"""Input handling, completers, and prompt session for the CLI."""

import asyncio import os import re import time from collections.abc import Callable from pathlib import Path

from prompt_toolkit import PromptSession from prompt_toolkit.completion import ( Completer, Completion, PathCompleter, merge_completers, ) from prompt_toolkit.document import Document from prompt_toolkit.enums import EditingMode from prompt_toolkit.formatted_text import HTML from prompt_toolkit.key_binding import KeyBindings

from .config import COLORS, COMMANDS, SessionState, console from .image_utils import ImageData, get_clipboard_image

Regex patterns for context-aware completion

AT_MENTION_RE = re.compile(r"@(?P<path>(?:[^\s@]|(?<=\)\s))$") SLASH_COMMAND_RE = re.compile(r"^/(?P<command>[a-z])$")

EXIT_CONFIRM_WINDOW = 3.0

class ImageTracker: """Track pasted images in the current conversation."""

def __init__(self) -> None:
    self.images: list[ImageData] = []
    self.next_id = 1

def add_image(self, image_data: ImageData) -> str:
    """Add an image and return its placeholder text.

    Args:
        image_data: The image data to track

    Returns:
        Placeholder string like "[image 1]"
    """
    placeholder = f"[image {self.next_id}]"
    image_data.placeholder = placeholder
    self.images.append(image_data)
    self.next_id += 1
    return placeholder

def get_images(self) -> list[ImageData]:
    """Get all tracked images."""
    return self.images.copy()

def clear(self) -> None:
    """Clear all tracked images and reset counter."""
    self.images.clear()
    self.next_id = 1

class FilePathCompleter(Completer): """Activate filesystem completion only when cursor is after '@'."""

def __init__(self) -> None:
    self.path_completer = PathCompleter(
        expanduser=True,
        min_input_len=0,
        only_directories=False,
    )

def get_completions(self, document, complete_event):
    """Get file path completions when @ is detected."""
    text = document.text_before_cursor

    # Use regex to detect @path pattern at end of line
    m = AT_MENTION_RE.search(text)
    if not m:
        return  # Not in an @path context

    path_fragment = m.group("path")

    # Unescape the path for PathCompleter (it doesn't understand escape sequences)
    unescaped_fragment = path_fragment.replace("\\ ", " ")

    # Strip trailing backslash if present (user is in the process of typing an escape)
    unescaped_fragment = unescaped_fragment.removesuffix("\\")

    # Create temporary document for the unescaped path fragment
    temp_doc = Document(text=unescaped_fragment, cursor_position=len(unescaped_fragment))

    # Get completions from PathCompleter and use its start_position
    # PathCompleter returns suffix text with start_position=0 (insert at cursor)
    for comp in self.path_completer.get_completions(temp_doc, complete_event):
        # Add trailing / for directories so users can continue navigating
        completed_path = Path(unescaped_fragment + comp.text).expanduser()
        # Re-escape spaces in the completion text for the command line
        completion_text = comp.text.replace(" ", "\\ ")
        if completed_path.is_dir() and not completion_text.endswith("/"):
            completion_text += "/"

        yield Completion(
            text=completion_text,
            start_position=comp.start_position,  # Use PathCompleter's position (usually 0)
            display=comp.display,
            display_meta=comp.display_meta,
        )

class CommandCompleter(Completer): """Activate command completion only when line starts with '/'."""

def get_completions(self, document, _complete_event):
    """Get command completions when / is at the start."""
    text = document.text_before_cursor

    # Use regex to detect /command pattern at start of line
    m = SLASH_COMMAND_RE.match(text)
    if not m:
        return  # Not in a /command context

    command_fragment = m.group("command")

    # Match commands that start with the fragment (case-insensitive)
    for cmd_name, cmd_desc in COMMANDS.items():
        if cmd_name.startswith(command_fragment.lower()):
            yield Completion(
                text=cmd_name,
                start_position=-len(command_fragment),  # Fixed position for original document
                display=cmd_name,
                display_meta=cmd_desc,
            )

def parse_file_mentions(text: str) -> tuple[str, list[Path]]: """Extract @file mentions and return cleaned text with resolved file paths.""" pattern = r"@((?:[^\s@]|(?<=\)\s)+)" # Match @filename, allowing escaped spaces matches = re.findall(pattern, text)

files = []
for match in matches:
    # Remove escape characters
    clean_path = match.replace("\\ ", " ")
    path = Path(clean_path).expanduser()

    # Try to resolve relative to cwd
    if not path.is_absolute():
        path = Path.cwd() / path

    try:
        path = path.resolve()
        if path.exists() and path.is_file():
            files.append(path)
        else:
            console.print(f"[yellow]Warning: File not found: {match}[/yellow]")
    except Exception as e:
        console.print(f"[yellow]Warning: Invalid path {match}: {e}[/yellow]")

return text, files

def parse_image_placeholders(text: str) -> tuple[str, int]: """Count image placeholders in text.

Args:
    text: Input text potentially containing [image] or [image N] placeholders

Returns:
    Tuple of (text, count) where count is the number of image placeholders found
"""
# Match [image] or [image N] patterns
pattern = r"\[image(?:\s+\d+)?\]"
matches = re.findall(pattern, text, re.IGNORECASE)
return text, len(matches)

def get_bottom_toolbar( session_state: SessionState, session_ref: dict ) -> Callable[[], list[tuple[str, str]]]: """Return toolbar function that shows auto-approve status and BASH MODE."""

def toolbar() -> list[tuple[str, str]]:
    parts = []

    # Check if we're in BASH mode (input starts with !)
    try:
        session = session_ref.get("session")
        if session:
            current_text = session.default_buffer.text
            if current_text.startswith("!"):
                parts.append(("bg:#ff1493 fg:#ffffff bold", " BASH MODE "))
                parts.append(("", " | "))
    except (AttributeError, TypeError):
        # Silently ignore - toolbar is non-critical and called frequently
        pass

    # Base status message
    if session_state.auto_approve:
        base_msg = "auto-accept ON (CTRL+T to toggle)"
        base_class = "class:toolbar-green"
    else:
        base_msg = "manual accept (CTRL+T to toggle)"
        base_class = "class:toolbar-orange"

    parts.append((base_class, base_msg))

    # Show exit confirmation hint if active
    hint_until = session_state.exit_hint_until
    if hint_until is not None:
        now = time.monotonic()
        if now < hint_until:
            parts.append(("", " | "))
            parts.append(("class:toolbar-exit", " Ctrl+C again to exit "))
        else:
            session_state.exit_hint_until = None

    return parts

return toolbar

def create_prompt_session( _assistant_id: str, session_state: SessionState, image_tracker: ImageTracker | None = None ) -> PromptSession: """Create a configured PromptSession with all features.""" # Set default editor if not already set if "EDITOR" not in os.environ: os.environ["EDITOR"] = "nano"

# Create key bindings
kb = KeyBindings()

@kb.add("c-c")
def _(event) -> None:
    """Require double Ctrl+C within a short window to exit."""
    app = event.app
    now = time.monotonic()

    if session_state.exit_hint_until is not None and now < session_state.exit_hint_until:
        handle = session_state.exit_hint_handle
        if handle:
            handle.cancel()
            session_state.exit_hint_handle = None
        session_state.exit_hint_until = None
        app.invalidate()
        app.exit(exception=KeyboardInterrupt())
        return

    session_state.exit_hint_until = now + EXIT_CONFIRM_WINDOW

    handle = session_state.exit_hint_handle
    if handle:
        handle.cancel()

    loop = asyncio.get_running_loop()
    app_ref = app

    def clear_hint() -> None:
        if (
            session_state.exit_hint_until is not None
            and time.monotonic() >= session_state.exit_hint_until
        ):
            session_state.exit_hint_until = None
            session_state.exit_hint_handle = None
            app_ref.invalidate()

    session_state.exit_hint_handle = loop.call_later(EXIT_CONFIRM_WINDOW, clear_hint)

    app.invalidate()

# Bind Ctrl+T to toggle auto-approve
@kb.add("c-t")
def _(event) -> None:
    """Toggle auto-approve mode."""
    session_state.toggle_auto_approve()
    # Force UI refresh to update toolbar
    event.app.invalidate()

# Custom paste handler to detect images
if image_tracker:
    from prompt_toolkit.keys import Keys

    def _handle_paste_with_image_check(event, pasted_text: str = "") -> None:
        """Check clipboard for image, otherwise insert pasted text."""
        # Try to get an image from clipboard
        clipboard_image = get_clipboard_image()

        if clipboard_image:
            # Found an image! Add it to tracker and insert placeholder
            placeholder = image_tracker.add_image(clipboard_image)
            # Insert placeholder (no confirmation message)
            event.current_buffer.insert_text(placeholder)
        elif pasted_text:
            # No image, insert the pasted text
            event.current_buffer.insert_text(pasted_text)
        else:
            # Fallback: try to get text from prompt_toolkit clipboard
            clipboard_data = event.app.clipboard.get_data()
            if clipboard_data and clipboard_data.text:
                event.current_buffer.insert_text(clipboard_data.text)

    @kb.add(Keys.BracketedPaste)
    def _(event) -> None:
        """Handle bracketed paste (Cmd+V on macOS) - check for images first."""
        # Bracketed paste provides the pasted text in event.data
        pasted_text = event.data if hasattr(event, "data") else ""
        _handle_paste_with_image_check(event, pasted_text)

    @kb.add("c-v")
    def _(event) -> None:
        """Handle Ctrl+V paste - check for images first."""
        _handle_paste_with_image_check(event)

# Bind regular Enter to submit (intuitive behavior)
@kb.add("enter")
def _(event) -> None:
    """Enter submits the input, unless completion menu is active."""
    buffer = event.current_buffer

    # If completion menu is showing, apply the current completion
    if buffer.complete_state:
        # Get the current completion (the highlighted one)
        current_completion = buffer.complete_state.current_completion

        # If no completion is selected (user hasn't navigated), select and apply the first one
        if not current_completion and buffer.complete_state.completions:
            # Move to the first completion
            buffer.complete_next()
            # Now apply it
            buffer.apply_completion(buffer.complete_state.current_completion)
        elif current_completion:
            # Apply the already-selected completion
            buffer.apply_completion(current_completion)
        else:
            # No completions available, close menu
            buffer.complete_state = None
    # Don't submit if buffer is empty or only whitespace
    elif buffer.text.strip():
        # Normal submit
        buffer.validate_and_handle()
        # If empty, do nothing (don't submit)

# Alt+Enter for newlines (press ESC then Enter, or Option+Enter on Mac)
@kb.add("escape", "enter")
def _(event) -> None:
    """Alt+Enter inserts a newline for multi-line input."""
    event.current_buffer.insert_text("\n")

# Ctrl+E to open in external editor
@kb.add("c-e")
def _(event) -> None:
    """Open the current input in an external editor (nano by default)."""
    event.current_buffer.open_in_editor()

# Backspace handler to retrigger completions and delete image tags as units
@kb.add("backspace")
def _(event) -> None:
    """Handle backspace: delete image tags as single unit, retrigger completion."""
    buffer = event.current_buffer
    text_before = buffer.document.text_before_cursor

    # Check if cursor is right after an image tag like [image 1] or [image 12]
    image_tag_pattern = r"\[image \d+\]$"
    match = re.search(image_tag_pattern, text_before)

    if match and image_tracker:
        # Delete the entire tag
        tag_length = len(match.group(0))
        buffer.delete_before_cursor(count=tag_length)

        # Remove the image from tracker and reset counter
        tag_text = match.group(0)
        image_num_match = re.search(r"\d+", tag_text)
        if image_num_match:
            image_num = int(image_num_match.group(0))
            # Remove image at index (1-based to 0-based)
            if 0 < image_num <= len(image_tracker.images):
                image_tracker.images.pop(image_num - 1)
                # Reset counter to next available number
                image_tracker.next_id = len(image_tracker.images) + 1
    else:
        # Normal backspace
        buffer.delete_before_cursor(count=1)

    # Check if we're in a completion context (@ or /)
    text = buffer.document.text_before_cursor
    if AT_MENTION_RE.search(text) or SLASH_COMMAND_RE.match(text):
        # Retrigger completion
        buffer.start_completion(select_first=False)

from prompt_toolkit.styles import Style

# Define styles for the toolbar with full-width background colors
toolbar_style = Style.from_dict(
    {
        "bottom-toolbar": "noreverse",  # Disable default reverse video
        "toolbar-green": "bg:#10b981 #000000",  # Green for auto-accept ON
        "toolbar-orange": "bg:#f59e0b #000000",  # Orange for manual accept
        "toolbar-exit": "bg:#2563eb #ffffff",  # Blue for exit hint
    }
)

# Create session reference dict for toolbar to access session
session_ref = {}

# Create the session
session = PromptSession(
    message=HTML(f'<style fg="{COLORS["user"]}">></style> '),
    multiline=True,  # Keep multiline support but Enter submits
    key_bindings=kb,
    completer=merge_completers([CommandCompleter(), FilePathCompleter()]),
    editing_mode=EditingMode.EMACS,
    complete_while_typing=True,  # Show completions as you type
    complete_in_thread=True,  # Async completion prevents menu freezing
    mouse_support=False,
    enable_open_in_editor=True,  # Allow Ctrl+X Ctrl+E to open external editor
    bottom_toolbar=get_bottom_toolbar(
        session_state, session_ref
    ),  # Persistent status bar at bottom
    style=toolbar_style,  # Apply toolbar styling
    reserve_space_for_menu=7,  # Reserve space for completion menu to show 5-6 results
)

# Store session reference for toolbar to access
session_ref["session"] = session

return session