from __future__ import absolute_import, print_function

import itertools

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, str):
        return ''.join(ch + '\n' for ch in x)
    else:
        return map(insertreturns, x)

def removereturns(x):
    # the revert of "insertreturns"
    if isinstance(x, str):
        return x.replace('\n', '')
    else:
        return map(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(map(simplefctx, oldcontents))
    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 [''] + [
        ''.join([l for l, rs in linesrevs if r in rs])
        for r in sorted(revs)
    ]

# input case 0: one single commit
case0 = ['', '11']

# replace a single chunk
testfilefixup(case0, '', ['', ''])
testfilefixup(case0, '2', ['', '2'])
testfilefixup(case0, '22', ['', '22'])
testfilefixup(case0, '222', ['', '222'])

# input case 1: 3 lines, each commit adds one line
case1 = buildcontents([
    ('1', [1, 2, 3]),
    ('2', [   2, 3]),
    ('3', [      3]),
])

# 1:1 line mapping
testfilefixup(case1, '123', case1)
testfilefixup(case1, '12c', ['', '1', '12', '12c'])
testfilefixup(case1, '1b3', ['', '1', '1b', '1b3'])
testfilefixup(case1, '1bc', ['', '1', '1b', '1bc'])
testfilefixup(case1, 'a23', ['', 'a', 'a2', 'a23'])
testfilefixup(case1, 'a2c', ['', 'a', 'a2', 'a2c'])
testfilefixup(case1, 'ab3', ['', 'a', 'ab', 'ab3'])
testfilefixup(case1, 'abc', ['', 'a', 'ab', 'abc'])

# non 1:1 edits
testfilefixup(case1, 'abcd', case1)
testfilefixup(case1, 'ab', case1)

# deletion
testfilefixup(case1, '',   ['', '', '', ''])
testfilefixup(case1, '1',  ['', '1', '1', '1'])
testfilefixup(case1, '2',  ['', '', '2', '2'])
testfilefixup(case1, '3',  ['', '', '', '3'])
testfilefixup(case1, '13', ['', '1', '1', '13'])

# replaces
testfilefixup(case1, '1bb3', ['', '1', '1bb', '1bb3'])

# (confusing) replaces
testfilefixup(case1, '1bbb', case1)
testfilefixup(case1, 'bbbb', case1)
testfilefixup(case1, 'bbb3', case1)
testfilefixup(case1, '1b', case1)
testfilefixup(case1, 'bb', case1)
testfilefixup(case1, 'b3', case1)

# insertions at the beginning and the end
testfilefixup(case1, '123c', ['', '1', '12', '123c'])
testfilefixup(case1, 'a123', ['', 'a1', 'a12', 'a123'])

# (confusing) insertions
testfilefixup(case1, '1a23', case1)
testfilefixup(case1, '12b3', case1)

# input case 2: delete in the middle
case2 = buildcontents([
    ('11', [1, 2]),
    ('22', [1   ]),
    ('33', [1, 2]),
])

# deletion (optimize code should make it 2 chunks)
testfilefixup(case2, '', ['', '22', ''],
              fixups=[(4, 0, 2, 0, 0), (4, 2, 4, 0, 0)])

# 1:1 line mapping
testfilefixup(case2, 'aaaa', ['', 'aa22aa', 'aaaa'])

# non 1:1 edits
# note: unlike case0, the chunk is not "continuous" and no edit allowed
testfilefixup(case2, 'aaa', case2)

# input case 3: rev 3 reverts rev 2
case3 = buildcontents([
    ('1', [1, 2, 3]),
    ('2', [   2   ]),
    ('3', [1, 2, 3]),
])

# 1:1 line mapping
testfilefixup(case3, '13', case3)
testfilefixup(case3, '1b', ['', '1b', '12b', '1b'])
testfilefixup(case3, 'a3', ['', 'a3', 'a23', 'a3'])
testfilefixup(case3, 'ab', ['', 'ab', 'a2b', 'ab'])

# non 1:1 edits
testfilefixup(case3, 'a', case3)
testfilefixup(case3, 'abc', case3)

# deletion
testfilefixup(case3, '', ['', '', '2', ''])

# insertion
testfilefixup(case3, 'a13c', ['', 'a13c', 'a123c', 'a13c'])

# input case 4: a slightly complex case
case4 = buildcontents([
    ('1', [1, 2, 3]),
    ('2', [   2, 3]),
    ('3', [1, 2,  ]),
    ('4', [1,    3]),
    ('5', [      3]),
    ('6', [   2, 3]),
    ('7', [   2   ]),
    ('8', [   2, 3]),
    ('9', [      3]),
])

testfilefixup(case4, '1245689', case4)
testfilefixup(case4, '1a2456bbb', case4)
testfilefixup(case4, '1abc5689', case4)
testfilefixup(case4, '1ab5689', ['', '134', '1a3678', '1ab5689'])
testfilefixup(case4, 'aa2bcd8ee', ['', 'aa34', 'aa23d78', 'aa2bcd8ee'])
testfilefixup(case4, 'aa2bcdd8ee',['', 'aa34', 'aa23678', 'aa24568ee'])
testfilefixup(case4, 'aaaaaa', case4)
testfilefixup(case4, 'aa258b', ['', 'aa34', 'aa2378', 'aa258b'])
testfilefixup(case4, '25bb', ['', '34', '23678', '25689'])
testfilefixup(case4, '27', ['', '34', '23678', '245689'])
testfilefixup(case4, '28', ['', '34', '2378', '28'])
testfilefixup(case4, '', ['', '34', '37', ''])

# input case 5: replace a small chunk which is near a deleted line
case5 = buildcontents([
    ('12', [1, 2]),
    ('3',  [1]),
    ('4',  [1, 2]),
])

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

# input case 6: base "changeset" is immutable
case6 = ['1357', '0125678']

testfilefixup(case6, '0125678', case6)
testfilefixup(case6, '0a25678', case6)
testfilefixup(case6, '0a256b8', case6)
testfilefixup(case6, 'abcdefg', ['1357', 'a1c5e7g'])
testfilefixup(case6, 'abcdef', case6)
testfilefixup(case6, '', ['1357', '157'])
testfilefixup(case6, '0123456789', ['1357', '0123456789'])

# input case 7: change an empty file
case7 = ['']

testfilefixup(case7, '1', case7)