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Diffstat (limited to 'extensions/docbook.py')
| -rw-r--r-- | extensions/docbook.py | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/extensions/docbook.py b/extensions/docbook.py new file mode 100644 index 0000000..c070602 --- /dev/null +++ b/extensions/docbook.py @@ -0,0 +1,239 @@ +# docbook.py: extension module +# $Id: docbook.py 8353 2009-03-17 16:57:50Z mzjn $ + +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 |