# docbook.py: extension module
import sys
import string
import libxml2
import libxslt
import re
import math
# Some globals
pixelsPerInch = 96.0
unitHash = { 'in': pixelsPerInch,
'cm': pixelsPerInch / 2.54,
'mm': pixelsPerInch / 25.4,
'pc': (pixelsPerInch / 72.0) * 12,
'pt': pixelsPerInch / 72.0,
'px': 1 }
# ======================================================================
def adjustColumnWidths(ctx, nodeset):
#
# Small check to verify the context is correcly accessed
#
try:
pctxt = libxslt.xpathParserContext(_obj=ctx)
ctxt = pctxt.context()
tctxt = ctxt.transformContext()
except:
pass
# Get the nominal table width
varString = lookupVariable(tctxt, "nominal.table.width", None)
if varString == None:
nominalWidth = 6 * pixelsPerInch;
else:
nominalWidth = convertLength(varString);
# Get the requested table width
tableWidth = lookupVariable(tctxt, "table.width", "100%")
foStylesheet = (tctxt.variableLookup("stylesheet.result.type", None) == "fo")
relTotal = 0
relParts = []
absTotal = 0
absParts = []
colgroup = libxml2.xmlNode(_obj = nodeset[0])
# If this is an foStylesheet, we've been passed a list of fo:table-columns.
# Otherwise we've been passed a colgroup that contains a list of cols.
if foStylesheet:
colChildren = colgroup
else:
colChildren = colgroup.children
col = colChildren
while col != None:
if foStylesheet:
width = col.prop("column-width")
else:
width = col.prop("width")
if width == None:
width = "1*"
relPart = 0.0
absPart = 0.0
starPos = string.find(width, "*")
if starPos >= 0:
relPart, absPart = string.split(width, "*", 2)
relPart = float(relPart)
relTotal = relTotal + float(relPart)
else:
absPart = width
pixels = convertLength(absPart)
absTotal = absTotal + pixels
relParts.append(relPart)
absParts.append(pixels)
col = col.next
# Ok, now we have the relative widths and absolute widths in
# two parallel arrays.
#
# - If there are no relative widths, output the absolute widths
# - If there are no absolute widths, output the relative widths
# - If there are a mixture of relative and absolute widths,
# - If the table width is absolute, turn these all into absolute
# widths.
# - If the table width is relative, turn these all into absolute
# widths in the nominalWidth and then turn them back into
# percentages.
widths = []
if relTotal == 0:
for absPart in absParts:
if foStylesheet:
inches = absPart / pixelsPerInch
widths.append("%4.2fin" % inches)
else:
widths.append("%d" % absPart)
elif absTotal == 0:
for relPart in relParts:
rel = relPart / relTotal * 100
widths.append(rel)
widths = correctRoundingError(widths)
else:
pixelWidth = nominalWidth
if string.find(tableWidth, "%") < 0:
pixelWidth = convertLength(tableWidth)
if pixelWidth <= absTotal:
print "Table is wider than table width"
else:
pixelWidth = pixelWidth - absTotal
absTotal = 0
for count in range(len(relParts)):
rel = relParts[count] / relTotal * pixelWidth
relParts[count] = rel + absParts[count]
absTotal = absTotal + rel + absParts[count]
if string.find(tableWidth, "%") < 0:
for count in range(len(relParts)):
if foStylesheet:
pixels = relParts[count]
inches = pixels / pixelsPerInch
widths.append("%4.2fin" % inches)
else:
widths.append(relParts[count])
else:
for count in range(len(relParts)):
rel = relParts[count] / absTotal * 100
widths.append(rel)
widths = correctRoundingError(widths)
# Danger, Will Robinson! In-place modification of the result tree!
# Side-effect free? We don' need no steenkin' side-effect free!
count = 0
col = colChildren
while col != None:
if foStylesheet:
col.setProp("column-width", widths[count])
else:
col.setProp("width", widths[count])
count = count+1
col = col.next
return nodeset
def convertLength(length):
# Given "3.4in" return the width in pixels
global pixelsPerInch
global unitHash
m = re.search('([+-]?[\d\.]+)(\S+)', length)
if m != None and m.lastindex > 1:
unit = pixelsPerInch
if unitHash.has_key(m.group(2)):
unit = unitHash[m.group(2)]
else:
print "Unrecognized length: " + m.group(2)
pixels = unit * float(m.group(1))
else:
pixels = 0
return pixels
def correctRoundingError(floatWidths):
# The widths are currently floating point numbers, we have to truncate
# them back to integers and then distribute the error so that they sum
# to exactly 100%.
totalWidth = 0
widths = []
for width in floatWidths:
width = math.floor(width)
widths.append(width)
totalWidth = totalWidth + math.floor(width)
totalError = 100 - totalWidth
columnError = totalError / len(widths)
error = 0
for count in range(len(widths)):
width = widths[count]
error = error + columnError
if error >= 1.0:
adj = math.floor(error)
error = error - adj
widths[count] = "%d%%" % (width + adj)
else:
widths[count] = "%d%%" % width
return widths
def lookupVariable(tctxt, varName, default):
varString = tctxt.variableLookup(varName, None)
if varString == None:
return default
# If it's a list, get the first element
if type(varString) == type([]):
varString = varString[0]
# If it's not a string, it must be a node, get its content
if type(varString) != type(""):
varString = varString.content
return varString
# ======================================================================
# Random notes...
#once you have a node which is a libxml2 python xmlNode wrapper all common
#operations are possible:
# .children .last .parent .next .prev .doc for navigation
# .content .type for introspection
# .prop("attribute_name") to lookup attribute values
# # Now make a nodeset to return
# # Danger, Will Robinson! This creates a memory leak!
# newDoc = libxml2.newDoc("1.0")
# newColGroup = newDoc.newDocNode(None, "colgroup", None)
# newDoc.addChild(newColGroup)
# col = colgroup.children
# while col != None:
# newCol = newDoc.newDocNode(None, "col", None)
# newCol.copyPropList(col);
# newCol.setProp("width", "4")
# newColGroup.addChild(newCol)
# col = col.next