import {
  buildAssistantMcpDiscoveryAnswerDraft,
  type AssistantMcpDiscoveryAnswerDraftContract
} from "./assistantMcpDiscoveryAnswerAdapter";
import {
  executeAssistantMcpDiscoveryPilot,
  type AssistantMcpDiscoveryPilotExecutionContract,
  type AssistantMcpDiscoveryPilotExecutorDeps
} from "./assistantMcpDiscoveryPilotExecutor";
import {
  planAssistantMcpDiscovery,
  type AssistantMcpDiscoveryMetadataSurfaceRef,
  type AssistantMcpDiscoveryPlannerContract
} from "./assistantMcpDiscoveryPlanner";
import type { AssistantMcpDiscoveryDataNeedGraphContract } from "./assistantMcpDiscoveryDataNeedGraph";
import type { AssistantMcpDiscoveryTurnMeaningRef } from "./assistantMcpDiscoveryPolicy";

export const ASSISTANT_MCP_DISCOVERY_RUNTIME_BRIDGE_SCHEMA_VERSION =
  "assistant_mcp_discovery_runtime_bridge_v1" as const;

export type AssistantMcpDiscoveryRuntimeBridgeStatus =
  | "answer_draft_ready"
  | "checked_sources_only"
  | "needs_clarification"
  | "blocked"
  | "unsupported";

export interface AssistantMcpDiscoveryRuntimeBridgeInput {
  semanticDataNeed?: string | null;
  dataNeedGraph?: AssistantMcpDiscoveryDataNeedGraphContract | null;
  metadataSurface?: AssistantMcpDiscoveryMetadataSurfaceRef | null;
  turnMeaning?: AssistantMcpDiscoveryTurnMeaningRef | null;
  deps?: AssistantMcpDiscoveryPilotExecutorDeps;
}

export interface AssistantMcpDiscoveryRuntimeBridgeContract {
  schema_version: typeof ASSISTANT_MCP_DISCOVERY_RUNTIME_BRIDGE_SCHEMA_VERSION;
  policy_owner: "assistantMcpDiscoveryRuntimeBridge";
  bridge_status: AssistantMcpDiscoveryRuntimeBridgeStatus;
  hot_runtime_wired: false;
  planner: AssistantMcpDiscoveryPlannerContract;
  pilot: AssistantMcpDiscoveryPilotExecutionContract;
  answer_draft: AssistantMcpDiscoveryAnswerDraftContract;
  user_facing_response_allowed: boolean;
  business_fact_answer_allowed: boolean;
  requires_user_clarification: boolean;
  reason_codes: string[];
}

function normalizeReasonCode(value: string): string | null {
  const normalized = value
    .trim()
    .replace(/[^\p{L}\p{N}_.:-]+/gu, "_")
    .replace(/^_+|_+$/g, "")
    .toLowerCase();
  return normalized.length > 0 ? normalized.slice(0, 120) : null;
}

function pushReason(target: string[], value: string): void {
  const normalized = normalizeReasonCode(value);
  if (normalized && !target.includes(normalized)) {
    target.push(normalized);
  }
}

function uniqueStrings(values: string[]): string[] {
  const result: string[] = [];
  for (const value of values) {
    const text = String(value ?? "").trim();
    if (text && !result.includes(text)) {
      result.push(text);
    }
  }
  return result;
}

function bridgeStatusFor(
  pilot: AssistantMcpDiscoveryPilotExecutionContract,
  draft: AssistantMcpDiscoveryAnswerDraftContract
): AssistantMcpDiscoveryRuntimeBridgeStatus {
  if (draft.answer_mode === "blocked" || pilot.pilot_status === "blocked") {
    return "blocked";
  }
  if (draft.answer_mode === "needs_clarification" || pilot.pilot_status === "skipped_needs_clarification") {
    return "needs_clarification";
  }
  if (pilot.pilot_status === "unsupported") {
    return "unsupported";
  }
  if (draft.answer_mode === "checked_sources_only") {
    return "checked_sources_only";
  }
  return "answer_draft_ready";
}

function businessFactAnswerAllowed(draft: AssistantMcpDiscoveryAnswerDraftContract): boolean {
  return draft.answer_mode === "confirmed_with_bounded_inference" || draft.answer_mode === "bounded_inference_only";
}

export async function runAssistantMcpDiscoveryRuntimeBridge(
  input: AssistantMcpDiscoveryRuntimeBridgeInput
): Promise<AssistantMcpDiscoveryRuntimeBridgeContract> {
  const planner = planAssistantMcpDiscovery({
    semanticDataNeed: input.semanticDataNeed,
    dataNeedGraph: input.dataNeedGraph,
    metadataSurface: input.metadataSurface,
    turnMeaning: input.turnMeaning
  });
  const pilot = await executeAssistantMcpDiscoveryPilot(planner, input.deps);
  const answerDraft = buildAssistantMcpDiscoveryAnswerDraft(pilot);
  const bridgeStatus = bridgeStatusFor(pilot, answerDraft);
  const reasonCodes = uniqueStrings([...planner.reason_codes, ...pilot.reason_codes, ...answerDraft.reason_codes]);

  pushReason(reasonCodes, `runtime_bridge_status_${bridgeStatus}`);
  pushReason(reasonCodes, "runtime_bridge_not_wired_to_hot_assistant_answer");

  return {
    schema_version: ASSISTANT_MCP_DISCOVERY_RUNTIME_BRIDGE_SCHEMA_VERSION,
    policy_owner: "assistantMcpDiscoveryRuntimeBridge",
    bridge_status: bridgeStatus,
    hot_runtime_wired: false,
    planner,
    pilot,
    answer_draft: answerDraft,
    user_facing_response_allowed: bridgeStatus !== "blocked",
    business_fact_answer_allowed: businessFactAnswerAllowed(answerDraft),
    requires_user_clarification: bridgeStatus === "needs_clarification",
    reason_codes: reasonCodes
  };
}