from __future__ import annotations

import re
import unicodedata

from sqlalchemy.ext.asyncio import AsyncSession

from shared.contracts.dtos import MarketPlaceDTO
from shared.services.registry import services


class MarketError(ValueError):
    """Base error for market service operations."""


def slugify(value: str, max_len: int = 255) -> str:
    if value is None:
        value = ""
    value = unicodedata.normalize("NFKD", value)
    value = value.encode("ascii", "ignore").decode("ascii")
    value = value.lower()
    value = value.replace("/", "-")
    value = re.sub(r"[^a-z0-9]+", "-", value)
    value = re.sub(r"-{2,}", "-", value)
    value = value.strip("-")[:max_len].strip("-")
    return value or "market"


async def create_market(sess: AsyncSession, post_id: int, name: str) -> MarketPlaceDTO:
    """
    Create a market for a page. Name must be unique per page.
    If a market with the same (post_id, slug) exists but is soft-deleted,
    it will be revived.
    """
    name = (name or "").strip()
    if not name:
        raise MarketError("Market name must not be empty.")
    slug = slugify(name)

    post = await services.blog.get_post_by_id(sess, post_id)
    if not post:
        raise MarketError(f"Post {post_id} does not exist.")
    if not post.is_page:
        raise MarketError("Markets can only be created on pages, not posts.")

    try:
        return await services.market.create_marketplace(sess, "page", post_id, name, slug)
    except ValueError as e:
        raise MarketError(str(e)) from e


async def soft_delete(sess: AsyncSession, post_slug: str, market_slug: str) -> bool:
    post = await services.blog.get_post_by_slug(sess, post_slug)
    if not post:
        return False

    return await services.market.soft_delete_marketplace(sess, "page", post.id, market_slug)