#!/usr/bin/env python

import sys
import os
import re
import urllib2
import time
from xml.dom.minidom import Document

try:
    import xml.etree.ElementTree as ElementTree 
except ImportError:
    try:
        import cElementTree as ElementTree
    except ImportError:
        try:
            import elementtree.ElementTree as ElementTree
        except ImportError:
            import lxml.etree as ElementTree

missing_deps = False
try:
    import simplejson
    from BeautifulSoup import BeautifulSoup
except ImportError, E:
    missing_deps = E 

feedName = "example-list.xml"
feedPath = "http://openlayers.org/dev/examples/"

def getListOfOnlineExamples(baseUrl):
    """
    useful if you want to get a list of examples a url. not used by default.
    """
    html = urllib2.urlopen(baseUrl)
    soup = BeautifulSoup(html)
    examples = soup.findAll('li')
    examples = [example.find('a').get('href') for example in examples]
    examples = [example for example in examples if example.endswith('.html')]
    examples = [example for example in examples]
    return examples
    
def getListOfExamples(relPath):
    """
    returns list of .html filenames within a given path - excludes example-list.html
    """
    examples = os.listdir(relPath)
    examples = [example for example in examples if example.endswith('.html') and example != "example-list.html"]
    return examples
    

def getExampleHtml(location):
    """
    returns html of a specific example that is available online or locally
    """
    print '.',
    if location.startswith('http'):
        return urllib2.urlopen(location).read()
    else:
        f = open(location)
        html = f.read()
        f.close()
        return html
        
    
def extractById(soup, tagId, value=None):
    """
    returns full contents of a particular tag id
    """
    beautifulTag = soup.find(id=tagId)
    if beautifulTag:
        if beautifulTag.contents: 
            value = str(beautifulTag.renderContents()).strip()
            value = value.replace('\t','')
            value = value.replace('\n','')
    return value

def getRelatedClasses(html):
    """
    parses the html, and returns a list of all OpenLayers Classes 
    used within (ie what parts of OL the javascript uses).  
    """
    rawstr = r'''(?P<class>OpenLayers\..*?)\('''
    return re.findall(rawstr, html)

def parseHtml(html,ids):
    """
    returns dictionary of items of interest
    """
    soup = BeautifulSoup(html)
    d = {}
    for tagId in ids:
        d[tagId] = extractById(soup,tagId)
    #classes should eventually be parsed from docs - not automatically created.
    classes = getRelatedClasses(html)
    d['classes'] = classes
    return d

def getSvnInfo(path):
    h = os.popen("svn info %s --xml" % path)
    tree = ElementTree.fromstring(h.read())
    h.close()
    d = {
        'url': tree.findtext('entry/url'),
        'author': tree.findtext('entry/commit/author'),
        'date': tree.findtext('entry/commit/date')
    }
    return d
    
def createFeed(examples):
    doc = Document()
    atomuri = "http://www.w3.org/2005/Atom"
    feed = doc.createElementNS(atomuri, "feed")
    feed.setAttribute("xmlns", atomuri)
    title = doc.createElementNS(atomuri, "title")
    title.appendChild(doc.createTextNode("OpenLayers Examples"))
    feed.appendChild(title)
    link = doc.createElementNS(atomuri, "link")
    link.setAttribute("rel", "self")
    link.setAttribute("href", feedPath + feedName)
    
    modtime = time.strftime("%Y-%m-%dT%I:%M:%SZ", time.gmtime())
    id = doc.createElementNS(atomuri, "id")
    id.appendChild(doc.createTextNode("%s%s#%s" % (feedPath, feedName, modtime)))
    feed.appendChild(id)
    
    updated = doc.createElementNS(atomuri, "updated")
    updated.appendChild(doc.createTextNode(modtime))
    feed.appendChild(updated)

    examples.sort(key=lambda x:x["modified"])
    for example in sorted(examples, key=lambda x:x["modified"], reverse=True):
        entry = doc.createElementNS(atomuri, "entry")
        
        title = doc.createElementNS(atomuri, "title")
        title.appendChild(doc.createTextNode(example["title"] or example["example"]))
        entry.appendChild(title)
        
        link = doc.createElementNS(atomuri, "link")
        link.setAttribute("href", "%s%s" % (feedPath, example["example"]))
        entry.appendChild(link)
    
        summary = doc.createElementNS(atomuri, "summary")
        summary.appendChild(doc.createTextNode(example["shortdesc"] or example["example"]))
        entry.appendChild(summary)
        
        updated = doc.createElementNS(atomuri, "updated")
        updated.appendChild(doc.createTextNode(example["modified"]))
        entry.appendChild(updated)
        
        author = doc.createElementNS(atomuri, "author")
        name = doc.createElementNS(atomuri, "name")
        name.appendChild(doc.createTextNode(example["author"]))
        author.appendChild(name)
        entry.appendChild(author)
        
        id = doc.createElementNS(atomuri, "id")
        id.appendChild(doc.createTextNode("%s%s#%s" % (feedPath, example["example"], example["modified"])))
        entry.appendChild(id)
        
        feed.appendChild(entry)

    doc.appendChild(feed)
    return doc    
    
def wordIndex(examples):
    """
    Create an inverted index based on words in title and shortdesc.  Keys are
    lower cased words.  Values are dictionaries with example index keys and
    count values.
    """
    index = {}
    unword = re.compile("\\W+")
    keys = ["shortdesc", "title"]
    for i in range(len(examples)):
        for key in keys:
            text = examples[i][key]
            if text:
                words = unword.split(text)
                for word in words:
                    if word:
                        word = word.lower()
                        if index.has_key(word):
                            if index[word].has_key(i):
                                index[word][i] += 1
                            else:
                                index[word][i] = 1
                        else:
                            index[word] = {i: 1}
    return index
    
if __name__ == "__main__":

    if missing_deps:
        print "This script requires simplejson and BeautifulSoup. You don't have them. \n(%s)" % E
        sys.exit()
    
    if len(sys.argv) > 1:
        outFile = open(sys.argv[1],'w')
    else:
        outFile = open('../examples/example-list.js','w')
    
    examplesLocation = '../examples'
    print 'Reading examples from %s and writing out to %s' % (examplesLocation, outFile.name)
   
    exampleList = []
    docIds = ['title','shortdesc']
   
    #comment out option to create docs from online resource
    #examplesLocation = 'http://svn.openlayers.org/sandbox/docs/examples/'
    #examples = getListOfOnlineExamples(examplesLocation)

    examples = getListOfExamples(examplesLocation)

    modtime = time.strftime("%Y-%m-%dT%I:%M:%SZ", time.gmtime())

    for example in examples:
        url = os.path.join(examplesLocation,example)
        html = getExampleHtml(url)
        tagvalues = parseHtml(html,docIds)
        tagvalues['example'] = example
        # add in svn info
        d = getSvnInfo(url)
        tagvalues["modified"] = d["date"] or modtime
        tagvalues["author"] = d["author"] or "anonymous"
        tagvalues['link'] = example

        exampleList.append(tagvalues)
        
    print
    
    exampleList.sort(key=lambda x:x['example'].lower())
    
    index = wordIndex(exampleList)

    json = simplejson.dumps({"examples": exampleList, "index": index})
    #give the json a global variable we can use in our js.  This should be replaced or made optional.
    json = 'var info=' + json 
    outFile.write(json)
    outFile.close()

    print "writing feed to ../examples/%s " % feedName
    atom = open('../examples/%s' % feedName, 'w')
    doc = createFeed(exampleList)
    atom.write(doc.toxml())
    atom.close()


    print 'complete'