#!/usr/bin/env python3

from textwrap import TextWrapper as wrap
from threading import Thread
import signal
from time import sleep, time
import os.path as path
from os.path import getmtime as gt
import curses
from curses import wrapper
import curses.textpad as textpad
import sys
import re


class Viewport:
    def __init__(self, screen):
        curses.curs_set(0)
        self.user_path = path.expanduser('~')
        self.username = path.split(self.user_path)[-1]
        self.screen = screen
        self.width = curses.COLS - 1
        self.height = curses.LINES - 1
        self.last_update = 0.0
        self.last_msg = ''
        self.update = False
        self.path = '/home/sloum/Documents/code/python/colorchat/chatlog'
        self.screen.nodelay(True)
        self.screen.clear()
        self.c_out = self.screen.subwin(self.height - 3, self.width,0,0)
        self.c_in = self.screen.subwin(3,self.width,self.height - 3,0)
        self.text_buffer = ''
        self.watcher = Thread(target=self.watch, args=(self.path,), daemon=True)
        self.main()


    def main(self):
        self.watcher.start()
        while True:
            self.text_input()
            if self.update:
                self.flash_log()
                self.update = False
            sleep(0.05)


    def watch(self,filepath):
        while True:
            filetime = gt(filepath)
            elapsedtime = self.elapsed_time(filetime)
            if elapsedtime:
                self.last_msg = elapsedtime
            if filetime > self.last_update:
                self.last_update = filetime
                self.update = True
            else:
                self.update = False
            sleep(0.5)


    def flash_log(self):
        with open(self.path, 'r') as f:
            temp = f.read()
        temp_list = self.wrap_text(temp)
        rows = len(temp_list)
        max_rows = self.height - 2
        self.c_out.erase()
        self.c_out.hline(0,0,'.',self.width)
        title = '_colorchat_'
        position = self.width // 2 - len(title) // 2
        self.c_out.addstr(0,position,title)
        if rows < max_rows:
            for x in range(rows - 1):
                self.c_out.addstr(max_rows - rows + x, 0, temp_list[x])
        else:
            counter = 1
            for x in temp_list[-(max_rows-2):]:
                self.c_out.addstr(counter, 0, x)
                counter += 1
        self.c_out.refresh()


    # takes in a string and outputs a list of strings
    def wrap_text(self, string):
        ob = wrap(width=self.width - 2, tabsize=4, replace_whitespace=False)
        text = [ob.fill(x) for x in string.split('\n')]
        text = '\n'.join(text).split('\n')
        return text


    def text_input(self):
        self.c_in.erase()
        c = self.screen.getch()
        if c in (curses.KEY_ENTER, 10, 13):
            self.send_msg()
        elif c == curses.KEY_BACKSPACE:
            if len(self.text_buffer) > 0:
                self.text_buffer = self.text_buffer[:-1]
        elif c != -1 and not c in [curses.KEY_UP, curses.KEY_LEFT, curses.KEY_DOWN, curses.KEY_RIGHT]:
            character = chr(c)
            if re.match(r'^[\S ]+$',character):
                self.text_buffer += chr(c)
        self.c_in.hline(0,0,'-',self.width)
        self.c_in.addstr(1,1,self.text_buffer[-(self.width * 2 - 10):] + '_')
        self.c_in.addstr(2,self.width - 1 - len(self.last_msg),self.last_msg)
        self.c_in.refresh()


    def send_msg(self):
        if self.text_buffer in ['q','quit','exit']:
            sys.exit(0)

        with open(self.path, 'a') as f:
            f.write('{} >  {}\n'.format(self.username,self.text_buffer))
        self.text_buffer = ''


    def elapsed_time(self,last_time):
        if not last_time:
            return False
        current = time()
        elapsed = int(current - last_time)
        unit = 's'
        if elapsed >= 60:
            elapsed = elapsed // 60
            unit = 'm'
            if elapsed >= 60:
                elapsed = elapsed // 60
                unit = 'h'
                if elapsed >= 24:
                    elapsed = elapsed // 24
                    unit = 'd'
        return 'Time since last post: {}{}'.format(elapsed,unit)


if __name__ == '__main__':
    signal.signal(signal.SIGINT,signal.SIG_IGN)
    try:
        wrapper(Viewport)
    except KeyboardInterrupt:
        curses.echo()
        curses.nocbreak()
        curses.endwin()
    finally:
        sys.exit(1)