"""Render a snapshot with whatever labels the manifest supplies.

The text below is the shared explorer. It must not name a dataspace, a kind,
or a predicate. Those strings come from the snapshot and the manifest.
"""

from __future__ import annotations

from content_explorer.contract import resolve_claims


def render_explorer(snapshot: dict, manifest: dict) -> str:
    kinds = {kind["id"]: kind for kind in snapshot.get("kinds", [])}
    entities = {entity["id"]: entity for entity in snapshot.get("entities", [])}
    claims = snapshot.get("claims", [])
    policy = manifest.get("factPolicy", "show-all")
    lines: list[str] = [manifest["home"]["heading"], ""]

    for section in manifest.get("navigation", []):
        names = [kinds[kind_id]["plural"] for kind_id in section["kinds"] if kind_id in kinds]
        lines.append(f"{section['label']}: {', '.join(names)}")
    lines.append("")

    for kind_id in manifest["home"]["featuredKinds"]:
        kind = kinds.get(kind_id)
        if kind is None:
            continue
        lines.append(f"## {kind['plural']}")
        members = [entity for entity in snapshot.get("entities", []) if entity.get("kindId") == kind_id]
        if not members:
            lines.append("(none)")
        for entity in members:
            field = resolve_claims(
                [claim for claim in claims if claim.get("subjectId") == entity["id"]],
                "tldr",
                policy,
            )
            if field["state"] == "unknown":
                shown = "unknown"
            elif field["state"] == "contradicted":
                shown = "contested: " + " | ".join(str(value) for value in field["values"])
            elif field["state"] == "withheld":
                shown = "withheld"
            elif field["values"]:
                shown = str(field["values"][0])
            else:
                shown = entity.get("tldr", "")
            lines.append(f"- {entity['title']}: {shown}")
        lines.append("")

    lines.append("## Relations")
    labels = manifest.get("relationLabels") or {}
    for relation in snapshot.get("relations", []):
        predicate = relation["predicate"]
        wording = labels.get(predicate, {}).get("forward", predicate)
        origin = entities.get(relation["from"], {}).get("title", relation["from"])
        destination = entities.get(relation["to"], {}).get("title", relation["to"])
        lines.append(f"- {origin} — {wording} → {destination}")
    lines.append("")
    return "\n".join(lines).rstrip() + "\n"