time"))
        document = document.replace(
            "+++EPHEMERIDES-CULMINATION-TIME+++", _("Culmination time")
        )
        document = document.replace("+++EPHEMERIDES-SET-TIME+++", _("Set time"))
        document = document.replace("+++EPHEMERIDES+++", self._make_ephemerides())
        document = document.replace("+++GRAPH_LABEL_HOURS+++", _("hours"))
        document = document.replace("+++MOON-PHASE-GRAPHICS+++", moon_phase_graphics)
        document = document.replace("+++CURRENT-MOON-PHASE-TITLE+++", _("Moon phase:"))
        document = document.replace(
            "+++CURRENT-MOON-PHASE+++",
            strings.from_moon_phase(self.moon_phase.phase_type),
        )
        document = document.replace("+++SECTION-EVENTS+++", _("Expected events"))
        document = document.replace("+++EVENTS+++", self._make_events())

        for aster in ASTERS:
            object_name = strings.from_object(aster.identifier)
            if object_name is None:
                continue

            document = document.replace(
                "+++ASTER_%s+++" % aster.identifier.name,
                object_name,
            )

        return document

    def _make_ephemerides(self) -> str:
        latex = []
        graph_y_component = 18

        if self.ephemerides is not None:
            for ephemeris in self.ephemerides:
                aster_rise = (
                    "-"
                    if ephemeris.rise_time is None
                    else format_time(ephemeris.rise_time, "short")
                )
                aster_culmination = (
                    "-"
                    if ephemeris.culmination_time is None
                    else format_time(ephemeris.culmination_time, "short")
                )
                aster_set = (
                    "-"
                    if ephemeris.set_time is None
                    else format_time(ephemeris.set_time, "short")
                )

                if not self.show_graph:
                    object_name = strings.from_object(ephemeris.object.identifier)
                    if object_name is not None:
                        latex.append(
                            r"\object{%s}{%s}{%s}{%s}"
                            % (
                                object_name,
                                aster_rise,
                                aster_culmination,
                                aster_set,
                            )
                        )
                else:
                    if ephemeris.rise_time is not None:
                        raise_hour = ephemeris.rise_time.hour
                        raise_minute = ephemeris.rise_time.minute
                    else:
                        raise_hour = raise_minute = 0
                        aster_rise = ""

                    if ephemeris.set_time is not None:
                        set_hour = ephemeris.set_time.hour
                        set_minute = ephemeris.set_time.minute
                    else:
                        set_hour = 24
                        set_minute = 0
                        aster_set = ""
                    sets_after_end = set_hour > raise_hour

                    if not sets_after_end:
                        latex.append(
                            r"\graphobject{%d}{gray}{0}{0}{%d}{%d}{}{%s}"
                            % (graph_y_component, set_hour, set_minute, aster_set)
                        )
                        set_hour = 24
                        set_minute = 0

                    latex.append(
                        r"\graphobject{%d}{gray}{%d}{%d}{%d}{%d}{%s}{%s}"
                        % (
                            graph_y_component,
                            raise_hour,
                            raise_minute,
                            set_hour,
                            set_minute,
                            aster_rise,
                            aster_set if sets_after_end else "",
                        )
                    )
                    graph_y_component -= 2

        return "".join(latex)

    def _make_events(self) -> str:
        latex = []

        for event in self.events:
            event_name = strings.from_event(event)
            if event_name is None:
                continue

            latex.append(
                r"\event{%s}{%s}" % (format_time(event.start_time, "short"), event_name)
            )

        return "".join(latex)

    @staticmethod
    def _remove_section(document: str, section: str):
        begin_section_tag = "%%%%%% BEGIN-%s-SECTION" % section.upper()
        end_section_tag = "%%%%%% END-%s-SECTION" % section.upper()

        document = document.split("\n")
        new_document = []

        ignore_line = False
        for line in document:
            if begin_section_tag in line or end_section_tag in line:
                ignore_line = not ignore_line
                continue
            if ignore_line:
                continue
            new_document.append(line)

        return "\n".join(new_document)


class PdfDumper(Dumper):
    def to_string(self):
        try:
            latex_dumper = _LatexDumper(
                self.ephemerides,
                self.moon_phase,
                self.events,
                date=self.date,
                timezone=self.timezone,
                with_colors=self.with_colors,
                show_graph=self.show_graph,
            )

            return self._compile(latex_dumper.to_string())
        except RuntimeError as error:
            raise KosmorroUnavailableFeatureError(
                _(
                    "Building PDF was not possible, because some dependencies are not"
                    " installed.\nPlease look at the documentation at https://kosmorro.space/cli/generate-pdf/ "
                    "for more information."
                )
            ) from error

    @staticmethod
    def is_file_output_needed() -> bool:
        return True

    @staticmethod
    def _compile(latex_input) -> bytes:
        package = str(Path(__file__).parent.absolute()) + "/assets/pdf/kosmorro.sty"
        timestamp = datetime.datetime.now().strftime("%Y%m%d%H%M%S")
        current_dir = (
            os.getcwd()
        )  # Keep the current directory to return to it after the PDFLaTeX execution

        try:
            temp_dir = tempfile.mkdtemp()

            shutil.copy(package, temp_dir)

            temp_tex = "%s/%s.tex" % (temp_dir, timestamp)

            with open(temp_tex, "w") as tex_file:
                tex_file.write(latex_input)

            os.chdir(temp_dir)
            debug_print("LaTeX content:\n%s" % latex_input)

            subprocess.run(
                ["pdflatex", "-interaction", "nonstopmode", "%s.tex" % timestamp],
                capture_output=True,
                check=True,
            )

            os.chdir(current_dir)

            with open("%s/%s.pdf" % (temp_dir, timestamp), "rb") as pdffile:
                return bytes(pdffile.read())

        except FileNotFoundError as error:
            raise KosmorroUnavailableFeatureError(
                "TeXLive is not installed."
            ) from error

        except subprocess.CalledProcessError as error:
            with open("/tmp/kosmorro-%s.log" % timestamp, "wb") as file:
                file.write(error.stdout)

            raise CompileError(
                _(
                    "An error occurred during the compilation of the PDF.\n"
                    "Please open an issue at https://github.com/Kosmorro/kosmorro/issues and share "
                    "the content of the log file at /tmp/kosmorro-%s.log" % timestamp
                )
            ) from error