#!/usr/bin/env python
# License: GPLv3 Copyright: 2019, Kovid Goyal <kovid at kovidgoyal.net>


from typing import Any, Dict, Iterable, List, NamedTuple, Optional, Sequence

from .boss import Boss
from .child import Child
from .cli import parse_args
from .cli_stub import LaunchCLIOptions
from .constants import resolve_custom_file
from .fast_data_types import (
    get_options, patch_color_profiles, set_clipboard_string
)
from .options.utils import env as parse_env
from .tabs import Tab
from .types import run_once
from .utils import find_exe, read_shell_environment, set_primary_selection, log_error
from .window import Watchers, Window

try:
    from typing import TypedDict
except ImportError:
    TypedDict = dict


class LaunchSpec(NamedTuple):
    opts: LaunchCLIOptions
    args: List[str]


@run_once
def options_spec() -> str:
    return '''
--window-title --title
The title to set for the new window. By default, title is controlled by the
child process.


--tab-title
The title for the new tab if launching in a new tab. By default, the title
of the active window in the tab is used as the tab title.


--type
type=choices
default=window
choices=window,tab,os-window,overlay,background,clipboard,primary
Where to launch the child process, in a new kitty window in the current tab,
a new tab, or a new OS window or an overlay over the current window.
Note that if the current window already has an overlay, then it will
open a new window. The value of background means the process will be
run in the background. The values clipboard and primary are meant
to work with :option:`launch --stdin-source` to copy data to the system
clipboard or primary selection.


--keep-focus --dont-take-focus
type=bool-set
Keep the focus on the currently active window instead of switching
to the newly opened window.


--cwd
The working directory for the newly launched child. Use the special value
:code:`current` to use the working directory of the currently active window.


--env
type=list
Environment variables to set in the child process. Can be specified multiple
times to set different environment variables.  Syntax: :code:`name=value`.
Using :code:`name=` will set to empty string and just :code:`name` will
remove the environment variable.


--copy-colors
type=bool-set
Set the colors of the newly created window to be the same as the colors in the
currently active window.


--copy-cmdline
type=bool-set
Ignore any specified command line and instead use the command line from the
currently active window.


--copy-env
type=bool-set
Copy the environment variables from the currently active window into the
newly launched child process. Note that most shells only set environment
variables for child processes, so this will only copy the environment
variables that the shell process itself has not the environment variables
child processes inside the shell see. To copy that enviroment, use the
kitty remote control feature with :code:`kitty @launch --copy-env`.


--location
type=choices
default=default
choices=first,after,before,neighbor,last,vsplit,hsplit,default
Where to place the newly created window when it is added to a tab which
already has existing windows in it. :code:`after` and :code:`before` place the new
window before or after the active window. :code:`neighbor` is a synonym for :code:`after`.
Also applies to creating a new tab, where the value of :code:`after`
will cause the new tab to be placed next to the current tab instead of at the end.
The values of :code:`vsplit` and :code:`hsplit` are only used by the :code:`splits`
layout and control if the new window is placed in a vertical or horizontal split
with the currently active window. The default is to place the window in a
layout dependent manner, typically, after the currently active window.


--allow-remote-control
type=bool-set
Programs running in this window can control kitty (if remote control is
enabled). Note that any program with the right level of permissions can still
write to the pipes of any other program on the same computer and therefore can
control kitty. It can, however, be useful to block programs running on other
computers (for example, over ssh) or as other users.


--stdin-source
type=choices
default=none
choices=none,@selection,@screen,@screen_scrollback,@alternate,@alternate_scrollback,@last_cmd_output
Pass the screen contents as :code:`STDIN` to the child process. :code:`@selection` is
the currently selected text. :code:`@screen` is the contents of the currently active
window. :code:`@screen_scrollback` is the same as :code:`@screen`, but includes the
scrollback buffer as well. :code:`@alternate` is the secondary screen of the current
active window. For example if you run a full screen terminal application, the
secondary screen will be the screen you return to when quitting the
application. :code:`@last_cmd_output` is the output from the last command run in the shell,
this needs :ref:`shell_integration` to work.


--stdin-add-formatting
type=bool-set
When using :option:`launch --stdin-source` add formatting escape codes, without this
only plain text will be sent.


--stdin-add-line-wrap-markers
type=bool-set
When using :option:`launch --stdin-source` add a carriage return at every line wrap
location (where long lines are wrapped at screen edges). This is useful if you
want to pipe to program that wants to duplicate the screen layout of the
screen.


--marker
Create a marker that highlights text in the newly created window. The syntax is
the same as for the :code:`toggle_marker` map action (see :doc:`/marks`).


--os-window-class
Set the WM_CLASS property on X11 and the application id property on Wayland for
the newly created OS Window when using :option:`launch --type`=os-window.
Defaults to whatever is used by the parent kitty process, which in turn
defaults to :code:`kitty`.


--os-window-name
Set the WM_NAME property on X11 for the newly created OS Window when using
:option:`launch --type`=os-window. Defaults to :option:`launch --os-window-class`.


--os-window-title
Set the title for the newly created OS window. This title will override any
titles set by programs running in kitty.


--color
type=list
Change colors in the newly launched window. You can either specify a path to a .conf
file with the same syntax as kitty.conf to read the colors from, or specify them
individually, for example: ``--color background=white`` ``--color foreground=red``


--watcher -w
type=list
Path to a python file. Appropriately named functions in this file will be called
for various events, such as when the window is resized, focused or closed. See the section
on watchers in the launch command documentation: :ref:`watchers`. Relative paths are
resolved relative to the kitty config directory. Global watchers for all windows can be
specified with :opt:`watcher`.
'''


def parse_launch_args(args: Optional[Sequence[str]] = None) -> LaunchSpec:
    args = list(args or ())
    try:
        opts, args = parse_args(result_class=LaunchCLIOptions, args=args, ospec=options_spec)
    except SystemExit as e:
        raise ValueError from e
    return LaunchSpec(opts, args)


def get_env(opts: LaunchCLIOptions, active_child: Child) -> Dict[str, str]:
    env: Dict[str, str] = {}
    if opts.copy_env and active_child:
        env.update(active_child.foreground_environ)
    for x in opts.env:
        for k, v in parse_env(x, env):
            env[k] = v
    return env


def tab_for_window(boss: Boss, opts: LaunchCLIOptions, target_tab: Optional[Tab] = None) -> Optional[Tab]:
    if opts.type == 'tab':
        if target_tab is not None:
            tm = target_tab.tab_manager_ref() or boss.active_tab_manager
        else:
            tm = boss.active_tab_manager
        if tm:
            tab: Optional[Tab] = tm.new_tab(empty_tab=True, location=opts.location)
            if opts.tab_title and tab is not None:
                tab.set_title(opts.tab_title)
        else:
            tab = None
    elif opts.type == 'os-window':
        oswid = boss.add_os_window(wclass=opts.os_window_class, wname=opts.os_window_name, override_title=opts.os_window_title or None)
        tm = boss.os_window_map[oswid]
        tab = tm.new_tab(empty_tab=True)
        if opts.tab_title and tab is not None:
            tab.set_title(opts.tab_title)
    else:
        tab = target_tab or boss.active_tab

    return tab


watcher_modules: Dict[str, Any] = {}


def load_watch_modules(watchers: Iterable[str]) -> Optional[Watchers]:
    if not watchers:
        return None
    import runpy
    ans = Watchers()
    for path in watchers:
        path = resolve_custom_file(path)
        m = watcher_modules.get(path, None)
        if m is None:
            try:
                m = runpy.run_path(path, run_name='__kitty_watcher__')
            except Exception as err:
                import traceback
                log_error(traceback.format_exc())
                log_error(f'Failed to load watcher from {path} with error: {err}')
                watcher_modules[path] = False
                continue
            watcher_modules[path] = m
        if m is False:
            continue
        w = m.get('on_close')
        if callable(w):
            ans.on_close.append(w)
        w = m.get('on_resize')
        if callable(w):
            ans.on_resize.append(w)
        w = m.get('on_focus_change')
        if callable(w):
            ans.on_focus_change.append(w)
    return ans


class LaunchKwds(TypedDict):

    allow_remote_control: bool
    cwd_from: Optional[int]
    cwd: Optional[str]
    location: Optional[str]
    override_title: Optional[str]
    copy_colors_from: Optional[Window]
    marker: Optional[str]
    cmd: Optional[List[str]]
    overlay_for: Optional[int]
    stdin: Optional[bytes]


def apply_colors(window: Window, spec: Sequence[str]) -> None:
    from kitty.rc.set_colors import parse_colors
    colors, cursor_text_color = parse_colors(spec)
    profiles = window.screen.color_profile,
    patch_color_profiles(colors, cursor_text_color, profiles, True)


def launch(
    boss: Boss,
    opts: LaunchCLIOptions,
    args: List[str],
    target_tab: Optional[Tab] = None,
    force_target_tab: bool = False
) -> Optional[Window]:
    active = boss.active_window_for_cwd
    active_child = getattr(active, 'child', None)
    env = get_env(opts, active_child)
    kw: LaunchKwds = {
        'allow_remote_control': opts.allow_remote_control,
        'cwd_from': None,
        'cwd': None,
        'location': None,
        'override_title': opts.window_title or None,
        'copy_colors_from': None,
        'marker': opts.marker or None,
        'cmd': None,
        'overlay_for': None,
        'stdin': None
    }
    if opts.cwd:
        if opts.cwd == 'current':
            if active_child:
                kw['cwd_from'] = active_child.pid_for_cwd
        else:
            kw['cwd'] = opts.cwd
    if opts.location != 'default':
        kw['location'] = opts.location
    if opts.copy_colors and active:
        kw['copy_colors_from'] = active
    pipe_data: Dict[str, Any] = {}
    if opts.stdin_source != 'none':
        q = str(opts.stdin_source)
        if opts.stdin_add_formatting:
            if q in ('@screen', '@screen_scrollback', '@alternate', '@alternate_scrollback'):
                q = '@ansi_' + q[1:]
        if opts.stdin_add_line_wrap_markers:
            q += '_wrap'
        penv, stdin = boss.process_stdin_source(window=active, stdin=q, copy_pipe_data=pipe_data)
        if stdin:
            kw['stdin'] = stdin
            if penv:
                env.update(penv)

    cmd = args or None
    if opts.copy_cmdline and active_child:
        cmd = active_child.foreground_cmdline
    if cmd:
        final_cmd: List[str] = []
        for x in cmd:
            if active and not opts.copy_cmdline:
                if x == '@selection':
                    s = boss.data_for_at(which=x, window=active)
                    if s:
                        x = s
                elif x == '@active-kitty-window-id':
                    x = str(active.id)
                elif x == '@input-line-number':
                    if 'input_line_number' in pipe_data:
                        x = str(pipe_data['input_line_number'])
                elif x == '@line-count':
                    if 'lines' in pipe_data:
                        x = str(pipe_data['lines'])
                elif x in ('@cursor-x', '@cursor-y', '@scrolled-by'):
                    if active is not None:
                        screen = active.screen
                        if x == '@scrolled-by':
                            x = str(screen.scrolled_by)
                        elif x == '@cursor-x':
                            x = str(screen.cursor.x + 1)
                        elif x == '@cursor-y':
                            x = str(screen.cursor.y + 1)
            final_cmd.append(x)
        exe = find_exe(final_cmd[0])
        if not exe:
            xenv = read_shell_environment(get_options())
            if 'PATH' in xenv:
                import shutil
                exe = shutil.which(final_cmd[0], path=xenv['PATH'])
        if exe:
            final_cmd[0] = exe
        kw['cmd'] = final_cmd
    if opts.type == 'overlay' and active:
        kw['overlay_for'] = active.id
    if opts.type == 'background':
        cmd = kw['cmd']
        if not cmd:
            raise ValueError('The cmd to run must be specified when running a background process')
        boss.run_background_process(cmd, cwd=kw['cwd'], cwd_from=kw['cwd_from'], env=env or None, stdin=kw['stdin'])
    elif opts.type in ('clipboard', 'primary'):
        stdin = kw.get('stdin')
        if stdin is not None:
            if opts.type == 'clipboard':
                set_clipboard_string(stdin)
            else:
                set_primary_selection(stdin)
    else:
        if force_target_tab:
            tab = target_tab
        else:
            tab = tab_for_window(boss, opts, target_tab)
        if tab is not None:
            watchers = load_watch_modules(opts.watcher)
            new_window: Window = tab.new_window(env=env or None, watchers=watchers or None, **kw)
            if opts.color:
                apply_colors(new_window, opts.color)
            if opts.keep_focus and active:
                boss.set_active_window(active, switch_os_window_if_needed=True)
            return new_window
    return None