"""
Builds a user-safe, read-only capability summary for the Emma system prompt.
"""

from typing import List, Dict
from capability_registry import Availability, Capability, list_capabilities


def build_capability_system_context() -> str:
    """
    Builds a deterministic, user-safe, plain-text summary of capabilities.

    The output is structured for inclusion in a system prompt and must not leak
    internal details.
    """
    categorized: Dict[Availability, List[str]] = {
        Availability.ACTIVE: [],
        Availability.PLANNED: [],
        Availability.FORBIDDEN: [],
    }

    for capability in list_capabilities():
        if capability.availability == Availability.FORBIDDEN:
            if capability.id == "terminal.arbitrary_shell":
                categorized[Availability.FORBIDDEN].append(
                    "- Arbitrary terminal access is not available."
                )
            continue

        if capability.availability in categorized:
            categorized[capability.availability].append(
                f"- {capability.display_name}: {capability.description}"
            )

    output_lines = ["CURRENT CAPABILITY STATUS FOR THIS CHAT"]

    if categorized[Availability.ACTIVE]:
        output_lines.append("\nAvailable now:")
        output_lines.extend(categorized[Availability.ACTIVE])

    if categorized[Availability.PLANNED]:
        output_lines.append("\nPlanned, but not active in this chat:")
        output_lines.extend(categorized[Availability.PLANNED])

    if categorized[Availability.FORBIDDEN]:
        output_lines.append("\nUnavailable:")
        output_lines.extend(categorized[Availability.FORBIDDEN])

    output_lines.append(
        "\nRules:\n"
        "- Planned capabilities are not available in this chat and must not be claimed as active.\n"
        "- No tool, repository, deployment, memory, document retrieval, external service or state-changing action is activated by this capability summary.\n"
        "- Future write or high-impact capabilities require a concrete, explicit, bound user approval before execution."
    )

    return "\n".join(output_lines)