#!/usr/bin/env python3

from __future__ import absolute_import

import hashlib

import os

import random

import shutil

import stat

import struct

import sys

import tempfile

import unittest

import silenttestrunner

from mercurial.node import nullid

from mercurial import (

    pycompat,

    ui as uimod,

)

# Load the local remotefilelog, not the system one

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

from hgext.remotefilelog import (

    basepack,

    historypack,

)

class histpacktests(unittest.TestCase):

    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 pycompat.fsencode(tempdir)

    def getHash(self, content):

        return hashlib.sha1(content).digest()

    def getFakeHash(self):

        return b''.join(

            pycompat.bytechr(random.randint(0, 255)) for _ in range(20)

        )

    def createPack(self, revisions=None):

        """Creates and returns a historypack containing the specified revisions.

        `revisions` is a list of tuples, where each tuple contains a filanem,

        node, p1node, p2node, and linknode.

        """

        if revisions is None:

            revisions = [

                (

                    b"filename",

                    self.getFakeHash(),

                    nullid,

                    nullid,

                    self.getFakeHash(),

                    None,

                )

            ]

        packdir = pycompat.fsencode(self.makeTempDir())

        packer = historypack.mutablehistorypack(uimod.ui(), packdir, version=2)

        for filename, node, p1, p2, linknode, copyfrom in revisions:

            packer.add(filename, node, p1, p2, linknode, copyfrom)

        path = packer.close()

        return historypack.historypack(path)

    def testAddSingle(self):

        filename = b"foo"

        node = self.getFakeHash()

        p1 = self.getFakeHash()

        p2 = self.getFakeHash()

        linknode = self.getFakeHash()

        revisions = [(filename, node, p1, p2, linknode, None)]

        pack = self.createPack(revisions)

        actual = pack.getancestors(filename, node)[node]

        self.assertEqual(p1, actual[0])

        self.assertEqual(p2, actual[1])

        self.assertEqual(linknode, actual[2])

    def testAddMultiple(self):

        """Test putting multiple unrelated revisions into a pack and reading

        them out.

        """

        revisions = []

        for i in range(10):

            filename = b"foo-%d" % i

            node = self.getFakeHash()

            p1 = self.getFakeHash()

            p2 = self.getFakeHash()

            linknode = self.getFakeHash()

            revisions.append((filename, node, p1, p2, linknode, None))

        pack = self.createPack(revisions)

        for filename, node, p1, p2, linknode, copyfrom in revisions:

            actual = pack.getancestors(filename, node)[node]

            self.assertEqual(p1, actual[0])

            self.assertEqual(p2, actual[1])

            self.assertEqual(linknode, actual[2])

            self.assertEqual(copyfrom, actual[3])

    def testAddAncestorChain(self):

        """Test putting multiple revisions in into a pack and read the ancestor

        chain.

        """

        revisions = []

        filename = b"foo"

        lastnode = nullid

        for i in range(10):

            node = self.getFakeHash()

            revisions.append((filename, node, lastnode, nullid, nullid, None))

            lastnode = node

        # revisions must be added in topological order, newest first

        revisions = list(reversed(revisions))

        pack = self.createPack(revisions)

        # Test that the chain has all the entries

        ancestors = pack.getancestors(revisions[0][0], revisions[0][1])

        for filename, node, p1, p2, linknode, copyfrom in revisions:

            ap1, ap2, alinknode, acopyfrom = ancestors[node]

            self.assertEqual(ap1, p1)

            self.assertEqual(ap2, p2)

            self.assertEqual(alinknode, linknode)

            self.assertEqual(acopyfrom, copyfrom)

    def testPackMany(self):

        # Build a random pack file

        allentries = {}

        ancestorcounts = {}

        revisions = []

        random.seed(0)

        for i in range(100):

            filename = b"filename-%d" % i

            entries = []

            p2 = nullid

            linknode = nullid

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

                node = self.getFakeHash()

                p1 = nullid

                if len(entries) > 0:

                    p1 = entries[random.randint(0, len(entries) - 1)]

                entries.append(node)

                revisions.append((filename, node, p1, p2, linknode, None))

                allentries[(filename, node)] = (p1, p2, linknode)

                if p1 == nullid:

                    ancestorcounts[(filename, node)] = 1

                else:

                    newcount = ancestorcounts[(filename, p1)] + 1

                    ancestorcounts[(filename, node)] = newcount

        # Must add file entries in reverse topological order

        revisions = list(reversed(revisions))

        pack = self.createPack(revisions)

        # Verify the pack contents

        for (filename, node) in allentries:

            ancestors = pack.getancestors(filename, node)

            self.assertEqual(ancestorcounts[(filename, node)], len(ancestors))

            for anode, (ap1, ap2, alinknode, copyfrom) in ancestors.items():

                ep1, ep2, elinknode = allentries[(filename, anode)]

                self.assertEqual(ap1, ep1)

                self.assertEqual(ap2, ep2)

                self.assertEqual(alinknode, elinknode)

                self.assertEqual(copyfrom, None)

    def testGetNodeInfo(self):

        revisions = []

        filename = b"foo"

        lastnode = nullid

        for i in range(10):

            node = self.getFakeHash()

            revisions.append((filename, node, lastnode, nullid, nullid, None))

            lastnode = node

        pack = self.createPack(revisions)

        # Test that getnodeinfo returns the expected results

        for filename, node, p1, p2, linknode, copyfrom in revisions:

            ap1, ap2, alinknode, acopyfrom = pack.getnodeinfo(filename, node)

            self.assertEqual(ap1, p1)

            self.assertEqual(ap2, p2)

            self.assertEqual(alinknode, linknode)

            self.assertEqual(acopyfrom, copyfrom)

    def testGetMissing(self):

        revisions = []

        filename = b"foo"

        for i in range(10):

            node = self.getFakeHash()

            p1 = self.getFakeHash()

            p2 = self.getFakeHash()

            linknode = self.getFakeHash()

            revisions.append((filename, node, p1, p2, linknode, None))

        pack = self.createPack(revisions)

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

        self.assertFalse(missing)

        missing = pack.getmissing(

            [(filename, revisions[0][1]), (filename, revisions[1][1])]

        )

        self.assertFalse(missing)

        fakenode = self.getFakeHash()

        missing = pack.getmissing(

            [(filename, revisions[0][1]), (filename, fakenode)]

        )

        self.assertEqual(missing, [(filename, fakenode)])

        # Test getmissing on a non-existant filename

        missing = pack.getmissing([(b"bar", fakenode)])

        self.assertEqual(missing, [(b"bar", fakenode)])

    def testAddThrows(self):

        pack = self.createPack()

        try:

            pack.add(b'filename', nullid, nullid, nullid, nullid, None)

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

        except RuntimeError:

            pass

    def testBadVersionThrows(self):

        pack = self.createPack()

        path = pack.path + b'.histpack'

        with open(path, 'rb') 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, 'wb+') as f:

            f.write(raw)

        try:

            historypack.historypack(pack.path)

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

        except RuntimeError:

            pass

    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."""

        total = basepack.SMALLFANOUTCUTOFF + 1

        revisions = []

        for i in pycompat.xrange(total):

            filename = b"foo-%d" % i

            node = self.getFakeHash()

            p1 = self.getFakeHash()

            p2 = self.getFakeHash()

            linknode = self.getFakeHash()

            revisions.append((filename, node, p1, p2, linknode, None))

        pack = self.createPack(revisions)

        self.assertEqual(pack.params.fanoutprefix, basepack.LARGEFANOUTPREFIX)

        for filename, node, p1, p2, linknode, copyfrom in revisions:

            actual = pack.getancestors(filename, node)[node]

            self.assertEqual(p1, actual[0])

            self.assertEqual(p2, actual[1])

            self.assertEqual(linknode, actual[2])

            self.assertEqual(copyfrom, actual[3])

# TODO:

# histpack store:

# - repack two packs into one

if __name__ == '__main__':

    if pycompat.iswindows:

        sys.exit(80)  # Skip on Windows

    silenttestrunner.main(__name__)