# Copyright (c) 2021 Ultimaker B.V.
# Cura is released under the terms of the LGPLv3 or higher.
from .WelcomePagesModel import WelcomePagesModel

import os
from typing import Optional, Dict, List, Tuple
from PyQt5.QtCore import pyqtProperty, pyqtSlot
from UM.Logger import Logger
from UM.Resources import Resources

#
# This Qt ListModel is more or less the same the WelcomePagesModel, except that this model is only for showing the
# "what's new" page. This is also used in the "Help" menu to show the changes log.
#
class WhatsNewPagesModel(WelcomePagesModel):

    image_formats = [".png", ".jpg", ".jpeg", ".gif", ".svg"]
    text_formats = [".txt", ".htm", ".html"]
    image_key = "image"
    text_key = "text"

    @staticmethod
    def _collectOrdinalFiles(resource_type: int, include: List[str]) -> Tuple[Dict[int, str], int]:
        result = {}  #type: Dict[int, str]
        highest = -1
        try:
            folder_path = Resources.getPath(resource_type, "whats_new")
            for _, _, files in os.walk(folder_path):
                for filename in files:
                    basename = os.path.basename(filename)
                    base, ext = os.path.splitext(basename)
                    if ext not in include or not base.isdigit():
                        continue
                    page_no = int(base)
                    highest = max(highest, page_no)
                    result[page_no] = os.path.join(folder_path, filename)
        except FileNotFoundError:
            Logger.logException("w", "Could not find 'whats_new' folder for resource-type {0}".format(resource_type))
        return result, highest

    @staticmethod
    def _loadText(filename: str) -> str:
        result = ""
        try:
            with open(filename, "r", encoding="utf-8") as file:
                result = file.read()
        except OSError:
            Logger.logException("w", "Could not open {0}".format(filename))
        return result

    def initialize(self) -> None:
        self._pages = []
        self._pages.append({"id": "whats_new",
                            "page_url": self._getBuiltinWelcomePagePath("WhatsNewContent.qml"),
                            "next_page_button_text": self._catalog.i18nc("@action:button", "Skip"),
                            "next_page_id": "changelog"
                            })
        self._pages.append({"id": "changelog",
                            "page_url": self._getBuiltinWelcomePagePath("ChangelogContent.qml"),
                            "next_page_button_text": self._catalog.i18nc("@action:button", "Close"),
                            })
        self.setItems(self._pages)

        images, max_image = WhatsNewPagesModel._collectOrdinalFiles(Resources.Images, WhatsNewPagesModel.image_formats)
        texts, max_text = WhatsNewPagesModel._collectOrdinalFiles(Resources.Texts, WhatsNewPagesModel.text_formats)
        highest = max(max_image, max_text)

        self._subpages = []  #type: List[Dict[str, Optional[str]]]
        for n in range(0, highest + 1):
            self._subpages.append({
                WhatsNewPagesModel.image_key: None if n not in images else images[n],
                WhatsNewPagesModel.text_key: None if n not in texts else self._loadText(texts[n])
            })
        if len(self._subpages) == 0:
            self._subpages.append({WhatsNewPagesModel.text_key: "~ There Is Nothing New Under The Sun ~"})

    def _getSubpageItem(self, page: int, item: str) -> Optional[str]:
        if 0 <= page < self.subpageCount and item in self._subpages[page]:
            return self._subpages[page][item]
        else:
            return None

    @pyqtProperty(int, constant = True)
    def subpageCount(self) -> int:
        return len(self._subpages)

    @pyqtSlot(int, result = str)
    def getSubpageImageSource(self, page: int) -> str:
        result = self._getSubpageItem(page, WhatsNewPagesModel.image_key)
        return "file:///" + (result if result else Resources.getPath(Resources.Images, "cura-icon.png"))

    @pyqtSlot(int, result = str)
    def getSubpageText(self, page: int) -> str:
        result = self._getSubpageItem(page, WhatsNewPagesModel.text_key)
        return result if result else "* * *"

__all__ = ["WhatsNewPagesModel"]