#!/usr/bin/env python

from __future__ import absolute_import, print_function

import hashlib

import os

import random

import shutil

import stat

import struct

import sys

import tempfile

import time

import unittest

import silenttestrunner

# Load the local remotefilelog, not the system one

sys.path[0:0] = [os.path.join(os.path.dirname(__file__), '..')]

from mercurial.node import nullid

from mercurial import (

    ui as uimod,

)

from hgext.remotefilelog import (

    basepack,

    constants,

    datapack,

)

class datapacktestsbase(object):

    def __init__(self, datapackreader, paramsavailable):

        self.datapackreader = datapackreader

        self.paramsavailable = paramsavailable

    def setUp(self):

        self.tempdirs = []

    def tearDown(self):

        for d in self.tempdirs:

            shutil.rmtree(d)

    def makeTempDir(self):

        tempdir = tempfile.mkdtemp()

        self.tempdirs.append(tempdir)

        return tempdir

    def getHash(self, content):

        return hashlib.sha1(content).digest()

    def getFakeHash(self):

        return ''.join(chr(random.randint(0, 255)) for _ in range(20))

    def createPack(self, revisions=None, packdir=None, version=0):

        if revisions is None:

            revisions = [("filename", self.getFakeHash(), nullid, "content")]

        if packdir is None:

            packdir = self.makeTempDir()

        packer = datapack.mutabledatapack(

            uimod.ui(), packdir, version=version)

        for args in revisions:

            filename, node, base, content = args[0:4]

            # meta is optional

            meta = None

            if len(args) > 4:

                meta = args[4]

            packer.add(filename, node, base, content, metadata=meta)

        path = packer.close()

        return self.datapackreader(path)

    def _testAddSingle(self, content):

        """Test putting a simple blob into a pack and reading it out.

        """

        filename = "foo"

        node = self.getHash(content)

        revisions = [(filename, node, nullid, content)]

        pack = self.createPack(revisions)

        if self.paramsavailable:

            self.assertEquals(pack.params.fanoutprefix,

                              basepack.SMALLFANOUTPREFIX)

        chain = pack.getdeltachain(filename, node)

        self.assertEquals(content, chain[0][4])

    def testAddSingle(self):

        self._testAddSingle('')

    def testAddSingleEmpty(self):

        self._testAddSingle('abcdef')

    def testAddMultiple(self):

        """Test putting multiple unrelated blobs into a pack and reading them

        out.

        """

        revisions = []

        for i in range(10):

            filename = "foo%s" % i

            content = "abcdef%s" % i

            node = self.getHash(content)

            revisions.append((filename, node, self.getFakeHash(), content))

        pack = self.createPack(revisions)

        for filename, node, base, content in revisions:

            entry = pack.getdelta(filename, node)

            self.assertEquals((content, filename, base, {}), entry)

            chain = pack.getdeltachain(filename, node)

            self.assertEquals(content, chain[0][4])

    def testAddDeltas(self):

        """Test putting multiple delta blobs into a pack and read the chain.

        """

        revisions = []

        filename = "foo"

        lastnode = nullid

        for i in range(10):

            content = "abcdef%s" % i

            node = self.getHash(content)

            revisions.append((filename, node, lastnode, content))

            lastnode = node

        pack = self.createPack(revisions)

        entry = pack.getdelta(filename, revisions[0][1])

        realvalue = (revisions[0][3], filename, revisions[0][2], {})

        self.assertEquals(entry, realvalue)

        # Test that the chain for the final entry has all the others

        chain = pack.getdeltachain(filename, node)

        for i in range(10):

            content = "abcdef%s" % i

            self.assertEquals(content, chain[-i - 1][4])

    def testPackMany(self):

        """Pack many related and unrelated objects.

        """

        # Build a random pack file

        revisions = []

        blobs = {}

        random.seed(0)

        for i in range(100):

            filename = "filename-%s" % i

            filerevs = []

            for j in range(random.randint(1, 100)):

                content = "content-%s" % j

                node = self.getHash(content)

                lastnode = nullid

                if len(filerevs) > 0:

                    lastnode = filerevs[random.randint(0, len(filerevs) - 1)]

                filerevs.append(node)

                blobs[(filename, node, lastnode)] = content

                revisions.append((filename, node, lastnode, content))

        pack = self.createPack(revisions)

        # Verify the pack contents

        for (filename, node, lastnode), content in sorted(blobs.iteritems()):

            chain = pack.getdeltachain(filename, node)

            for entry in chain:

                expectedcontent = blobs[(entry[0], entry[1], entry[3])]

                self.assertEquals(entry[4], expectedcontent)

    def testPackMetadata(self):

        revisions = []

        for i in range(100):

            filename = '%s.txt' % i

            content = 'put-something-here \n' * i

            node = self.getHash(content)

            meta = {constants.METAKEYFLAG: i ** 4,

                    constants.METAKEYSIZE: len(content),

                    'Z': 'random_string',

                    '_': '\0' * i}

            revisions.append((filename, node, nullid, content, meta))

        pack = self.createPack(revisions, version=1)

        for name, node, x, content, origmeta in revisions:

            parsedmeta = pack.getmeta(name, node)

            # flag == 0 should be optimized out

            if origmeta[constants.METAKEYFLAG] == 0:

                del origmeta[constants.METAKEYFLAG]

            self.assertEquals(parsedmeta, origmeta)

    def testPackMetadataThrows(self):

        filename = '1'

        content = '2'

        node = self.getHash(content)

        meta = {constants.METAKEYFLAG: 3}

        revisions = [(filename, node, nullid, content, meta)]

        try:

            self.createPack(revisions, version=0)

            self.assertTrue(False, "should throw if metadata is not supported")

        except RuntimeError:

            pass

    def testGetMissing(self):

        """Test the getmissing() api.

        """

        revisions = []

        filename = "foo"

        lastnode = nullid

        for i in range(10):

            content = "abcdef%s" % i

            node = self.getHash(content)

            revisions.append((filename, node, lastnode, content))

            lastnode = node

        pack = self.createPack(revisions)

        missing = pack.getmissing([("foo", revisions[0][1])])

        self.assertFalse(missing)

        missing = pack.getmissing([("foo", revisions[0][1]),

                                   ("foo", revisions[1][1])])

        self.assertFalse(missing)

        fakenode = self.getFakeHash()

        missing = pack.getmissing([("foo", revisions[0][1]), ("foo", fakenode)])

        self.assertEquals(missing, [("foo", fakenode)])

    def testAddThrows(self):

        pack = self.createPack()

        try:

            pack.add('filename', nullid, 'contents')

            self.assertTrue(False, "datapack.add should throw")

        except RuntimeError:

            pass

    def testBadVersionThrows(self):

        pack = self.createPack()

        path = pack.path + '.datapack'

        with open(path) as f:

            raw = f.read()

        raw = struct.pack('!B', 255) + raw[1:]

        os.chmod(path, os.stat(path).st_mode | stat.S_IWRITE)

        with open(path, 'w+') as f:

            f.write(raw)

        try:

            pack = self.datapackreader(pack.path)

            self.assertTrue(False, "bad version number should have thrown")

        except RuntimeError:

            pass

    def testMissingDeltabase(self):

        fakenode = self.getFakeHash()

        revisions = [("filename", fakenode, self.getFakeHash(), "content")]

        pack = self.createPack(revisions)

        chain = pack.getdeltachain("filename", fakenode)

        self.assertEquals(len(chain), 1)

    def testLargePack(self):

        """Test creating and reading from a large pack with over X entries.

        This causes it to use a 2^16 fanout table instead."""

        revisions = []

        blobs = {}

        total = basepack.SMALLFANOUTCUTOFF + 1

        for i in xrange(total):

            filename = "filename-%s" % i

            content = filename

            node = self.getHash(content)

            blobs[(filename, node)] = content

            revisions.append((filename, node, nullid, content))

        pack = self.createPack(revisions)

        if self.paramsavailable:

            self.assertEquals(pack.params.fanoutprefix,

                              basepack.LARGEFANOUTPREFIX)

        for (filename, node), content in blobs.iteritems():

            actualcontent = pack.getdeltachain(filename, node)[0][4]

            self.assertEquals(actualcontent, content)

    def testPacksCache(self):

        """Test that we remember the most recent packs while fetching the delta

        chain."""

        packdir = self.makeTempDir()

        deltachains = []

        numpacks = 10

        revisionsperpack = 100

        for i in range(numpacks):

            chain = []

            revision = (str(i), self.getFakeHash(), nullid, "content")

            for _ in range(revisionsperpack):

                chain.append(revision)

                revision = (

                    str(i),

                    self.getFakeHash(),

                    revision[1],

                    self.getFakeHash()

                )

            self.createPack(chain, packdir)

            deltachains.append(chain)

        class testdatapackstore(datapack.datapackstore):

            # Ensures that we are not keeping everything in the cache.

            DEFAULTCACHESIZE = numpacks / 2

        store = testdatapackstore(uimod.ui(), packdir)

        random.shuffle(deltachains)

        for randomchain in deltachains:

            revision = random.choice(randomchain)

            chain = store.getdeltachain(revision[0], revision[1])

            mostrecentpack = next(iter(store.packs), None)

            self.assertEquals(

                mostrecentpack.getdeltachain(revision[0], revision[1]),

                chain

            )

            self.assertEquals(randomchain.index(revision) + 1, len(chain))

    # perf test off by default since it's slow

    def _testIndexPerf(self):

        random.seed(0)

        print("Multi-get perf test")

        packsizes = [

            100,

            10000,

            100000,

            500000,

            1000000,

            3000000,

        ]

        lookupsizes = [

            10,

            100,

            1000,

            10000,

            100000,

            1000000,

        ]

        for packsize in packsizes:

            revisions = []

            for i in xrange(packsize):

                filename = "filename-%s" % i

                content = "content-%s" % i

                node = self.getHash(content)

                revisions.append((filename, node, nullid, content))

            path = self.createPack(revisions).path

            # Perf of large multi-get

            import gc

            gc.disable()

            pack = self.datapackreader(path)

            for lookupsize in lookupsizes:

                if lookupsize > packsize:

                    continue

                random.shuffle(revisions)

                findnodes = [(rev[0], rev[1]) for rev in revisions]

                start = time.time()

                pack.getmissing(findnodes[:lookupsize])

                elapsed = time.time() - start

                print ("%s pack %s lookups = %0.04f" %

                       (('%s' % packsize).rjust(7),

                        ('%s' % lookupsize).rjust(7),

                        elapsed))

            print("")

            gc.enable()

        # The perf test is meant to produce output, so we always fail the test

        # so the user sees the output.

        raise RuntimeError("perf test always fails")

class datapacktests(datapacktestsbase, unittest.TestCase):

    def __init__(self, *args, **kwargs):

        datapacktestsbase.__init__(self, datapack.datapack, True)

        unittest.TestCase.__init__(self, *args, **kwargs)

# TODO:

# datapack store:

# - getmissing

# - GC two packs into one

if __name__ == '__main__':

    silenttestrunner.main(__name__)