ui/curses/ui_curses.py

   1 import curses
   2 import os
   3 import sys
   4 import time
   5 import locale
   6
   7 from ui.utils import human_unit, short_string
   8 from ui.char_matrix import CharMatrix, MASK, SELECTED
   9 from core.pysize_fs_tree import pysize_tree
  10
  11 class _CursesApp:
  12     """The curses UI."""
  13     def __init__(self, win, options, args):
  14         self.window = win
  15         self.max_depth = options.max_depth
  16         self.root_path = args[0]
  17         self._set_path(self.root_path)
  18         self._init_curses()
  19
  20     def _init_curses(self):
  21         curses.use_default_colors()
  22         curses.start_color()
  23         curses.curs_set(0)
  24
  25         def dots(*positions):
  26             return sum(map(lambda n: 1<<n, positions))
  27
  28         self.MATRIX_TO_CURSES = {
  29             dots(): ' ',
  30             dots(3, 4, 5): curses.ACS_HLINE,
  31             dots(1, 4, 7): curses.ACS_VLINE,
  32             dots(1, 3, 4, 5, 7): curses.ACS_PLUS,
  33             dots(4, 5, 7): curses.ACS_ULCORNER,
  34             dots(3, 4, 7): curses.ACS_URCORNER,
  35             dots(1, 4, 5): curses.ACS_LLCORNER,
  36             dots(1, 3, 4): curses.ACS_LRCORNER,
  37             dots(3, 4, 5, 7): curses.ACS_TTEE,
  38             dots(1, 3, 4, 5): curses.ACS_BTEE,
  39             dots(1, 4, 5, 7): curses.ACS_LTEE,
  40             dots(1, 3, 4, 7): curses.ACS_RTEE
  41         }
  42
  43         try:
  44             self.status_win = curses.newwin(0, 0)
  45             self.panel = curses.newwin(0, 0)
  46             self._resize()
  47         except curses.error:
  48             print 'Cannot create windows'
  49             sys.exit(1)
  50
  51     def _resize(self):
  52         """Called when the terminal size changes."""
  53         self.height, self.width = self.window.getmaxyx()
  54         self.height -= 1 # Status bar
  55         self.need_tree = True
  56         self.status_win.resize(1, self.width)
  57         self.status_win.mvwin(self.height, 0)
  58         self.panel.resize(self.height, self.width)
  59         self._set_path(self.path)
  60         self._refresh()
  61
  62     def _redraw(self):
  63         self.window.refresh()
  64         if self.need_tree:
  65             self.tree = pysize_tree(self.path, self.max_depth,
  66                                     1.0 / self.height)
  67             self.need_tree = False
  68         if not self.tree.root:
  69             return
  70         self.panel.erase()
  71
  72         self._draw_matrix(CharMatrix(self.width, self.height, self.tree,
  73                                      self.selected_item))
  74
  75         self.panel.refresh()
  76         self.status_win.erase()
  77         self.status_win.hline(0, 0, ord(' ') | curses.A_REVERSE, self.width)
  78         END = ' - Pysize'
  79         status_line = self.path + ' ' + human_unit(self.tree.root.size)
  80         if len(status_line) + len(END) >= self.width:
  81             status_line = short_string(status_line, self.width - 1)
  82         else:
  83             status_line += END
  84         self.status_win.addstr(status_line, curses.A_REVERSE)
  85         self.status_win.refresh()
  86
  87     def _refresh(self):
  88         while True:
  89             try:
  90                 self._redraw()
  91                 break
  92             except curses.error, e:
  93                 print e
  94                 time.sleep(1)
  95
  96     def _set_path(self, path):
  97         self.selected_item = None
  98         self.selection = None
  99         self.path = path
 100         self.need_tree = True
 101
 102     def _next_step(self):
 103         sequel = self.selected_item.get_fullpath()[len(self.path) + 1:]
 104         sequel = sequel.split('/', 1)[0]
 105         self._set_path(os.path.join(self.path, sequel))
 106
 107     def _select(self, function):
 108         if not self.selected_item:
 109             if self.tree.root.get_children():
 110                 self.selected_item = self.tree.root.get_children()[0]
 111             return
 112         selected = function(self.selected_item)
 113         if not selected:
 114             if function == self.tree.get_first_child and \
 115                     self.selected_item.is_dir():
 116                 # Browsing to the right
 117                 self._next_step()
 118             return
 119         self.selected_item = selected
 120         if self.selected_item is self.tree.root:
 121             # Browsing to the left
 122             if not os.path.samefile(self.path, self.root_path):
 123                 parent = os.path.dirname(self.selected_item.get_fullpath())
 124                 self._set_path(parent)
 125             else:
 126                 self.selected_item = None
 127
 128     def _selected(self):
 129         if self.selected_item and self.selected_item.is_dir():
 130             self._set_path(self.selected_item.get_fullpath())
 131
 132     def run(self):
 133         """The main dispatcher."""
 134         key_bindings = {
 135             ord('q'): lambda:
 136                 sys.exit(0),
 137
 138             curses.KEY_RESIZE: lambda:
 139                 self._resize(),
 140
 141             curses.KEY_DOWN: lambda:
 142                 self._select(self.tree.get_next_sibling),
 143
 144             curses.KEY_UP: lambda:
 145                 self._select(self.tree.get_previous_sibling),
 146
 147             curses.KEY_LEFT: lambda:
 148                 self._select(self.tree.get_parent),
 149
 150             curses.KEY_RIGHT: lambda:
 151                 self._select(self.tree.get_first_child),
 152
 153             ord('\n'): lambda:
 154                 self._selected()
 155         }
 156
 157         while True:
 158             self._refresh()
 159             c = self.window.getch()
 160             action = key_bindings.get(c, lambda: None)
 161             action()
 162
 163     def _draw_matrix(self, matrix):
 164         for (y, line) in enumerate(matrix.matrix):
 165             for (x, char) in enumerate(line):
 166                 if isinstance(char, int):
 167                     selected = (char & SELECTED) != 0
 168                     char &= MASK
 169                     char = self.MATRIX_TO_CURSES[char]
 170                     if selected:
 171                         char |= curses.A_REVERSE
 172                     self.panel.insch(y, x, char)
 173                 else:
 174                     char = char.encode('UTF-8')
 175                     self.panel.insstr(y, x, char)
 176
 177 def _run_curses(win, options, args):
 178     app = _CursesApp(win, options, args)
 179     app.run()
 180
 181 def run(options, args):
 182     locale.setlocale(locale.LC_ALL, '')
 183     curses.wrapper(_run_curses, options, args)
 184
 185 def is_available():
 186     return sys.stdin.isatty() and sys.stdout.isatty()