"""
author: deadc0de6 (https://github.com/deadc0de6)
Copyright (c) 2017, deadc0de6

entry point
"""

import os
import sys
import subprocess
import socket
from docopt import docopt

# local imports
from dotdrop.version import __version__ as VERSION
from dotdrop.logger import Logger
from dotdrop.templategen import Templategen
from dotdrop.installer import Installer
from dotdrop.updater import Updater
from dotdrop.comparator import Comparator
from dotdrop.dotfile import Dotfile
from dotdrop.config import Cfg
from dotdrop.utils import *

CUR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
LOG = Logger()
ENV_PROFILE = 'DOTDROP_PROFILE'
PROFILE = socket.gethostname()
if ENV_PROFILE in os.environ:
    PROFILE = os.environ[ENV_PROFILE]
TILD = '~'
TRANS_SUFFIX = 'trans'

BANNER = """     _       _      _
  __| | ___ | |_ __| |_ __ ___  _ __
 / _` |/ _ \| __/ _` | '__/ _ \| '_ |
 \__,_|\___/ \__\__,_|_|  \___/| .__/  v{}
                               |_|""".format(VERSION)

USAGE = """
{}

Usage:
  dotdrop install   [-tfndVb] [-c <path>] [-p <profile>]
  dotdrop import    [-ldVb]   [-c <path>] [-p <profile>] <paths>...
  dotdrop compare   [-Vb]     [-c <path>] [-p <profile>]
                              [-o <opts>] [-i <name>...]
                              [--files=<files>]
  dotdrop update    [-fdVb]   [-c <path>] <paths>...
  dotdrop listfiles [-Vb]     [-c <path>] [-p <profile>]
  dotdrop list      [-Vb]     [-c <path>]
  dotdrop --help
  dotdrop --version

Options:
  -p --profile=<profile>  Specify the profile to use [default: {}].
  -c --cfg=<path>         Path to the config [default: config.yaml].
  --files=<files>         Comma separated list of files to compare.
  -i --ignore=<name>      File name to ignore when diffing.
  -o --dopts=<opts>       Diff options [default: ].
  -n --nodiff             Do not diff when installing.
  -t --temp               Install to a temporary directory for review.
  -l --link               Import and link.
  -f --force              Do not warn if exists.
  -V --verbose            Be verbose.
  -d --dry                Dry run.
  -b --no-banner          Do not display the banner.
  -v --version            Show version.
  -h --help               Show this screen.

""".format(BANNER, PROFILE)

###########################################################
# entry point
###########################################################


def install(opts, conf, temporary=False):
    """install all dotfiles for this profile"""
    dotfiles = conf.get_dotfiles(opts['profile'])
    if dotfiles == []:
        msg = 'no dotfiles defined for this profile (\"{}\")'
        LOG.err(msg.format(opts['profile']))
        return False
    t = Templategen(opts['profile'], base=opts['dotpath'],
                    variables=opts['variables'], debug=opts['debug'])
    tmpdir = None
    if temporary:
        tmpdir = get_tmpdir()
    inst = Installer(create=opts['create'], backup=opts['backup'],
                     dry=opts['dry'], safe=opts['safe'], base=opts['dotpath'],
                     workdir=opts['workdir'], diff=opts['installdiff'],
                     debug=opts['debug'], totemp=tmpdir)
    installed = []
    for dotfile in dotfiles:
        if dotfile.actions and Cfg.key_actions_pre in dotfile.actions:
            for action in dotfile.actions[Cfg.key_actions_pre]:
                if opts['dry']:
                    LOG.dry('would execute action: {}'.format(action))
                else:
                    if opts['debug']:
                        LOG.dbg('executing pre action {}'.format(action))
                    action.execute()
        if opts['debug']:
            LOG.dbg('installing {}'.format(dotfile))
        if hasattr(dotfile, 'link') and dotfile.link:
            r = inst.link(t, dotfile.src, dotfile.dst)
        else:
            src = dotfile.src
            tmp = None
            if dotfile.trans:
                tmp = apply_trans(opts, dotfile)
                if not tmp:
                    continue
                src = tmp
            r = inst.install(t, src, dotfile.dst)
            if tmp:
                tmp = os.path.join(opts['dotpath'], tmp)
                if os.path.exists(tmp):
                    remove(tmp)
        if len(r) > 0:
            if Cfg.key_actions_post in dotfile.actions:
                actions = dotfile.actions[Cfg.key_actions_post]
                # execute action
                for action in actions:
                    if opts['dry']:
                        LOG.dry('would execute action: {}'.format(action))
                    else:
                        if opts['debug']:
                            LOG.dbg('executing post action {}'.format(action))
                        action.execute()
        installed.extend(r)
    if temporary:
        LOG.log('\nInstalled to tmp {}.'.format(tmpdir))
    LOG.log('\n{} dotfile(s) installed.'.format(len(installed)))
    return True


def apply_trans(opts, dotfile):
    """apply the transformation to the dotfile
    return None if fails and new source if succeed"""
    src = dotfile.src
    new_src = '{}.{}'.format(src, TRANS_SUFFIX)
    err = False
    for trans in dotfile.trans:
        if opts['debug']:
            LOG.dbg('executing transformation {}'.format(trans))
        s = os.path.join(opts['dotpath'], src)
        temp = os.path.join(opts['dotpath'], new_src)
        if not trans.transform(s, temp):
            msg = 'transformation \"{}\" failed for {}'
            LOG.err(msg.format(trans.key, dotfile.key))
            err = True
            break
    if err:
        if new_src and os.path.exists(new_src):
            remove(new_src)
        return None
    return new_src


def _select(selections, dotfiles):
    selected = []
    for selection in selections:
        df = next(
            (x for x in dotfiles
                if os.path.expanduser(x.dst) == os.path.expanduser(selection)),
            None
        )
        if df:
            selected.append(df)
        else:
            LOG.err('no dotfile matches \"{}\"'.format(selection))
    return selected


def compare(opts, conf, tmp, focus=None, ignore=[]):
    """compare dotfiles and return True if all identical"""
    dotfiles = conf.get_dotfiles(opts['profile'])
    if dotfiles == []:
        msg = 'no dotfiles defined for this profile (\"{}\")'
        LOG.err(msg.format(opts['profile']))
        return True
    # compare only specific files
    same = True
    selected = dotfiles
    if focus:
        selected = _select(focus.replace(' ', '').split(','), dotfiles)

    if len(selected) < 1:
        return False

    t = Templategen(opts['profile'], base=opts['dotpath'],
                    variables=opts['variables'], debug=opts['debug'])
    inst = Installer(create=opts['create'], backup=opts['backup'],
                     dry=opts['dry'], base=opts['dotpath'],
                     workdir=opts['workdir'], debug=opts['debug'])
    comp = Comparator(diffopts=opts['dopts'], debug=opts['debug'],
                      ignore=ignore)

    for dotfile in selected:
        if opts['debug']:
            LOG.dbg('comparing {}'.format(dotfile))
        src = dotfile.src
        if not os.path.lexists(os.path.expanduser(dotfile.dst)):
            LOG.emph('\"{}\" does not exist on local\n'.format(dotfile.dst))

        tmpsrc = None
        if dotfile.trans:
            # apply transformation
            tmpsrc = apply_trans(opts, dotfile)
            if not tmpsrc:
                # could not apply trans
                continue
            src = tmpsrc
        # install dotfile to temporary dir
        ret, insttmp = inst.install_to_temp(t, tmp, src, dotfile.dst)
        if not ret:
            # failed to install to tmp
            continue
        diff = comp.compare(insttmp, dotfile.dst)
        if tmpsrc:
            # clean tmp transformed dotfile if any
            tmpsrc = os.path.join(opts['dotpath'], tmpsrc)
            if os.path.exists(tmpsrc):
                remove(tmpsrc)
        if diff == '':
            if opts['debug']:
                LOG.dbg('diffing \"{}\" VS \"{}\"'.format(dotfile.key,
                                                          dotfile.dst))
                LOG.dbg('same file')
        else:
            LOG.log('diffing \"{}\" VS \"{}\"'.format(dotfile.key,
                                                      dotfile.dst))
            LOG.emph(diff)
            same = False

    return same


def update(opts, conf, paths):
    """update the dotfile(s) from path(s)"""
    updater = Updater(conf, opts['dotpath'], opts['dry'],
                      opts['safe'], opts['debug'])
    for path in paths:
        updater.update(path, opts['profile'])


def importer(opts, conf, paths):
    """import dotfile(s) from paths"""
    home = os.path.expanduser(TILD)
    cnt = 0
    for path in paths:
        if not os.path.lexists(path):
            LOG.err('\"{}\" does not exist, ignored !'.format(path))
            continue
        dst = path.rstrip(os.sep)
        src = dst
        if dst.startswith(home):
            src = dst[len(home):]
        strip = '.' + os.sep
        if opts['keepdot']:
            strip = os.sep
        src = src.lstrip(strip)

        # create a new dotfile
        dotfile = Dotfile('', dst, src)
        linkit = opts['link'] or opts['link_by_default']
        retconf, new_dotfile = conf.new(dotfile, opts['profile'], linkit)
        dotfile = new_dotfile

        # prepare hierarchy for dotfile
        srcf = os.path.join(CUR, opts['dotpath'], src)
        if not os.path.exists(srcf):
            cmd = ['mkdir', '-p', '{}'.format(os.path.dirname(srcf))]
            if opts['dry']:
                LOG.dry('would run: {}'.format(' '.join(cmd)))
            else:
                run(cmd, raw=False, debug=opts['debug'])
            cmd = ['cp', '-R', '-L', dst, srcf]
            if opts['dry']:
                LOG.dry('would run: {}'.format(' '.join(cmd)))
                if linkit:
                    LOG.dry('would symlink {} to {}'.format(srcf, dst))
            else:
                run(cmd, raw=False, debug=opts['debug'])
                if linkit:
                    remove(dst)
                    os.symlink(srcf, dst)
        if retconf:
            LOG.sub('\"{}\" imported'.format(path))
            cnt += 1
        else:
            LOG.warn('\"{}\" ignored'.format(path))
    if opts['dry']:
        LOG.dry('new config file would be:')
        LOG.raw(conf.dump())
    else:
        conf.save()
    LOG.log('\n{} file(s) imported.'.format(cnt))


def list_profiles(conf):
    """list all profiles"""
    LOG.log('Available profile(s):')
    for p in conf.get_profiles():
        LOG.sub(p)
    LOG.log('')


def list_files(opts, conf):
    """list all dotfiles for a specific profile"""
    if not opts['profile'] in conf.get_profiles():
        LOG.warn('unknown profile \"{}\"'.format(opts['profile']))
        return
    LOG.log('Dotfile(s) for profile \"{}\":\n'.format(opts['profile']))
    for dotfile in conf.get_dotfiles(opts['profile']):
        LOG.log('{} (file: \"{}\", link: {})'.format(dotfile.key, dotfile.src,
                                                     dotfile.link))
        LOG.sub('{}'.format(dotfile.dst))
    LOG.log('')


def header():
    """print the header"""
    LOG.log(BANNER)
    LOG.log('')


def main():
    """entry point"""
    ret = True
    args = docopt(USAGE, version=VERSION)

    try:
        conf = Cfg(os.path.expanduser(args['--cfg']))
    except ValueError as e:
        LOG.err('error: {}'.format(str(e)))
        return False

    opts = conf.get_settings()
    opts['dry'] = args['--dry']
    opts['profile'] = args['--profile']
    opts['safe'] = not args['--force']
    opts['installdiff'] = not args['--nodiff']
    opts['link'] = args['--link']
    opts['debug'] = args['--verbose']
    opts['variables'] = conf.get_variables()

    if opts['debug']:
        LOG.dbg('config file: {}'.format(args['--cfg']))
        LOG.dbg('opts: {}'.format(opts))

    if opts['banner'] and not args['--no-banner']:
        header()

    try:

        if args['list']:
            # list existing profiles
            list_profiles(conf)

        elif args['listfiles']:
            # list files for selected profile
            list_files(opts, conf)

        elif args['install']:
            # install the dotfiles stored in dotdrop
            ret = install(opts, conf, temporary=args['--temp'])

        elif args['compare']:
            # compare local dotfiles with dotfiles stored in dotdrop
            tmp = get_tmpdir()
            opts['dopts'] = args['--dopts']
            ret = compare(opts, conf, tmp, focus=args['--files'],
                          ignore=args['--ignore'])
            if os.listdir(tmp):
                LOG.raw('\ntemporary files available under {}'.format(tmp))
            else:
                os.rmdir(tmp)

        elif args['import']:
            # import dotfile(s)
            importer(opts, conf, args['<paths>'])

        elif args['update']:
            # update a dotfile
            update(opts, conf, args['<paths>'])

    except KeyboardInterrupt:
        LOG.err('interrupted')
        ret = False

    return ret


if __name__ == '__main__':
    if main():
        sys.exit(0)
    sys.exit(1)