# vim: ft=python fileencoding=utf-8 sts=4 sw=4 et:

# Copyright 2014-2018 Florian Bruhin (The Compiler) <mail@qutebrowser.org>
#
# This file is part of qutebrowser.
#
# qutebrowser is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# qutebrowser is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with qutebrowser.  If not, see <http://www.gnu.org/licenses/>.

"""Misc. utility commands exposed to the user."""

import functools
import os
import signal
import traceback

try:
    import hunter
except ImportError:
    hunter = None

import sip
from PyQt5.QtCore import QUrl
# so it's available for :debug-pyeval
from PyQt5.QtWidgets import QApplication  # pylint: disable=unused-import

from qutebrowser.browser import qutescheme
from qutebrowser.utils import log, objreg, usertypes, message, debug, utils
from qutebrowser.commands import cmdutils, runners, cmdexc
from qutebrowser.config import config, configdata
from qutebrowser.misc import consolewidget
from qutebrowser.utils.version import pastebin_version


@cmdutils.register(maxsplit=1, no_cmd_split=True, no_replace_variables=True)
@cmdutils.argument('win_id', win_id=True)
def later(ms: int, command, win_id):
    """Execute a command after some time.

    Args:
        ms: How many milliseconds to wait.
        command: The command to run, with optional args.
    """
    if ms < 0:
        raise cmdexc.CommandError("I can't run something in the past!")
    commandrunner = runners.CommandRunner(win_id)
    app = objreg.get('app')
    timer = usertypes.Timer(name='later', parent=app)
    try:
        timer.setSingleShot(True)
        try:
            timer.setInterval(ms)
        except OverflowError:
            raise cmdexc.CommandError("Numeric argument is too large for "
                                      "internal int representation.")
        timer.timeout.connect(
            functools.partial(commandrunner.run_safely, command))
        timer.timeout.connect(timer.deleteLater)
        timer.start()
    except:
        timer.deleteLater()
        raise


@cmdutils.register(maxsplit=1, no_cmd_split=True, no_replace_variables=True)
@cmdutils.argument('win_id', win_id=True)
def repeat(times: int, command, win_id):
    """Repeat a given command.

    Args:
        times: How many times to repeat.
        command: The command to run, with optional args.
    """
    if times < 0:
        raise cmdexc.CommandError("A negative count doesn't make sense.")
    commandrunner = runners.CommandRunner(win_id)
    for _ in range(times):
        commandrunner.run_safely(command)


@cmdutils.register(maxsplit=1, no_cmd_split=True, no_replace_variables=True)
@cmdutils.argument('win_id', win_id=True)
@cmdutils.argument('count', count=True)
def run_with_count(count_arg: int, command, win_id, count=1):
    """Run a command with the given count.

    If run_with_count itself is run with a count, it multiplies count_arg.

    Args:
        count_arg: The count to pass to the command.
        command: The command to run, with optional args.
        count: The count that run_with_count itself received.
    """
    runners.CommandRunner(win_id).run(command, count_arg * count)


@cmdutils.register()
def message_error(text):
    """Show an error message in the statusbar.

    Args:
        text: The text to show.
    """
    message.error(text)


@cmdutils.register()
@cmdutils.argument('count', count=True)
def message_info(text, count=1):
    """Show an info message in the statusbar.

    Args:
        text: The text to show.
        count: How many times to show the message
    """
    for _ in range(count):
        message.info(text)


@cmdutils.register()
def message_warning(text):
    """Show a warning message in the statusbar.

    Args:
        text: The text to show.
    """
    message.warning(text)


@cmdutils.register()
def clear_messages():
    """Clear all message notifications."""
    message.global_bridge.clear_messages.emit()


@cmdutils.register(debug=True)
@cmdutils.argument('typ', choices=['exception', 'segfault'])
def debug_crash(typ='exception'):
    """Crash for debugging purposes.

    Args:
        typ: either 'exception' or 'segfault'.
    """
    if typ == 'segfault':
        os.kill(os.getpid(), signal.SIGSEGV)
        raise Exception("Segfault failed (wat.)")
    else:
        raise Exception("Forced crash")


@cmdutils.register(debug=True)
def debug_all_objects():
    """Print a list of  all objects to the debug log."""
    s = debug.get_all_objects()
    log.misc.debug(s)


@cmdutils.register(debug=True)
def debug_cache_stats():
    """Print LRU cache stats."""
    prefix_info = configdata.is_valid_prefix.cache_info()
    # pylint: disable=protected-access
    render_stylesheet_info = config._render_stylesheet.cache_info()
    # pylint: enable=protected-access

    history_info = None
    try:
        from PyQt5.QtWebKit import QWebHistoryInterface
        interface = QWebHistoryInterface.defaultInterface()
        if interface is not None:
            history_info = interface.historyContains.cache_info()
    except ImportError:
        pass

    tabbed_browser = objreg.get('tabbed-browser', scope='window',
                                window='last-focused')
    # pylint: disable=protected-access
    tab_bar = tabbed_browser.tabBar()
    tabbed_browser_info = tab_bar._minimum_tab_size_hint_helper.cache_info()
    # pylint: enable=protected-access

    log.misc.debug('is_valid_prefix: {}'.format(prefix_info))
    log.misc.debug('_render_stylesheet: {}'.format(render_stylesheet_info))
    log.misc.debug('history: {}'.format(history_info))
    log.misc.debug('tab width cache: {}'.format(tabbed_browser_info))


@cmdutils.register(debug=True)
def debug_console():
    """Show the debugging console."""
    try:
        con_widget = objreg.get('debug-console')
    except KeyError:
        log.misc.debug('initializing debug console')
        con_widget = consolewidget.ConsoleWidget()
        objreg.register('debug-console', con_widget)

    if con_widget.isVisible():
        log.misc.debug('hiding debug console')
        con_widget.hide()
    else:
        log.misc.debug('showing debug console')
        con_widget.show()


@cmdutils.register(debug=True, maxsplit=0, no_cmd_split=True)
def debug_trace(expr=""):
    """Trace executed code via hunter.

    Args:
        expr: What to trace, passed to hunter.
    """
    if hunter is None:
        raise cmdexc.CommandError("You need to install 'hunter' to use this "
                                  "command!")
    try:
        eval('hunter.trace({})'.format(expr))
    except Exception as e:
        raise cmdexc.CommandError("{}: {}".format(e.__class__.__name__, e))


@cmdutils.register(maxsplit=0, debug=True, no_cmd_split=True)
def debug_pyeval(s, file=False, quiet=False):
    """Evaluate a python string and display the results as a web page.

    Args:
        s: The string to evaluate.
        file: Interpret s as a path to file, also implies --quiet.
        quiet: Don't show the output in a new tab.
    """
    if file:
        quiet = True
        path = os.path.expanduser(s)
        try:
            with open(path, 'r', encoding='utf-8') as f:
                s = f.read()
        except OSError as e:
            raise cmdexc.CommandError(str(e))
        try:
            exec(s)
            out = "No error"
        except Exception:
            out = traceback.format_exc()
    else:
        try:
            r = eval(s)
            out = repr(r)
        except Exception:
            out = traceback.format_exc()

    qutescheme.pyeval_output = out
    if quiet:
        log.misc.debug("pyeval output: {}".format(out))
    else:
        tabbed_browser = objreg.get('tabbed-browser', scope='window',
                                    window='last-focused')
        tabbed_browser.openurl(QUrl('qute://pyeval'), newtab=True)


@cmdutils.register(debug=True)
def debug_set_fake_clipboard(s=None):
    """Put data into the fake clipboard and enable logging, used for tests.

    Args:
        s: The text to put into the fake clipboard, or unset to enable logging.
    """
    if s is None:
        utils.log_clipboard = True
    else:
        utils.fake_clipboard = s


@cmdutils.register()
@cmdutils.argument('win_id', win_id=True)
@cmdutils.argument('count', count=True)
def repeat_command(win_id, count=None):
    """Repeat the last executed command.

    Args:
        count: Which count to pass the command.
    """
    mode_manager = objreg.get('mode-manager', scope='window', window=win_id)
    if mode_manager.mode not in runners.last_command:
        raise cmdexc.CommandError("You didn't do anything yet.")
    cmd = runners.last_command[mode_manager.mode]
    commandrunner = runners.CommandRunner(win_id)
    commandrunner.run(cmd[0], count if count is not None else cmd[1])


@cmdutils.register(debug=True, name='debug-log-capacity')
def log_capacity(capacity: int):
    """Change the number of log lines to be stored in RAM.

    Args:
       capacity: Number of lines for the log.
    """
    if capacity < 0:
        raise cmdexc.CommandError("Can't set a negative log capacity!")
    else:
        log.ram_handler.change_log_capacity(capacity)


@cmdutils.register(debug=True)
@cmdutils.argument('level', choices=sorted(
    (level.lower() for level in log.LOG_LEVELS),
    key=lambda e: log.LOG_LEVELS[e.upper()]))
def debug_log_level(level: str):
    """Change the log level for console logging.

    Args:
        level: The log level to set.
    """
    log.change_console_formatter(log.LOG_LEVELS[level.upper()])
    log.console_handler.setLevel(log.LOG_LEVELS[level.upper()])


@cmdutils.register(debug=True)
def debug_log_filter(filters: str):
    """Change the log filter for console logging.

    Args:
        filters: A comma separated list of logger names. Can also be "none" to
                 clear any existing filters.
    """
    if log.console_filter is None:
        raise cmdexc.CommandError("No log.console_filter. Not attached "
                                  "to a console?")

    if filters.strip().lower() == 'none':
        log.console_filter.names = None
        return

    if not set(filters.split(',')).issubset(log.LOGGER_NAMES):
        raise cmdexc.CommandError("filters: Invalid value {} - expected one "
                                  "of: {}".format(filters,
                                                  ', '.join(log.LOGGER_NAMES)))

    log.console_filter.names = filters.split(',')


@cmdutils.register()
@cmdutils.argument('current_win_id', win_id=True)
def window_only(current_win_id):
    """Close all windows except for the current one."""
    for win_id, window in objreg.window_registry.items():

        # We could be in the middle of destroying a window here
        if sip.isdeleted(window):
            continue

        if win_id != current_win_id:
            window.close()


@cmdutils.register()
def nop():
    """Do nothing."""
    return


@cmdutils.register()
@cmdutils.argument('win_id', win_id=True)
def version(win_id, paste=False):
    """Show version information.

    Args:
        paste: Paste to pastebin.
    """
    tabbed_browser = objreg.get('tabbed-browser', scope='window',
                                window=win_id)
    tabbed_browser.openurl(QUrl('qute://version'), newtab=True)

    if paste:
        pastebin_version()
