from __future__ import absolute_import, print_function

import itertools

from mercurial import pycompat

from hgext import absorb

class simplefctx(object):

    def __init__(self, content):

        self.content = content

    def data(self):

        return self.content

def insertreturns(x):

    # insert "\n"s after each single char

    if isinstance(x, bytes):

        return b''.join(ch + b'\n' for ch in pycompat.bytestr(x))

    else:

        return pycompat.maplist(insertreturns, x)

def removereturns(x):

    # the revert of "insertreturns"

    if isinstance(x, bytes):

        return x.replace(b'\n', b'')

    else:

        return pycompat.maplist(removereturns, x)

def assertlistequal(lhs, rhs, decorator=lambda x: x):

    if lhs != rhs:

        raise RuntimeError('mismatch:\n actual:   %r\n expected: %r'

                           % tuple(map(decorator, [lhs, rhs])))

def testfilefixup(oldcontents, workingcopy, expectedcontents, fixups=None):

    """([str], str, [str], [(rev, a1, a2, b1, b2)]?) -> None

    workingcopy is a string, of which every character denotes a single line.

    oldcontents, expectedcontents are lists of strings, every character of

    every string denots a single line.

    if fixups is not None, it's the expected fixups list and will be checked.

    """

    expectedcontents = insertreturns(expectedcontents)

    oldcontents = insertreturns(oldcontents)

    workingcopy = insertreturns(workingcopy)

    state = absorb.filefixupstate(pycompat.maplist(simplefctx, oldcontents),

                                  'path')

    state.diffwith(simplefctx(workingcopy))

    if fixups is not None:

        assertlistequal(state.fixups, fixups)

    state.apply()

    assertlistequal(state.finalcontents, expectedcontents, removereturns)

def buildcontents(linesrevs):

    # linesrevs: [(linecontent : str, revs : [int])]

    revs = set(itertools.chain(*[revs for line, revs in linesrevs]))

    return [b''] + [

        b''.join([l for l, rs in linesrevs if r in rs])

        for r in sorted(revs)

    ]

# input case 0: one single commit

case0 = [b'', b'11']

# replace a single chunk

testfilefixup(case0, b'', [b'', b''])

testfilefixup(case0, b'2', [b'', b'2'])

testfilefixup(case0, b'22', [b'', b'22'])

testfilefixup(case0, b'222', [b'', b'222'])

# input case 1: 3 lines, each commit adds one line

case1 = buildcontents([

    (b'1', [1, 2, 3]),

    (b'2', [   2, 3]),

    (b'3', [      3]),

])

# 1:1 line mapping

testfilefixup(case1, b'123', case1)

testfilefixup(case1, b'12c', [b'', b'1', b'12', b'12c'])

testfilefixup(case1, b'1b3', [b'', b'1', b'1b', b'1b3'])

testfilefixup(case1, b'1bc', [b'', b'1', b'1b', b'1bc'])

testfilefixup(case1, b'a23', [b'', b'a', b'a2', b'a23'])

testfilefixup(case1, b'a2c', [b'', b'a', b'a2', b'a2c'])

testfilefixup(case1, b'ab3', [b'', b'a', b'ab', b'ab3'])

testfilefixup(case1, b'abc', [b'', b'a', b'ab', b'abc'])

# non 1:1 edits

testfilefixup(case1, b'abcd', case1)

testfilefixup(case1, b'ab', case1)

# deletion

testfilefixup(case1, b'',   [b'', b'', b'', b''])

testfilefixup(case1, b'1',  [b'', b'1', b'1', b'1'])

testfilefixup(case1, b'2',  [b'', b'', b'2', b'2'])

testfilefixup(case1, b'3',  [b'', b'', b'', b'3'])

testfilefixup(case1, b'13', [b'', b'1', b'1', b'13'])

# replaces

testfilefixup(case1, b'1bb3', [b'', b'1', b'1bb', b'1bb3'])

# (confusing) replaces

testfilefixup(case1, b'1bbb', case1)

testfilefixup(case1, b'bbbb', case1)

testfilefixup(case1, b'bbb3', case1)

testfilefixup(case1, b'1b', case1)

testfilefixup(case1, b'bb', case1)

testfilefixup(case1, b'b3', case1)

# insertions at the beginning and the end

testfilefixup(case1, b'123c', [b'', b'1', b'12', b'123c'])

testfilefixup(case1, b'a123', [b'', b'a1', b'a12', b'a123'])

# (confusing) insertions

testfilefixup(case1, b'1a23', case1)

testfilefixup(case1, b'12b3', case1)

# input case 2: delete in the middle

case2 = buildcontents([

    (b'11', [1, 2]),

    (b'22', [1   ]),

    (b'33', [1, 2]),

])

# deletion (optimize code should make it 2 chunks)

testfilefixup(case2, b'', [b'', b'22', b''],

              fixups=[(4, 0, 2, 0, 0), (4, 2, 4, 0, 0)])

# 1:1 line mapping

testfilefixup(case2, b'aaaa', [b'', b'aa22aa', b'aaaa'])

# non 1:1 edits

# note: unlike case0, the chunk is not "continuous" and no edit allowed

testfilefixup(case2, b'aaa', case2)

# input case 3: rev 3 reverts rev 2

case3 = buildcontents([

    (b'1', [1, 2, 3]),

    (b'2', [   2   ]),

    (b'3', [1, 2, 3]),

])

# 1:1 line mapping

testfilefixup(case3, b'13', case3)

testfilefixup(case3, b'1b', [b'', b'1b', b'12b', b'1b'])

testfilefixup(case3, b'a3', [b'', b'a3', b'a23', b'a3'])

testfilefixup(case3, b'ab', [b'', b'ab', b'a2b', b'ab'])

# non 1:1 edits

testfilefixup(case3, b'a', case3)

testfilefixup(case3, b'abc', case3)

# deletion

testfilefixup(case3, b'', [b'', b'', b'2', b''])

# insertion

testfilefixup(case3, b'a13c', [b'', b'a13c', b'a123c', b'a13c'])

# input case 4: a slightly complex case

case4 = buildcontents([

    (b'1', [1, 2, 3]),

    (b'2', [   2, 3]),

    (b'3', [1, 2,  ]),

    (b'4', [1,    3]),

    (b'5', [      3]),

    (b'6', [   2, 3]),

    (b'7', [   2   ]),

    (b'8', [   2, 3]),

    (b'9', [      3]),

])

testfilefixup(case4, b'1245689', case4)

testfilefixup(case4, b'1a2456bbb', case4)

testfilefixup(case4, b'1abc5689', case4)

testfilefixup(case4, b'1ab5689', [b'', b'134', b'1a3678', b'1ab5689'])

testfilefixup(case4, b'aa2bcd8ee', [b'', b'aa34', b'aa23d78', b'aa2bcd8ee'])

testfilefixup(case4, b'aa2bcdd8ee',[b'', b'aa34', b'aa23678', b'aa24568ee'])

testfilefixup(case4, b'aaaaaa', case4)

testfilefixup(case4, b'aa258b', [b'', b'aa34', b'aa2378', b'aa258b'])

testfilefixup(case4, b'25bb', [b'', b'34', b'23678', b'25689'])

testfilefixup(case4, b'27', [b'', b'34', b'23678', b'245689'])

testfilefixup(case4, b'28', [b'', b'34', b'2378', b'28'])

testfilefixup(case4, b'', [b'', b'34', b'37', b''])

# input case 5: replace a small chunk which is near a deleted line

case5 = buildcontents([

    (b'12', [1, 2]),

    (b'3',  [1]),

    (b'4',  [1, 2]),

])

testfilefixup(case5, b'1cd4', [b'', b'1cd34', b'1cd4'])

# input case 6: base "changeset" is immutable

case6 = [b'1357', b'0125678']

testfilefixup(case6, b'0125678', case6)

testfilefixup(case6, b'0a25678', case6)

testfilefixup(case6, b'0a256b8', case6)

testfilefixup(case6, b'abcdefg', [b'1357', b'a1c5e7g'])

testfilefixup(case6, b'abcdef', case6)

testfilefixup(case6, b'', [b'1357', b'157'])

testfilefixup(case6, b'0123456789', [b'1357', b'0123456789'])

# input case 7: change an empty file

case7 = [b'']

testfilefixup(case7, b'1', case7)