# edrecord.py
#
# Copyright 2017 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from mercurial import (
    cmdutil,
    crecord as crecordmod,
    patch as patchmod,
    util,
)
from mercurial.i18n import _

testedwith = 'ships-with-fb-hgext'

stringio = util.stringio
originaldorecord = cmdutil.dorecord
originalrecordfilter = cmdutil.recordfilter

def uisetup(ui):
    # "editor" is otherwise not allowed as a valid option for "ui.interface"
    class edrecordui(ui.__class__):
        def interface(self, feature):
            if feature == "chunkselector":
                if (self.config("ui", "interface.%s" % feature, None) ==
                    "editor"):
                    return "editor"
                elif self.config("ui", "interface.%s" % feature, None) is None:
                    if self.config("ui", "interface", None) == "editor":
                        return "editor"
            return super(edrecordui, self).interface(feature)

    ui.__class__ = edrecordui
    cmdutil.recordfilter = recordfilter
    cmdutil.dorecord = dorecord

def dorecord(ui, repo, commitfunc, cmdsuggest, backupall,
            filterfn, *pats, **opts):
    if ui.interface("chunkselector") != "editor":
        return originaldorecord(ui, repo, commitfunc, cmdsuggest, backupall,
                                filterfn, *pats, **opts)

    overrides = {('ui', 'interactive'): True}
    with ui.configoverride(overrides, 'edrecord'):
        originaldorecord(ui, repo, commitfunc, cmdsuggest, backupall, filterfn,
                        *pats, **opts)

def recordfilter(ui, headers, operation=None):

    if ui.interface("chunkselector") != "editor":
        return originalrecordfilter(ui, headers, operation)

    # construct diff string from headers
    if len(headers) == 0:
        return [], {}

    patch = stringio()
    patch.write(crecordmod.diffhelptext)

    specials = {}

    for header in headers:
        patch.write('#\n')
        if header.special():
            # this is useful for special changes, we are able to get away with
            # only including the parts of headers that offer useful info
            specials[header.filename()] = header
            for h in header.header:
                if h.startswith('index '):
                    # starting at 'index', the headers for binary files tend to
                    # stop offering useful info for the viewer
                    patch.write(_("""\
# this modifies a binary file (all or nothing)
"""))
                    break
                if not h.startswith('diff '):
                    # For specials, we only care about the filename header.
                    # The rest can be displayed as comments
                    patch.write('# ')
                patch.write(h)
        else:
            header.write(patch)
            for hunk in header.hunks:
                hunk.write(patch)

    patcheditor = ui.config('ui', 'editor.chunkselector', None)
    if patcheditor is not None:
        override = {('ui', 'editor'): patcheditor}
    else:
        override = {}

    with ui.configoverride(override):
        patch = ui.edit(patch.getvalue(), "", extra={'suffix': '.diff'})

    # remove comments from patch
    # if there's an empty line, add a space to it
    patch = [(line if len(line) > 0 else ' ') + '\n'
             for line in patch.splitlines() if not line.startswith('#')]

    headers = patchmod.parsepatch(patch)

    applied = {}
    for h in headers:
        if h.filename() in specials:
            h = specials[h.filename()]
        applied[h.filename()] = [h] + h.hunks

    return (sum([i for i in applied.itervalues()
                 if i[0].special() or len(i) > 1], []), {})