#! /usr/bin/python2
 #
 #    Copyright (C) 2015 vmware inc.
 #
 #    Author: Mahmoud Bassiouny <mbassiouny@vmware.com>
 
 import curses
 from actionresult import ActionResult
 from action import Action
 
 class TextPane(Action):
     def __init__(self, starty, maxx, width, text_file_path, height, menu_items):
         self.head_position = 0  #This is the start of showing
         self.menu_position = 0
         self.lines = []
         self.menu_items = menu_items;
 
         self.width = width
         
         self.read_file(text_file_path, self.width - 3);
 
         self.num_items = len(self.lines)
         self.text_height = height - 2
 
         # Check if we need to add a scroll bar
         if self.num_items > self.text_height:
             self.show_scroll = True
         else:
             self.show_scroll = False
 
         # Some calculation to detitmine the size of the scroll filled portion
         self.filled = int(round(self.text_height * self.text_height / float(self.num_items)))
         if self.filled == 0:
             self.filled += 1
         for i in [1, 2]:
             if (self.num_items - self.text_height) >= i and (self.text_height - self.filled) == (i - 1):
                 self.filled -= 1
 
         self.window = curses.newwin(height, self.width)
         self.window.bkgd(' ', curses.color_pair(2))
 
         self.window.keypad(1)
         self.panel = curses.panel.new_panel(self.window)
 
         self.panel.move(starty, (maxx - self.width) / 2)
         self.panel.hide()
         curses.panel.update_panels()
 
     def read_file(self, text_file_path, line_width):
         with open(text_file_path, "r") as f:
             for line in f:
                 # remove the trailing line feeds
                 while line.endswith('\r') or line.endswith('\n'):
                     line = line[:-1]
                 # Adjust the words on the lines
                 while len(line) > line_width:
                     sep_index = line_width

 
                     while sep_index > 0 and line[sep_index-1] != ' ' and line[sep_index] != ' ':

                         sep_index = sep_index - 1

 
                     current_line_width=sep_index
                     if sep_index == 0:
                         current_line_width = line_width
                     currLine = line[:current_line_width]
                     line = line.strip()
                     line = line[current_line_width:]

 
                     # Lengthen the line with spaces
                     self.lines.append(currLine + ' ' * (line_width - len(currLine)))
 
                 # lengthen the line with spaces
                 self.lines.append(line + ' ' * (line_width - len(line)))
 
     def navigate(self, n):
         self.head_position += n
         if self.head_position < 0:
             self.head_position = 0
         elif self.head_position > (len(self.lines) - self.text_height + 1):
             self.head_position = len(self.lines) - self.text_height + 1
 
     def navigate_menu(self, n):
         self.menu_position += n
         if self.menu_position < 0:
             self.menu_position = 0
         elif self.menu_position >= len(self.menu_items):
             self.menu_position = len(self.menu_items) - 1
 
 
     def render_scroll_bar(self):
         if self.show_scroll:
             remaining_above = self.head_position
             remaining_down = self.num_items - self.text_height - self.head_position#
             
             up = int(round(remaining_above * self.text_height / float(self.num_items)))
             down = self.text_height - up - self.filled
 
             if up == 0 and remaining_above > 0:
                 up += 1
                 down -= 1
             if down == 0 and remaining_down > 0:
                 up -= 1
                 down += 1
             if remaining_down == 0 and down != 0:
                 up += down
                 down = 0
 
 
             for index in range(up):
                 self.window.addch(index, self.width - 2, curses.ACS_CKBOARD)
 
             for index in range(self.filled):
                 self.window.addstr(index + up, self.width - 2, ' ', curses.A_REVERSE)
 
             for index in range(down):
                 self.window.addch(index + up + self.filled, self.width - 2, curses.ACS_CKBOARD)
 
     def refresh(self):
         self.window.clear()
         for index, line in enumerate(self.lines):
             if (index < self.head_position):
                 continue
             elif (index > self.head_position + self.text_height - 1):
                 continue
 
             x = 0
             y = index - self.head_position
             if len(line) > 0:
                 self.window.addstr(y, x, line)
 
         xpos = self.width
         for index, item in enumerate(self.menu_items):
             if index == self.menu_position:
                 mode = curses.color_pair(3)
             else:
                 mode = curses.color_pair(2)
 
             self.window.addstr(self.text_height + 1, xpos - len(item[0]) - 4, item[0], mode)
             xpos = xpos - len(item[0]) - 4
 
         self.render_scroll_bar()
 
         self.window.refresh()
         self.panel.top()
         self.panel.show()
         curses.panel.update_panels()
         curses.doupdate()
 
     def hide(self):
         self.panel.hide()
         curses.panel.update_panels()
         curses.doupdate()
 
     def do_action(self):
         while True:
             self.refresh()
 
             key = self.window.getch()
 
             if key in [curses.KEY_ENTER, ord('\n')]:
                 self.hide()
                 return self.menu_items[self.menu_position][1]()
 
             if key == curses.KEY_UP:
                 self.navigate(-1)
             elif key == curses.KEY_DOWN:
                 self.navigate(1)
 
             elif key == curses.KEY_LEFT:
                 self.navigate_menu(1)
             elif key == curses.KEY_RIGHT:
                 self.navigate_menu(-1)
 
             elif key == curses.KEY_NPAGE:
                 self.navigate(self.text_height)
             elif key == curses.KEY_PPAGE:
                 self.navigate(-self.text_height)
 
             elif key == curses.KEY_HOME:
                 self.head_position = 0