# Widget to display a man page

import regex
from Tkinter import *
from ScrolledText import ScrolledText

# XXX These fonts may have to be changed to match your system
BOLDFONT = '*-Courier-Bold-R-Normal-*-120-*'
ITALICFONT = '*-Courier-Medium-O-Normal-*-120-*'

# XXX Recognizing footers is system dependent
# (This one works for IRIX 5.2 and Solaris 2.2)
footerprog = regex.compile(
	'^     Page [1-9][0-9]*[ \t]+\|^.*Last change:.*[1-9][0-9]*\n')
emptyprog = regex.compile('^[ \t]*\n')
ulprog = regex.compile('^[ \t]*[Xv!_][Xv!_ \t]*\n')

# Basic Man Page class -- does not disable editing
class EditableManPage(ScrolledText):

	def __init__(self, master=None, cnf={}):
		# Initialize base class
		ScrolledText.__init__(self, master, cnf)

		# Define tags for formatting styles
		self.tag_config('X', {'font': BOLDFONT})
		self.tag_config('!', {'font': ITALICFONT})
		self.tag_config('_', {'underline': 1})

	def parsefile(self, fp):
		if hasattr(self, 'buffer'):
			raise RuntimeError, 'Still busy parsing!'
		from select import select
		def avail(fp=fp, tout=0.0, select=select):
			return select([fp], [], [], tout)[0]
		height = self.getint(self['height'])
		self.startparser()
		while 1:
			if self.lineno < height or \
			   self.lineno%10 == 0 or not avail():
				self.update()
			nextline = fp.readline()
			if not nextline:
				break
			self.parseline(nextline)
		self.endparser()
		self.update()

	def startparser(self):
		self.lineno = 0
		self.ok = 0
		self.empty = 0
		self.buffer = None

	def endparser(self):
		if self.buffer:
			self.parseline('')
		del self.ok, self.empty, self.buffer

	def parseline(self, nextline):
		if not self.buffer:
			# Save this line -- we need one line read-ahead
			self.buffer = nextline
			return
		if emptyprog.match(self.buffer) >= 0:
			# Buffered line was empty -- set a flag
			self.empty = 1
			self.buffer = nextline
			return
		textline = self.buffer
		if ulprog.match(nextline) >= 0:
			# Next line is properties for buffered line
			propline = nextline
			self.buffer = None
		else:
			# Next line is read-ahead
			propline = None
			self.buffer = nextline
		if not self.ok:
			# First non blank line after footer must be header
			# -- skip that too
			self.ok = 1
			self.empty = 0
			return
		if footerprog.match(textline) >= 0:
			# Footer -- start skipping until next non-blank line
			self.ok = 0
			self.empty = 0
			return
		if self.empty:
			# One or more previous lines were empty
			# -- insert one blank line in the text
			self.insert_prop('\n')
			self.lineno = self.lineno + 1
			self.empty = 0
		if not propline:
			# No properties
			self.insert_prop(textline)
			self.lineno = self.lineno + 1
			return
		# Search for properties
		p = ''
		j = 0
		for i in range(min(len(propline), len(textline))):
			if propline[i] != p:
				if j < i:
					self.insert_prop(textline[j:i], p)
					j = i
				p = propline[i]
		self.insert_prop(textline[j:])
		self.lineno = self.lineno + 1

	def insert_prop(self, str, prop = ' '):
		here = self.index('end')
		self.insert('end', str[0])
		tags = self.tag_names(here)
		for tag in tags:
			self.tag_remove(tag, here)
		if prop != ' ':
			self.tag_add(prop, here)
		self.insert('end', str[1:])

# Readonly Man Page class -- disables editing, otherwise the same
class ReadonlyManPage(EditableManPage):

	def __init__(self, master=None, cnf={}):
		# Initialize base class
		EditableManPage.__init__(self, master, cnf)

		# Make the text readonly
		self.bind('<Any-KeyPress>', self.modify_cb)
		self.bind('<Return>', self.modify_cb)
		self.bind('<BackSpace>', self.modify_cb)
		self.bind('<Delete>', self.modify_cb)
		self.bind('<Control-h>', self.modify_cb)
		self.bind('<Control-d>', self.modify_cb)
		self.bind('<Control-v>', self.modify_cb)

	def modify_cb(self, e):
		pass

# Alias
ManPage = ReadonlyManPage

# Test program.
# usage: ManPage [manpage]; or ManPage [-f] file
# -f means that the file is nroff -man output run through ul -i
def test():
	import os
	import sys
	# XXX This directory may be different on your system
	MANDIR = '/usr/local/man/mann'
	DEFAULTPAGE = 'Tcl'
	formatted = 0
	if sys.argv[1:] and sys.argv[1] == '-f':
		formatted = 1
		del sys.argv[1]
	if sys.argv[1:]:
		name = sys.argv[1]
	else:
		name = DEFAULTPAGE
	if not formatted:
		if name[-2:-1] != '.':
			name = name + '.n'
		name = os.path.join(MANDIR, name)
	root = Tk()
	root.minsize(1, 1)
	manpage = ManPage(root, {'relief': 'sunken', 'bd': 2,
				 Pack: {'expand': 1, 'fill': 'both'}})
	if formatted:
		fp = open(name, 'r')
	else:
		fp = os.popen('nroff -man %s | ul -i' % name, 'r')
	manpage.parsefile(fp)
	root.mainloop()

# Run the test program when called as a script
if __name__ == '__main__':
	test()