"""Page helper registration for sx docs.

All helpers return data values (dicts, lists) — no sx_call(), no SxExpr.
Markup composition lives entirely in .sx files.
"""
from __future__ import annotations


def _register_sx_helpers() -> None:
    """Register Python data helpers as page helpers."""
    from shared.sx.pages import register_page_helpers
    from content.highlight import highlight as _highlight

    register_page_helpers("sx", {
        "highlight": _highlight,
        "primitives-data": _primitives_data,
        "reference-data": _reference_data,
        "attr-detail-data": _attr_detail_data,
        "read-spec-file": _read_spec_file,
    })


def _primitives_data() -> dict:
    """Return the PRIMITIVES dict for the primitives docs page."""
    from content.pages import PRIMITIVES
    return PRIMITIVES


def _reference_data(slug: str) -> dict:
    """Return reference table data for a given slug.

    Returns a dict whose keys become SX env bindings:
    - attributes: req-attrs, beh-attrs, uniq-attrs
    - headers: req-headers, resp-headers
    - events: events-list
    - js-api: js-api-list
    """
    from content.pages import (
        REQUEST_ATTRS, BEHAVIOR_ATTRS, SX_UNIQUE_ATTRS,
        REQUEST_HEADERS, RESPONSE_HEADERS,
        EVENTS, JS_API, ATTR_DETAILS,
    )

    if slug == "attributes":
        return {
            "req-attrs": [
                {"name": a, "desc": d, "exists": e,
                 "href": f"/reference/attributes/{a}" if e and a in ATTR_DETAILS else None}
                for a, d, e in REQUEST_ATTRS
            ],
            "beh-attrs": [
                {"name": a, "desc": d, "exists": e,
                 "href": f"/reference/attributes/{a}" if e and a in ATTR_DETAILS else None}
                for a, d, e in BEHAVIOR_ATTRS
            ],
            "uniq-attrs": [
                {"name": a, "desc": d, "exists": e,
                 "href": f"/reference/attributes/{a}" if e and a in ATTR_DETAILS else None}
                for a, d, e in SX_UNIQUE_ATTRS
            ],
        }
    elif slug == "headers":
        return {
            "req-headers": [
                {"name": n, "value": v, "desc": d}
                for n, v, d in REQUEST_HEADERS
            ],
            "resp-headers": [
                {"name": n, "value": v, "desc": d}
                for n, v, d in RESPONSE_HEADERS
            ],
        }
    elif slug == "events":
        return {
            "events-list": [
                {"name": n, "desc": d}
                for n, d in EVENTS
            ],
        }
    elif slug == "js-api":
        return {
            "js-api-list": [
                {"name": n, "desc": d}
                for n, d in JS_API
            ],
        }
    # Default — return attrs data for fallback
    return {
        "req-attrs": [
            {"name": a, "desc": d, "exists": e,
             "href": f"/reference/attributes/{a}" if e and a in ATTR_DETAILS else None}
            for a, d, e in REQUEST_ATTRS
        ],
        "beh-attrs": [
            {"name": a, "desc": d, "exists": e,
             "href": f"/reference/attributes/{a}" if e and a in ATTR_DETAILS else None}
            for a, d, e in BEHAVIOR_ATTRS
        ],
        "uniq-attrs": [
            {"name": a, "desc": d, "exists": e,
             "href": f"/reference/attributes/{a}" if e and a in ATTR_DETAILS else None}
            for a, d, e in SX_UNIQUE_ATTRS
        ],
    }


def _read_spec_file(filename: str) -> str:
    """Read a spec .sx file from the ref directory. Pure I/O — metadata lives in .sx."""
    import os
    ref_dir = os.path.join(os.path.dirname(__file__), "..", "..", "shared", "sx", "ref")
    if not os.path.isdir(ref_dir):
        ref_dir = "/app/shared/sx/ref"
    filepath = os.path.join(ref_dir, filename)
    try:
        with open(filepath, encoding="utf-8") as f:
            return f.read()
    except FileNotFoundError:
        return ";; spec file not found"


def _attr_detail_data(slug: str) -> dict:
    """Return attribute detail data for a specific attribute slug.

    Returns a dict whose keys become SX env bindings:
    - attr-title, attr-description, attr-example, attr-handler
    - attr-demo (component call or None)
    - attr-wire-id (wire placeholder id or None)
    - attr-not-found (truthy if not found)
    """
    from content.pages import ATTR_DETAILS
    from shared.sx.helpers import SxExpr

    detail = ATTR_DETAILS.get(slug)
    if not detail:
        return {"attr-not-found": True}

    demo_name = detail.get("demo")
    wire_id = None
    if "handler" in detail:
        wire_id = f"ref-wire-{slug.replace(':', '-').replace('*', 'star')}"

    return {
        "attr-not-found": None,
        "attr-title": slug,
        "attr-description": detail["description"],
        "attr-example": detail["example"],
        "attr-handler": detail.get("handler"),
        "attr-demo": SxExpr(f"(~{demo_name})") if demo_name else None,
        "attr-wire-id": wire_id,
    }