import click
import asyncio
import os
import sys
from rich.progress import Progress, SpinnerColumn, MofNCompleteColumn
from datetime import datetime, timedelta

from src.utils.mail_utils.helpers import ensure_directory_exists
from src.utils.calendar_utils import save_events_to_vdir, save_events_to_file
from src.services.microsoft_graph.calendar import (
    fetch_calendar_events,
    sync_local_calendar_changes,
    get_last_sync_time,
    detect_deleted_events,
)
from src.services.microsoft_graph.mail import (
    fetch_mail_async,
    archive_mail_async,
    delete_mail_async,
    synchronize_maildir_async,
)
from src.services.microsoft_graph.auth import get_access_token


# Function to create Maildir structure
def create_maildir_structure(base_path):
    """
    Create the standard Maildir directory structure.

    Args:
        base_path (str): Base path for the Maildir.

    Returns:
        None
    """
    ensure_directory_exists(os.path.join(base_path, "cur"))
    ensure_directory_exists(os.path.join(base_path, "new"))
    ensure_directory_exists(os.path.join(base_path, "tmp"))
    ensure_directory_exists(os.path.join(base_path, ".Archives"))
    ensure_directory_exists(os.path.join(base_path, ".Trash", "cur"))


async def fetch_calendar_async(
    headers,
    progress,
    task_id,
    dry_run,
    vdir_path,
    ics_path,
    org_name,
    days_back,
    days_forward,
    continue_iteration,
):
    """
    Fetch calendar events and save them in the appropriate format.

    Args:
        headers: Authentication headers for Microsoft Graph API
        progress: Progress instance for updating progress bars
        task_id: ID of the task in the progress bar

    Returns:
        List of event dictionaries

    Raises:
        Exception: If there's an error fetching or saving events
    """
    try:
        # Use the utility function to fetch calendar events
        progress.console.print(
            "[cyan]Fetching events from Microsoft Graph API...[/cyan]"
        )
        events, total_events = await fetch_calendar_events(
            headers=headers, days_back=days_back, days_forward=days_forward
        )

        progress.console.print(
            f"[cyan]Got {len(events)} events from API (reported total: {total_events})[/cyan]"
        )

        # Update progress bar with total events
        progress.update(task_id, total=total_events)

        # Save events to appropriate format
        if not dry_run:
            if vdir_path:
                # Create org-specific directory within vdir path
                org_vdir_path = os.path.join(vdir_path, org_name)
                progress.console.print(
                    f"[cyan]Saving events to vdir: {org_vdir_path}[/cyan]"
                )
                save_events_to_vdir(events, org_vdir_path, progress, task_id, dry_run)
                progress.console.print(
                    f"[green]Finished saving events to vdir: {org_vdir_path}[/green]"
                )
            elif ics_path:
                # Save to a single ICS file in the output_ics directory
                progress.console.print(
                    f"[cyan]Saving events to ICS file: {ics_path}/events_latest.ics[/cyan]"
                )
                save_events_to_file(
                    events, f"{ics_path}/events_latest.ics", progress, task_id, dry_run
                )
                progress.console.print(
                    f"[green]Finished saving events to ICS file[/green]"
                )
            else:
                # No destination specified
                progress.console.print(
                    "[yellow]Warning: No destination path (--vdir or --icsfile) specified for calendar events.[/yellow]"
                )
        else:
            progress.console.print(
                f"[DRY-RUN] Would save {len(events)} events to {
                    'vdir format' if vdir_path else 'single ICS file'
                }"
            )
            progress.update(task_id, advance=len(events))

        # Interactive mode: Ask if the user wants to continue with the next date range
        if continue_iteration:
            # Move to the next date range
            next_start_date = datetime.now() - timedelta(days=days_back)
            next_end_date = next_start_date + timedelta(days=days_forward)

            progress.console.print(
                f"\nCurrent date range: {next_start_date.strftime('%Y-%m-%d')} to {
                    next_end_date.strftime('%Y-%m-%d')
                }"
            )

            user_response = (
                click.prompt("\nContinue to iterate? [y/N]", default="N")
                .strip()
                .lower()
            )

            while user_response == "y":
                progress.console.print(
                    f"\nFetching events for {next_start_date.strftime('%Y-%m-%d')} to {
                        next_end_date.strftime('%Y-%m-%d')
                    }..."
                )

                # Reset the progress bar for the new fetch
                progress.update(task_id, completed=0, total=0)

                # Fetch events for the next date range
                next_events, next_total_events = await fetch_calendar_events(
                    headers=headers,
                    days_back=0,
                    days_forward=days_forward,
                    start_date=next_start_date,
                    end_date=next_end_date,
                )

                # Update progress bar with total events
                progress.update(task_id, total=next_total_events)

                if not dry_run:
                    if vdir_path:
                        save_events_to_vdir(
                            next_events, org_vdir_path, progress, task_id, dry_run
                        )
                    else:
                        save_events_to_file(
                            next_events,
                            f"output_ics/outlook_events_{next_start_date.strftime('%Y%m%d')}.ics",
                            progress,
                            task_id,
                            dry_run,
                        )
                else:
                    progress.console.print(
                        f"[DRY-RUN] Would save {len(next_events)} events to {
                            'vdir format'
                            if vdir_path
                            else 'output_ics/outlook_events_'
                            + next_start_date.strftime('%Y%m%d')
                            + '.ics'
                        }"
                    )
                    progress.update(task_id, advance=len(next_events))

                # Calculate the next date range
                next_start_date = next_end_date
                next_end_date = next_start_date + timedelta(days=days_forward)

                progress.console.print(
                    f"\nNext date range would be: {
                        next_start_date.strftime('%Y-%m-%d')
                    } to {next_end_date.strftime('%Y-%m-%d')}"
                )
                user_response = (
                    click.prompt("\nContinue to iterate? [y/N]", default="N")
                    .strip()
                    .lower()
                )

        return events
    except Exception as e:
        progress.console.print(
            f"[red]Error fetching or saving calendar events: {str(e)}[/red]"
        )
        import traceback

        progress.console.print(f"[red]{traceback.format_exc()}[/red]")
        progress.update(task_id, completed=True)
        return []


async def _sync_outlook_data(
    dry_run,
    vdir,
    icsfile,
    org,
    days_back,
    days_forward,
    continue_iteration,
    download_attachments,
    two_way_calendar,
):
    """Synchronize data from external sources."""

    # Expand the user home directory in vdir path
    vdir = os.path.expanduser(vdir)

    # Save emails to Maildir
    maildir_path = os.getenv("MAILDIR_PATH", os.path.expanduser("~/Mail")) + f"/{org}"
    attachments_dir = os.path.join(maildir_path, "attachments")
    ensure_directory_exists(attachments_dir)
    create_maildir_structure(maildir_path)

    # Define scopes for Microsoft Graph API
    scopes = [
        "https://graph.microsoft.com/Calendars.Read",
        "https://graph.microsoft.com/Mail.ReadWrite",
    ]

    # Authenticate and get access token
    access_token, headers = get_access_token(scopes)

    # Set up the progress bars
    progress = Progress(
        SpinnerColumn(), MofNCompleteColumn(), *Progress.get_default_columns()
    )

    with progress:
        task_fetch = progress.add_task("[green]Syncing Inbox...", total=0)
        task_calendar = progress.add_task("[cyan]Fetching calendar...", total=0)
        task_local_calendar = progress.add_task(
            "[magenta]Syncing local calendar...", total=0
        )
        task_read = progress.add_task("[blue]Marking as read...", total=0)
        task_archive = progress.add_task("[yellow]Archiving mail...", total=0)
        task_delete = progress.add_task("[red]Deleting mail...", total=0)

        # Stage 1: Synchronize local changes (read, archive, delete, calendar) to the server
        progress.console.print(
            "[bold cyan]Step 1: Syncing local changes to server...[/bold cyan]"
        )

        # Handle calendar sync first (if vdir is specified and two-way sync is enabled)
        calendar_sync_results = (0, 0)
        if vdir and two_way_calendar:
            org_vdir_path = os.path.join(os.path.expanduser(vdir), org)
            progress.console.print(
                f"[magenta]Checking for local calendar changes in {org_vdir_path}...[/magenta]"
            )
            calendar_sync_results = await sync_local_calendar_changes(
                headers, org_vdir_path, progress, task_local_calendar, dry_run
            )

        # Handle mail changes in parallel
        await asyncio.gather(
            synchronize_maildir_async(
                maildir_path, headers, progress, task_read, dry_run
            ),
            archive_mail_async(maildir_path, headers, progress, task_archive, dry_run),
            delete_mail_async(maildir_path, headers, progress, task_delete, dry_run),
        )
        progress.console.print("[bold green]Step 1: Local changes synced.[/bold green]")

        # Report calendar sync results
        created, deleted = calendar_sync_results
        if two_way_calendar and (created > 0 or deleted > 0):
            progress.console.print(
                f"[magenta]📅 Two-way calendar sync: {created} events created, {deleted} events deleted[/magenta]"
            )
        elif two_way_calendar:
            progress.console.print(
                "[magenta]📅 Two-way calendar sync: No local changes detected[/magenta]"
            )

        # Stage 2: Fetch new data from the server
        progress.console.print(
            "\n[bold cyan]Step 2: Fetching new data from server...[/bold cyan]"
        )
        await asyncio.gather(
            fetch_mail_async(
                maildir_path,
                attachments_dir,
                headers,
                progress,
                task_fetch,
                dry_run,
                download_attachments,
            ),
            fetch_calendar_async(
                headers,
                progress,
                task_calendar,
                dry_run,
                vdir,
                icsfile,
                org,
                days_back,
                days_forward,
                continue_iteration,
            ),
        )
        progress.console.print("[bold green]Step 2: New data fetched.[/bold green]")
    click.echo("Sync complete.")


@click.command()
@click.option(
    "--dry-run",
    is_flag=True,
    help="Run in dry-run mode without making changes.",
    default=False,
)
@click.option(
    "--vdir",
    help="Output calendar events in vdir format to the specified directory (each event in its own file)",
    default="~/Calendar",
)
@click.option(
    "--icsfile", help="Output calendar events into this ics file path.", default=None
)
@click.option(
    "--org",
    help="Specify the organization name for the subfolder to store emails and calendar events",
    default="corteva",
)
@click.option(
    "--days-back",
    type=int,
    help="Number of days to look back for calendar events",
    default=1,
)
@click.option(
    "--days-forward",
    type=int,
    help="Number of days to look forward for calendar events",
    default=30,
)
@click.option(
    "--continue-iteration",
    is_flag=True,
    help="Enable interactive mode to continue fetching more date ranges",
    default=False,
)
@click.option(
    "--download-attachments",
    is_flag=True,
    help="Download email attachments",
    default=False,
)
@click.option(
    "--two-way-calendar",
    is_flag=True,
    help="Enable two-way calendar sync (sync local changes to server)",
    default=False,
)
@click.option(
    "--daemon",
    is_flag=True,
    help="Run in daemon mode.",
    default=False,
)
def sync(
    dry_run,
    vdir,
    icsfile,
    org,
    days_back,
    days_forward,
    continue_iteration,
    download_attachments,
    two_way_calendar,
    daemon,
):
    if daemon:
        asyncio.run(
            daemon_mode(
                dry_run,
                vdir,
                icsfile,
                org,
                days_back,
                days_forward,
                continue_iteration,
                download_attachments,
                two_way_calendar,
            )
        )
    else:
        asyncio.run(
            _sync_outlook_data(
                dry_run,
                vdir,
                icsfile,
                org,
                days_back,
                days_forward,
                continue_iteration,
                download_attachments,
                two_way_calendar,
            )
        )


def check_calendar_changes(vdir_path, org):
    """
    Check if there are local calendar changes that need syncing.

    Args:
        vdir_path (str): Base vdir path
        org (str): Organization name

    Returns:
        tuple: (has_changes, change_description)
    """
    if not vdir_path:
        return False, "No vdir path configured"

    org_vdir_path = os.path.join(os.path.expanduser(vdir_path), org)

    if not os.path.exists(org_vdir_path):
        return False, "Calendar directory does not exist"

    try:
        # Get last sync time
        last_sync_time = get_last_sync_time(org_vdir_path)

        # Check if vdir directory has been modified since last sync
        vdir_mtime = os.path.getmtime(org_vdir_path)

        if vdir_mtime > last_sync_time:
            # Check for specific types of changes
            deleted_events = detect_deleted_events(org_vdir_path)

            # Count .ics files to detect new events
            import glob

            ics_files = glob.glob(os.path.join(org_vdir_path, "*.ics"))

            # Load previous state to compare
            state_file = os.path.join(org_vdir_path, ".sync_state.json")
            previous_state = {}
            if os.path.exists(state_file):
                try:
                    import json

                    with open(state_file, "r") as f:
                        previous_state = json.load(f)
                except Exception:
                    pass

            new_event_count = len(ics_files) - len(previous_state) + len(deleted_events)

            if deleted_events or new_event_count > 0:
                changes = []
                if new_event_count > 0:
                    changes.append(f"{new_event_count} new events")
                if deleted_events:
                    changes.append(f"{len(deleted_events)} deleted events")

                return True, ", ".join(changes)
            else:
                return True, "directory modified"

        return False, "no changes detected"

    except Exception as e:
        return False, f"error checking calendar: {str(e)}"


async def daemon_mode(
    dry_run,
    vdir,
    icsfile,
    org,
    days_back,
    days_forward,
    continue_iteration,
    download_attachments,
    two_way_calendar,
):
    """
    Run the script in daemon mode, periodically syncing emails and calendar.
    """
    from src.services.microsoft_graph.mail import get_inbox_count_async
    from rich.console import Console
    from rich.live import Live
    from rich.panel import Panel
    from rich.text import Text
    from datetime import datetime
    import time

    console = Console()
    sync_interval = 300  # 5 minutes
    check_interval = 10  # 10 seconds
    last_sync_time = time.time() - sync_interval  # Force initial sync

    def create_status_display(status_text, status_color="cyan"):
        """Create a status panel for daemon mode."""
        timestamp = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
        content = Text()
        content.append(f"[{timestamp}] ", style="dim")
        content.append(status_text, style=status_color)

        return Panel(
            content,
            title="📧 Email & Calendar Sync Daemon",
            border_style="blue",
            padding=(0, 1),
        )

    # Initial display
    console.print(create_status_display("Starting daemon mode...", "green"))

    while True:
        if time.time() - last_sync_time >= sync_interval:
            # Show full sync status
            console.clear()
            console.print(create_status_display("Performing full sync...", "green"))

            # Perform a full sync
            await _sync_outlook_data(
                dry_run,
                vdir,
                icsfile,
                org,
                days_back,
                days_forward,
                continue_iteration,
                download_attachments,
                two_way_calendar,
            )
            last_sync_time = time.time()

            # Show completion
            console.print(create_status_display("Full sync completed ✅", "green"))
        else:
            # Show checking status
            console.clear()
            console.print(create_status_display("Checking for changes...", "cyan"))

            try:
                # Authenticate and get access token for mail check
                scopes = ["https://graph.microsoft.com/Mail.Read"]
                access_token, headers = get_access_token(scopes)
                remote_message_count = await get_inbox_count_async(headers)
                maildir_path = os.path.expanduser(f"~/Mail/{org}")

                # Count local messages
                new_dir = os.path.join(maildir_path, "new")
                cur_dir = os.path.join(maildir_path, "cur")
                local_message_count = 0

                if os.path.exists(new_dir):
                    local_message_count += len(
                        [f for f in os.listdir(new_dir) if ".eml" in f]
                    )
                if os.path.exists(cur_dir):
                    local_message_count += len(
                        [f for f in os.listdir(cur_dir) if ".eml" in f]
                    )

                mail_changes = remote_message_count != local_message_count

                # Check for calendar changes if two-way sync is enabled
                calendar_changes = False
                calendar_change_desc = ""
                if two_way_calendar and vdir:
                    calendar_changes, calendar_change_desc = check_calendar_changes(
                        vdir, org
                    )

                # Determine what changed and show appropriate status
                if mail_changes and calendar_changes:
                    console.print(
                        create_status_display(
                            f"Changes detected! Mail: Remote {remote_message_count}, Local {local_message_count} | Calendar: {calendar_change_desc}. Starting sync...",
                            "yellow",
                        )
                    )
                elif mail_changes:
                    console.print(
                        create_status_display(
                            f"New messages detected! Remote: {remote_message_count}, Local: {local_message_count}. Starting sync...",
                            "yellow",
                        )
                    )
                elif calendar_changes:
                    console.print(
                        create_status_display(
                            f"Calendar changes detected! {calendar_change_desc}. Starting sync...",
                            "yellow",
                        )
                    )

                # Sync if any changes detected
                if mail_changes or calendar_changes:
                    await _sync_outlook_data(
                        dry_run,
                        vdir,
                        icsfile,
                        org,
                        days_back,
                        days_forward,
                        continue_iteration,
                        download_attachments,
                        two_way_calendar,
                    )
                    last_sync_time = time.time()
                    console.print(create_status_display("Sync completed ✅", "green"))
                else:
                    status_parts = [
                        f"Mail: Remote {remote_message_count}, Local {local_message_count}"
                    ]
                    if two_way_calendar:
                        status_parts.append(f"Calendar: {calendar_change_desc}")

                    console.print(
                        create_status_display(
                            f"No changes detected ({', '.join(status_parts)})",
                            "green",
                        )
                    )
            except Exception as e:
                console.print(
                    create_status_display(f"Error during check: {str(e)}", "red")
                )

        time.sleep(check_interval)