# SPDX-License-Identifier: GPL-2.0+
# Copyright (c) 2011 The Chromium OS Authors.
#

import re
import os
import subprocess
import sys

from patman import checkpatch
from patman import command
from patman import series
from patman import settings
from patman import terminal
from patman import tools

# True to use --no-decorate - we check this in Setup()
use_no_decorate = True

def LogCmd(commit_range, git_dir=None, oneline=False, reverse=False,
           count=None):
    """Create a command to perform a 'git log'

    Args:
        commit_range: Range expression to use for log, None for none
        git_dir: Path to git repository (None to use default)
        oneline: True to use --oneline, else False
        reverse: True to reverse the log (--reverse)
        count: Number of commits to list, or None for no limit
    Return:
        List containing command and arguments to run
    """
    cmd = ['git']
    if git_dir:
        cmd += ['--git-dir', git_dir]
    cmd += ['--no-pager', 'log', '--no-color']
    if oneline:
        cmd.append('--oneline')
    if use_no_decorate:
        cmd.append('--no-decorate')
    if reverse:
        cmd.append('--reverse')
    if count is not None:
        cmd.append('-n%d' % count)
    if commit_range:
        cmd.append(commit_range)

    # Add this in case we have a branch with the same name as a directory.
    # This avoids messages like this, for example:
    #   fatal: ambiguous argument 'test': both revision and filename
    cmd.append('--')
    return cmd

def CountCommitsToBranch():
    """Returns number of commits between HEAD and the tracking branch.

    This looks back to the tracking branch and works out the number of commits
    since then.

    Return:
        Number of patches that exist on top of the branch
    """
    pipe = [LogCmd('@{upstream}..', oneline=True),
            ['wc', '-l']]
    stdout = command.RunPipe(pipe, capture=True, oneline=True).stdout
    patch_count = int(stdout)
    return patch_count

def NameRevision(commit_hash):
    """Gets the revision name for a commit

    Args:
        commit_hash: Commit hash to look up

    Return:
        Name of revision, if any, else None
    """
    pipe = ['git', 'name-rev', commit_hash]
    stdout = command.RunPipe([pipe], capture=True, oneline=True).stdout

    # We expect a commit, a space, then a revision name
    name = stdout.split(' ')[1].strip()
    return name

def GuessUpstream(git_dir, branch):
    """Tries to guess the upstream for a branch

    This lists out top commits on a branch and tries to find a suitable
    upstream. It does this by looking for the first commit where
    'git name-rev' returns a plain branch name, with no ! or ^ modifiers.

    Args:
        git_dir: Git directory containing repo
        branch: Name of branch

    Returns:
        Tuple:
            Name of upstream branch (e.g. 'upstream/master') or None if none
            Warning/error message, or None if none
    """
    pipe = [LogCmd(branch, git_dir=git_dir, oneline=True, count=100)]
    result = command.RunPipe(pipe, capture=True, capture_stderr=True,
                             raise_on_error=False)
    if result.return_code:
        return None, "Branch '%s' not found" % branch
    for line in result.stdout.splitlines()[1:]:
        commit_hash = line.split(' ')[0]
        name = NameRevision(commit_hash)
        if '~' not in name and '^' not in name:
            if name.startswith('remotes/'):
                name = name[8:]
            return name, "Guessing upstream as '%s'" % name
    return None, "Cannot find a suitable upstream for branch '%s'" % branch

def GetUpstream(git_dir, branch):
    """Returns the name of the upstream for a branch

    Args:
        git_dir: Git directory containing repo
        branch: Name of branch

    Returns:
        Tuple:
            Name of upstream branch (e.g. 'upstream/master') or None if none
            Warning/error message, or None if none
    """
    try:
        remote = command.OutputOneLine('git', '--git-dir', git_dir, 'config',
                                       'branch.%s.remote' % branch)
        merge = command.OutputOneLine('git', '--git-dir', git_dir, 'config',
                                      'branch.%s.merge' % branch)
    except:
        upstream, msg = GuessUpstream(git_dir, branch)
        return upstream, msg

    if remote == '.':
        return merge, None
    elif remote and merge:
        leaf = merge.split('/')[-1]
        return '%s/%s' % (remote, leaf), None
    else:
        raise ValueError("Cannot determine upstream branch for branch "
                "'%s' remote='%s', merge='%s'" % (branch, remote, merge))


def GetRangeInBranch(git_dir, branch, include_upstream=False):
    """Returns an expression for the commits in the given branch.

    Args:
        git_dir: Directory containing git repo
        branch: Name of branch
    Return:
        Expression in the form 'upstream..branch' which can be used to
        access the commits. If the branch does not exist, returns None.
    """
    upstream, msg = GetUpstream(git_dir, branch)
    if not upstream:
        return None, msg
    rstr = '%s%s..%s' % (upstream, '~' if include_upstream else '', branch)
    return rstr, msg

def CountCommitsInRange(git_dir, range_expr):
    """Returns the number of commits in the given range.

    Args:
        git_dir: Directory containing git repo
        range_expr: Range to check
    Return:
        Number of patches that exist in the supplied range or None if none
        were found
    """
    pipe = [LogCmd(range_expr, git_dir=git_dir, oneline=True)]
    result = command.RunPipe(pipe, capture=True, capture_stderr=True,
                             raise_on_error=False)
    if result.return_code:
        return None, "Range '%s' not found or is invalid" % range_expr
    patch_count = len(result.stdout.splitlines())
    return patch_count, None

def CountCommitsInBranch(git_dir, branch, include_upstream=False):
    """Returns the number of commits in the given branch.

    Args:
        git_dir: Directory containing git repo
        branch: Name of branch
    Return:
        Number of patches that exist on top of the branch, or None if the
        branch does not exist.
    """
    range_expr, msg = GetRangeInBranch(git_dir, branch, include_upstream)
    if not range_expr:
        return None, msg
    return CountCommitsInRange(git_dir, range_expr)

def CountCommits(commit_range):
    """Returns the number of commits in the given range.

    Args:
        commit_range: Range of commits to count (e.g. 'HEAD..base')
    Return:
        Number of patches that exist on top of the branch
    """
    pipe = [LogCmd(commit_range, oneline=True),
            ['wc', '-l']]
    stdout = command.RunPipe(pipe, capture=True, oneline=True).stdout
    patch_count = int(stdout)
    return patch_count

def Checkout(commit_hash, git_dir=None, work_tree=None, force=False):
    """Checkout the selected commit for this build

    Args:
        commit_hash: Commit hash to check out
    """
    pipe = ['git']
    if git_dir:
        pipe.extend(['--git-dir', git_dir])
    if work_tree:
        pipe.extend(['--work-tree', work_tree])
    pipe.append('checkout')
    if force:
        pipe.append('-f')
    pipe.append(commit_hash)
    result = command.RunPipe([pipe], capture=True, raise_on_error=False,
                             capture_stderr=True)
    if result.return_code != 0:
        raise OSError('git checkout (%s): %s' % (pipe, result.stderr))

def Clone(git_dir, output_dir):
    """Checkout the selected commit for this build

    Args:
        commit_hash: Commit hash to check out
    """
    pipe = ['git', 'clone', git_dir, '.']
    result = command.RunPipe([pipe], capture=True, cwd=output_dir,
                             capture_stderr=True)
    if result.return_code != 0:
        raise OSError('git clone: %s' % result.stderr)

def Fetch(git_dir=None, work_tree=None):
    """Fetch from the origin repo

    Args:
        commit_hash: Commit hash to check out
    """
    pipe = ['git']
    if git_dir:
        pipe.extend(['--git-dir', git_dir])
    if work_tree:
        pipe.extend(['--work-tree', work_tree])
    pipe.append('fetch')
    result = command.RunPipe([pipe], capture=True, capture_stderr=True)
    if result.return_code != 0:
        raise OSError('git fetch: %s' % result.stderr)

def CreatePatches(start, count, ignore_binary, series):
    """Create a series of patches from the top of the current branch.

    The patch files are written to the current directory using
    git format-patch.

    Args:
        start: Commit to start from: 0=HEAD, 1=next one, etc.
        count: number of commits to include
    Return:
        Filename of cover letter
        List of filenames of patch files
    """
    if series.get('version'):
        version = '%s ' % series['version']
    cmd = ['git', 'format-patch', '-M', '--signoff']
    if ignore_binary:
        cmd.append('--no-binary')
    if series.get('cover'):
        cmd.append('--cover-letter')
    prefix = series.GetPatchPrefix()
    if prefix:
        cmd += ['--subject-prefix=%s' % prefix]
    cmd += ['HEAD~%d..HEAD~%d' % (start + count, start)]

    stdout = command.RunList(cmd)
    files = stdout.splitlines()

    # We have an extra file if there is a cover letter
    if series.get('cover'):
       return files[0], files[1:]
    else:
       return None, files

def BuildEmailList(in_list, tag=None, alias=None, raise_on_error=True):
    """Build a list of email addresses based on an input list.

    Takes a list of email addresses and aliases, and turns this into a list
    of only email address, by resolving any aliases that are present.

    If the tag is given, then each email address is prepended with this
    tag and a space. If the tag starts with a minus sign (indicating a
    command line parameter) then the email address is quoted.

    Args:
        in_list:        List of aliases/email addresses
        tag:            Text to put before each address
        alias:          Alias dictionary
        raise_on_error: True to raise an error when an alias fails to match,
                False to just print a message.

    Returns:
        List of email addresses

    >>> alias = {}
    >>> alias['fred'] = ['f.bloggs@napier.co.nz']
    >>> alias['john'] = ['j.bloggs@napier.co.nz']
    >>> alias['mary'] = ['Mary Poppins <m.poppins@cloud.net>']
    >>> alias['boys'] = ['fred', ' john']
    >>> alias['all'] = ['fred ', 'john', '   mary   ']
    >>> BuildEmailList(['john', 'mary'], None, alias)
    ['j.bloggs@napier.co.nz', 'Mary Poppins <m.poppins@cloud.net>']
    >>> BuildEmailList(['john', 'mary'], '--to', alias)
    ['--to "j.bloggs@napier.co.nz"', \
'--to "Mary Poppins <m.poppins@cloud.net>"']
    >>> BuildEmailList(['john', 'mary'], 'Cc', alias)
    ['Cc j.bloggs@napier.co.nz', 'Cc Mary Poppins <m.poppins@cloud.net>']
    """
    quote = '"' if tag and tag[0] == '-' else ''
    raw = []
    for item in in_list:
        raw += LookupEmail(item, alias, raise_on_error=raise_on_error)
    result = []
    for item in raw:
        item = tools.FromUnicode(item)
        if not item in result:
            result.append(item)
    if tag:
        return ['%s %s%s%s' % (tag, quote, email, quote) for email in result]
    return result

def EmailPatches(series, cover_fname, args, dry_run, raise_on_error, cc_fname,
        self_only=False, alias=None, in_reply_to=None, thread=False,
        smtp_server=None):
    """Email a patch series.

    Args:
        series: Series object containing destination info
        cover_fname: filename of cover letter
        args: list of filenames of patch files
        dry_run: Just return the command that would be run
        raise_on_error: True to raise an error when an alias fails to match,
                False to just print a message.
        cc_fname: Filename of Cc file for per-commit Cc
        self_only: True to just email to yourself as a test
        in_reply_to: If set we'll pass this to git as --in-reply-to.
            Should be a message ID that this is in reply to.
        thread: True to add --thread to git send-email (make
            all patches reply to cover-letter or first patch in series)
        smtp_server: SMTP server to use to send patches

    Returns:
        Git command that was/would be run

    # For the duration of this doctest pretend that we ran patman with ./patman
    >>> _old_argv0 = sys.argv[0]
    >>> sys.argv[0] = './patman'

    >>> alias = {}
    >>> alias['fred'] = ['f.bloggs@napier.co.nz']
    >>> alias['john'] = ['j.bloggs@napier.co.nz']
    >>> alias['mary'] = ['m.poppins@cloud.net']
    >>> alias['boys'] = ['fred', ' john']
    >>> alias['all'] = ['fred ', 'john', '   mary   ']
    >>> alias[os.getenv('USER')] = ['this-is-me@me.com']
    >>> series = series.Series()
    >>> series.to = ['fred']
    >>> series.cc = ['mary']
    >>> EmailPatches(series, 'cover', ['p1', 'p2'], True, True, 'cc-fname', \
            False, alias)
    'git send-email --annotate --to "f.bloggs@napier.co.nz" --cc \
"m.poppins@cloud.net" --cc-cmd "./patman --cc-cmd cc-fname" cover p1 p2'
    >>> EmailPatches(series, None, ['p1'], True, True, 'cc-fname', False, \
            alias)
    'git send-email --annotate --to "f.bloggs@napier.co.nz" --cc \
"m.poppins@cloud.net" --cc-cmd "./patman --cc-cmd cc-fname" p1'
    >>> series.cc = ['all']
    >>> EmailPatches(series, 'cover', ['p1', 'p2'], True, True, 'cc-fname', \
            True, alias)
    'git send-email --annotate --to "this-is-me@me.com" --cc-cmd "./patman \
--cc-cmd cc-fname" cover p1 p2'
    >>> EmailPatches(series, 'cover', ['p1', 'p2'], True, True, 'cc-fname', \
            False, alias)
    'git send-email --annotate --to "f.bloggs@napier.co.nz" --cc \
"f.bloggs@napier.co.nz" --cc "j.bloggs@napier.co.nz" --cc \
"m.poppins@cloud.net" --cc-cmd "./patman --cc-cmd cc-fname" cover p1 p2'

    # Restore argv[0] since we clobbered it.
    >>> sys.argv[0] = _old_argv0
    """
    to = BuildEmailList(series.get('to'), '--to', alias, raise_on_error)
    if not to:
        git_config_to = command.Output('git', 'config', 'sendemail.to',
                                       raise_on_error=False)
        if not git_config_to:
            print("No recipient.\n"
                  "Please add something like this to a commit\n"
                  "Series-to: Fred Bloggs <f.blogs@napier.co.nz>\n"
                  "Or do something like this\n"
                  "git config sendemail.to u-boot@lists.denx.de")
            return
    cc = BuildEmailList(list(set(series.get('cc')) - set(series.get('to'))),
                        '--cc', alias, raise_on_error)
    if self_only:
        to = BuildEmailList([os.getenv('USER')], '--to', alias, raise_on_error)
        cc = []
    cmd = ['git', 'send-email', '--annotate']
    if smtp_server:
        cmd.append('--smtp-server=%s' % smtp_server)
    if in_reply_to:
        cmd.append('--in-reply-to="%s"' % tools.FromUnicode(in_reply_to))
    if thread:
        cmd.append('--thread')

    cmd += to
    cmd += cc
    cmd += ['--cc-cmd', '"%s --cc-cmd %s"' % (sys.argv[0], cc_fname)]
    if cover_fname:
        cmd.append(cover_fname)
    cmd += args
    cmdstr = ' '.join(cmd)
    if not dry_run:
        os.system(cmdstr)
    return cmdstr


def LookupEmail(lookup_name, alias=None, raise_on_error=True, level=0):
    """If an email address is an alias, look it up and return the full name

    TODO: Why not just use git's own alias feature?

    Args:
        lookup_name: Alias or email address to look up
        alias: Dictionary containing aliases (None to use settings default)
        raise_on_error: True to raise an error when an alias fails to match,
                False to just print a message.

    Returns:
        tuple:
            list containing a list of email addresses

    Raises:
        OSError if a recursive alias reference was found
        ValueError if an alias was not found

    >>> alias = {}
    >>> alias['fred'] = ['f.bloggs@napier.co.nz']
    >>> alias['john'] = ['j.bloggs@napier.co.nz']
    >>> alias['mary'] = ['m.poppins@cloud.net']
    >>> alias['boys'] = ['fred', ' john', 'f.bloggs@napier.co.nz']
    >>> alias['all'] = ['fred ', 'john', '   mary   ']
    >>> alias['loop'] = ['other', 'john', '   mary   ']
    >>> alias['other'] = ['loop', 'john', '   mary   ']
    >>> LookupEmail('mary', alias)
    ['m.poppins@cloud.net']
    >>> LookupEmail('arthur.wellesley@howe.ro.uk', alias)
    ['arthur.wellesley@howe.ro.uk']
    >>> LookupEmail('boys', alias)
    ['f.bloggs@napier.co.nz', 'j.bloggs@napier.co.nz']
    >>> LookupEmail('all', alias)
    ['f.bloggs@napier.co.nz', 'j.bloggs@napier.co.nz', 'm.poppins@cloud.net']
    >>> LookupEmail('odd', alias)
    Traceback (most recent call last):
    ...
    ValueError: Alias 'odd' not found
    >>> LookupEmail('loop', alias)
    Traceback (most recent call last):
    ...
    OSError: Recursive email alias at 'other'
    >>> LookupEmail('odd', alias, raise_on_error=False)
    Alias 'odd' not found
    []
    >>> # In this case the loop part will effectively be ignored.
    >>> LookupEmail('loop', alias, raise_on_error=False)
    Recursive email alias at 'other'
    Recursive email alias at 'john'
    Recursive email alias at 'mary'
    ['j.bloggs@napier.co.nz', 'm.poppins@cloud.net']
    """
    if not alias:
        alias = settings.alias
    lookup_name = lookup_name.strip()
    if '@' in lookup_name: # Perhaps a real email address
        return [lookup_name]

    lookup_name = lookup_name.lower()
    col = terminal.Color()

    out_list = []
    if level > 10:
        msg = "Recursive email alias at '%s'" % lookup_name
        if raise_on_error:
            raise OSError(msg)
        else:
            print(col.Color(col.RED, msg))
            return out_list

    if lookup_name:
        if not lookup_name in alias:
            msg = "Alias '%s' not found" % lookup_name
            if raise_on_error:
                raise ValueError(msg)
            else:
                print(col.Color(col.RED, msg))
                return out_list
        for item in alias[lookup_name]:
            todo = LookupEmail(item, alias, raise_on_error, level + 1)
            for new_item in todo:
                if not new_item in out_list:
                    out_list.append(new_item)

    #print("No match for alias '%s'" % lookup_name)
    return out_list

def GetTopLevel():
    """Return name of top-level directory for this git repo.

    Returns:
        Full path to git top-level directory

    This test makes sure that we are running tests in the right subdir

    >>> os.path.realpath(os.path.dirname(__file__)) == \
            os.path.join(GetTopLevel(), 'tools', 'patman')
    True
    """
    return command.OutputOneLine('git', 'rev-parse', '--show-toplevel')

def GetAliasFile():
    """Gets the name of the git alias file.

    Returns:
        Filename of git alias file, or None if none
    """
    fname = command.OutputOneLine('git', 'config', 'sendemail.aliasesfile',
            raise_on_error=False)
    if fname:
        fname = os.path.join(GetTopLevel(), fname.strip())
    return fname

def GetDefaultUserName():
    """Gets the user.name from .gitconfig file.

    Returns:
        User name found in .gitconfig file, or None if none
    """
    uname = command.OutputOneLine('git', 'config', '--global', 'user.name')
    return uname

def GetDefaultUserEmail():
    """Gets the user.email from the global .gitconfig file.

    Returns:
        User's email found in .gitconfig file, or None if none
    """
    uemail = command.OutputOneLine('git', 'config', '--global', 'user.email')
    return uemail

def GetDefaultSubjectPrefix():
    """Gets the format.subjectprefix from local .git/config file.

    Returns:
        Subject prefix found in local .git/config file, or None if none
    """
    sub_prefix = command.OutputOneLine('git', 'config', 'format.subjectprefix',
                 raise_on_error=False)

    return sub_prefix

def Setup():
    """Set up git utils, by reading the alias files."""
    # Check for a git alias file also
    global use_no_decorate

    alias_fname = GetAliasFile()
    if alias_fname:
        settings.ReadGitAliases(alias_fname)
    cmd = LogCmd(None, count=0)
    use_no_decorate = (command.RunPipe([cmd], raise_on_error=False)
                       .return_code == 0)

def GetHead():
    """Get the hash of the current HEAD

    Returns:
        Hash of HEAD
    """
    return command.OutputOneLine('git', 'show', '-s', '--pretty=format:%H')

if __name__ == "__main__":
    import doctest

    doctest.testmod()