import os
import shutil
import subprocess
import time

from whisper_app import app, config


def _pynput_type(text):
    from pynput.keyboard import Controller as KeyboardController
    KeyboardController().type(text)


def _wl_paste():
    """Read current clipboard contents, returns None on failure."""
    try:
        result = subprocess.run(
            ["wl-paste", "--no-newline"],
            capture_output=True, timeout=2,
        )
        if result.returncode == 0:
            return result.stdout
    except (subprocess.TimeoutExpired, FileNotFoundError):
        pass
    return None


def _wl_copy_bytes(data):
    """Restore clipboard from raw bytes."""
    try:
        subprocess.run(
            ["wl-copy"],
            input=data, check=False, timeout=2,
        )
    except (subprocess.TimeoutExpired, FileNotFoundError):
        pass


def _paste_via_ydotool():
    """Simulate Ctrl+V using ydotool (kernel-level, works on all compositors)."""
    subprocess.run(["ydotool", "key", "29:1", "47:1", "47:0", "29:0"], check=False)


def _paste_via_wtype():
    """Simulate Ctrl+V using wtype (native Wayland, wlroots only)."""
    subprocess.run(["wtype", "-M", "ctrl", "-P", "v", "-p", "v", "-m", "ctrl"],
                   check=False)


def _paste_via_xdotool():
    """Simulate Ctrl+V using xdotool (XWayland fallback)."""
    subprocess.run(["xdotool", "key", "ctrl+v"], check=False)


def _pick_paste_cmd():
    """Select best available paste tool for the current Wayland session."""
    if shutil.which("ydotool"):
        return _paste_via_ydotool
    if shutil.which("wtype"):
        return _paste_via_wtype
    return _paste_via_xdotool


def type_text(text):
    """Type text into the active window, cross-platform."""
    if os.name == "nt":
        _pynput_type(text)
        return
    session = os.environ.get("XDG_SESSION_TYPE", "")
    if session == "wayland" and shutil.which("wl-copy"):
        delay = config.config.get("paste_delay_ms", 300) / 1000.0
        old_clipboard = _wl_paste()
        subprocess.run(["wl-copy", "--", text], check=False)
        time.sleep(0.05)
        paste_fn = _pick_paste_cmd()
        app.log(f"typer: using {paste_fn.__name__}, session={session}")
        paste_fn()
        time.sleep(delay)
        if old_clipboard is not None:
            _wl_copy_bytes(old_clipboard)
    elif shutil.which("xdotool"):
        subprocess.run(["xdotool", "type", "--clearmodifiers", "--", text], check=False)
    else:
        _pynput_type(text)