"""
Filename: welcome.py
Description: Welcome dialog window
Note: Compliant with pylance strict type checking

Author: Tyler de Zeeuw
License: GPL-3.0
"""

# External library imports
from PySide6.QtWidgets import QTextBrowser, QVBoxLayout, QLabel, QDialog, QHBoxLayout, QPushButton
from PySide6.QtGui import QDesktopServices, QIcon
from PySide6.QtCore import QUrl
from PySide6.QtNetwork import QNetworkAccessManager, QNetworkRequest, QNetworkReply

from src.shared.shareddata import APP_NAME, PLATFORM_NAME, CURRENT_VERSION, CHANGELOG_URL, resource_path


class WelcomeDialog(QDialog):
    def __init__(self, parent: QDialog | None = None, direct: bool = True, first: bool = False):
        super().__init__(parent)
        self.setWindowTitle(f"What's New - {APP_NAME.upper()}")
        self.setMinimumSize(550, 450)
        self.resize(800, 500)

        layout = QVBoxLayout(self)

        header_layout = QHBoxLayout()
        logo_label = QLabel(self)

        icon_ext = "icns" if PLATFORM_NAME == "darwin" else "ico"
        logo_label.setPixmap(QIcon(resource_path(f"icons/main.{icon_ext}")).pixmap(48, 48))
        if first:
            title_label = QLabel(f"<h2>Welcome to {APP_NAME.upper()}!</h2>", self)
        elif direct:
            title_label = QLabel(f"<h2>{APP_NAME.upper()} has been sucessfully updated to version {CURRENT_VERSION}!</h2>", self)
        else:
            title_label = QLabel(f"<h2>{APP_NAME.upper()} is currently running version {CURRENT_VERSION}.</h2>", self)

        header_layout.addWidget(logo_label)
        header_layout.addWidget(title_label)
        header_layout.addStretch()
        layout.addLayout(header_layout)

        self.text_browser = QTextBrowser(self)
        self.text_browser.setHtml("<p style='color: gray;'>Loading latest updates from server...</p>")

        # Ensure links open in the default web browser and not in this window
        self.text_browser.setOpenLinks(False)
        self.text_browser.anchorClicked.connect(QDesktopServices.openUrl)
        layout.addWidget(self.text_browser)

        footer_layout = QHBoxLayout()

        ok_button = QPushButton("OK", self)
        ok_button.setDefault(True)
        ok_button.clicked.connect(self.accept)

        footer_layout.addStretch()
        footer_layout.addWidget(ok_button)
        layout.addLayout(footer_layout)

        # Fetch markdown from the web asynchronously
        self.network_manager = QNetworkAccessManager(self)
        self.network_manager.finished.connect(self._on_download_complete)
        self.network_manager.get(QNetworkRequest(QUrl(CHANGELOG_URL)))


    def _on_download_complete(self, reply: QNetworkReply) -> None:
        """Processes the downloaded markdown and drops it into the view frame."""
        if reply.error() == reply.NetworkError.NoError:
            raw_bytes = reply.readAll().data()

            # Convert raw bytes to standard text string
            markdown_text = str(raw_bytes, encoding='utf-8')
            self.text_browser.setMarkdown(markdown_text)
        else:
            self.text_browser.setHtml(
                f"<p style='color: red;'><b>Failed to load content.</b><br>Error: {reply.errorString()}</p>"
            )
        reply.deleteLater()