import os
import re
from threading import Thread
from typing import List, Set, Tuple, Dict, Iterable

from bauh.commons import system
from bauh.commons.system import run_cmd, new_subprocess, new_root_subprocess, SystemProcess, SimpleProcess
from bauh.commons.util import size_to_byte
from bauh.gems.arch.exceptions import PackageNotFoundException

RE_DEPS = re.compile(r'[\w\-_]+:[\s\w_\-\.]+\s+\[\w+\]')
RE_OPTDEPS = re.compile(r'[\w\._\-]+\s*:')
RE_DEP_NOTFOUND = re.compile(r'error:.+\'(.+)\'')
RE_DEP_OPERATORS = re.compile(r'[<>=]')
RE_INSTALLED_FIELDS = re.compile(r'(Name|Description|Version|Validated By)\s*:\s*(.+)')
RE_INSTALLED_SIZE = re.compile(r'Installed Size\s*:\s*([0-9,\.]+)\s(\w+)\n?', re.IGNORECASE)
RE_DOWNLOAD_SIZE = re.compile(r'Download Size\s*:\s*([0-9,\.]+)\s(\w+)\n?', re.IGNORECASE)
RE_UPDATE_REQUIRED_FIELDS = re.compile(r'(\bProvides\b|\bInstalled Size\b|\bConflicts With\b)\s*:\s(.+)\n')
RE_REMOVE_TRANSITIVE_DEPS = re.compile(r'removing\s([\w\-_]+)\s.+required\sby\s([\w\-_]+)\n?')
RE_AVAILABLE_MIRRORS = re.compile(r'.+\s+OK\s+.+\s+(\d+:\d+)\s+.+(http.+)')
RE_PACMAN_SYNC_FIRST = re.compile(r'SyncFirst\s*=\s*(.+)')


def is_available() -> bool:
    res = run_cmd('which pacman', print_error=False)
    return res and not res.strip().startswith('which ')


def get_repositories(pkgs: Iterable[str]) -> dict:
    pkgre = '|'.join(pkgs).replace('+', r'\+').replace('.', r'\.')

    searchres = new_subprocess(['pacman', '-Ss', pkgre]).stdout
    repositories = {}

    for line in new_subprocess(['grep', '-E', '.+/({}) '.format(pkgre)], stdin=searchres).stdout:
        if line:
            match = line.decode()
            for p in pkgs:
                if p in match:
                    repositories[p] = match.split('/')[0]

    not_found = {pkg for pkg in pkgs if pkg and pkg not in repositories}

    if not_found:  # if there are some packages not found, try to find via the single method:
        for dep in not_found:
            repo_data = guess_repository(dep)

            if repo_data:
                repositories[repo_data[0]] = repo_data[1]

    return repositories


def is_available_in_repositories(pkg_name: str) -> bool:
    return bool(run_cmd('pacman -Ss ' + pkg_name))


def get_info(pkg_name, remote: bool = False) -> str:
    return run_cmd('pacman -{}i {}'.format('Q' if not remote else 'S', pkg_name), print_error=False)


def get_info_list(pkg_name: str, remote: bool = False) -> List[tuple]:
    info = get_info(pkg_name, remote)
    if info:
        return re.findall(r'(\w+\s?\w+)\s*:\s*(.+(\n\s+.+)*)', info)


def get_info_dict(pkg_name: str, remote: bool = False) -> dict:
    list_attrs = {'depends on', 'required by'}
    info_list = get_info_list(pkg_name, remote)

    if info_list:
        info_dict = {}
        for info_data in info_list:
            attr = info_data[0].lower().strip()
            info_dict[attr] = info_data[1]

            if info_dict[attr] == 'None':
                info_dict[attr] = None

            if attr == 'optional deps' and info_dict[attr]:
                info_dict[attr] = info_dict[attr].split('\n')
            elif attr in list_attrs and info_dict[attr]:
                info_dict[attr] = [d.strip() for d in info_dict[attr].split(' ') if d]

        return info_dict


def check_installed(pkg: str) -> bool:
    res = run_cmd('pacman -Qq ' + pkg, print_error=False)
    return bool(res)


def _fill_ignored(res: dict):
    res['pkgs'] = list_ignored_packages()


def map_installed(names: Iterable[str] = None) -> dict:  # returns a dict with with package names as keys and versions as values
    ignored = {}
    thread_ignored = Thread(target=_fill_ignored, args=(ignored,), daemon=True)
    thread_ignored.start()

    allinfo = run_cmd('pacman -Qi{}'.format(' ' + ' '.join(names) if names else ''), print_error=False)

    pkgs = {'signed': {}, 'not_signed': {}}
    current_pkg = {}

    if allinfo:
        for idx, field_tuple in enumerate(RE_INSTALLED_FIELDS.findall(allinfo)):
            if field_tuple[0].startswith('N'):
                current_pkg['name'] = field_tuple[1].strip()
            elif field_tuple[0].startswith('Ve'):
                current_pkg['version'] = field_tuple[1].split(':')[-1].strip()
            elif field_tuple[0].startswith('D'):
                current_pkg['description'] = field_tuple[1].strip()
            elif field_tuple[0].startswith('Va'):
                if field_tuple[1].strip().lower() == 'none':
                    pkgs['not_signed'][current_pkg['name']] = current_pkg
                    del current_pkg['name']
                else:
                    pkgs['signed'][current_pkg['name']] = current_pkg
                    del current_pkg['name']

                current_pkg = {}

    if pkgs['signed'] or pkgs['not_signed']:
        thread_ignored.join()

        if ignored['pkgs']:
            to_del = set()

            for key in ('signed', 'not_signed'):
                if pkgs.get(key):
                    for pkg in pkgs[key].keys():
                        if pkg in ignored['pkgs']:
                            to_del.add(pkg)

                for pkg in to_del:
                    del pkgs[key][pkg]
    return pkgs


def install_as_process(pkgpaths: Iterable[str], root_password: str, file: bool, pkgdir: str = '.') -> SimpleProcess:
    if file:
        cmd = ['pacman', '-U', *pkgpaths, '--noconfirm']  # pkgpath = install file path
    else:
        cmd = ['pacman', '-S', *pkgpaths, '--noconfirm']  # pkgpath = pkgname

    return SimpleProcess(cmd=cmd,
                         root_password=root_password,
                         cwd=pkgdir,
                         error_phrases={"error: failed to prepare transaction", 'error: failed to commit transaction', 'error: target not found'},
                         shell=True)


def list_desktop_entries(pkgnames: Set[str]) -> List[str]:
    if pkgnames:
        installed_files = new_subprocess(['pacman', '-Qlq', *pkgnames])

        desktop_files = []
        for out in new_subprocess(['grep', '-E', ".desktop$"], stdin=installed_files.stdout).stdout:
            if out:
                desktop_files.append(out.decode().strip())

        return desktop_files


def list_icon_paths(pkgnames: Set[str]) -> List[str]:
    installed_files = new_subprocess(['pacman', '-Qlq', *pkgnames])

    icon_files = []
    for out in new_subprocess(['grep', '-E', '.(png|svg|xpm)$'], stdin=installed_files.stdout).stdout:
        if out:
            line = out.decode().strip()
            if line:
                icon_files.append(line)

    return icon_files


def list_bin_paths(pkgnames: Set[str]) -> List[str]:
    installed_files = new_subprocess(['pacman', '-Qlq', *pkgnames])

    bin_paths = []
    for out in new_subprocess(['grep', '-E', '^/usr/bin/.+'], stdin=installed_files.stdout).stdout:
        if out:
            line = out.decode().strip()
            if line:
                bin_paths.append(line)

    return bin_paths


def list_installed_files(pkgname: str) -> List[str]:
    installed_files = new_subprocess(['pacman', '-Qlq', pkgname])

    f_paths = []

    for out in new_subprocess(['grep', '-E', '/.+\..+[^/]$'], stdin=installed_files.stdout).stdout:
        if out:
            line = out.decode().strip()
            if line:
                f_paths.append(line)

    return f_paths


def verify_pgp_key(key: str) -> bool:
    list_key = new_subprocess(['pacman-key', '-l']).stdout

    for out in new_subprocess(['grep', " " + key], stdin=list_key).stdout:
        if out:
            line = out.decode().strip()
            if line and key in line:
                return True

    return False


def receive_key(key: str, root_password: str) -> SystemProcess:
    return SystemProcess(new_root_subprocess(['pacman-key', '-r', key], root_password=root_password), check_error_output=False)


def sign_key(key: str, root_password: str) -> SystemProcess:
    return SystemProcess(new_root_subprocess(['pacman-key', '--lsign-key', key], root_password=root_password), check_error_output=False)


def list_ignored_packages(config_path: str = '/etc/pacman.conf') -> Set[str]:
    pacman_conf = new_subprocess(['cat', config_path])

    ignored = set()
    grep = new_subprocess(['grep', '-Eo', r'\s*#*\s*ignorepkg\s*=\s*.+'], stdin=pacman_conf.stdout)
    for o in grep.stdout:
        if o:
            line = o.decode().strip()

            if not line.startswith('#'):
                ignored.add(line.split('=')[1].strip())

    pacman_conf.terminate()
    grep.terminate()
    return ignored


def check_missing(names: Set[str]) -> Set[str]:
    installed = new_subprocess(['pacman', '-Qq', *names])

    not_installed = set()

    for o in installed.stderr:
        if o:
            err_line = o.decode()

            if err_line:
                not_found = [n for n in RE_DEP_NOTFOUND.findall(err_line) if n]

                if not_found:
                    not_installed.update(not_found)

    return not_installed


def read_repository_from_info(name: str) -> str:
    info = new_subprocess(['pacman', '-Si', name])

    not_found = False
    for o in info.stderr:
        if o:
            err_line = o.decode()
            if RE_DEP_NOTFOUND.findall(err_line):
                not_found = True

    if not_found:
        return

    repository = None

    for o in new_subprocess(['grep', '-Po', "Repository\s+:\s+\K.+"], stdin=info.stdout).stdout:
        if o:
            line = o.decode().strip()

            if line:
                repository = line

    return repository


def guess_repository(name: str) -> Tuple[str, str]:
    if not name:
        raise Exception("'name' cannot be None or blank")

    only_name = RE_DEP_OPERATORS.split(name)[0]
    res = run_cmd('pacman -Ss {}'.format(only_name))

    if res:
        lines = res.split('\n')

        if lines:
            for line in lines:
                if line and not line.startswith(' '):
                    data = line.split('/')
                    line_name, line_repo = data[1].split(' ')[0], data[0]

                    provided = read_provides(line_name)

                    if provided:
                        found = {p for p in provided if only_name == RE_DEP_OPERATORS.split(p)[0]}

                        if found:
                            return line_name, line_repo


def read_provides(name: str) -> Set[str]:
    dep_info = new_subprocess(['pacman', '-Si', name])

    not_found = False

    for o in dep_info.stderr:
        if o:
            err_line = o.decode()

            if err_line:
                if RE_DEP_NOTFOUND.findall(err_line):
                    not_found = True

    if not_found:
        raise PackageNotFoundException(name)

    provides = None

    for out in new_subprocess(['grep', '-Po', 'Provides\s+:\s\K(.+)'], stdin=dep_info.stdout).stdout:
        if out:
            provided_names = [p.strip() for p in out.decode().strip().split(' ') if p]

            if provided_names[0].lower() == 'none':
                provides = {name}
            else:
                provides = {name, *provided_names}

    return provides


def read_dependencies(name: str) -> Set[str]:
    dep_info = new_subprocess(['pacman', '-Si', name])

    not_found = False

    for o in dep_info.stderr:
        if o:
            err_line = o.decode()

            if err_line:
                if RE_DEP_NOTFOUND.findall(err_line):
                    not_found = True

    if not_found:
        raise PackageNotFoundException(name)

    depends_on = set()
    for out in new_subprocess(['grep', '-Po', 'Depends\s+On\s+:\s\K(.+)'], stdin=dep_info.stdout).stdout:
        if out:
            line = out.decode().strip()

            if line:
                depends_on.update([d for d in line.split(' ') if d and d.lower() != 'none'])

    return depends_on


def sync_databases(root_password: str, force: bool = False) -> SimpleProcess:
    return SimpleProcess(cmd=['pacman', '-Sy{}'.format('y' if force else '')],
                         root_password=root_password)


def get_version_for_not_installed(pkgname: str) -> str:
    output = run_cmd('pacman -Ss {}'.format(pkgname), print_error=False)

    if output:
        return output.split('\n')[0].split(' ')[1].strip()


def map_repositories(pkgnames: Iterable[str] = None) -> Dict[str, str]:
    info = run_cmd('pacman -Si {}'.format(' '.join(pkgnames) if pkgnames else ''), print_error=False, ignore_return_code=True)
    if info:
        repos = re.findall(r'(Name|Repository)\s*:\s*(.+)', info)

        if repos:
            return {repos[idx+1][1].strip(): repo_data[1].strip() for idx, repo_data in enumerate(repos) if idx % 2 == 0}

    return {}


def list_repository_updates() -> Dict[str, str]:
    output = run_cmd('pacman -Qu')
    res = {}
    if output:
        for line in output.split('\n'):
            if line:
                line_split = line.split(' ')
                res[line_split[0]] = line_split[-1]
    return res


def map_sorting_data(pkgnames: List[str]) -> Dict[str, dict]:
    allinfo = new_subprocess(['pacman', '-Qi', *pkgnames]).stdout

    pkgs, current_pkg = {}, {}
    mapped_attrs = 0
    for out in new_subprocess(["grep", "-Po", "(Name|Provides|Depends On)\s*:\s*\K(.+)"], stdin=allinfo).stdout:
        if out:
            line = out.decode().strip()

            if line:
                if mapped_attrs == 0:
                    current_pkg['name'] = line
                elif mapped_attrs == 1:
                    provides = set() if line == 'None' else set(line.split(' '))
                    provides.add(current_pkg['name'])
                    current_pkg['provides'] = provides
                elif mapped_attrs == 2:
                    current_pkg['depends'] = line.split(':')[1].strip()
                    pkgs[current_pkg['name']] = current_pkg
                    del current_pkg['name']

                    mapped_attrs = 0
                    current_pkg = {}
    return pkgs


def get_build_date(pkgname: str) -> str:
    output = run_cmd('pacman -Qi {}'.format(pkgname))

    if output:
        bdate_line = [l for l in output.split('\n') if l.startswith('Build Date')]

        if bdate_line:
            return ':'.join(bdate_line[0].split(':')[1:]).strip()


def search(words: str) -> Dict[str, dict]:
    output = run_cmd('pacman -Ss ' + words, print_error=False)

    if output:
        found, current = {}, {}
        for l in output.split('\n'):
            if l:
                if l.startswith(' '):
                    current['description'] = l.strip()
                    found[current['name']] = current
                    del current['name']
                    current = None
                else:
                    if current is None:
                        current = {}

                    repo_split = l.split('/')
                    current['repository'] = repo_split[0]

                    data_split = repo_split[1].split(' ')
                    current['name'] = data_split[0]

                    version = data_split[1].split(':')
                    current['version'] = version[0] if len(version) == 1 else version[1]
        return found


def get_databases() -> Set[str]:
    with open('/etc/pacman.conf') as f:
        conf_str = f.read()

    return {db for db in re.findall(r'[\n|\s]+\[(\w+)\]', conf_str) if db != 'options'}


def can_refresh_mirrors() -> bool:
    output = run_cmd('which pacman-mirrors', print_error=False)
    return True if output else False


def refresh_mirrors(root_password: str) -> SimpleProcess:
    return SimpleProcess(cmd=['pacman-mirrors', '-g'], root_password=root_password)


def update_mirrors(root_password: str, countries: List[str]) -> SimpleProcess:
    return SimpleProcess(cmd=['pacman-mirrors', '-c', ','.join(countries)], root_password=root_password)


def sort_fastest_mirrors(root_password: str, limit: int) -> SimpleProcess:
    cmd = ['pacman-mirrors', '--fasttrack']

    if limit > 0:
        cmd.append(str(limit))

    return SimpleProcess(cmd=cmd, root_password=root_password)


def list_mirror_countries() -> List[str]:
    output = run_cmd('pacman-mirrors -l')

    if output:
        return [c for c in output.split('\n') if c]


def get_current_mirror_countries() -> List[str]:
    output = run_cmd('pacman-mirrors -lc').strip()
    return ['all'] if not output else [c for c in output.split('\n') if c]


def is_mirrors_available() -> bool:
    return bool(run_cmd('which pacman-mirrors', print_error=False))


def map_update_sizes(pkgs: List[str]) -> Dict[str, int]:  # bytes:
    output = run_cmd('pacman -Si {}'.format(' '.join(pkgs)))

    if output:
        return {pkgs[idx]: size_to_byte(float(size[0]), size[1]) for idx, size in enumerate(RE_INSTALLED_SIZE.findall(output))}

    return {}


def map_download_sizes(pkgs: List[str]) -> Dict[str, int]:  # bytes:
    output = run_cmd('pacman -Si {}'.format(' '.join(pkgs)))

    if output:
        return {pkgs[idx]: size_to_byte(float(size[0]), size[1]) for idx, size in enumerate(RE_DOWNLOAD_SIZE.findall(output))}

    return {}


def get_installed_size(pkgs: List[str]) -> Dict[str, int]:  # bytes
    output = run_cmd('pacman -Qi {}'.format(' '.join(pkgs)))

    if output:
        return {pkgs[idx]: size_to_byte(float(size[0]), size[1]) for idx, size in enumerate(RE_INSTALLED_SIZE.findall(output))}

    return {}


def upgrade_system(root_password: str) -> SimpleProcess:
    return SimpleProcess(cmd=['pacman', '-Syyu', '--noconfirm'], root_password=root_password)


def fill_provided_map(key: str, val: str, output: dict):
    current_val = output.get(key)

    if current_val is None:
        output[key] = {val}
    else:
        current_val.add(val)


def map_provided(remote: bool = False, pkgs: Iterable[str] = None) -> Dict[str, Set[str]]:
    output = run_cmd('pacman -{}i {}'.format('S' if remote else 'Q', ' '.join(pkgs) if pkgs else ''))

    if output:
        provided_map = {}
        latest_name, latest_version, provided = None, None, False

        for l in output.split('\n'):
            if l:
                if l[0] != ' ':
                    line = l.strip()
                    field_sep_idx = line.index(':')
                    field = line[0:field_sep_idx].strip()
                    val = line[field_sep_idx + 1:].strip()

                    if field == 'Name':
                        latest_name = val
                    elif field == 'Version':
                        latest_version = val.split('=')[0]
                    elif field == 'Provides':
                        fill_provided_map(latest_name, latest_name, provided_map)
                        fill_provided_map('{}={}'.format(latest_name, latest_version), latest_name, provided_map)

                        if val != 'None':
                            for w in val.split(' '):
                                if w:
                                    word = w.strip()
                                    fill_provided_map(word, latest_name, provided_map)

                                    word_split = word.split('=')

                                    if word_split[0] != word:
                                        fill_provided_map(word_split[0], latest_name, provided_map)
                        else:
                            provided = True

                    elif provided:
                        latest_name = None
                        latest_version = None
                        provided = False

                elif provided:
                    for w in l.split(' '):
                        if w:
                            word = w.strip()
                            fill_provided_map(word, latest_name, provided_map)

                            word_split = word.split('=')

                            if word_split[0] != word:
                                fill_provided_map(word_split[0], latest_name, provided_map)

        return provided_map


def list_download_data(pkgs: Iterable[str]) -> List[Dict[str, str]]:
    _, output = system.run(['pacman', '-Si', *pkgs])

    if output:
        res = []
        data = {'a': None, 'v': None, 'r': None, 'n': None}

        for l in output.split('\n'):
            if l:
                if l[0] != ' ':
                    line = l.strip()
                    field_sep_idx = line.index(':')
                    field = line[0:field_sep_idx].strip()
                    val = line[field_sep_idx + 1:].strip()

                    if field == 'Repository':
                        data['r'] = val
                    elif field == 'Name':
                        data['n'] = val
                    elif field == 'Version':
                        data['v'] = val.split('=')[0]
                    elif field == 'Architecture':
                        data['a'] = val
                    elif data.get('a'):
                        res.append(data)
                        data = {'a': None, 'v': None, 'r': None, 'n': None}

        return res


def map_updates_data(pkgs: Iterable[str], files: bool = False) -> dict:
    if files:
        output = run_cmd('pacman -Qi -p {}'.format(' '.join(pkgs)))
    else:
        output = run_cmd('pacman -Si {}'.format(' '.join(pkgs)))

    if output:
        res = {}
        latest_name = None
        data = {'ds': None, 's': None, 'v': None, 'c': None, 'p': None, 'd': None, 'r': None}
        latest_field = None

        for l in output.split('\n'):
            if l:
                if l[0] != ' ':
                    line = l.strip()
                    field_sep_idx = line.index(':')
                    field = line[0:field_sep_idx].strip()
                    val = line[field_sep_idx + 1:].strip()

                    if field == 'Repository':
                        data['r'] = val
                        latest_field = 'r'
                    elif field == 'Name':
                        latest_name = val
                        latest_field = 'n'
                    elif field == 'Version':
                        data['v'] = val.split('=')[0]
                        latest_field = 'v'
                    elif field == 'Provides':
                        latest_field = 'p'
                        data['p'] = {latest_name, '{}={}'.format(latest_name, data['v'])}
                        if val != 'None':
                            for w in val.split(' '):
                                if w:
                                    word = w.strip()
                                    data['p'].add(word)

                                    word_split = word.split('=')

                                    if word_split[0] != word:
                                        data['p'].add(word_split[0])
                    elif field == 'Depends On':
                        val = val.strip()

                        if val == 'None':
                            data['d'] = None
                        else:
                            data['d'] = {w.strip().split(':')[0].strip() for w in val.split(' ') if w}
                            latest_field = 'd'
                    elif field == 'Conflicts With':
                        if val == 'None':
                            data['c'] = None
                        else:
                            data['c'] = {w.strip() for w in val.split(' ') if w}

                        latest_field = 'c'
                    elif field == 'Download Size':
                        size = val.split(' ')
                        data['ds'] = size_to_byte(float(size[0]), size[1])
                        latest_field = 'ds'
                    elif field == 'Installed Size':
                        size = val.split(' ')
                        data['s'] = size_to_byte(float(size[0]), size[1])
                        latest_field = 's'
                    elif latest_name and latest_field == 's':
                        res[latest_name] = data
                        latest_name = None
                        latest_field = None
                        data = {'ds': None, 's': None, 'c': None, 'p': None, 'd': None, 'r': None,  'v': None}
                    else:
                        latest_field = None

                elif latest_field and latest_field in ('p', 'c', 'd'):
                    if latest_field == 'p':
                        for w in l.split(' '):
                            if w:
                                word = w.strip()
                                data['p'].add(word)

                                word_split = word.split('=')

                                if word_split[0] != word:
                                    data['p'].add(word_split[0])
                    else:
                        data[latest_field].update((w.strip() for w in l.split(' ') if w))

        return res


def upgrade_several(pkgnames: Iterable[str], root_password: str, overwrite_conflicting_files: bool = False) -> SimpleProcess:
    cmd = ['pacman', '-S', *pkgnames, '--noconfirm']

    if overwrite_conflicting_files:
        cmd.append('--overwrite=*')

    return SimpleProcess(cmd=cmd,
                         root_password=root_password,
                         error_phrases={'error: failed to prepare transaction', 'error: failed to commit transaction', 'error: target not found'},
                         shell=True)


def download(root_password: str, *pkgnames: str) -> SimpleProcess:
    return SimpleProcess(cmd=['pacman', '-Swdd', *pkgnames, '--noconfirm'],
                         root_password=root_password,
                         error_phrases={'error: failed to prepare transaction', 'error: failed to commit transaction', 'error: target not found'},
                         shell=True)


def remove_several(pkgnames: Iterable[str], root_password: str, skip_checks: bool = False) -> SimpleProcess:
    cmd = ['pacman', '-R', *pkgnames, '--noconfirm']

    if skip_checks:
        cmd.append('-dd')

    return SimpleProcess(cmd=cmd, root_password=root_password, wrong_error_phrases={'warning:'}, shell=True)


def map_optional_deps(names: Iterable[str], remote: bool, not_installed: bool = False) -> Dict[str, Dict[str, str]]:
    output = run_cmd('pacman -{}i {}'.format('S' if remote else 'Q', ' '.join(names)))
    res = {}
    if output:
        latest_name, deps = None, None

        for l in output.split('\n'):
            if l:
                if l[0] != ' ':
                    line = l.strip()
                    field_sep_idx = line.index(':')
                    field = line[0:field_sep_idx].strip()

                    if field == 'Name':
                        val = line[field_sep_idx + 1:].strip()
                        latest_name = val
                    elif field == 'Optional Deps':
                        val = line[field_sep_idx + 1:].strip()
                        deps = {}
                        if val != 'None':
                            if ':' in val:
                                dep_info = val.split(':')
                                desc = dep_info[1].strip()

                                if desc and not_installed and '[installed]' in desc:
                                    continue

                                deps[dep_info[0].strip()] = desc
                            else:
                                sev_deps = {dep.strip(): '' for dep in val.split(' ') if dep and (not not_installed or '[installed]' not in dep)}
                                deps.update(sev_deps)
                    elif latest_name and deps is not None:
                        res[latest_name] = deps
                        latest_name, deps = None, None

                elif latest_name and deps is not None:
                    if ':' in l:
                        dep_info = l.split(':')
                        desc = dep_info[1].strip()

                        if desc and not_installed and '[installed]' in desc:
                            continue

                        deps[dep_info[0].strip()] = desc
                    else:
                        sev_deps = {dep.strip(): '' for dep in l.split(' ') if dep and (not not_installed or '[installed]' not in dep)}
                        deps.update(sev_deps)

    return res


def map_all_deps(names: Iterable[str], only_installed: bool = False) -> Dict[str, Set[str]]:
    output = run_cmd('pacman -Qi {}'.format(' '.join(names)))

    if output:
        res = {}
        deps_fields = {'Depends On', 'Optional Deps'}
        latest_name, deps, latest_field = None, None, None

        for l in output.split('\n'):
            if l:
                if l[0] != ' ':
                    line = l.strip()
                    field_sep_idx = line.index(':')
                    field = line[0:field_sep_idx].strip()

                    if field == 'Name':
                        latest_field = field
                        val = line[field_sep_idx + 1:].strip()
                        latest_name = val
                        deps = None
                    elif field in deps_fields:
                        latest_field = field
                        val = line[field_sep_idx + 1:].strip()
                        opt_deps = latest_field == 'Optional Deps'

                        if deps is None:
                            deps = set()

                        if val != 'None':
                            if ':' in val:
                                dep_info = val.split(':')
                                desc = dep_info[1].strip()

                                if desc and opt_deps and only_installed and '[installed]' not in desc:
                                    continue

                                deps.add(dep_info[0].strip())
                            else:
                                deps.update({dep.strip() for dep in val.split(' ') if dep})

                    elif latest_name and deps is not None:
                        res[latest_name] = deps
                        latest_name, deps, latest_field = None, None, None

                elif latest_name and deps is not None:
                    opt_deps = latest_field == 'Optional Deps'

                    if ':' in l:
                        dep_info = l.split(':')
                        desc = dep_info[1].strip()

                        if desc and opt_deps and only_installed and '[installed]' not in desc:
                            continue

                        deps.add(dep_info[0].strip())
                    else:
                        deps.update({dep.strip() for dep in l.split(' ') if dep})

        return res


def map_required_dependencies(*names: str) -> Dict[str, Set[str]]:
    output = run_cmd('pacman -Qi {}'.format(' '.join(names) if names else ''))

    if output:
        res = {}
        latest_name, deps, latest_field = None, None, None

        for l in output.split('\n'):
            if l:
                if l[0] != ' ':
                    line = l.strip()
                    field_sep_idx = line.index(':')
                    field = line[0:field_sep_idx].strip()

                    if field == 'Name':
                        val = line[field_sep_idx + 1:].strip()
                        latest_name = val
                        deps = None
                    elif field == 'Depends On':
                        val = line[field_sep_idx + 1:].strip()

                        if deps is None:
                            deps = set()

                        if val != 'None':
                            if ':' in val:
                                dep_info = val.split(':')
                                deps.add(dep_info[0].strip())
                            else:
                                deps.update({dep.strip() for dep in val.split(' ') if dep})

                    elif latest_name and deps is not None:
                        res[latest_name] = deps
                        latest_name, deps, latest_field = None, None, None

                elif latest_name and deps is not None:
                    if ':' in l:
                        dep_info = l.split(':')
                        deps.add(dep_info[0].strip())
                    else:
                        deps.update({dep.strip() for dep in l.split(' ') if dep})

        return res


def get_cache_dir() -> str:
    dir_pattern = re.compile(r'.*CacheDir\s*=\s*.+')

    if os.path.exists('/etc/pacman.conf'):
        with open('/etc/pacman.conf') as f:
            config_str = f.read()

        cache_dirs = []

        for string in dir_pattern.findall(config_str):
            if not string.strip().startswith('#'):
                cache_dirs.append(string.split('=')[1].strip())

        if cache_dirs:
            if cache_dirs[-1][-1] == '/':
                return cache_dirs[-1][0:-1]
            else:
                return cache_dirs[-1]
        else:
            return '/var/cache/pacman/pkg'


def map_required_by(names: Iterable[str] = None) -> Dict[str, Set[str]]:
    output = run_cmd('pacman -Qi {}'.format(' '.join(names) if names else ''))

    if output:
        res = {}
        latest_name, required = None, None

        for l in output.split('\n'):
            if l:
                if l[0] != ' ':
                    line = l.strip()
                    field_sep_idx = line.index(':')
                    field = line[0:field_sep_idx].strip()

                    if field == 'Name':
                        val = line[field_sep_idx + 1:].strip()
                        latest_name = val
                    elif field == 'Required By':
                        val = line[field_sep_idx + 1:].strip()
                        required = set()
                        if val != 'None':
                            required.update((d for d in val.split(' ') if d))

                    elif latest_name and required is not None:
                        res[latest_name] = required
                        latest_name, required = None, None

                elif latest_name and required is not None:
                    required.update(required.update((d for d in l.strip().split(' ') if d)))

        return res


def map_conflicts_with(names: Iterable[str], remote: bool) -> Dict[str, Set[str]]:
    output = run_cmd('pacman -{}i {}'.format('S' if remote else 'Q', ' '.join(names)))

    if output:
        res = {}
        latest_name, conflicts = None, None

        for l in output.split('\n'):
            if l:
                if l[0] != ' ':
                    line = l.strip()
                    field_sep_idx = line.index(':')
                    field = line[0:field_sep_idx].strip()

                    if field == 'Name':
                        val = line[field_sep_idx + 1:].strip()
                        latest_name = val
                    elif field == 'Conflicts With':
                        val = line[field_sep_idx + 1:].strip()
                        conflicts = set()
                        if val != 'None':
                            conflicts.update((d for d in val.split(' ') if d))

                    elif latest_name and conflicts is not None:
                        res[latest_name] = conflicts
                        latest_name, conflicts = None, None

                elif latest_name and conflicts is not None:
                    conflicts.update(conflicts.update((d for d in l.strip().split(' ') if d)))

        return res


def _list_unnecessary_deps(pkgs: Iterable[str], already_checked: Set[str], all_provided: Dict[str, Set[str]], recursive: bool = False) -> Set[str]:
    output = run_cmd('pacman -Qi {}'.format(' '.join(pkgs)))

    if output:
        res = set()
        deps_field = False

        for l in output.split('\n'):
            if l:
                if l[0] != ' ':
                    line = l.strip()
                    field_sep_idx = line.index(':')
                    field = line[0:field_sep_idx].strip()

                    if field == 'Depends On':
                        deps_field = True
                        val = line[field_sep_idx + 1:].strip()

                        if val != 'None':
                            if ':' in val:
                                dep_info = val.split(':')

                                real_deps = all_provided.get(dep_info[0].strip())

                                if real_deps:
                                    res.update(real_deps)
                            else:
                                for dep in val.split(' '):
                                    if dep:
                                        real_deps = all_provided.get(dep.strip())

                                        if real_deps:
                                            res.update(real_deps)

                    elif deps_field:
                        latest_field = False

                elif deps_field:
                    if ':' in l:
                        dep_info = l.split(':')

                        real_deps = all_provided.get(dep_info[0].strip())

                        if real_deps:
                            res.update(real_deps)
                    else:
                        for dep in l.split(' '):
                            if dep:
                                real_deps = all_provided.get(dep.strip())

                                if real_deps:
                                    res.update(real_deps)

        if res:
            res = {dep for dep in res if dep not in already_checked}
            already_checked.update(res)

            if recursive and res:
                subdeps = _list_unnecessary_deps(res, already_checked, all_provided)

                if subdeps:
                    res.update(subdeps)

        return res


def list_unnecessary_deps(pkgs: Iterable[str], all_provided: Dict[str, Set[str]] = None) -> Set[str]:
    all_checked = set(pkgs)
    all_deps = _list_unnecessary_deps(pkgs, all_checked, map_provided(remote=False) if not all_provided else all_provided, recursive=True)

    unnecessary = set(pkgs)
    if all_deps:
        requirements_map = map_required_by(all_deps)

        to_clean = set()
        for dep, required_by in requirements_map.items():
            if not required_by or not required_by.difference(unnecessary):
                unnecessary.add(dep)
                to_clean.add(dep)
            elif required_by.difference(all_checked):  # checking if there are requirements outside the context
                to_clean.add(dep)

        if to_clean:
            for dep in to_clean:
                del requirements_map[dep]

        if requirements_map:
            while True:
                to_clean = set()
                for dep, required_by in requirements_map.items():
                    if not required_by.difference(unnecessary):
                        unnecessary.add(dep)
                        to_clean.add(dep)

                if to_clean:
                    for dep in to_clean:
                        del requirements_map[dep]
                else:
                    break

            if requirements_map:  # if it reaches this points it is possible to exist mutual dependent packages
                for dep, required_by in requirements_map.items():
                    if not required_by.difference({*requirements_map.keys(), *unnecessary}):
                        unnecessary.add(dep)

    return unnecessary.difference(pkgs)


def list_installed_names() -> Set[str]:
    output = run_cmd('pacman -Qq', print_error=False)
    return {name.strip() for name in output.split('\n') if name} if output else set()


def list_available_mirrors() -> List[str]:
    _, output = system.run(['pacman-mirrors', '--status', '--no-color'])

    if output:
        mirrors = RE_AVAILABLE_MIRRORS.findall(output)

        if mirrors:
            mirrors.sort(key=lambda o: o[0])
            return [m[1] for m in mirrors]


def get_mirrors_branch() -> str:
    _, output = system.run(['pacman-mirrors', '-G'])
    return output.strip()


def get_packages_to_sync_first() -> Set[str]:
    if os.path.exists('/etc/pacman.conf'):
        with open('/etc/pacman.conf') as f:
            to_sync_first = RE_PACMAN_SYNC_FIRST.findall(f.read())

            if to_sync_first:
                return {s.strip() for s in to_sync_first[0].split(' ') if s and s.strip()}

    return set()