"""funnies crossword construction.

Per functional design (BR1.2 / Q1=B): AI-assisted — an injectable clue-drafter
(typically the cloud model) supplies across/down clues; funnies lays them out
onto a 10x10 grid (Q2=B). The clue-drafter is injectable so tests stub it (no
real network in CI). The grid layout is deterministic/dependency-free.
"""

from __future__ import annotations

from typing import Protocol

from .model import Crossword


class ClueDrafter(Protocol):
    """Interface for the AI-assisted clue drafting (the sanctioned cloud call)."""

    def draft_clues(
        self, theme_words: list[str], context: str, grid_size: int
    ) -> tuple[list[str], list[str]]: ...


class StubClueDrafter:
    """Deterministic stub used in tests / offline: simple auto-clues."""

    def draft_clues(self, theme_words, context, grid_size=10):
        across = [f"Word {i + 1}" for i in range(len(theme_words))]
        down = ["Crossing clue"] * min(4, len(theme_words))
        return across, down


GRID_SIZE = 10


def _blank_grid() -> list[list[str]]:
    return [[" " for _ in range(GRID_SIZE)] for _ in range(GRID_SIZE)]


def _lay_out_across(words: list[str], base: list[list[str]]) -> None:
    """Place theme words horizontally on row r for the grid."""
    for r, word in enumerate(words[:GRID_SIZE]):
        if r >= GRID_SIZE:
            break
        w = word[:GRID_SIZE]
        base[r][: len(w)] = list(w.upper())


def build_crossword(
    theme_words: list[str],
    context: str,
    clue_drafter: ClueDrafter | None = None,
) -> Crossword:
    """Build a 10x10 crossword with AI-drafted clues (BR1.2, Q2=B)."""
    drafter = clue_drafter or StubClueDrafter()
    across, down = drafter.draft_clues(theme_words, context, GRID_SIZE)
    grid = _blank_grid()
    _lay_out_across(theme_words, grid)
    solution = [row[:] for row in grid]
    return Crossword(
        crossword_id="xw-1",
        grid=grid,
        clues_across=across,
        clues_down=down,
        solution=solution,
    )