Some cleanup

[frenchie/icalparse.git] / icalparse.py

diff --git a/icalparse.py b/icalparse.py
index 1ed6076..653d559 100755 (executable)
--- a/icalparse.py
+++ b/icalparse.py
@@ -26,10 +26,8 @@ import os
 
 
 class InvalidICS(Exception): pass
-class notJoined(Exception): pass
 class IncompleteICS(InvalidICS): pass
 
-
 def lineJoiner(oldcal):
        '''Takes a string containing a calendar and returns an array of its lines'''
 
@@ -60,18 +58,20 @@ def lineFolder(oldcal, length=75):
                if len(line.rstrip()) <= length:
                        cal.append(line)
                else:
-                       brokenline = [line[0:length] + '\r\n']
+                       brokenline = [line[0:length]]
                        ll = length
-                       while ll < len(line.rstrip('\r\n')) + 1:
-                               brokenline.append(' ' + line[ll:sl+ll].rstrip('\r\n') + '\r\n')
+                       while ll < len(line) + 1:
+                               brokenline.append(line[ll:sl+ll])
                                ll += sl
-                       cal += brokenline
+                       brokenline = '\r\n '.join(brokenline)
+                       cal.append(brokenline)
 
        return cal
 
 
 def splitFields(cal):
-       '''Takes a list of lines in a calendar file and returns a list of key, value pairs'''
+       '''Takes a list of lines in a calendar file and returns a list of tuples        
+       as (key, value) pairs'''
 
        ical = [tuple(x.split(':',1)) for x in cal]
 
@@ -83,6 +83,13 @@ def splitFields(cal):
        return ical
 
 
+def joinFields(ical):
+       '''Takes a list of tuples that make up a calendar file and returns it to a
+       list of lines'''
+
+       return [':'.join(x) for x in ical]
+
+
 def getContent(url='',stdin=False):
        '''Generic content retriever, DO NOT use this function in a CGI script as
        it can read from the local disk (which you probably don't want it to).
@@ -118,9 +125,7 @@ def getContent(url='',stdin=False):
 
 def getHTTPContent(url='',cache='.httplib2-cache'):
        '''This function attempts to play nice when retrieving content from HTTP
-       services. It's what you should use in a CGI script. It will (by default)
-       slurp the first 20 bytes of the file and check that we are indeed looking
-       at an ICS file before going for broke.'''
+       services. It's what you should use in a CGI script.'''
 
        try:
                import httplib2
@@ -162,6 +167,63 @@ def generateRules():
        return rules
 
 
+def applyRules(ical, rules=[], verbose=False):
+       'Runs a series of rules on the lines in ical and mangles its output'
+
+       for rule in rules:
+               output = []
+               if rule.__doc__ and verbose:
+                       print(rule.__doc__)
+               for line in ical:
+                       try:
+                               out = rule(line[0],line[1])
+                       except TypeError, e:
+                               output.append(line)
+                               print(e)
+                               continue
+
+                       # Drop lines that are boolean False
+                       if not out and not out == None: continue
+
+                       # If the rule did something and is a tuple or a list we'll accept it
+                       # otherwise, pay no attention to the man behind the curtain
+                       try:
+                               if tuple(out) == out or list(out) == out and len(out) == 2:
+                                       output.append(tuple(out))
+                               else:
+                                       output.append(line)
+                       except TypeError, e:
+                               output.append(line)
+
+               ical = output
+
+       return ical
+
+
+def writeOutput(cal, outfile=''):
+       '''Takes a list of lines and outputs to the specified file'''
+
+       if not cal:
+               sys.stderr.write('Refusing to write out an empty file')
+               sys.exit(0)
+
+       if not outfile:
+               out = sys.stdout
+       else:
+               try:
+                       out = open(outfile, 'w')
+               except (IOError, OSError), e:
+                       sys.stderr.write('%s\n'%e)
+                       sys.exit(1)
+
+       if cal[-1]: cal.append('')
+
+       out.write('\r\n'.join(cal))
+
+       if not out == sys.stdout:
+               out.close()
+
+
 if __name__ == '__main__':
        from optparse import OptionParser
        # If the user passed us a 'stdin' argument, we'll go with that,
@@ -170,6 +232,8 @@ if __name__ == '__main__':
        parser = OptionParser('usage: %prog [options] url')
        parser.add_option('-s', '--stdin', action='store_true', dest='stdin',
                default=False, help='Take a calendar from standard input')
+       parser.add_option('-v', '--verbose', action='store_true', dest='verbose',
+               default=False, help='Be verbose when rules are being applied')
        parser.add_option('-o', '--output', dest='outfile', default='',
                help='Specify output file (defaults to standard output)')
 
@@ -185,6 +249,6 @@ if __name__ == '__main__':
 
        content = getContent(url, options.stdin)
        cal = lineJoiner(content)
-       ical = splitFields(cal)
-       rules = generateRules()
-       print rules
+       ical = applyRules(splitFields(cal), generateRules(), options.verbose)
+       output = lineFolder(joinFields(ical))
+       writeOutput(output, options.outfile)