"""Locate tablet documents, including the parts of a large checked copy."""
from pathlib import Path

from copienator import configuration
from copienator.json_io import read_json


def annotation_limits() -> tuple[int, int]:
    values = (configuration.ANNOTATION_MAX_HEIGHT_PX, configuration.ANNOTATION_MAX_PIXELS)
    for name, value in zip(("ANNOTATION_MAX_HEIGHT_PX", "ANNOTATION_MAX_PIXELS"), values):
        if type(value) is not int or value <= 0:
            raise ValueError(f"{name} must be a positive integer (pixels)")
    return values


# Validate global settings at import, as before.
annotation_limits()


def document_fits(width: int, height: int, max_height: int, max_pixels: int) -> bool:
    return height <= max_height and width * height <= max_pixels


def copy_documents(directory: Path) -> list[Path]:
    try:
        metadata = read_json(directory / "bnote.json", default={})
    except (OSError, ValueError):
        # Ordinary documents need no manifest. Let the reader report bad metadata.
        return [directory]
    parts = metadata.get("parts", []) if isinstance(metadata, dict) else []
    return [directory / name for name in parts] if parts else [directory]


def tablet_documents(root: Path) -> list[tuple[str, Path]]:
    documents = []
    for directory in sorted(root.iterdir()):
        if not directory.is_dir():
            continue
        for part in copy_documents(directory):
            name = directory.name if part == directory else f"{directory.name} {part.name}"
            documents.append((name, part))
    return documents