#    Copyright 2020 Romain de Laage
#
#    This file is part of tkGemini.
#
#    tkGemini 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
#    any later version.
#
#    tkGemini 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 tkGemini.  If not, see <https://www.gnu.org/licenses/>.

import tkinter as tk
import tkinter.messagebox
import tkinter.simpledialog
import gemini
import renderEngine
import urllib.parse

class Application():
    def __init__(self):
        # Some global definitions
        self.root = tk.Tk()
        self.nav_bar = NavBar(self)
        self.content = Content(self)
        self.current_URL = "about:home"

        # Set window title
        self.root.title("tkGemini")

        # App main loop
        self.root.mainloop()

    def updateContent(self):
        # Get url asked
        url=self.nav_bar.getURL()

        # Is it a Gemini URL
        if not(verifyURL(url)):
            tkinter.messagebox.showerror("URL error", url+" is not a correct Gemini URL ! (HTTP/S is not supported, please use a web browser instead)")
            return

        self.current_URL = self.nav_bar.getURL()

        # New request
        r = gemini.Request(self.current_URL)
        status = r.makeRequest()

        # The server asked for user input
        if status[0] == "1":
            user_input = tkinter.simpledialog.askstring("User input", "The server asked for " + r.meta + ".")
            self.nav_bar.URL_var.set(self.current_URL + "?" + user_input)
            self.updateContent()
        # If server asked for redirection
        elif status[0] == "3":
            # Ask to user
            confirm = tkinter.messagebox.askyesno("Server redirection", "This server ask for redirection to " + r.meta + ". Follow ?")
            # If he accepted
            if confirm:
                self.nav_bar.URL_var.set(r.meta)
                self.updateContent()
        # The server asked for client certificate, unsupported
        elif status[0] == "6":
            tkinter.messagebox.showerror("Client certificate required", "Error " + status + " : " + r.meta)
        else:
            self.content.setContent(r.content)

    def linkClick(self, url):
        # Check if it is an absolute URL
        if "://" in url:
            # Check if it is a gemini URL
            if verifyURL(url):
                self.nav_bar.URL_var.set(url)
                self.updateContent()
            # Else show error
            else:
                tkinter.messagebox.showerror("URL error", url+" is not a correct Gemini URL ! (HTTP/S is not supported, please use a web browser instead)")
        # It is relative
        else:
            # Join current URL and relative path
            base = self.current_URL
            base = base.replace("gemini://","http://")
            url = urllib.parse.urljoin(base, url)
            url = url.replace("http://", "gemini://")

            # We can verify because sometime there is errors (mailto:)
            if verifyURL(url):
                self.nav_bar.URL_var.set(url)
                self.updateContent()
            else:
                tkinter.messagebox.showerror("URL error", url+" is not a correct Gemini URL ! (HTTP/S is not supported, please use a web browser instead)")

def verifyURL(url):
    # Is it an absolute path ?
    if "://" in url:
        parsed_url = urllib.parse.urlparse(url)
        # Is this path supported ?
        if parsed_url.scheme == "gemini":
            return True
        else:
            return False

class NavBar():
    def __init__(self, parent):
        # Some global definitions
        self.parent = parent

        # All widgets are in a frame
        self.root = tk.Frame(self.parent.root)
        self.root.grid(column=0, row=0)

        # Define URL bar and variable
        self.URL_var = tk.StringVar()
        self.URL_bar = tk.Entry(self.root, textvariable=self.URL_var)
        self.URL_var.set("about:home")
        self.URL_bar.grid(column=0, row=0)

        # Define go button with action
        self.go_button = tk.Button(self.root, text='Go !', command=self.parent.updateContent)
        self.go_button.grid(column=1, row=0)

    def getURL(self):
        # Get URL from URL bar variable
        return self.URL_var.get()

class Content():
    def __init__(self, parent):
        self.parent = parent

        # Text container with home page
        self.root = renderEngine.Renderer(self.parent, "#Home page\nWelcome on tkGemini, a browser software for Gemini protocole\n=>gemini://rdelaage.ovh My gemini space")
        self.root.parse()
        self.root.content.grid(column=0, row=1)

        # Scrollbar beside to the text container
        self.scroll_bar = tk.Scrollbar(command=self.root.content.yview, orient='vertical')
        self.scroll_bar.grid(column=1, row=1)
        self.root.content['yscrollcommand'] = self.scroll_bar.set

    # When content is updated
    def setContent(self, new_content):
        self.root.text = new_content
        self.root.parse()

app = Application()