# Copyright (C) 2007, 2009, 2011 Canonical Ltd
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

from unittest import TestCase

import patiencediff

from .. import multiparent, tests

LINES_1 = b"a\nb\nc\nd\ne\n".splitlines(True)
LINES_2 = b"a\nc\nd\ne\n".splitlines(True)
LINES_3 = b"a\nb\nc\nd\n".splitlines(True)
LF_SPLIT_LINES = [b"\x00\n", b"\x00\r\x01\n", b"\x02\r\xff"]


class Mock:
    def __init__(self, **kwargs):
        self.__dict__ = kwargs


class TestMulti(TestCase):
    def test_compare_no_parent(self):
        diff = multiparent.MultiParent.from_lines(LINES_1)
        self.assertEqual([multiparent.NewText(LINES_1)], diff.hunks)

    def test_compare_one_parent(self):
        diff = multiparent.MultiParent.from_lines(LINES_1, [LINES_2])
        self.assertEqual(
            [
                multiparent.ParentText(0, 0, 0, 1),
                multiparent.NewText([b"b\n"]),
                multiparent.ParentText(0, 1, 2, 3),
            ],
            diff.hunks,
        )

        diff = multiparent.MultiParent.from_lines(LINES_2, [LINES_1])
        self.assertEqual(
            [multiparent.ParentText(0, 0, 0, 1), multiparent.ParentText(0, 2, 1, 3)],
            diff.hunks,
        )

    def test_compare_two_parents(self):
        diff = multiparent.MultiParent.from_lines(LINES_1, [LINES_2, LINES_3])
        self.assertEqual(
            [multiparent.ParentText(1, 0, 0, 4), multiparent.ParentText(0, 3, 4, 1)],
            diff.hunks,
        )

    def test_compare_two_parents_blocks(self):
        matcher = patiencediff.PatienceSequenceMatcher(None, LINES_2, LINES_1)
        blocks = matcher.get_matching_blocks()
        diff = multiparent.MultiParent.from_lines(
            LINES_1, [LINES_2, LINES_3], left_blocks=blocks
        )
        self.assertEqual(
            [multiparent.ParentText(1, 0, 0, 4), multiparent.ParentText(0, 3, 4, 1)],
            diff.hunks,
        )

    def test_get_matching_blocks(self):
        diff = multiparent.MultiParent.from_lines(LINES_1, [LINES_2])
        self.assertEqual(
            [(0, 0, 1), (1, 2, 3), (4, 5, 0)],
            list(diff.get_matching_blocks(0, len(LINES_2))),
        )

        diff = multiparent.MultiParent.from_lines(LINES_2, [LINES_1])
        self.assertEqual(
            [(0, 0, 1), (2, 1, 3), (5, 4, 0)],
            list(diff.get_matching_blocks(0, len(LINES_1))),
        )

    def test_range_iterator(self):
        diff = multiparent.MultiParent.from_lines(LINES_1, [LINES_2, LINES_3])
        diff.hunks.append(multiparent.NewText([b"q\n"]))
        self.assertEqual(
            [
                (0, 4, "parent", (1, 0, 4)),
                (4, 5, "parent", (0, 3, 4)),
                (5, 6, "new", [b"q\n"]),
            ],
            list(diff.range_iterator()),
        )

    def test_eq(self):
        diff = multiparent.MultiParent.from_lines(LINES_1)
        diff2 = multiparent.MultiParent.from_lines(LINES_1)
        self.assertEqual(diff, diff2)
        diff3 = multiparent.MultiParent.from_lines(LINES_2)
        self.assertFalse(diff == diff3)
        self.assertFalse(diff == Mock(hunks=[multiparent.NewText(LINES_1)]))
        self.assertEqual(
            multiparent.MultiParent(
                [multiparent.NewText(LINES_1), multiparent.ParentText(0, 1, 2, 3)]
            ),
            multiparent.MultiParent(
                [multiparent.NewText(LINES_1), multiparent.ParentText(0, 1, 2, 3)]
            ),
        )

    def test_to_patch(self):
        self.assertEqual(
            [b"i 1\n", b"a\n", b"\n", b"c 0 1 2 3\n"],
            list(
                multiparent.MultiParent(
                    [multiparent.NewText([b"a\n"]), multiparent.ParentText(0, 1, 2, 3)]
                ).to_patch()
            ),
        )

    def test_from_patch(self):
        self.assertEqual(
            multiparent.MultiParent(
                [multiparent.NewText([b"a\n"]), multiparent.ParentText(0, 1, 2, 3)]
            ),
            multiparent.MultiParent.from_patch(b"i 1\na\n\nc 0 1 2 3"),
        )
        self.assertEqual(
            multiparent.MultiParent(
                [multiparent.NewText([b"a"]), multiparent.ParentText(0, 1, 2, 3)]
            ),
            multiparent.MultiParent.from_patch(b"i 1\na\nc 0 1 2 3\n"),
        )

    def test_binary_content(self):
        patch = list(multiparent.MultiParent.from_lines(LF_SPLIT_LINES).to_patch())
        multiparent.MultiParent.from_patch(b"".join(patch))

    def test_make_patch_from_binary(self):
        patch = multiparent.MultiParent.from_texts(b"".join(LF_SPLIT_LINES))
        expected = multiparent.MultiParent([multiparent.NewText(LF_SPLIT_LINES)])
        self.assertEqual(expected, patch)

    def test_num_lines(self):
        mp = multiparent.MultiParent([multiparent.NewText([b"a\n"])])
        self.assertEqual(1, mp.num_lines())
        mp.hunks.append(multiparent.NewText([b"b\n", b"c\n"]))
        self.assertEqual(3, mp.num_lines())
        mp.hunks.append(multiparent.ParentText(0, 0, 3, 2))
        self.assertEqual(5, mp.num_lines())
        mp.hunks.append(multiparent.NewText([b"f\n", b"g\n"]))
        self.assertEqual(7, mp.num_lines())

    def test_to_lines(self):
        mpdiff = multiparent.MultiParent.from_texts(b"a\nb\nc\n", (b"b\nc\n",))
        lines = mpdiff.to_lines((b"b\ne\n",))
        self.assertEqual([b"a\n", b"b\n", b"e\n"], lines)


class TestNewText(TestCase):
    def test_eq(self):
        self.assertEqual(multiparent.NewText([]), multiparent.NewText([]))
        self.assertFalse(multiparent.NewText([b"a"]) == multiparent.NewText([b"b"]))
        self.assertFalse(multiparent.NewText([b"a"]) == Mock(lines=[b"a"]))

    def test_to_patch(self):
        self.assertEqual([b"i 0\n", b"\n"], list(multiparent.NewText([]).to_patch()))
        self.assertEqual(
            [b"i 1\n", b"a", b"\n"], list(multiparent.NewText([b"a"]).to_patch())
        )
        self.assertEqual(
            [b"i 1\n", b"a\n", b"\n"], list(multiparent.NewText([b"a\n"]).to_patch())
        )


class TestParentText(TestCase):
    def test_eq(self):
        self.assertEqual(
            multiparent.ParentText(1, 2, 3, 4), multiparent.ParentText(1, 2, 3, 4)
        )
        self.assertFalse(
            multiparent.ParentText(1, 2, 3, 4) == multiparent.ParentText(2, 2, 3, 4)
        )
        self.assertFalse(
            multiparent.ParentText(1, 2, 3, 4)
            == Mock(parent=1, parent_pos=2, child_pos=3, num_lines=4)
        )

    def test_to_patch(self):
        self.assertEqual(
            [b"c 0 1 2 3\n"], list(multiparent.ParentText(0, 1, 2, 3).to_patch())
        )


REV_A = [b"a\n", b"b\n", b"c\n", b"d\n"]
REV_B = [b"a\n", b"c\n", b"d\n", b"e\n"]
REV_C = [b"a\n", b"b\n", b"e\n", b"f\n"]


class TestVersionedFile(TestCase):
    def add_version(self, vf, text, version_id, parent_ids):
        vf.add_version(
            [(bytes([t]) + b"\n") for t in bytearray(text)], version_id, parent_ids
        )

    def make_vf(self):
        vf = multiparent.MultiMemoryVersionedFile()
        self.add_version(vf, b"abcd", b"rev-a", [])
        self.add_version(vf, b"acde", b"rev-b", [])
        self.add_version(vf, b"abef", b"rev-c", [b"rev-a", b"rev-b"])
        return vf

    def test_add_version(self):
        vf = self.make_vf()
        self.assertEqual(REV_A, vf._lines[b"rev-a"])
        vf.clear_cache()
        self.assertEqual(vf._lines, {})

    def test_get_line_list(self):
        vf = self.make_vf()
        vf.clear_cache()
        self.assertEqual(REV_A, vf.get_line_list([b"rev-a"])[0])
        self.assertEqual([REV_B, REV_C], vf.get_line_list([b"rev-b", b"rev-c"]))

    def test_reconstruct_empty(self):
        vf = multiparent.MultiMemoryVersionedFile()
        vf.add_version([], b"a", [])
        self.assertEqual([], self.reconstruct_version(vf, b"a"))

    @staticmethod
    def reconstruct(vf, revision_id, start, end):
        reconstructor = multiparent._Reconstructor(vf, vf._lines, vf._parents)
        lines = []
        reconstructor._reconstruct(lines, revision_id, start, end)
        return lines

    @staticmethod
    def reconstruct_version(vf, revision_id):
        reconstructor = multiparent._Reconstructor(vf, vf._lines, vf._parents)
        lines = []
        reconstructor.reconstruct_version(lines, revision_id)
        return lines

    def test_reconstructor(self):
        vf = self.make_vf()
        self.assertEqual([b"a\n", b"b\n"], self.reconstruct(vf, b"rev-a", 0, 2))
        self.assertEqual([b"c\n", b"d\n"], self.reconstruct(vf, b"rev-a", 2, 4))
        self.assertEqual([b"e\n", b"f\n"], self.reconstruct(vf, b"rev-c", 2, 4))
        self.assertEqual(
            [b"a\n", b"b\n", b"e\n", b"f\n"], self.reconstruct(vf, b"rev-c", 0, 4)
        )
        self.assertEqual(
            [b"a\n", b"b\n", b"e\n", b"f\n"], self.reconstruct_version(vf, b"rev-c")
        )

    def test_reordered(self):
        """Check for a corner case that requires re-starting the cursor"""
        vf = multiparent.MultiMemoryVersionedFile()
        # rev-b must have at least two hunks, so split a and b with c.
        self.add_version(vf, b"c", b"rev-a", [])
        self.add_version(vf, b"acb", b"rev-b", [b"rev-a"])
        # rev-c and rev-d must each have a line from a different rev-b hunk
        self.add_version(vf, b"b", b"rev-c", [b"rev-b"])
        self.add_version(vf, b"a", b"rev-d", [b"rev-b"])
        # The lines from rev-c and rev-d must appear in the opposite order
        self.add_version(vf, b"ba", b"rev-e", [b"rev-c", b"rev-d"])
        vf.clear_cache()
        lines = vf.get_line_list([b"rev-e"])[0]
        self.assertEqual([b"b\n", b"a\n"], lines)


class TestMultiVersionedFile(tests.TestCaseInTempDir):
    def test_save_load(self):
        vf = multiparent.MultiVersionedFile("foop")
        vf.add_version(b"a\nb\nc\nd".splitlines(True), b"a", [])
        vf.add_version(b"a\ne\nd\n".splitlines(True), b"b", [b"a"])
        vf.save()
        newvf = multiparent.MultiVersionedFile("foop")
        newvf.load()
        self.assertEqual(b"a\nb\nc\nd", b"".join(newvf.get_line_list([b"a"])[0]))
        self.assertEqual(b"a\ne\nd\n", b"".join(newvf.get_line_list([b"b"])[0]))

    def test_filenames(self):
        vf = multiparent.MultiVersionedFile("foop")
        vf.add_version(b"a\nb\nc\nd".splitlines(True), b"a", [])
        self.assertPathExists("foop.mpknit")
        self.assertPathDoesNotExist("foop.mpidx")
        vf.save()
        self.assertPathExists("foop.mpidx")
        vf.destroy()
        self.assertPathDoesNotExist("foop.mpknit")
        self.assertPathDoesNotExist("foop.mpidx")
