# app/main.py

from flask import Blueprint, render_template, flash, redirect, url_for, abort, send_from_directory, request, jsonify

from sqlalchemy import desc, func, text, extract, and_
from sqlalchemy.orm import joinedload, aliased
from collections import OrderedDict
from datetime import datetime

from app.models import ImageRecord, Tag, ArchiveRecord, image_tags, ImportTask, ImportBatch
from app import db
import os
import shutil

main = Blueprint('main', __name__)


@main.route('/')
def index():
    """
    Showcase view: full-bleed masonry collage of random images/videos.
    """
    images = (
        ImageRecord.query
        .options(joinedload(ImageRecord.tags))
        .order_by(func.random())
        .limit(20)
        .all()
    )
    return render_template('showcase.html', images=images)


@main.route('/api/random-images')
def random_images_api():
    """
    JSON endpoint returning random images for shuffle/infinite scroll.

    Query params:
      - count: number of images to return (default 12)
      - exclude: comma-separated list of image IDs to exclude (for infinite scroll)
    """
    count = request.args.get('count', 12, type=int)
    exclude_str = request.args.get('exclude', '')

    # Parse exclusion list
    exclude_ids = []
    if exclude_str:
        try:
            exclude_ids = [int(x) for x in exclude_str.split(',') if x.strip()]
        except ValueError:
            pass

    # Build query
    q = ImageRecord.query.options(joinedload(ImageRecord.tags))

    if exclude_ids:
        q = q.filter(~ImageRecord.id.in_(exclude_ids))

    images = q.order_by(func.random()).limit(count).all()

    result = []
    for img in images:
        is_video = img.filename.lower().endswith(('.mp4', '.mov'))
        thumb_path = (img.thumb_path or img.filepath).replace('/images/', '')
        full_path = img.filepath.replace('/images/', '')

        result.append({
            'id': img.id,
            'filename': img.filename,
            'thumb_url': url_for('main.serve_image', filename=thumb_path),
            'full_url': url_for('main.serve_image', filename=full_path),
            'is_video': is_video,
            'date': (img.taken_at or img.imported_at).strftime('%Y-%m-%d') if (img.taken_at or img.imported_at) else '',
            'tags': [{'name': t.name, 'kind': t.kind} for t in img.tags]
        })

    return jsonify(images=result)


@main.route('/gallery')
def gallery():
    """
    Gallery with infinite scroll and year-month date dividers.
    Server renders initial batch, then JS takes over for infinite scroll.
    Optional tag filter via ?tag=artist:NAME or any tag name.
    """
    initial_limit = 30
    tag_name = request.args.get('tag')

    # Base query + eager-load tags
    q = ImageRecord.query.options(joinedload(ImageRecord.tags))

    # Optional tag filter
    if tag_name:
        q = q.join(ImageRecord.tags).filter(Tag.name == tag_name)

    # Fetch initial batch ordered by date descending
    images = q.order_by(
        desc(func.coalesce(ImageRecord.taken_at, ImageRecord.imported_at))
    ).limit(initial_limit + 1).all()

    # Check if there are more images
    has_more = len(images) > initial_limit
    if has_more:
        images = images[:initial_limit]

    # Group by year-month for initial render
    grouped_images = _group_images_by_month(images)

    # Compute initial cursor for JS to continue from
    initial_cursor = None
    if images and has_more:
        last_img = images[-1]
        last_dt = _get_image_date(last_img)
        if last_dt:
            initial_cursor = last_dt.isoformat()

    return render_template(
        'gallery.html',
        grouped_images=grouped_images,
        active_tag=tag_name,
        initial_cursor=initial_cursor,
        has_more=has_more
    )


@main.route('/images/<path:filename>')
def serve_image(filename):
    return send_from_directory('/images', filename)


# ----------------------------
# Gallery Infinite Scroll API
# ----------------------------

def _get_image_date(img):
    """Get the effective date for an image (taken_at or imported_at)."""
    return img.taken_at or img.imported_at


def _format_year_month(dt):
    """Format a datetime as year-month key and label."""
    if not dt:
        return 'unknown', 'Unknown Date'
    return dt.strftime('%Y-%m'), dt.strftime('%B %Y')


def _group_images_by_month(images):
    """
    Group images by year-month, preserving order.
    Returns list of (group_info, images) tuples.
    """
    groups = OrderedDict()

    for img in images:
        dt = _get_image_date(img)
        key, label = _format_year_month(dt)

        if key not in groups:
            groups[key] = {'key': key, 'label': label, 'images': []}

        groups[key]['images'].append(img)

    return [(info['key'], info['label'], info['images']) for info in groups.values()]


def _serialize_image(img):
    """Serialize an ImageRecord for JSON response."""
    is_video = img.filename.lower().endswith(('.mp4', '.mov'))
    thumb_path = (img.thumb_path or img.filepath).replace('/images/', '')
    full_path = img.filepath.replace('/images/', '')
    dt = _get_image_date(img)
    key, label = _format_year_month(dt)

    return {
        'id': img.id,
        'filename': img.filename,
        'thumb_url': url_for('main.serve_image', filename=thumb_path),
        'full_url': url_for('main.serve_image', filename=full_path),
        'is_video': is_video,
        'date': dt.strftime('%Y-%m-%d') if dt else '',
        'year_month': key,
        'year_month_label': label,
        'tags': [{'name': t.name, 'kind': t.kind} for t in img.tags if t.kind != 'archive']
    }


@main.route('/api/gallery/scroll')
def gallery_scroll():
    """
    Cursor-based infinite scroll endpoint with date grouping.

    Query params:
      - cursor: ISO datetime string for pagination (fetch images older than this)
      - limit: number of images per batch (default 30)
      - tag: optional tag filter

    Returns:
      - images: list of image objects with year_month grouping info
      - next_cursor: datetime string for next batch (null if no more)
      - date_groups: summary of year-month groups in this batch
      - has_more: boolean indicating if more images exist
    """
    cursor_str = request.args.get('cursor')
    limit = request.args.get('limit', 30, type=int)
    tag_name = request.args.get('tag')

    # Build base query
    q = ImageRecord.query.options(joinedload(ImageRecord.tags))

    # Optional tag filter
    if tag_name:
        q = q.join(ImageRecord.tags).filter(Tag.name == tag_name)

    # Apply cursor filter (fetch images older than cursor)
    if cursor_str:
        try:
            cursor_dt = datetime.fromisoformat(cursor_str.replace('Z', '+00:00'))
            q = q.filter(
                func.coalesce(ImageRecord.taken_at, ImageRecord.imported_at) < cursor_dt
            )
        except ValueError:
            pass  # Invalid cursor, ignore

    # Order by date descending and fetch with limit + 1 to check has_more
    images = q.order_by(
        desc(func.coalesce(ImageRecord.taken_at, ImageRecord.imported_at))
    ).limit(limit + 1).all()

    # Check if there are more images
    has_more = len(images) > limit
    if has_more:
        images = images[:limit]

    # Serialize images
    serialized = [_serialize_image(img) for img in images]

    # Build date_groups summary
    groups_seen = OrderedDict()
    for s in serialized:
        key = s['year_month']
        if key not in groups_seen:
            groups_seen[key] = {'key': key, 'label': s['year_month_label'], 'count': 0}
        groups_seen[key]['count'] += 1

    # Compute next cursor
    next_cursor = None
    if images and has_more:
        last_img = images[-1]
        last_dt = _get_image_date(last_img)
        if last_dt:
            next_cursor = last_dt.isoformat()

    return jsonify(
        images=serialized,
        next_cursor=next_cursor,
        has_more=has_more,
        date_groups=list(groups_seen.values())
    )


@main.route('/api/gallery/timeline')
def gallery_timeline():
    """
    Returns all year-month groups with counts for timeline navigation.

    Query params:
      - tag: optional tag filter (same as gallery)

    Returns list of {key, label, count, year} ordered newest to oldest.
    """
    tag_name = request.args.get('tag')

    # Use SQL to aggregate by year-month
    date_expr = func.coalesce(ImageRecord.taken_at, ImageRecord.imported_at)

    q = db.session.query(
        extract('year', date_expr).label('year'),
        extract('month', date_expr).label('month'),
        func.count(ImageRecord.id).label('count')
    )

    if tag_name:
        q = q.join(ImageRecord.tags).filter(Tag.name == tag_name)

    q = q.group_by(
        extract('year', date_expr),
        extract('month', date_expr)
    ).order_by(
        extract('year', date_expr).desc(),
        extract('month', date_expr).desc()
    )

    results = q.all()

    # Format results
    groups = []
    for row in results:
        if row.year and row.month:
            year = int(row.year)
            month = int(row.month)
            key = f"{year:04d}-{month:02d}"
            # Create a date object to format the month name
            dt = datetime(year, month, 1)
            label = dt.strftime('%B %Y')
            short_label = dt.strftime('%b')  # Short month name for sidebar
            groups.append({
                'key': key,
                'label': label,
                'short_label': short_label,
                'year': year,
                'month': month,
                'count': row.count
            })

    return jsonify(groups=groups)


@main.route('/api/gallery/jump')
def gallery_jump():
    """
    Fetch images starting from a specific year-month for timeline jump navigation.

    Query params:
      - year_month: target year-month (e.g., '2024-03')
      - limit: number of images (default 30)
      - tag: optional tag filter

    Returns same format as /api/gallery/scroll but starting from the target month.
    """
    year_month = request.args.get('year_month', '')
    limit = request.args.get('limit', 30, type=int)
    tag_name = request.args.get('tag')

    if not year_month:
        return jsonify(error='year_month is required'), 400

    try:
        # Parse year-month to get start of that month
        target_dt = datetime.strptime(year_month + '-01', '%Y-%m-%d')
        # Get end of month (start of next month)
        if target_dt.month == 12:
            next_month = datetime(target_dt.year + 1, 1, 1)
        else:
            next_month = datetime(target_dt.year, target_dt.month + 1, 1)
    except ValueError:
        return jsonify(error='Invalid year_month format'), 400

    # Build query for images in that month and earlier
    q = ImageRecord.query.options(joinedload(ImageRecord.tags))

    if tag_name:
        q = q.join(ImageRecord.tags).filter(Tag.name == tag_name)

    # Get images from start of target month onwards (but ordered descending)
    date_expr = func.coalesce(ImageRecord.taken_at, ImageRecord.imported_at)
    q = q.filter(date_expr < next_month)

    images = q.order_by(desc(date_expr)).limit(limit + 1).all()

    has_more = len(images) > limit
    if has_more:
        images = images[:limit]

    serialized = [_serialize_image(img) for img in images]

    # Build date_groups summary
    groups_seen = OrderedDict()
    for s in serialized:
        key = s['year_month']
        if key not in groups_seen:
            groups_seen[key] = {'key': key, 'label': s['year_month_label'], 'count': 0}
        groups_seen[key]['count'] += 1

    next_cursor = None
    if images and has_more:
        last_img = images[-1]
        last_dt = _get_image_date(last_img)
        if last_dt:
            next_cursor = last_dt.isoformat()

    return jsonify(
        images=serialized,
        next_cursor=next_cursor,
        has_more=has_more,
        date_groups=list(groups_seen.values()),
        target_year_month=year_month
    )


@main.route('/tags')
def tag_list():
    """
    Generic tag explorer:
      /tags            -> all tags
      /tags?kind=user  -> only user tags
      /tags?kind=artist -> only artist tags
      /tags?kind=archive -> only archive tags
      /tags?kind=character -> only character tags
      /tags?kind=series -> only series tags
      /tags?kind=rating -> only rating tags
    Shows a few preview images per tag.

    Optimized to use 2 queries instead of N+1:
    1. Get all tags with counts
    2. Get preview images for all tags at once using window function
    """
    images_per_tag = 3
    kind = request.args.get('kind')

    # Query 1: Get tags with image counts
    q = db.session.query(
        Tag,
        func.count(image_tags.c.image_id).label('img_count')
    ).outerjoin(image_tags).group_by(Tag.id)

    if kind:
        q = q.filter(Tag.kind == kind)

    tags_with_counts = q.order_by(Tag.name.asc()).all()

    # Build tag_id list and initialize tag_data dict
    tag_ids = [t.id for t, _ in tags_with_counts]
    tag_map = {}
    for t, count in tags_with_counts:
        label = t.name.split(":", 1)[1] if (":" in t.name) else t.name
        tag_map[t.id] = {
            "id": t.id,
            "name": label,
            "tag": t.name,
            "images": [],
            "kind": t.kind,
            "count": count
        }

    # Query 2: Get preview images for all tags at once using a subquery with row_number
    # This fetches the top N images per tag in a single query
    if tag_ids:
        # Subquery to rank images within each tag
        row_num = func.row_number().over(
            partition_by=image_tags.c.tag_id,
            order_by=desc(func.coalesce(ImageRecord.taken_at, ImageRecord.imported_at))
        ).label('rn')

        subq = (
            db.session.query(
                image_tags.c.tag_id,
                ImageRecord.id.label('image_id'),
                row_num
            )
            .join(ImageRecord, ImageRecord.id == image_tags.c.image_id)
            .filter(image_tags.c.tag_id.in_(tag_ids))
            .subquery()
        )

        # Get only the top N images per tag
        preview_rows = (
            db.session.query(subq.c.tag_id, ImageRecord)
            .join(ImageRecord, ImageRecord.id == subq.c.image_id)
            .filter(subq.c.rn <= images_per_tag)
            .all()
        )

        # Group images by tag_id
        for tag_id, img in preview_rows:
            if tag_id in tag_map:
                tag_map[tag_id]["images"].append(img)

    # Convert to list maintaining original order
    tag_data = [tag_map[t.id] for t, _ in tags_with_counts]

    return render_template('tags_list.html',
                           tag_data=tag_data,
                           images_per_tag=images_per_tag,
                           active_kind=kind)

@main.route('/artists')
def artist_list():
    # Backward-compatible route that now shows the Tag Explorer filtered to artist tags
    return redirect(url_for('main.tag_list', kind='artist'))

@main.route('/artist/<artist_name>')
def artist_gallery(artist_name):
    # Backward-compatible: go to gallery filtered by artist tag
    return redirect(url_for('main.gallery', tag=f"artist:{artist_name}"))


@main.route('/settings')
def settings():
    return render_template('settings.html')


@main.route('/trigger-thumbnail-generation', methods=['POST'])
def trigger_thumbnail_generation():
    try:
        with open('/import/thumbnail.flag', 'w') as f:
            f.write("trigger")
        flash("Thumbnail regeneration has been triggered.", "success")
    except Exception as e:
        flash(f"Failed to trigger thumbnail regeneration: {e}", "danger")

    return redirect(url_for('main.settings'))


@main.route('/import-images')
def trigger_image_import():
    with open('/import/trigger.flag', 'w') as f:
        f.write('start')
    flash("Image import triggered.", "success")
    return redirect(url_for('main.settings'))


@main.route('/reset-db', methods=['POST'])
def reset_db():
    """
    Safe reset that works with Postgres (TRUNCATE ... CASCADE).
    Falls back to ordered deletes if TRUNCATE isn't supported (e.g., SQLite).
    """
    try:
        # Postgres fast path
        db.session.execute(text("""
            TRUNCATE TABLE image_tags, archive_record, image_record, tag
            RESTART IDENTITY CASCADE
        """))
        db.session.commit()
    except Exception:
        # Fallback: manual delete order
        db.session.execute(image_tags.delete())
        ArchiveRecord.query.delete()
        ImageRecord.query.delete()
        Tag.query.delete()
        db.session.commit()

    # Optional: clear thumbs on disk to regenerate fresh
    shutil.rmtree("/images/thumbs", ignore_errors=True)
    os.makedirs("/images/thumbs", exist_ok=True)

    flash("Database has been reset. All records removed.", "info")
    return redirect(url_for('main.settings'))


# ----------------------------
# Tag add/remove endpoints
# ----------------------------

@main.get("/api/tags/search")
def search_tags():
    """
    Search existing tags for autocomplete.
    Query params:
      - q: search query (matches tag name, case-insensitive)
      - limit: max results (default 10)
      - exclude_kind: comma-separated list of tag kinds to exclude (e.g., 'archive')
    """
    query = request.args.get('q', '').strip().lower()
    limit = request.args.get('limit', 10, type=int)
    exclude_kind = request.args.get('exclude_kind', '').strip()
    exclude_kinds = [k.strip() for k in exclude_kind.split(',') if k.strip()]

    if not query:
        # Return most-used tags when no query
        base_query = (
            Tag.query
            .join(image_tags)
            .group_by(Tag.id)
        )
        if exclude_kinds:
            base_query = base_query.filter(~Tag.kind.in_(exclude_kinds))
        tags = (
            base_query
            .order_by(func.count(image_tags.c.image_id).desc())
            .limit(limit)
            .all()
        )
    else:
        base_query = Tag.query.filter(Tag.name.ilike(f'%{query}%'))
        if exclude_kinds:
            base_query = base_query.filter(~Tag.kind.in_(exclude_kinds))
        tags = (
            base_query
            .order_by(Tag.name)
            .limit(limit)
            .all()
        )

    return jsonify(tags=[{"id": t.id, "name": t.name, "kind": t.kind} for t in tags])


@main.get("/image/<int:image_id>/tags")
def list_tags(image_id):
    img = ImageRecord.query.get_or_404(image_id)
    return jsonify(ok=True, tags=[{"name": t.name, "kind": t.kind} for t in img.tags])


@main.post("/image/<int:image_id>/tags/add")
def add_tag(image_id):
    """
    Minimal JSON endpoint to add a tag to an image.
    Accepts either 'artist:NAME' / 'archive:...' or a bare freeform tag ('mytag').
    """
    name = (request.form.get("name") or "").strip()
    if not name:
        abort(400)

    # Normalize: keep explicit kind prefixes, otherwise treat as user tag
    if ":" in name:
        kind = name.split(":", 1)[0]
        tag_name = name
    else:
        kind = "user"
        tag_name = name

    img = ImageRecord.query.get_or_404(image_id)
    tag = Tag.query.filter_by(name=tag_name).first()
    if not tag:
        tag = Tag(name=tag_name, kind=kind)
        db.session.add(tag)
        db.session.flush()
    if tag not in img.tags:
        img.tags.append(tag)
        db.session.commit()
    return jsonify(ok=True, tag={"name": tag.name, "kind": tag.kind})


@main.post("/image/<int:image_id>/tags/remove")
def remove_tag(image_id):
    """
    Minimal JSON endpoint to remove a tag from an image.
    """
    name = (request.form.get("name") or "").strip()
    img = ImageRecord.query.get_or_404(image_id)
    tag = Tag.query.filter_by(name=name).first()
    if tag and tag in img.tags:
        img.tags.remove(tag)
        db.session.commit()
    return jsonify(ok=True)


# ----------------------------
# Tag management endpoints
# ----------------------------

@main.get("/api/tag/<int:tag_id>")
def get_tag(tag_id):
    """Get a single tag's details."""
    tag = Tag.query.get_or_404(tag_id)
    # Get display name (without prefix)
    display_name = tag.name.split(":", 1)[1] if ":" in tag.name else tag.name
    return jsonify(ok=True, tag={
        "id": tag.id,
        "name": tag.name,
        "display_name": display_name,
        "kind": tag.kind
    })


@main.post("/api/tag/<int:tag_id>/update")
def update_tag(tag_id):
    """
    Update a tag's name and/or kind.
    For prefixed kinds (artist, archive, character, series, rating),
    the name will be stored as 'kind:name'.

    If the new name matches an existing tag, merge them:
    - Move all images from source tag to target tag
    - Delete the source tag
    - Return the target tag info with merged=True
    """
    tag = Tag.query.get_or_404(tag_id)

    new_name = (request.form.get("name") or "").strip()
    new_kind = (request.form.get("kind") or "user").strip()
    force_merge = request.form.get("merge") == "true"

    if not new_name:
        return jsonify(ok=False, error="Name is required"), 400

    # Build the full tag name based on kind
    prefixed_kinds = ("artist", "archive", "character", "series", "rating")
    if new_kind in prefixed_kinds:
        # Remove any existing prefix from name if present
        if ":" in new_name:
            new_name = new_name.split(":", 1)[1]
        full_name = f"{new_kind}:{new_name}"
    else:
        # User tags don't have prefixes
        full_name = new_name

    # Check for duplicates (excluding current tag)
    existing = Tag.query.filter(Tag.name == full_name, Tag.id != tag_id).first()
    if existing:
        if not force_merge:
            # Ask user to confirm merge
            return jsonify(
                ok=False,
                error="A tag with this name already exists",
                can_merge=True,
                target_tag={
                    "id": existing.id,
                    "name": existing.name,
                    "kind": existing.kind
                }
            ), 409  # Conflict status

        # Merge: move all images from source tag to target tag
        source_images = tag.images[:]  # Copy list to avoid mutation during iteration
        merged_count = 0
        for img in source_images:
            if existing not in img.tags:
                img.tags.append(existing)
                merged_count += 1
            img.tags.remove(tag)

        # Delete the source tag
        db.session.delete(tag)
        db.session.commit()

        return jsonify(ok=True, merged=True, merged_count=merged_count, tag={
            "id": existing.id,
            "name": existing.name,
            "kind": existing.kind
        })

    # No conflict - just update the tag
    tag.name = full_name
    tag.kind = new_kind
    db.session.commit()

    return jsonify(ok=True, tag={
        "id": tag.id,
        "name": tag.name,
        "kind": tag.kind
    })


@main.post("/api/tag/<int:tag_id>/delete")
def delete_tag(tag_id):
    """Delete a tag entirely."""
    tag = Tag.query.get_or_404(tag_id)

    # Remove from all images first (handled by cascade, but explicit is clearer)
    db.session.delete(tag)
    db.session.commit()

    return jsonify(ok=True)


# ----------------------------
# Filtered deletion endpoints
# ----------------------------

@main.post("/api/delete-by-tag")
def delete_images_by_tag():
    """
    Delete all images that have a specific tag.
    Also removes the image files and thumbnails from disk.
    Query params:
      - tag_id: ID of the tag whose images should be deleted
      - tag_name: Name of the tag (must match for security validation)
      - delete_tag: if "true", also delete the tag itself
    """
    tag_id = request.form.get("tag_id", type=int)
    tag_name = request.form.get("tag_name", "").strip()
    delete_tag_also = request.form.get("delete_tag") == "true"

    if not tag_id:
        return jsonify(ok=False, error="tag_id is required"), 400

    if not tag_name:
        return jsonify(ok=False, error="tag_name confirmation is required"), 400

    tag = Tag.query.get_or_404(tag_id)

    # Security: verify the provided tag name matches the actual tag
    if tag.name != tag_name:
        return jsonify(ok=False, error="Tag name confirmation does not match"), 403

    images_to_delete = list(tag.images)

    deleted_count = 0
    errors = []

    for img in images_to_delete:
        try:
            # Remove image file from disk
            if img.filepath and os.path.exists(img.filepath):
                os.remove(img.filepath)
            # Remove thumbnail if exists
            if img.thumb_path and os.path.exists(img.thumb_path):
                os.remove(img.thumb_path)
            # Delete DB record
            db.session.delete(img)
            deleted_count += 1
        except Exception as e:
            errors.append(f"Failed to delete {img.filename}: {e}")

    # Optionally delete the tag itself
    if delete_tag_also:
        db.session.delete(tag)

    db.session.commit()

    return jsonify(
        ok=True,
        deleted_count=deleted_count,
        tag_deleted=delete_tag_also,
        errors=errors if errors else None
    )


@main.get("/api/tag/<int:tag_id>/image-count")
def get_tag_image_count(tag_id):
    """Get the number of images associated with a tag."""
    tag = Tag.query.get_or_404(tag_id)
    count = len(tag.images)
    return jsonify(ok=True, count=count, tag_name=tag.name)


# ----------------------------
# Import settings endpoints
# ----------------------------

@main.get("/api/import-settings")
def get_import_settings():
    """Get current import filter settings from database."""
    from app.utils.version_migration import (
        get_setting_int, get_setting_float, get_setting_bool
    )

    settings = {
        "min_width": get_setting_int("import_min_width", int(os.environ.get("IMPORT_MIN_WIDTH", "0"))),
        "min_height": get_setting_int("import_min_height", int(os.environ.get("IMPORT_MIN_HEIGHT", "0"))),
        "skip_transparent": get_setting_bool("import_skip_transparent", os.environ.get("IMPORT_SKIP_TRANSPARENT", "false").lower() == "true"),
        "transparency_threshold": get_setting_float("import_transparency_threshold", float(os.environ.get("IMPORT_TRANSPARENCY_THRESHOLD", "0.9"))),
        "phash_threshold": get_setting_int("phash_threshold", int(os.environ.get("IMPORT_PHASH_THRESHOLD", "10"))),
    }
    return jsonify(ok=True, settings=settings)


@main.post("/api/import-settings")
def save_import_settings():
    """
    Save import filter settings to database.
    Settings are loaded by the Celery workers via load_import_settings().
    """
    from app.utils.version_migration import set_setting

    min_width = request.form.get("min_width", 0, type=int)
    min_height = request.form.get("min_height", 0, type=int)
    skip_transparent = request.form.get("skip_transparent") == "true"
    transparency_threshold = request.form.get("transparency_threshold", 0.9, type=float)
    phash_threshold = request.form.get("phash_threshold", 10, type=int)

    try:
        set_setting("import_min_width", str(min_width))
        set_setting("import_min_height", str(min_height))
        set_setting("import_skip_transparent", str(skip_transparent).lower())
        set_setting("import_transparency_threshold", str(transparency_threshold))
        set_setting("phash_threshold", str(phash_threshold))

        settings = {
            "min_width": min_width,
            "min_height": min_height,
            "skip_transparent": skip_transparent,
            "transparency_threshold": transparency_threshold,
            "phash_threshold": phash_threshold,
        }
        return jsonify(ok=True, settings=settings)
    except Exception as e:
        return jsonify(ok=False, error=str(e)), 500


@main.get("/api/import-stats")
def get_import_stats():
    """Get import statistics including filtered image counts."""
    import json
    stats_path = "/import/stats.json"
    try:
        if os.path.exists(stats_path):
            with open(stats_path, "r") as f:
                stats = json.load(f)
        else:
            stats = {
                "total_processed": 0,
                "total_imported": 0,
                "filtered_by_dimension": 0,
                "filtered_by_transparency": 0,
                "filtered_by_duplicate": 0,
            }
        return jsonify(ok=True, stats=stats)
    except Exception as e:
        return jsonify(ok=False, error=str(e)), 500


# ----------------------------
# Image filter/cleanup endpoints
# ----------------------------

@main.get("/api/filter-scan")
def scan_filterable_images():
    """
    Scan existing images against current filter settings.
    Returns counts and IDs of images that would be filtered.
    Query params:
      - filter_type: 'transparency' or 'dimensions'
      - threshold: for transparency (0.0-1.0), or min_width/min_height for dimensions
      - min_width: minimum width (for dimensions filter)
      - min_height: minimum height (for dimensions filter)
      - limit: max results to return (default 100)
    """
    from app.utils.image_importer import is_mostly_transparent

    filter_type = request.args.get("filter_type", "transparency")
    limit = request.args.get("limit", 100, type=int)

    results = []

    if filter_type == "transparency":
        threshold = request.args.get("threshold", 0.9, type=float)

        # Only check images that could have transparency
        images = ImageRecord.query.filter(
            ImageRecord.filepath.ilike("%.png") |
            ImageRecord.filepath.ilike("%.gif") |
            ImageRecord.filepath.ilike("%.webp")
        ).limit(limit * 5).all()  # Check more to find enough matches

        for img in images:
            if len(results) >= limit:
                break
            if img.filepath and os.path.exists(img.filepath):
                try:
                    if is_mostly_transparent(img.filepath, threshold):
                        results.append({
                            "id": img.id,
                            "filename": img.filename,
                            "filepath": img.filepath,
                            "thumb_url": url_for('main.serve_image',
                                filename=(img.thumb_path or img.filepath).replace('/images/', ''))
                        })
                except Exception:
                    pass

    elif filter_type == "dimensions":
        min_width = request.args.get("min_width", 0, type=int)
        min_height = request.args.get("min_height", 0, type=int)

        if min_width <= 0 and min_height <= 0:
            return jsonify(ok=True, count=0, images=[], message="No dimension filter set")

        query = ImageRecord.query
        if min_width > 0:
            query = query.filter(ImageRecord.width < min_width)
        if min_height > 0:
            query = query.filter(ImageRecord.height < min_height)

        images = query.limit(limit).all()

        for img in images:
            results.append({
                "id": img.id,
                "filename": img.filename,
                "filepath": img.filepath,
                "width": img.width,
                "height": img.height,
                "thumb_url": url_for('main.serve_image',
                    filename=(img.thumb_path or img.filepath).replace('/images/', ''))
            })

    # Get total count (without limit) for progress indication
    total_count = len(results)

    return jsonify(ok=True, count=total_count, images=results, filter_type=filter_type)


@main.post("/api/filter-delete")
def delete_filtered_images():
    """
    Delete images by their IDs after filter review.
    Query params:
      - image_ids: comma-separated list of image IDs to delete
      - confirm: must be 'true' to actually delete
    """
    image_ids_str = request.form.get("image_ids", "")
    confirm = request.form.get("confirm") == "true"

    if not confirm:
        return jsonify(ok=False, error="Confirmation required"), 400

    if not image_ids_str:
        return jsonify(ok=False, error="No image IDs provided"), 400

    try:
        image_ids = [int(x) for x in image_ids_str.split(",") if x.strip()]
    except ValueError:
        return jsonify(ok=False, error="Invalid image IDs"), 400

    deleted_count = 0
    errors = []

    for img_id in image_ids:
        img = ImageRecord.query.get(img_id)
        if not img:
            continue

        try:
            # Remove image file from disk
            if img.filepath and os.path.exists(img.filepath):
                os.remove(img.filepath)
            # Remove thumbnail if exists
            if img.thumb_path and os.path.exists(img.thumb_path):
                os.remove(img.thumb_path)
            # Delete DB record
            db.session.delete(img)
            deleted_count += 1
        except Exception as e:
            errors.append(f"Failed to delete {img.filename}: {e}")

    db.session.commit()

    return jsonify(
        ok=True,
        deleted_count=deleted_count,
        errors=errors if errors else None
    )


# ----------------------------
# Import Task Queue API (Celery)
# ----------------------------

@main.route('/api/import/trigger', methods=['POST'])
def trigger_import_celery():
    """
    Trigger a directory scan and import via Celery.
    Replaces the old flag-file mechanism.
    """
    try:
        from app.tasks.scan import scan_directory

        source_dir = request.form.get('source_dir', '/import')
        dest_dir = request.form.get('dest_dir', '/images')

        result = scan_directory.delay(source_dir, dest_dir)

        return jsonify({
            'ok': True,
            'task_id': result.id,
            'message': 'Import scan started'
        })
    except Exception as e:
        return jsonify({'ok': False, 'error': str(e)}), 500


@main.route('/api/import/status')
def import_queue_status():
    """
    Get current import queue status.
    Returns counts by task status and recent task info.
    """
    try:
        # Count tasks by status
        status_counts = dict(
            db.session.query(
                ImportTask.status,
                func.count(ImportTask.id)
            ).group_by(ImportTask.status).all()
        )

        # Get active batch info
        active_batch = ImportBatch.query.filter_by(status='running').order_by(
            ImportBatch.started_at.desc()
        ).first()

        # Recent tasks (last 20)
        recent_tasks = ImportTask.query.order_by(
            ImportTask.created_at.desc()
        ).limit(20).all()

        return jsonify({
            'ok': True,
            'status_counts': {
                'pending': status_counts.get('pending', 0),
                'queued': status_counts.get('queued', 0),
                'processing': status_counts.get('processing', 0),
                'complete': status_counts.get('complete', 0),
                'failed': status_counts.get('failed', 0),
                'skipped': status_counts.get('skipped', 0),
            },
            'active_batch': {
                'id': active_batch.id,
                'source_directory': active_batch.source_directory,
                'total_files': active_batch.total_files,
                'processed_files': active_batch.processed_files,
                'imported_count': active_batch.imported_count,
                'skipped_count': active_batch.skipped_count,
                'failed_count': active_batch.failed_count,
                'started_at': active_batch.started_at.isoformat() if active_batch.started_at else None
            } if active_batch else None,
            'recent_tasks': [
                {
                    'id': t.id,
                    'source_path': os.path.basename(t.source_path) if t.source_path else None,
                    'task_type': t.task_type,
                    'status': t.status,
                    'error_message': t.error_message[:100] if t.error_message else None,
                    'created_at': t.created_at.isoformat() if t.created_at else None
                }
                for t in recent_tasks
            ]
        })
    except Exception as e:
        return jsonify({'ok': False, 'error': str(e)}), 500


@main.route('/api/import/task/<int:task_id>')
def get_import_task(task_id):
    """
    Get detailed status for a specific import task.
    """
    task = ImportTask.query.get_or_404(task_id)

    # Check Celery task status if still processing
    celery_status = None
    if task.celery_task_id:
        try:
            from app.celery_app import celery
            result = celery.AsyncResult(task.celery_task_id)
            celery_status = result.status
        except Exception:
            pass

    return jsonify({
        'ok': True,
        'task': {
            'id': task.id,
            'source_path': task.source_path,
            'file_hash': task.file_hash,
            'file_size': task.file_size,
            'task_type': task.task_type,
            'status': task.status,
            'celery_status': celery_status,
            'celery_task_id': task.celery_task_id,
            'error_message': task.error_message,
            'retry_count': task.retry_count,
            'context': task.context,
            'batch_id': task.batch_id,
            'result_image_id': task.result_image_id,
            'created_at': task.created_at.isoformat() if task.created_at else None,
            'started_at': task.started_at.isoformat() if task.started_at else None,
            'completed_at': task.completed_at.isoformat() if task.completed_at else None
        }
    })


@main.route('/api/import/retry-failed', methods=['POST'])
def retry_failed_import_tasks():
    """
    Re-queue all failed import tasks.
    """
    try:
        from app.tasks.import_file import import_media_file, import_archive

        failed_tasks = ImportTask.query.filter_by(status='failed').all()
        retried = 0

        for task in failed_tasks:
            task.status = 'pending'
            task.error_message = None
            task.retry_count = 0
            task.started_at = None
            task.completed_at = None

            if task.task_type == 'import_image':
                result = import_media_file.delay(task.id)
            elif task.task_type == 'import_archive':
                result = import_archive.delay(task.id)
            else:
                continue

            task.celery_task_id = result.id
            task.status = 'queued'
            retried += 1

        db.session.commit()

        return jsonify({
            'ok': True,
            'retried': retried
        })
    except Exception as e:
        db.session.rollback()
        return jsonify({'ok': False, 'error': str(e)}), 500


@main.route('/api/import/clear-completed', methods=['POST'])
def clear_completed_tasks():
    """
    Clear completed and skipped import tasks from the database.
    Keeps failed tasks for review.
    """
    try:
        deleted = ImportTask.query.filter(
            ImportTask.status.in_(['complete', 'skipped'])
        ).delete(synchronize_session=False)

        db.session.commit()

        return jsonify({
            'ok': True,
            'deleted': deleted
        })
    except Exception as e:
        db.session.rollback()
        return jsonify({'ok': False, 'error': str(e)}), 500


@main.route('/api/thumbnails/regenerate', methods=['POST'])
def regenerate_thumbnails_celery():
    """
    Trigger thumbnail regeneration for all images via Celery.
    """
    try:
        from app.tasks.thumbnail import regenerate_all_thumbnails

        overwrite = request.form.get('overwrite', 'true').lower() == 'true'
        result = regenerate_all_thumbnails.delay(overwrite=overwrite)

        return jsonify({
            'ok': True,
            'task_id': result.id,
            'message': 'Thumbnail regeneration started'
        })
    except Exception as e:
        return jsonify({'ok': False, 'error': str(e)}), 500


@main.route('/api/thumbnails/regenerate-missing', methods=['POST'])
def regenerate_missing_thumbnails_celery():
    """
    Generate thumbnails only for images that don't have them.
    """
    try:
        from app.tasks.thumbnail import regenerate_missing_thumbnails

        result = regenerate_missing_thumbnails.delay()

        return jsonify({
            'ok': True,
            'task_id': result.id,
            'message': 'Missing thumbnail generation started'
        })
    except Exception as e:
        return jsonify({'ok': False, 'error': str(e)}), 500


@main.route('/api/celery/status')
def celery_cluster_status():
    """
    Get Celery cluster status (workers, queues, etc.).
    """
    try:
        from app.celery_app import celery

        inspect = celery.control.inspect()

        # Get worker stats
        active = inspect.active() or {}
        scheduled = inspect.scheduled() or {}
        reserved = inspect.reserved() or {}
        stats = inspect.stats() or {}

        # Count active tasks
        active_count = sum(len(tasks) for tasks in active.values())

        return jsonify({
            'ok': True,
            'workers': list(stats.keys()),
            'worker_count': len(stats),
            'active_tasks': active_count,
            'active': active,
            'scheduled': scheduled,
            'reserved': reserved
        })
    except Exception as e:
        return jsonify({
            'ok': False,
            'error': str(e),
            'message': 'Celery may not be running'
        }), 503


@main.route('/api/import/batches')
def list_import_batches():
    """
    List recent import batches with statistics.
    """
    limit = request.args.get('limit', 10, type=int)

    batches = ImportBatch.query.order_by(
        ImportBatch.started_at.desc()
    ).limit(limit).all()

    return jsonify({
        'ok': True,
        'batches': [
            {
                'id': b.id,
                'source_directory': b.source_directory,
                'status': b.status,
                'total_files': b.total_files,
                'processed_files': b.processed_files,
                'imported_count': b.imported_count,
                'skipped_count': b.skipped_count,
                'failed_count': b.failed_count,
                'started_at': b.started_at.isoformat() if b.started_at else None,
                'completed_at': b.completed_at.isoformat() if b.completed_at else None
            }
            for b in batches
        ]
    })


# =============================================
# Duplicate Detection API
# =============================================

@main.route('/api/duplicates/scan', methods=['POST'])
def scan_duplicates():
    """
    Scan for duplicate images using perceptual hash comparison.
    Returns groups of similar images within the specified hamming distance.
    """
    import imagehash

    threshold = request.form.get('threshold', 10, type=int)
    limit = request.form.get('limit', 100, type=int)

    # Get all images with perceptual hashes
    images = ImageRecord.query.filter(
        ImageRecord.perceptual_hash.isnot(None)
    ).all()

    if not images:
        return jsonify({'ok': True, 'groups': [], 'message': 'No images with perceptual hashes found'})

    # Build hash lookup
    hash_data = []
    for img in images:
        try:
            phash = imagehash.hex_to_hash(img.perceptual_hash)
            hash_data.append({
                'id': img.id,
                'hash': phash,
                'width': img.width,
                'height': img.height,
                'filename': img.filename,
                'filepath': img.filepath,
                'thumb_path': img.thumb_path,
                'file_size': img.file_size
            })
        except Exception:
            continue

    # Find duplicate groups
    duplicate_groups = []
    processed = set()

    for i, img1 in enumerate(hash_data):
        if img1['id'] in processed:
            continue

        group = [img1]

        for j, img2 in enumerate(hash_data[i+1:], start=i+1):
            if img2['id'] in processed:
                continue

            distance = img1['hash'] - img2['hash']
            if distance <= threshold:
                group.append(img2)
                processed.add(img2['id'])

        if len(group) > 1:
            processed.add(img1['id'])
            # Sort group by resolution (largest first)
            group.sort(key=lambda x: x['width'] * x['height'], reverse=True)
            duplicate_groups.append(group)

        if len(duplicate_groups) >= limit:
            break

    # Format response
    result_groups = []
    for group in duplicate_groups:
        result_groups.append([
            {
                'id': img['id'],
                'filename': img['filename'],
                'width': img['width'],
                'height': img['height'],
                'file_size': img['file_size'],
                'thumb_url': url_for('main.serve_image',
                    filename=(img['thumb_path'] or img['filepath']).replace('/images/', ''))
            }
            for img in group
        ])

    return jsonify({
        'ok': True,
        'groups': result_groups,
        'total_groups': len(result_groups),
        'threshold': threshold
    })


@main.route('/api/duplicates/delete', methods=['POST'])
def delete_duplicates():
    """
    Delete specified duplicate images.
    Expects JSON body with 'image_ids' array.
    """
    data = request.get_json() or {}
    image_ids = data.get('image_ids', [])

    if not image_ids:
        return jsonify({'ok': False, 'error': 'No image IDs provided'})

    deleted_count = 0
    errors = []

    for image_id in image_ids:
        try:
            image = ImageRecord.query.get(image_id)
            if not image:
                errors.append(f"Image {image_id} not found")
                continue

            # Delete physical files
            if image.filepath and os.path.exists(image.filepath):
                os.remove(image.filepath)
            if image.thumb_path and os.path.exists(image.thumb_path):
                os.remove(image.thumb_path)

            # Delete database record
            db.session.delete(image)
            deleted_count += 1

        except Exception as e:
            errors.append(f"Error deleting {image_id}: {str(e)}")

    db.session.commit()

    return jsonify({
        'ok': True,
        'deleted_count': deleted_count,
        'errors': errors if errors else None
    })


# =============================================
# Bulk Tag Operations API
# =============================================

@main.route('/api/images/common-tags', methods=['POST'])
def get_common_tags():
    """
    Get tags that are common to all specified images.
    Expects JSON body with 'image_ids' array.
    Returns tags that appear on EVERY selected image.
    """
    data = request.get_json() or {}
    image_ids = data.get('image_ids', [])

    if not image_ids:
        return jsonify({'ok': True, 'tags': []})

    # Find tags that appear on ALL selected images
    # We use a subquery approach: count occurrences of each tag and filter
    # for tags where the count equals the number of images
    num_images = len(image_ids)

    # Query: get tags where the count of associated images (from our list) equals num_images
    common_tags = db.session.query(Tag).join(image_tags).filter(
        image_tags.c.image_id.in_(image_ids)
    ).group_by(Tag.id).having(
        func.count(image_tags.c.image_id) == num_images
    ).order_by(Tag.name).all()

    return jsonify({
        'ok': True,
        'tags': [
            {'id': t.id, 'name': t.name, 'kind': t.kind}
            for t in common_tags
        ]
    })


@main.route('/api/images/bulk-add-tag', methods=['POST'])
def bulk_add_tag():
    """
    Add a tag to multiple images at once.
    Expects JSON body with 'image_ids' array and 'tag_name' string.
    """
    data = request.get_json() or {}
    image_ids = data.get('image_ids', [])
    tag_name = (data.get('tag_name') or '').strip()

    if not image_ids:
        return jsonify({'ok': False, 'error': 'No image IDs provided'}), 400

    if not tag_name:
        return jsonify({'ok': False, 'error': 'No tag name provided'}), 400

    # Determine tag kind from name
    if ':' in tag_name:
        kind = tag_name.split(':', 1)[0]
    else:
        kind = 'user'

    # Get or create the tag
    tag = Tag.query.filter_by(name=tag_name).first()
    if not tag:
        tag = Tag(name=tag_name, kind=kind)
        db.session.add(tag)
        db.session.flush()

    # Get images that don't already have this tag
    images = ImageRecord.query.filter(
        ImageRecord.id.in_(image_ids)
    ).all()

    added_count = 0
    for img in images:
        if tag not in img.tags:
            img.tags.append(tag)
            added_count += 1

    db.session.commit()

    return jsonify({
        'ok': True,
        'added_count': added_count,
        'tag': {'id': tag.id, 'name': tag.name, 'kind': tag.kind}
    })


@main.route('/api/images/bulk-remove-tag', methods=['POST'])
def bulk_remove_tag():
    """
    Remove a tag from multiple images at once.
    Expects JSON body with 'image_ids' array and 'tag_name' string.
    """
    data = request.get_json() or {}
    image_ids = data.get('image_ids', [])
    tag_name = (data.get('tag_name') or '').strip()

    if not image_ids:
        return jsonify({'ok': False, 'error': 'No image IDs provided'}), 400

    if not tag_name:
        return jsonify({'ok': False, 'error': 'No tag name provided'}), 400

    # Find the tag
    tag = Tag.query.filter_by(name=tag_name).first()
    if not tag:
        return jsonify({'ok': True, 'removed_count': 0, 'message': 'Tag not found'})

    # Get images that have this tag
    images = ImageRecord.query.filter(
        ImageRecord.id.in_(image_ids)
    ).all()

    removed_count = 0
    for img in images:
        if tag in img.tags:
            img.tags.remove(tag)
            removed_count += 1

    db.session.commit()

    return jsonify({
        'ok': True,
        'removed_count': removed_count
    })