#!/usr/bin/python
import cgi, os, os.path, time, re

lockFileName = "files/todolock"
fileName = "files/todos.xml"

while(os.path.exists(lockFileName)):
    time.sleep(.25)

lockFileHandle = open(lockFileName, "w")
lockFileHandle.write("locked")
lockFileHandle.close()

form = cgi.FieldStorage()
catToUpdate = form.getfirst("category")
isUpMove = int(form.getfirst("isUp"))
#catToUpdate = "Pending"
#isUpMove = 0

oldFile = open(fileName, 'r')
oldFileLines = oldFile.readlines()
oldFile.close()

catStartRe = re.compile(r'^<category type="%s">' % catToUpdate)
catEndRe = re.compile(r'^</category>')
otherCatStartRe = re.compile(r'^<category type=')
lineIndex = 0
inCategory = False
haveFoundCategory = False
nextCategoryEndLine = -1
prevCategoryStartLine = -1
for line in oldFileLines:
    if (inCategory):
        if (catEndRe.match(line)):
            categoryEndLine = lineIndex
            inCategory = False
            haveFoundCategory = True
    else:
        if (catStartRe.match(line)):
            inCategory = True
            categoryStartLine = lineIndex
        else:
            if (not haveFoundCategory and otherCatStartRe.match(line)):
                prevCategoryStartLine = lineIndex
            elif (haveFoundCategory and catEndRe.match(line)):
                if (nextCategoryEndLine == -1):
                    nextCategoryEndLine = lineIndex
    lineIndex = lineIndex + 1

try:
    categoryLines = oldFileLines[categoryStartLine:categoryEndLine+1]
    if (isUpMove):
        if (prevCategoryStartLine != -1):
            # Insert lines before the prevCategoryStartLine line
            lineIndexToInsert = prevCategoryStartLine
            for line in categoryLines:
                oldFileLines.insert(lineIndexToInsert, line)
                lineIndexToInsert = lineIndexToInsert + 1
            numLinesAdded = lineIndexToInsert - prevCategoryStartLine
            lineIndexToDelete = categoryStartLine + numLinesAdded
    else:
        if (nextCategoryEndLine != -1):
            # Insert lines after the nextCategoryEndLine line
            lineIndexToInsert = nextCategoryEndLine + 1
            for line in categoryLines:
                oldFileLines.insert(lineIndexToInsert, line)
                lineIndexToInsert = lineIndexToInsert + 1
            numLinesAdded = lineIndexToInsert - (nextCategoryEndLine + 1)
            lineIndexToDelete = categoryStartLine
    del oldFileLines[lineIndexToDelete:lineIndexToDelete+numLinesAdded] 

    newFile = open(fileName, 'w')
    for line in oldFileLines:
        newFile.write(line)
    newFile.close()
finally:
    os.remove(lockFileName)

    print "Content-type: text/plain\n\n"
    print "done."