Initial revision

Lib/formatter.py

@@ -0,0 +1,276 @@
+import regex
+import regsub
+import string
+import sys
+
+
+AS_IS = None
+
+whitespace = '[' + string.whitespace + ']+'
+
+
+class AbstractFormatter:
+
+    def __init__(self, writer):
+	self.writer = writer		# Output device
+	self.font_stack = []		# Font state
+	self.margin_stack = []		# Margin state
+	self.spacing = None		# Vertical spacing state
+	self.style_stack = []		# Other state, e.g. color
+	self.nospace = 1 # Should leading space be suppressed
+	self.softspace = 0 # Should a space be inserted
+
+    def end_paragraph(self, blankline):
+	if not self.nospace:
+	    self.writer.send_paragraph(blankline)
+	self.nospace = 1
+	self.softspace = 0
+
+    def add_line_break(self):
+	self.writer.send_line_break()
+	self.nospace = 1
+	self.softspace = 0
+
+    def add_hor_rule(self):
+	self.writer.send_hor_rule()
+	self.nospace = 1
+	self.softspace = 0
+
+    def add_label_data(self, format, counter):
+	data = self.format_counter(format, counter)
+	self.writer.send_label_data(data)
+
+    def format_counter(self, format, counter):
+	if counter <= 0:
+	    return format
+        label = ''
+        for c in format:
+            try:
+                if c == '1':
+		    c = '%d' % counter
+                elif c in 'aA':
+		    c = self.format_letter(c, counter)
+                elif c in 'iI':
+		    c = self.format_roman(c, counter)
+            except:
+                pass
+            label = label + c
+        return label
+
+    def format_letter(self, case, counter):
+	label = ''
+	while counter > 0:
+	    counter, x = divmod(counter-1, 26)
+	    s = chr(ord(case) + x)
+	    label = s + label
+	return label
+
+    def format_roman(self, case, counter):
+        ones = ['i', 'x', 'c', 'm']
+        fives = ['v', 'l', 'd']
+        label = ''
+        index = 0
+	# This will die of IndexError when counter is too big
+        while counter > 0:
+            counter, x = divmod(counter, 10)
+            if x == 9:
+                s = ones[index] + ones[index+1]
+            elif x == 4:
+                s = ones[index] + fives[index]
+            else:
+                if x >= 5:
+                    s = fives[index]
+                    x = x-5
+                else:
+                    s = ''
+                s = s + ones[index]*x
+            label = s + label
+            index = index + 1
+        if case == 'I': label = string.upper(label)
+        return label
+
+    def add_flowing_data(self, data):
+	if not data: return
+	data = regsub.gsub(whitespace, ' ', data)
+	if self.nospace and data[0] == ' ':
+	    data = data[1:]
+	    if not data: return
+	elif self.softspace and data[0] != ' ':
+	    data = ' ' + data
+	self.nospace = self.softspace = 0
+	if data[-1] == ' ':
+	    data = data[:-1]
+	    self.softspace = 1
+	self.writer.send_flowing_data(data)
+
+    def add_literal_data(self, data):
+	if self.softspace and data[:1] != '\n':
+	    data = ' ' + data
+	self.nospace = self.softspace = 0
+	self.writer.send_literal_data(data)
+
+    def push_font(self, (size, i, b, tt)):
+	if self.font_stack:
+	    csize, ci, cb, ctt = self.font_stack[-1]
+	    if size is AS_IS: size = csize
+	    if i is AS_IS: i = ci
+	    if b is AS_IS: b = cb
+	    if tt is AS_IS: tt = ctt
+	font = (size, i, b, tt)
+	self.font_stack.append(font)
+	self.writer.new_font(font)
+
+    def pop_font(self):
+	if self.font_stack:
+	    del self.font_stack[-1]
+	if self.font_stack:
+	    font = self.font_stack[-1]
+	else:
+	    font = None
+	self.writer.new_font(font)
+
+    def push_margin(self, margin):
+	self.margin_stack.append(margin)
+	self.writer.new_margin(margin, len(self.margin_stack))
+
+    def pop_margin(self):
+	if self.margin_stack:
+	    del self.margin_stack[-1]
+	if self.margin_stack:
+	    margin = self.margin_stack[-1]
+	else:
+	    margin = None
+	self.writer.new_margin(margin, len(self.margin_stack))
+
+    def set_spacing(self, spacing):
+	self.spacing = spacing
+	self.writer.new_spacing(spacing)
+
+    def push_style(self, style):
+	self.style_stack.append(style)
+	self.writer.new_styles(tuple(self.style_stack))
+
+    def pop_style(self):
+	if self.style_stack:
+	    del self.style_stack[-1]
+	self.writer.new_styles(tuple(self.style_stack))
+
+
+class AbstractWriter:
+
+    def __init__(self):
+	pass
+
+    def new_font(self, font):
+	print "new_font(%s)" % `font`
+
+    def new_margin(self, margin, level):
+	print "new_margin(%s, %d)" % (`margin`, level)
+
+    def new_spacing(self, spacing):
+	print "new_spacing(%s)" % `spacing`
+
+    def new_styles(self, styles):
+	print "new_styles(%s)" % `styles`
+
+    def send_paragraph(self, blankline):
+	print "send_paragraph(%s)" % `blankline`
+
+    def send_line_break(self):
+	print "send_line_break()"
+
+    def send_hor_rule(self):
+	print "send_hor_rule()"
+
+    def send_label_data(self, data):
+	print "send_label_data(%s)" % `data`
+
+    def send_flowing_data(self, data):
+	print "send_flowing_data(%s)" % `data`
+
+    def send_literal_data(self, data):
+	print "send_literal_data(%s)" % `data`
+
+
+class DumbWriter(AbstractWriter):
+
+    def __init__(self, file=None, maxcol=72):
+	self.file = file or sys.stdout
+	self.maxcol = maxcol
+	AbstractWriter.__init__(self)
+	self.reset()
+
+    def reset(self):
+	self.col = 0
+	self.atbreak = 0
+
+    def send_paragraph(self, blankline):
+	self.file.write('\n' + '\n'*blankline)
+	self.col = 0
+	self.atbreak = 0
+
+    def send_line_break(self):
+	self.file.write('\n')
+	self.col = 0
+	self.atbreak = 0
+
+    def send_hor_rule(self):
+	self.file.write('\n')
+	self.file.write('-'*self.maxcol)
+	self.file.write('\n')
+	self.col = 0
+	self.atbreak = 0
+
+    def send_literal_data(self, data):
+	self.file.write(data)
+	i = string.rfind(data, '\n')
+	if i >= 0:
+	    self.col = 0
+	    data = data[i+1:]
+	data = string.expandtabs(data)
+	self.col = self.col + len(data)
+	self.atbreak = 0
+
+    def send_flowing_data(self, data):
+	if not data: return
+	atbreak = self.atbreak or data[0] in string.whitespace
+	col = self.col
+	maxcol = self.maxcol
+	write = self.file.write
+	for word in string.split(data):
+	    if atbreak:
+		if col + len(word) >= maxcol:
+		    write('\n')
+		    col = 0
+		else:
+		    write(' ')
+		    col = col + 1
+	    write(word)
+	    col = col + len(word)
+	    atbreak = 1
+	self.col = col
+	self.atbreak = data[-1] in string.whitespace
+
+
+def test(file = None):
+    w = DumbWriter()
+    f = AbstractFormatter(w)
+    if file:
+	fp = open(file)
+    elif sys.argv[1:]:
+	fp = open(sys.argv[1])
+    else:
+	fp = sys.stdin
+    while 1:
+	line = fp.readline()
+	if not line:
+	    break
+	if line == '\n':
+	    f.end_paragraph(1)
+	else:
+	    f.add_flowing_data(line)
+    f.end_paragraph(0)
+
+
+if __name__ == '__main__':
+    test()