Source code for continuity.utils.pager

"""
Pager utilities for enhanced content viewing.
Provides smart pager detection and beautiful content formatting.
"""

import os
import shutil
import subprocess
import tempfile

from rich.console import Console

console = Console()




def detect_pager() -> str:
    """Detect the best available pager.

    Returns:
        Pager command string
    """
    # Check PAGER environment variable first
    pager = os.environ.get("PAGER")
    if pager and shutil.which(pager.split()[0]):
        return pager

    # Check for enhanced pagers
    enhanced_pagers = ["bat", "batcat", "less", "more"]

    for pager in enhanced_pagers:
        if shutil.which(pager):
            # Add useful flags for each pager
            if pager in ["bat", "batcat"]:
                return f"{pager} --style=header,grid --theme=ansi"
            elif pager == "less":
                return "less -R"  # -R for ANSI color support
            else:
                return pager

    # Fallback to more (should be available on most systems)
    return "more"





def format_message_content(
    message, show_metadata: bool = True, user_context=None
) -> str:
    """Format message content for display.

    Args:
        message: Message object with content, metadata
        show_metadata: Whether to include metadata header
        user_context: UserContext for nickname mapping (optional)

    Returns:
        Formatted content string
    """
    content_parts = []

    if show_metadata:
        # Apply nickname mapping if user_context is provided
        sender_name = message.sender
        recipient_name = message.recipient
        if user_context:
            sender_name = user_context.get_display_name(message.sender)
            recipient_name = user_context.get_display_name(message.recipient)

        # Create metadata header
        metadata_lines = [
            f"From: {sender_name}",
            f"To: {recipient_name}",
            f"Date: {message.timestamp.strftime('%Y-%m-%d %H:%M:%S')}",
            f"Title: {message.title or 'Untitled'}",
            f"Status: {'Read' if message.read else 'Unread'}",
            f"ID: {message.id}",
        ]

        # Use a simple text-based header for better pager compatibility
        header = "=" * 60 + "\n"
        header += "\n".join(metadata_lines)
        header += "\n" + "=" * 60 + "\n\n"
        content_parts.append(header)

    # Add the message content
    content_parts.append(message.content)

    # Add footer if metadata is shown
    if show_metadata:
        footer = "\n\n" + "-" * 60 + "\n"
        footer += "Navigation: q=quit, space=next page, b=back, /=search"
        content_parts.append(footer)

    return "".join(content_parts)





def format_thread_content(thread_name: str, posts: list) -> str:
    """Format thread content for display.

    Args:
        thread_name: Name of the thread
        posts: List of post objects

    Returns:
        Formatted thread content
    """
    content_parts = []

    # Thread header
    header = "=" * 60 + "\n"
    header += f"Thread: {thread_name}\n"
    header += f"Posts: {len(posts)}\n"
    header += "=" * 60 + "\n\n"
    content_parts.append(header)

    # Format each post
    for i, post in enumerate(posts, 1):
        post_header = f"--- Post {i} ---\n"
        post_header += f"Author: {post.get('author', 'Unknown')}\n"
        post_header += f"Date: {post.get('timestamp', 'Unknown')}\n"
        post_header += "-" * 40 + "\n\n"

        content_parts.append(post_header)
        content_parts.append(post["content"])
        content_parts.append("\n\n")

    # Footer
    footer = "=" * 60 + "\n"
    footer += "End of thread\n"
    footer += "Navigation: q=quit, space=next page, b=back, /=search"
    content_parts.append(footer)

    return "".join(content_parts)





def view_with_pager(content: str, title: str = "Content") -> bool:
    """Display content using system pager.

    Args:
        content: Content to display
        title: Title for the content (used in temp filename)

    Returns:
        True if content was displayed successfully
    """
    pager_cmd = detect_pager()

    # Create temporary file with the content
    try:
        with tempfile.NamedTemporaryFile(
            mode="w",
            suffix=".txt",
            prefix=f'continuity-{title.lower().replace(" ", "-")}-',
            delete=False,
            encoding="utf-8",
        ) as tmp_file:
            tmp_file.write(content)
            tmp_path = tmp_file.name

        # Run pager command
        try:
            pager_parts = pager_cmd.split()
            result = subprocess.run(pager_parts + [tmp_path], check=True)
            return True

        except subprocess.CalledProcessError:
            # Fallback to console print if pager fails
            console.print("[yellow]Pager failed, displaying in console:[/yellow]")
            console.print(content)
            return True

        except FileNotFoundError:
            # Pager not found, fallback to console
            console.print(
                f"[yellow]Pager '{pager_cmd}' not found, displaying in console:[/yellow]"
            )
            console.print(content)
            return True

    except Exception as e:
        console.print(f"[red]Error displaying content:[/red] {e}")
        return False

    finally:
        # Clean up temporary file
        try:
            if "tmp_path" in locals():
                os.unlink(tmp_path)
        except OSError:
            pass





def preview_content(content: str, max_lines: int = 10) -> str:
    """Create a preview of content for quick display.

    Args:
        content: Full content
        max_lines: Maximum lines to show in preview

    Returns:
        Preview content with ellipsis if truncated
    """
    lines = content.split("\n")

    if len(lines) <= max_lines:
        return content

    preview_lines = lines[:max_lines]
    preview_lines.append(f"... ({len(lines) - max_lines} more lines)")

    return "\n".join(preview_lines)