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         if options.min_size != 'auto':
  17             raise Exception, 'curses UI supports only --min-size=auto'
  18         self._set_path(args[0])
  19         self._init_curses()
  20
  21     def _init_curses(self):
  22         curses.use_default_colors()
  23         curses.start_color()
  24         curses.curs_set(0)
  25
  26         def dots(*positions):
  27             return sum(map(lambda n: 1<<n, positions))
  28
  29         self.MATRIX_TO_CURSES = {
  30             dots(): ' ',
  31             dots(3, 4, 5): curses.ACS_HLINE,
  32             dots(1, 4, 7): curses.ACS_VLINE,
  33             dots(1, 3, 4, 5, 7): curses.ACS_PLUS,
  34             dots(4, 5, 7): curses.ACS_ULCORNER,
  35             dots(3, 4, 7): curses.ACS_URCORNER,
  36             dots(1, 4, 5): curses.ACS_LLCORNER,
  37             dots(1, 3, 4): curses.ACS_LRCORNER,
  38             dots(3, 4, 5, 7): curses.ACS_TTEE,
  39             dots(1, 3, 4, 5): curses.ACS_BTEE,
  40             dots(1, 4, 5, 7): curses.ACS_LTEE,
  41             dots(1, 3, 4, 7): curses.ACS_RTEE
  42         }
  43
  44         try:
  45             self.status_win = curses.newwin(0, 0)
  46             self.panel = curses.newwin(0, 0)
  47             self._resize()
  48         except curses.error:
  49             print 'Cannot create windows'
  50             sys.exit(1)
  51
  52     def _resize(self):
  53         """Called when the terminal size changes."""
  54         self.height, self.width = self.window.getmaxyx()
  55         self.height -= 1 # Status bar
  56         self.need_tree = True
  57         self.status_win.resize(1, self.width)
  58         self.status_win.mvwin(self.height, 0)
  59         self.panel.resize(self.height, self.width)
  60         self._set_path(self.path)
  61         self._refresh()
  62
  63     def _redraw(self):
  64         self.window.refresh()
  65         if self.need_tree:
  66             self.tree = pysize_tree(self.path, self.max_depth,
  67                                     3.0 / self.height)
  68             self.need_tree = False
  69         if not self.tree.root:
  70             return
  71         self.panel.erase()
  72
  73         self._draw_matrix(CharMatrix(self.width, self.height, self.tree,
  74                                      self.selected_node))
  75
  76         self.panel.refresh()
  77         self.status_win.erase()
  78         self.status_win.hline(0, 0, ord(' ') | curses.A_REVERSE, self.width)
  79         END = ' - Pysize'
  80         status_line = self.path + ' ' + human_unit(self.tree.root.size)
  81         if len(status_line) + len(END) >= self.width:
  82             status_line = short_string(status_line, self.width - 1)
  83         else:
  84             status_line += END
  85         self.status_win.addstr(status_line, curses.A_REVERSE)
  86         self.status_win.refresh()
  87
  88     def _refresh(self):
  89         while True:
  90             try:
  91                 self._redraw()
  92                 break
  93             except curses.error, e:
  94                 print e
  95                 time.sleep(1)
  96
  97     def _set_path(self, path):
  98         self.selected_node = None
  99         self.selection = None
 100         self.path = path
 101         self.need_tree = True
 102
 103     def _next_step(self):
 104         sequel = self.selected_node.get_fullpath()[len(self.path) + 1:]
 105         sequel = sequel.split('/', 1)[0]
 106         self._set_path(os.path.join(self.path, sequel))
 107
 108     def _select(self, function):
 109         if not self.selected_node:
 110             if self.tree.root.get_children():
 111                 self.selected_node = self.tree.root.get_children()[0]
 112             return
 113         selected = function(self.selected_node)
 114         if not selected:
 115             if function == self.tree.get_first_child and \
 116                     self.selected_node.is_dir():
 117                 # Browsing to the right
 118                 self._next_step()
 119             return
 120         self.selected_node = selected
 121         if self.selected_node == self.tree.root:
 122             # Browsing to the left
 123             if len(self.path) > 1:
 124                 parent = os.path.dirname(self.path)
 125                 self._set_path(parent)
 126             else:
 127                 self.selected_node = None
 128
 129     def _selected(self):
 130         if self.selected_node and self.selected_node.is_dir():
 131             self._set_path(self.selected_node.get_fullpath())
 132
 133     def run(self):
 134         """The main dispatcher."""
 135         key_bindings = {
 136             ord('q'): lambda:
 137                 sys.exit(0),
 138
 139             curses.KEY_RESIZE: lambda:
 140                 self._resize(),
 141
 142             curses.KEY_DOWN: lambda:
 143                 self._select(self.tree.get_next_sibling),
 144
 145             curses.KEY_UP: lambda:
 146                 self._select(self.tree.get_previous_sibling),
 147
 148             curses.KEY_LEFT: lambda:
 149                 self._select(self.tree.get_parent),
 150
 151             curses.KEY_RIGHT: lambda:
 152                 self._select(self.tree.get_first_child),
 153
 154             ord('\n'): lambda:
 155                 self._selected()
 156         }
 157
 158         while True:
 159             self._refresh()
 160             c = self.window.getch()
 161             action = key_bindings.get(c, lambda: None)
 162             action()
 163
 164     def _draw_matrix(self, matrix):
 165         for (y, line) in enumerate(matrix.matrix):
 166             for (x, char) in enumerate(line):
 167                 if isinstance(char, int):
 168                     selected = (char & SELECTED) != 0
 169                     char &= MASK
 170                     char = self.MATRIX_TO_CURSES[char]
 171                     if selected:
 172                         char |= curses.A_REVERSE
 173                     self.panel.insch(y, x, char)
 174                 else:
 175                     try:
 176                         char = char.encode('UTF-8')
 177                     except UnicodeDecodeError:
 178                         pass
 179                     self.panel.insstr(y, x, char)
 180
 181 def _run_curses(win, options, args):
 182     app = _CursesApp(win, options, args)
 183     app.run()
 184
 185 def run(options, args):
 186     locale.setlocale(locale.LC_ALL, '')
 187     curses.wrapper(_run_curses, options, args)
 188
 189 def is_available():
 190     return sys.stdin.isatty() and sys.stdout.isatty()