from functools import cmp_to_key
from typing import Sequence

from PyQt6.QtCore import (
    QByteArray,
    QCoreApplication,
    QDateTime,
    QFile,
    QFileInfo,
    QStringConverter,
    QStringEncoder,
    qCritical,
    qWarning,
)

import mobase


class OblivionRemasteredGamePlugins(mobase.GamePlugins):
    """
    Reimplementation of GameGamebryo "GamePlugins" code, in the Skyrim style.

    Should properly account for disabled plugins and the loadorder.txt profile file.
    """

    def __init__(self, organizer: mobase.IOrganizer):
        super().__init__()
        self._last_read = QDateTime().currentDateTime()
        self._organizer = organizer
        # Not currently used. These plugins exist in the base game but are not enabled by default.
        self._plugin_blacklist = ["TamrielLevelledRegion.esp", "AltarGymNavigation.esp"]

    def writePluginLists(self, plugin_list: mobase.IPluginList) -> None:
        if not self._last_read.isValid():
            return
        self.writePluginList(
            plugin_list, self._organizer.profile().absolutePath() + "/plugins.txt"
        )
        self.writeLoadOrderList(
            plugin_list, self._organizer.profile().absolutePath() + "/loadorder.txt"
        )
        self._last_read = QDateTime.currentDateTime()

    def readPluginLists(self, plugin_list: mobase.IPluginList) -> None:
        load_order_path = self._organizer.profile().absolutePath() + "/loadorder.txt"
        load_order = self.readLoadOrderList(plugin_list, load_order_path)
        plugin_list.setLoadOrder(load_order)
        self.readPluginList(plugin_list)
        self._last_read = QDateTime.currentDateTime()

    def getLoadOrder(self) -> Sequence[str]:
        load_order_path = self._organizer.profile().absolutePath() + "/loadorder.txt"
        plugins_path = self._organizer.profile().absolutePath() + "/plugins.txt"

        load_order_is_new = (
            not self._last_read.isValid()
            or not QFileInfo(load_order_path).exists()
            or QFileInfo(load_order_path).lastModified() > self._last_read
        )
        plugins_is_new = (
            not self._last_read.isValid()
            or QFileInfo(plugins_path).lastModified() > self._last_read
        )

        if load_order_is_new or not plugins_is_new:
            return self.readLoadOrderList(self._organizer.pluginList(), load_order_path)
        else:
            return self.readPluginList(self._organizer.pluginList())

    def writePluginList(self, plugin_list: mobase.IPluginList, filePath: str):
        self.writeList(plugin_list, filePath, False)

    def writeLoadOrderList(self, plugin_list: mobase.IPluginList, filePath: str):
        self.writeList(plugin_list, filePath, True)

    def writeList(
        self, plugin_list: mobase.IPluginList, filePath: str, load_order: bool
    ):
        plugins_file = open(filePath, "w")
        encoder = (
            QStringEncoder(QStringConverter.Encoding.Utf8)
            if load_order
            else QStringEncoder(QStringConverter.Encoding.System)
        )
        plugins_text = "# This file was automatically generated by Mod Organizer.\n"
        invalid_filenames = False
        written_count = 0
        plugins = plugin_list.pluginNames()
        plugins_sorted = sorted(
            plugins,
            key=cmp_to_key(
                lambda lhs, rhs: plugin_list.priority(lhs) - plugin_list.priority(rhs)
            ),
        )
        for plugin_name in plugins_sorted:
            if (
                load_order
                or plugin_list.state(plugin_name) == mobase.PluginState.ACTIVE
            ):
                result = encoder.encode(plugin_name)
                if encoder.hasError():
                    invalid_filenames = True
                    qCritical("invalid plugin name %s" % plugin_name)
                plugins_text += result.data().decode() + "\n"
                written_count += 1

        if invalid_filenames:
            qCritical(
                QCoreApplication.translate(
                    "MainWindow",
                    "Some of your plugins have invalid names! These "
                    + "plugins can not be loaded by the game. Please see "
                    + "mo_interface.log for a list of affected plugins "
                    + "and rename them.",
                )
            )

        if written_count == 0:
            qWarning(
                "plugin list would be empty, this is almost certainly wrong. Not saving."
            )
        else:
            plugins_file.write(plugins_text)
        plugins_file.close()

    def readLoadOrderList(
        self, plugin_list: mobase.IPluginList, file_path: str
    ) -> list[str]:
        plugin_names = [
            plugin for plugin in self._organizer.managedGame().primaryPlugins()
        ]
        plugin_lookup: set[str] = set()
        for name in plugin_names:
            if name.lower() not in plugin_lookup:
                plugin_lookup.add(name.lower())

        try:
            with open(file_path) as file:
                for line in file:
                    if line.startswith("#"):
                        continue
                    plugin_file = line.rstrip("\n")
                    if plugin_file.lower() not in plugin_lookup:
                        plugin_lookup.add(plugin_file.lower())
                        plugin_names.append(plugin_file)
        except FileNotFoundError:
            return self.readPluginList(plugin_list)

        return plugin_names

    def readPluginList(self, plugin_list: mobase.IPluginList) -> list[str]:
        plugins = [plugin for plugin in plugin_list.pluginNames()]
        sorted_plugins: list[str] = []
        primary = [plugin for plugin in self._organizer.managedGame().primaryPlugins()]
        primary_lower = [plugin.lower() for plugin in primary]
        for plugin_name in primary:
            if plugin_list.state(plugin_name) != mobase.PluginState.MISSING:
                plugin_list.setState(plugin_name, mobase.PluginState.ACTIVE)
            sorted_plugins.append(plugin_name)
        plugin_remove = [
            plugin for plugin in plugins if plugin.lower() in primary_lower
        ]
        for plugin in plugin_remove:
            plugins.remove(plugin)

        plugins_txt_exists = True
        file_path = self._organizer.profile().absolutePath() + "/plugins.txt"
        file = QFile(file_path)
        if not file.open(QFile.OpenModeFlag.ReadOnly):
            plugins_txt_exists = False
        if file.size() == 0:
            plugins_txt_exists = False
        if plugins_txt_exists:
            while not file.atEnd():
                line = file.readLine()
                file_plugin_name = QByteArray()
                if line.size() > 0 and line.at(0).decode() != "#":
                    encoder = QStringEncoder(QStringEncoder.Encoding.System)
                    file_plugin_name = encoder.encode(line.trimmed().data().decode())
                if file_plugin_name.size() > 0:
                    if file_plugin_name.data().decode().lower() in [
                        plugin.lower() for plugin in plugins
                    ]:
                        plugin_list.setState(
                            file_plugin_name.data().decode(), mobase.PluginState.ACTIVE
                        )
                        sorted_plugins.append(file_plugin_name.data().decode())
                        plugins.remove(file_plugin_name.data().decode())

            file.close()

            for plugin_name in plugins:
                plugin_list.setState(plugin_name, mobase.PluginState.INACTIVE)
        else:
            for plugin_name in plugins:
                plugin_list.setState(plugin_name, mobase.PluginState.INACTIVE)

        return sorted_plugins + plugins

    def lightPluginsAreSupported(self) -> bool:
        return False

    def mediumPluginsAreSupported(self) -> bool:
        return False

    def blueprintPluginsAreSupported(self) -> bool:
        return False