"""Tenant-level credibility flags derived from project external_context."""
from __future__ import annotations

from typing import Any, Dict


def build_credibility_flags(external_context: Dict[str, Any] | None) -> Dict[str, Any]:
    ctx = external_context or {}
    existing = ctx.get("credibility_flags")
    if isinstance(existing, dict) and existing:
        return dict(existing)

    reg_quality = (ctx.get("regulation_link_quality") or "unknown").lower()
    msp = ctx.get("msp_analysis") or {}
    using_real = bool(
        ctx.get("msp_using_real_data")
        or msp.get("using_real_data")
        or msp.get("data_source") in ("gus", "regon", "msp_live")
    )
    grounded = bool(ctx.get("regulation_grounded") or ctx.get("precise_regulation_url"))
    snapshot = ctx.get("snapshot_data") or {}
    has_snapshot = bool(snapshot.get("key_rules") or snapshot.get("version_hash"))

    warnings: list[str] = []
    if reg_quality in ("unknown", "listing", "low"):
        warnings.append("regulation_link_weak")
    if not using_real:
        warnings.append("msp_not_grounded")
    if not has_snapshot:
        warnings.append("missing_regulation_snapshot")

    if reg_quality == "high" and using_real and has_snapshot:
        level = "high"
    elif reg_quality in ("high", "medium") and grounded:
        level = "medium"
    else:
        level = "needs_attention"

    return {
        "overall_trust_level": level,
        "msp_using_real_data": using_real,
        "regulation_link_quality": reg_quality,
        "regulation_grounded": grounded,
        "has_regulation_snapshot": has_snapshot,
        "warnings": warnings,
    }