#!/usr/bin/env python3

#TODO: make sure things dont explode no matter what terminal size
# x prevent linebreaks in a single story
# x only load as many stories as fit
# -> refresh on resize

import requests
from bs4 import BeautifulSoup as Soup
import curses
import webbrowser

import api

spinner_states = ['-', '\\', '|', '/']

class Client:
    def __init__(self):
        # set up curses
        self.screen = curses.initscr()
        curses.noecho()
        curses.cbreak()
        self.screen.keypad(True)

        self.topstories = api.get_topstories()
        self.loadedstories = []
        self.story_pos = 0
        self.cursor_pos = 0
        self.lines = curses.LINES
        self.cols = curses.COLS
        self.stories_in_a_site = self.lines - 3

    def load_stories(self, from_pos, to_pos):
        for idx, i in enumerate(self.topstories[from_pos:to_pos]):
            #stdscr.clear()
            self.set_footer(f'[{spinner_states[idx%4]}] Loading stories...')
            self.screen.refresh()
            self.loadedstories.append(api.get_story(i))

    def set_footer(self, footer):
        self.screen.addstr(curses.LINES - 1, 0, footer, curses.A_REVERSE)

    def draw(self):

        self.screen.clear()
        self.lines = curses.LINES
        self.cols = curses.COLS
        # header, detail, footer:
        self.stories_in_a_site = self.lines - 3

        self.screen.addstr('Hacker News Top Stories:\n')
        for i, story in enumerate(self.loadedstories[self.story_pos:self.story_pos + self.stories_in_a_site]):
            prefix = '>>> ' if i == self.cursor_pos else '   '
            # calculate length of line
            text = f'{prefix} ()\n'
            chars_available = self.cols - len(text)
            max_title_len = min((chars_available//3)*2, len(story.title))
            max_url_len = chars_available - max_title_len

            title = story.title[:max_title_len-1] + "…" if len(story.title) > max_title_len else story.title
            link = story.link.replace('https://', '').replace('http://', '')
            link = link[:max_url_len-1] + "…" if len(link) > max_url_len else link

            text = '{}{} ({})\n'.format(prefix, title, link.replace('https://', '').replace('http://', ''))
            self.screen.addstr(text)
            if i == self.cursor_pos:
                detail = f'    by {story.author} | {story.comments} comments | {story.votes} points\n'
                self.screen.addstr(detail)
        self.set_footer(f'Loaded {self.stories_in_a_site} stories.')

    def handle_input(self):
        c = self.screen.getch()
        if c == ord('q'):  # Quit
            self.exit()
        elif c == curses.KEY_UP:
            self.cursor_pos -= 1
            if self.cursor_pos < 0:
                self.cursor_pos = self.stories_in_a_site-1
        elif c == curses.KEY_DOWN:
            self.cursor_pos += 1
            if self.cursor_pos >= self.stories_in_a_site:
                self.cursor_pos = 0
        elif c == ord('c'):
            webbrowser.open(f'https://news.ycombinator.com/item?id={self.loadedstories[self.story_pos + self.cursor_pos].id}')
        elif c == curses.KEY_ENTER or c == 10:
            webbrowser.open(self.loadedstories[self.story_pos + self.cursor_pos].link)
        elif c == curses.KEY_RESIZE:
            curses.resize_term(*self.screen.getmaxyx())
            self.lines, self.cols = self.screen.getmaxyx()
            self.stories_in_a_site = self.lines - 3

    def run(self):
        self.load_stories(0, self.stories_in_a_site)
        while True:
            self.draw()
            self.handle_input()

    def exit(self):
        curses.endwin()
        import sys
        sys.exit(0)

def main():
    try:
        client = Client()
        client.run()
    except Exception as e:
        curses.endwin()
        print(e)

if __name__ == '__main__':
    main()