#!/usr/local/bin/python
# tabview.py -- View a tab-delimited file in a spreadsheet-like display.
# Contributed by A.M. Kuchling <amk@amk.ca>
#
# The tab-delimited file is displayed on screen. The highlighted
# position is shown in the top-left corner of the screen; below it are
# shown the contents of that cell.
#
# Movement keys are:
# Cursor keys: Move the highlighted cell, scrolling if required.
# Q or q : Quit
# TAB : Page right a screen
# Home : Move to the start of this line
# End : Move to the end of this line
# PgUp/PgDn : Move a page up or down
# Insert : Memorize this position
# Delete : Return to memorized position (if any)
#
# TODO :
# A 'G' for Goto: enter a cell like AA260 and move there
# A key to re-read the tab-delimited file
#
# Possible projects:
# Allow editing of cells, and then saving the modified data
# Add formula evaluation, and you've got a simple spreadsheet
# program. (Actually, you should allow displaying both via curses and
# via a Tk widget.)
#
import curses, re, string
def yx2str(y,x):
"Convert a coordinate pair like 1,26 to AA2"
if x<26: s=chr(65+x)
else:
x=x-26
s=chr(65+ (x/26) ) + chr(65+ (x%26) )
s=s+str(y+1)
return s
coord_pat = re.compile('^(?P<x>[a-zA-Z]{1,2})(?P<y>\d+)$')
def str2yx(s):
"Convert a string like A1 to a coordinate pair like 0,0"
match = coord_pat.match(s)
if not match: return None
y,x = match.group('y', 'x')
x = string.upper(x)
if len(x)==1: x=ord(x)-65
else:
x= (ord(x[0])-65)*26 + ord(x[1])-65 + 26
return string.atoi(y)-1, x
assert yx2str(0,0) == 'A1'
assert yx2str(1,26) == 'AA2'
assert str2yx('AA2') == (1,26)
assert str2yx('B2') == (1,1)
class TabFile:
def __init__(self, scr, filename, column_width=20):
self.scr=scr ; self.filename = filename
self.column_width = column_width
f=open(filename, 'r')
self.data = []
while (1):
L=f.readline()
if L=="": break
self.data.append( string.split(L, '\t') )
# if len(self.data)>6: break # XXX
self.x, self.y = 0,0
self.win_x, self.win_y = 0,0
self.max_y, self.max_x = self.scr.getmaxyx()
self.num_columns = int(self.max_x/self.column_width)
self.scr.clear()
self.display()
def move_to_end(self):
"""Move the highlighted location to the end of the current line."""
# This is a method because I didn't want to have the code to
# handle the End key be aware of the internals of the TabFile object.
yp=self.y+self.win_y ; xp=self.x+self.win_x
if len(self.data)<=yp: end=0
else: end=len(self.data[yp])-1
# If the end column is on-screen, just change the
# .x value appropriately.
if self.win_x <= end < self.win_x + self.num_columns:
self.x = end - self.win_x
else:
if end<self.num_columns:
self.win_x = 0 ; self.x = end
else:
self.x = self.num_columns-1
self.win_x = end-self.x
def display(self):
"""Refresh the current display"""
self.scr.addstr(0,0,
yx2str(self.y + self.win_y, self.x+self.win_x)+' ',
curses.A_REVERSE)
for y in range(0, self.max_y-3):
self.scr.move(y+2,0) ; self.scr.clrtoeol()
for x in range(0, int(self.max_x / self.column_width) ):
self.scr.attrset(curses.A_NORMAL)
yp=y+self.win_y ; xp=x+self.win_x
if len(self.data)<=yp: s=""
elif len(self.data[yp])<=xp: s=""
else: s=self.data[yp][xp]
s = string.ljust(s, 15)[0:15]
if x==self.x and y==self.y: self.scr.attrset(curses.A_STANDOUT)
self.scr.addstr(y+2, x*self.column_width, s)
yp=self.y+self.win_y ; xp=self.x+self.win_x
if len(self.data)<=yp: s=""
elif len(self.data[yp])<=xp: s=""
else: s=self.data[yp][xp]
self.scr.move(1,0) ; self.scr.clrtoeol()
self.scr.addstr(s[0:self.max_x])
self.scr.refresh()
def main(stdscr):
import string, curses, sys
if len(sys.argv)==1:
print 'Usage: tabview.py <filename>'
return
filename=sys.argv[1]
# Clear the screen and display the menu of keys
stdscr.clear()
file = TabFile(stdscr, filename)
# Main loop:
while (1):
stdscr.move(file.y+2, file.x*file.column_width) # Move the cursor
c=stdscr.getch() # Get a keystroke
if 0<c<256:
c=chr(c)
# Q or q exits
if c in 'Qq': break
# Tab pages one screen to the right
elif c=='\t':
file.win_x = file.win_x + file.num_columns
file.display()
else: pass # Ignore incorrect keys
# Cursor keys
elif c==curses.key_up:
if file.y == 0:
if file.win_y>0: file.win_y = file.win_y - 1
else: file.y=file.y-1
file.display()
elif c==curses.key_down:
if file.y < file.max_y-3 -1: file.y=file.y+1
else: file.win_y = file.win_y+1
file.display()
elif c==curses.key_left:
if file.x == 0:
if file.win_x>0: file.win_x = file.win_x - 1
else: file.x=file.x-1
file.display()
elif c==curses.key_right:
if file.x < int(file.max_x/file.column_width)-1: file.x=file.x+1
else: file.win_x = file.win_x+1
file.display()
# Home key moves to the start of this line
elif c==curses.key_home:
file.win_x = file.x = 0
file.display()
# End key moves to the end of this line
elif c==curses.key_end:
file.move_to_end()
file.display()
# PageUp moves up a page
elif c==curses.key_ppage:
file.win_y = file.win_y - (file.max_y - 2)
if file.win_y<0: file.win_y = 0
file.display()
# PageDn moves down a page
elif c==curses.key_npage:
file.win_y = file.win_y + (file.max_y - 2)
if file.win_y<0: file.win_y = 0
file.display()
# Insert memorizes the current position
elif c==curses.key_ic:
file.save_y, file.save_x = file.y + file.win_y, file.x + file.win_x
# Delete restores a saved position
elif c==curses.key_dc:
if hasattr(file, 'save_y'):
file.x = file.y = 0
file.win_y, file.win_x = file.save_y, file.save_x
file.display()
else:
stdscr.addstr(0,50, curses.keyname(c)+ ' pressed')
stdscr.refresh()
pass # Ignore incorrect keys
if __name__=='__main__':
import curses, traceback
try:
# Initialize curses
stdscr=curses.initscr()
# Turn off echoing of keys, and enter cbreak mode,
# where no buffering is performed on keyboard input
curses.noecho() ; curses.cbreak()
# In keypad mode, escape sequences for special keys
# (like the cursor keys) will be interpreted and
# a special value like curses.key_left will be returned
stdscr.keypad(1)
main(stdscr) # Enter the main loop
# Set everything back to normal
stdscr.keypad(0)
curses.echo() ; curses.nocbreak()
curses.endwin() # Terminate curses
except:
# In the event of an error, restore the terminal
# to a sane state.
stdscr.keypad(0)
curses.echo() ; curses.nocbreak()
curses.endwin()
traceback.print_exc() # Print the exception
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