"""Validate listing `attributes` against a category's `field_schema`.

Returns (cleaned_attributes, errors). Caller rejects on any errors.
Supported field types: text, number, select, bool.
"""

_HOT_COLUMNS = {"condition", "job_type", "salary_min", "salary_max"}


class SchemaError(ValueError):
    pass


def validate_attributes(category, raw):
    raw = raw or {}
    cleaned, errors = {}, {}

    for field in category.fields():
        name = field["name"]
        ftype = field.get("type", "text")
        required = field.get("required", False)
        val = raw.get(name)

        if val in (None, "", []):
            if required:
                errors[name] = "required"
            continue

        try:
            cleaned[name] = _coerce(field, ftype, val)
        except SchemaError as e:
            errors[name] = str(e)

    return cleaned, errors


def _coerce(field, ftype, val):
    if ftype == "text":
        s = str(val).strip()
        mx = field.get("max", 255)
        if len(s) > mx:
            raise SchemaError(f"max length {mx}")
        return s

    if ftype == "number":
        try:
            n = int(val) if str(val).lstrip("-").isdigit() else float(val)
        except (TypeError, ValueError):
            raise SchemaError("must be a number")
        if "min" in field and n < field["min"]:
            raise SchemaError(f"min {field['min']}")
        if "max" in field and n > field["max"]:
            raise SchemaError(f"max {field['max']}")
        return n

    if ftype == "select":
        opts = field.get("options", [])
        if val not in opts:
            raise SchemaError("invalid option")
        return val

    if ftype == "bool":
        return bool(val) if isinstance(val, bool) else str(val).lower() in ("1", "true", "on", "yes")

    raise SchemaError("unknown field type")


def hot_values(cleaned):
    """Map cleaned attributes -> denormalized Listing hot columns."""
    return {
        "attr_condition": cleaned.get("condition"),
        "attr_job_type": cleaned.get("job_type"),
        "attr_salary_min": cleaned.get("salary_min"),
        "attr_salary_max": cleaned.get("salary_max"),
    }