"""Routes for Wiki CRUD operations."""

import re

from flask_jwt_extended import get_jwt_identity, jwt_required
from flask_pydantic import validate
from sqlalchemy import and_
from sqlalchemy import delete as sql_delete
from sqlalchemy import select

from app import db
from app.decorators import serialize_list_response, serialize_response
from app.models import Board, Wiki, wiki_entity_links
from app.models.card import Card
from app.models.epic import Epic
from app.schemas import (CardResponse, EpicResponse, WikiCreateRequest,
                         WikiLinkRequest, WikiResponse, WikiUpdateRequest)

from . import kanban_bp


def generate_slug(name):
    """Generate URL-friendly slug from name."""
    slug = name.lower()
    slug = re.sub(r"[^a-z0-9\s-]", "", slug)
    slug = re.sub(r"\s+", "-", slug)
    slug = slug.strip("-")
    return slug


@kanban_bp.route("/boards/<int:board_id>/wikis", methods=["GET"])
@jwt_required()
@serialize_list_response(WikiResponse)
def get_board_wikis(board_id):
    """Get all wikis for a board."""
    board = db.session.get(Board, board_id)
    if not board:
        return {"error": "Board not found"}, 404

    wikis = Wiki.query.filter_by(board_id=board_id).all()
    return wikis, 200


@kanban_bp.route("/boards/<int:board_id>/wikis", methods=["POST"])
@jwt_required()
@validate(body=WikiCreateRequest)
@serialize_response(WikiResponse)
def create_wiki(board_id, body: WikiCreateRequest):
    """Create a new wiki for a board."""
    board = db.session.get(Board, board_id)
    if not board:
        return {"error": "Board not found"}, 404

    # Generate slug if not provided
    slug = body.slug
    if not slug:
        slug = generate_slug(body.name)

        # Ensure uniqueness
        counter = 1
        original_slug = slug
        while Wiki.query.filter_by(slug=slug).first():
            slug = f"{original_slug}-{counter}"
            counter += 1

    wiki = Wiki(
        board_id=board_id,
        name=body.name,
        slug=slug,
        content=body.content,
        summary=body.summary,
        category=body.category,
        tags=body.tags,
        created_by=get_jwt_identity(),
        updated_by=get_jwt_identity(),
    )

    db.session.add(wiki)
    db.session.commit()

    return wiki, 201


@kanban_bp.route("/wikis/<int:wiki_id>", methods=["GET"])
@jwt_required()
def get_wiki(wiki_id):
    """Get a specific wiki with details including linked entities."""
    wiki = db.session.get(Wiki, wiki_id)
    if not wiki:
        return {"error": "Wiki not found"}, 404

    # Convert wiki to dict and add linked entities
    wiki_dict = wiki.to_dict()

    # Add linked cards
    linked_cards = [
        CardResponse.model_validate(card).model_dump() for card in wiki.linked_cards
    ]

    # Add linked epics
    linked_epics = [
        EpicResponse.model_validate(epic).model_dump() for epic in wiki.linked_epics
    ]

    wiki_dict["linked_cards"] = linked_cards
    wiki_dict["linked_epics"] = linked_epics

    return wiki_dict, 200


@kanban_bp.route("/wikis/<int:wiki_id>", methods=["PUT"])
@jwt_required()
@validate(body=WikiUpdateRequest)
@serialize_response(WikiResponse)
def update_wiki(wiki_id, body: WikiUpdateRequest):
    """Update a wiki."""
    wiki = db.session.get(Wiki, wiki_id)
    if not wiki:
        return {"error": "Wiki not found"}, 404

    # Update fields
    if body.name is not None:
        wiki.name = body.name
    if body.slug is not None:
        wiki.slug = body.slug
    if body.content is not None:
        wiki.content = body.content
    if body.summary is not None:
        wiki.summary = body.summary
    if body.category is not None:
        wiki.category = body.category
    if body.tags is not None:
        wiki.tags = body.tags

    wiki.updated_by = get_jwt_identity()
    db.session.commit()

    return wiki, 200


@kanban_bp.route("/wikis/<int:wiki_id>", methods=["DELETE"])
@jwt_required()
def delete_wiki(wiki_id):
    """Delete a wiki."""
    wiki = db.session.get(Wiki, wiki_id)
    if not wiki:
        return {"error": "Wiki not found"}, 404

    # Delete wiki (cascades to wiki_entity_links)
    db.session.delete(wiki)
    db.session.commit()

    return {"message": "Wiki deleted successfully"}, 200


@kanban_bp.route("/wikis/<int:wiki_id>/links", methods=["POST"])
@jwt_required()
@validate(body=WikiLinkRequest)
def create_wiki_link(wiki_id, body: WikiLinkRequest):
    """Link a wiki to another entity (card, epic, list, or board)."""
    wiki = db.session.get(Wiki, wiki_id)
    if not wiki:
        return {"error": "Wiki not found"}, 404

    # Check if entity exists
    entity = None
    if body.entity_type == "card":
        entity = db.session.get(Card, body.entity_id)
    elif body.entity_type == "epic":
        entity = db.session.get(Epic, body.entity_id)
    elif body.entity_type == "list":
        from app.models.list_model import List

        entity = db.session.get(List, body.entity_id)
    elif body.entity_type == "board":
        entity = db.session.get(Board, body.entity_id)

    if not entity:
        return {"error": f"{body.entity_type.capitalize()} not found"}, 404

    # Check if link already exists
    existing_link = db.session.scalars(
        select(wiki_entity_links).where(
            and_(
                wiki_entity_links.c.wiki_id == wiki_id,
                wiki_entity_links.c.entity_type == body.entity_type,
                wiki_entity_links.c.entity_id == body.entity_id,
            )
        )
    ).first()

    if existing_link:
        return {"error": "Link already exists"}, 400

    # Create link using core insert
    stmt = wiki_entity_links.insert().values(
        wiki_id=wiki_id,
        entity_type=body.entity_type,
        entity_id=body.entity_id,
        linked_by=get_jwt_identity(),
    )
    db.session.execute(stmt)
    db.session.commit()

    return {"message": "Link created successfully"}, 201


@kanban_bp.route("/wikis/<int:wiki_id>/links", methods=["DELETE"])
@jwt_required()
@validate(body=WikiLinkRequest)
def delete_wiki_link(wiki_id, body: WikiLinkRequest):
    """Delete a wiki entity link."""
    wiki = db.session.get(Wiki, wiki_id)
    if not wiki:
        return {"error": "Wiki not found"}, 404

    # Delete link using core delete
    stmt = sql_delete(wiki_entity_links).where(
        and_(
            wiki_entity_links.c.wiki_id == wiki_id,
            wiki_entity_links.c.entity_type == body.entity_type,
            wiki_entity_links.c.entity_id == body.entity_id,
        )
    )
    result = db.session.execute(stmt)

    if result.rowcount == 0:
        return {"error": "Link not found"}, 404

    db.session.commit()

    return {"message": "Link deleted successfully"}, 200