import datetime
import gzip
from itertools import count
import os
curdir = os.path.join(os.getcwd(), os.path.dirname(__file__))
import sys
import threading
import time
import urllib

import cherrypy
from cherrypy._cpcompat import next, ntob, quote, xrange
from cherrypy.lib import httputil

gif_bytes = ntob(
    'GIF89a\x01\x00\x01\x00\x82\x00\x01\x99"\x1e\x00\x00\x00\x00\x00'
    '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
    '\x00,\x00\x00\x00\x00\x01\x00\x01\x00\x02\x03\x02\x08\t\x00;'
)


from cherrypy.test import helper


class CacheTest(helper.CPWebCase):

    def setup_server():

        class Root:

            _cp_config = {'tools.caching.on': True}

            def __init__(self):
                self.counter = 0
                self.control_counter = 0
                self.longlock = threading.Lock()

            def index(self):
                self.counter += 1
                msg = "visit #%s" % self.counter
                return msg
            index.exposed = True

            def control(self):
                self.control_counter += 1
                return "visit #%s" % self.control_counter
            control.exposed = True

            def a_gif(self):
                cherrypy.response.headers[
                    'Last-Modified'] = httputil.HTTPDate()
                return gif_bytes
            a_gif.exposed = True

            def long_process(self, seconds='1'):
                try:
                    self.longlock.acquire()
                    time.sleep(float(seconds))
                finally:
                    self.longlock.release()
                return 'success!'
            long_process.exposed = True

            def clear_cache(self, path):
                cherrypy._cache.store[cherrypy.request.base + path].clear()
            clear_cache.exposed = True

        class VaryHeaderCachingServer(object):

            _cp_config = {
                'tools.caching.on': True,
                'tools.response_headers.on': True,
                'tools.response_headers.headers': [
                    ('Vary', 'Our-Varying-Header')
                ],
            }

            def __init__(self):
                self.counter = count(1)

            def index(self):
                return "visit #%s" % next(self.counter)
            index.exposed = True

        class UnCached(object):
            _cp_config = {'tools.expires.on': True,
                          'tools.expires.secs': 60,
                          'tools.staticdir.on': True,
                          'tools.staticdir.dir': 'static',
                          'tools.staticdir.root': curdir,
                          }

            def force(self):
                cherrypy.response.headers['Etag'] = 'bibbitybobbityboo'
                self._cp_config['tools.expires.force'] = True
                self._cp_config['tools.expires.secs'] = 0
                return "being forceful"
            force.exposed = True
            force._cp_config = {'tools.expires.secs': 0}

            def dynamic(self):
                cherrypy.response.headers['Etag'] = 'bibbitybobbityboo'
                cherrypy.response.headers['Cache-Control'] = 'private'
                return "D-d-d-dynamic!"
            dynamic.exposed = True

            def cacheable(self):
                cherrypy.response.headers['Etag'] = 'bibbitybobbityboo'
                return "Hi, I'm cacheable."
            cacheable.exposed = True

            def specific(self):
                cherrypy.response.headers[
                    'Etag'] = 'need_this_to_make_me_cacheable'
                return "I am being specific"
            specific.exposed = True
            specific._cp_config = {'tools.expires.secs': 86400}

            class Foo(object):
                pass

            def wrongtype(self):
                cherrypy.response.headers[
                    'Etag'] = 'need_this_to_make_me_cacheable'
                return "Woops"
            wrongtype.exposed = True
            wrongtype._cp_config = {'tools.expires.secs': Foo()}

        cherrypy.tree.mount(Root())
        cherrypy.tree.mount(UnCached(), "/expires")
        cherrypy.tree.mount(VaryHeaderCachingServer(), "/varying_headers")
        cherrypy.config.update({'tools.gzip.on': True})
    setup_server = staticmethod(setup_server)

    def testCaching(self):
        elapsed = 0.0
        for trial in range(10):
            self.getPage("/")
            # The response should be the same every time,
            # except for the Age response header.
            self.assertBody('visit #1')
            if trial != 0:
                age = int(self.assertHeader("Age"))
                self.assert_(age >= elapsed)
                elapsed = age

        # POST, PUT, DELETE should not be cached.
        self.getPage("/", method="POST")
        self.assertBody('visit #2')
        # Because gzip is turned on, the Vary header should always Vary for
        # content-encoding
        self.assertHeader('Vary', 'Accept-Encoding')
        # The previous request should have invalidated the cache,
        # so this request will recalc the response.
        self.getPage("/", method="GET")
        self.assertBody('visit #3')
        # ...but this request should get the cached copy.
        self.getPage("/", method="GET")
        self.assertBody('visit #3')
        self.getPage("/", method="DELETE")
        self.assertBody('visit #4')

        # The previous request should have invalidated the cache,
        # so this request will recalc the response.
        self.getPage("/", method="GET", headers=[('Accept-Encoding', 'gzip')])
        self.assertHeader('Content-Encoding', 'gzip')
        self.assertHeader('Vary')
        self.assertEqual(
            cherrypy.lib.encoding.decompress(self.body), ntob("visit #5"))

        # Now check that a second request gets the gzip header and gzipped body
        # This also tests a bug in 3.0 to 3.0.2 whereby the cached, gzipped
        # response body was being gzipped a second time.
        self.getPage("/", method="GET", headers=[('Accept-Encoding', 'gzip')])
        self.assertHeader('Content-Encoding', 'gzip')
        self.assertEqual(
            cherrypy.lib.encoding.decompress(self.body), ntob("visit #5"))

        # Now check that a third request that doesn't accept gzip
        # skips the cache (because the 'Vary' header denies it).
        self.getPage("/", method="GET")
        self.assertNoHeader('Content-Encoding')
        self.assertBody('visit #6')

    def testVaryHeader(self):
        self.getPage("/varying_headers/")
        self.assertStatus("200 OK")
        self.assertHeaderItemValue('Vary', 'Our-Varying-Header')
        self.assertBody('visit #1')

        # Now check that different 'Vary'-fields don't evict each other.
        # This test creates 2 requests with different 'Our-Varying-Header'
        # and then tests if the first one still exists.
        self.getPage("/varying_headers/",
                     headers=[('Our-Varying-Header', 'request 2')])
        self.assertStatus("200 OK")
        self.assertBody('visit #2')

        self.getPage("/varying_headers/",
                     headers=[('Our-Varying-Header', 'request 2')])
        self.assertStatus("200 OK")
        self.assertBody('visit #2')

        self.getPage("/varying_headers/")
        self.assertStatus("200 OK")
        self.assertBody('visit #1')

    def testExpiresTool(self):
        # test setting an expires header
        self.getPage("/expires/specific")
        self.assertStatus("200 OK")
        self.assertHeader("Expires")

        # test exceptions for bad time values
        self.getPage("/expires/wrongtype")
        self.assertStatus(500)
        self.assertInBody("TypeError")

        # static content should not have "cache prevention" headers
        self.getPage("/expires/index.html")
        self.assertStatus("200 OK")
        self.assertNoHeader("Pragma")
        self.assertNoHeader("Cache-Control")
        self.assertHeader("Expires")

        # dynamic content that sets indicators should not have
        # "cache prevention" headers
        self.getPage("/expires/cacheable")
        self.assertStatus("200 OK")
        self.assertNoHeader("Pragma")
        self.assertNoHeader("Cache-Control")
        self.assertHeader("Expires")

        self.getPage('/expires/dynamic')
        self.assertBody("D-d-d-dynamic!")
        # the Cache-Control header should be untouched
        self.assertHeader("Cache-Control", "private")
        self.assertHeader("Expires")

        # configure the tool to ignore indicators and replace existing headers
        self.getPage("/expires/force")
        self.assertStatus("200 OK")
        # This also gives us a chance to test 0 expiry with no other headers
        self.assertHeader("Pragma", "no-cache")
        if cherrypy.server.protocol_version == "HTTP/1.1":
            self.assertHeader("Cache-Control", "no-cache, must-revalidate")
        self.assertHeader("Expires", "Sun, 28 Jan 2007 00:00:00 GMT")

        # static content should now have "cache prevention" headers
        self.getPage("/expires/index.html")
        self.assertStatus("200 OK")
        self.assertHeader("Pragma", "no-cache")
        if cherrypy.server.protocol_version == "HTTP/1.1":
            self.assertHeader("Cache-Control", "no-cache, must-revalidate")
        self.assertHeader("Expires", "Sun, 28 Jan 2007 00:00:00 GMT")

        # the cacheable handler should now have "cache prevention" headers
        self.getPage("/expires/cacheable")
        self.assertStatus("200 OK")
        self.assertHeader("Pragma", "no-cache")
        if cherrypy.server.protocol_version == "HTTP/1.1":
            self.assertHeader("Cache-Control", "no-cache, must-revalidate")
        self.assertHeader("Expires", "Sun, 28 Jan 2007 00:00:00 GMT")

        self.getPage('/expires/dynamic')
        self.assertBody("D-d-d-dynamic!")
        # dynamic sets Cache-Control to private but it should  be
        # overwritten here ...
        self.assertHeader("Pragma", "no-cache")
        if cherrypy.server.protocol_version == "HTTP/1.1":
            self.assertHeader("Cache-Control", "no-cache, must-revalidate")
        self.assertHeader("Expires", "Sun, 28 Jan 2007 00:00:00 GMT")

    def testLastModified(self):
        self.getPage("/a.gif")
        self.assertStatus(200)
        self.assertBody(gif_bytes)
        lm1 = self.assertHeader("Last-Modified")

        # this request should get the cached copy.
        self.getPage("/a.gif")
        self.assertStatus(200)
        self.assertBody(gif_bytes)
        self.assertHeader("Age")
        lm2 = self.assertHeader("Last-Modified")
        self.assertEqual(lm1, lm2)

        # this request should match the cached copy, but raise 304.
        self.getPage("/a.gif", [('If-Modified-Since', lm1)])
        self.assertStatus(304)
        self.assertNoHeader("Last-Modified")
        if not getattr(cherrypy.server, "using_apache", False):
            self.assertHeader("Age")

    def test_antistampede(self):
        SECONDS = 4
        # We MUST make an initial synchronous request in order to create the
        # AntiStampedeCache object, and populate its selecting_headers,
        # before the actual stampede.
        self.getPage("/long_process?seconds=%d" % SECONDS)
        self.assertBody('success!')
        self.getPage("/clear_cache?path=" +
                     quote('/long_process?seconds=%d' % SECONDS, safe=''))
        self.assertStatus(200)

        start = datetime.datetime.now()

        def run():
            self.getPage("/long_process?seconds=%d" % SECONDS)
            # The response should be the same every time
            self.assertBody('success!')
        ts = [threading.Thread(target=run) for i in xrange(100)]
        for t in ts:
            t.start()
        for t in ts:
            t.join()
        self.assertEqualDates(start, datetime.datetime.now(),
                              # Allow a second (two, for slow hosts)
                              # for our thread/TCP overhead etc.
                              seconds=SECONDS + 2)

    def test_cache_control(self):
        self.getPage("/control")
        self.assertBody('visit #1')
        self.getPage("/control")
        self.assertBody('visit #1')

        self.getPage("/control", headers=[('Cache-Control', 'no-cache')])
        self.assertBody('visit #2')
        self.getPage("/control")
        self.assertBody('visit #2')

        self.getPage("/control", headers=[('Pragma', 'no-cache')])
        self.assertBody('visit #3')
        self.getPage("/control")
        self.assertBody('visit #3')

        time.sleep(1)
        self.getPage("/control", headers=[('Cache-Control', 'max-age=0')])
        self.assertBody('visit #4')
        self.getPage("/control")
        self.assertBody('visit #4')
