import fs from "fs";
import { ASSISTANT_CAPABILITIES_REGISTRY_FILE } from "../config";

export type CapabilityMaturity = "production_ready" | "partial" | "planned" | "deprecated";

export interface CapabilityGroup {
  group_code: string;
  group_title: string;
  description: string;
  risk_level: "low" | "medium" | "high";
  maturity_status: CapabilityMaturity;
  supported_operations: string[];
  unsupported_operations: string[];
  required_entities: string[];
  optional_entities: string[];
  typical_queries: string[];
  related_routes: string[];
  safe_alternatives: string[];
  one_c_hints: string[];
}

export interface CapabilityRegistry {
  schema_version: string;
  updated_at: string;
  assistant_mode: "read_only" | "mixed";
  groups: CapabilityGroup[];
}

const FALLBACK_REGISTRY: CapabilityRegistry = {
  schema_version: "capabilities_registry_fallback_v1",
  updated_at: "2026-04-09T00:00:00.000Z",
  assistant_mode: "read_only",
  groups: [
    {
      group_code: "vat",
      group_title: "НДС",
      description: "Срезы и расчеты НДС на базе данных 1С.",
      risk_level: "high",
      maturity_status: "partial",
      supported_operations: ["vat_period_snapshot", "vat_payable_forecast"],
      unsupported_operations: ["submit_tax_declaration"],
      required_entities: ["period", "organization"],
      optional_entities: ["counterparty"],
      typical_queries: ["Сколько НДС к уплате за период?"],
      related_routes: [],
      safe_alternatives: ["Показать движения по 68/19 за период"],
      one_c_hints: ["РегистрБухгалтерии.Хозрасчетный"]
    },
    {
      group_code: "counterparties",
      group_title: "Контрагенты",
      description: "Документы, операции, договоры и срезы по контрагентам.",
      risk_level: "medium",
      maturity_status: "production_ready",
      supported_operations: ["list_documents_by_counterparty", "list_contracts_by_counterparty"],
      unsupported_operations: ["edit_counterparty_card"],
      required_entities: ["counterparty_scope_or_contract"],
      optional_entities: ["period", "organization"],
      typical_queries: ["Покажи документы по контрагенту"],
      related_routes: [],
      safe_alternatives: ["Уточнить ИНН/наименование контрагента"],
      one_c_hints: ["Справочник.Контрагенты"]
    },
    {
      group_code: "boundaries",
      group_title: "Ограничения",
      description: "Операции, которые ассистент не выполняет.",
      risk_level: "high",
      maturity_status: "production_ready",
      supported_operations: ["explain_boundary", "suggest_safe_next_step"],
      unsupported_operations: ["configure_1c", "admin_server_actions", "create_or_post_documents"],
      required_entities: [],
      optional_entities: [],
      typical_queries: ["Можешь настроить 1С?"],
      related_routes: [],
      safe_alternatives: ["Сформировать план диагностики для 1С/ИТ-админа"],
      one_c_hints: []
    }
  ]
};

let cache: { mtimeMs: number; value: CapabilityRegistry } | null = null;

function toRecord(value: unknown): Record<string, unknown> | null {
  if (!value || typeof value !== "object" || Array.isArray(value)) return null;
  return value as Record<string, unknown>;
}

function toStringSafe(value: unknown): string | null {
  if (typeof value !== "string") return null;
  const trimmed = value.trim();
  return trimmed.length > 0 ? trimmed : null;
}

function toArray(value: unknown): unknown[] {
  return Array.isArray(value) ? value : [];
}

function readRegistryFromFile(): CapabilityRegistry | null {
  if (!fs.existsSync(ASSISTANT_CAPABILITIES_REGISTRY_FILE)) return null;
  try {
    const raw = fs.readFileSync(ASSISTANT_CAPABILITIES_REGISTRY_FILE, "utf-8");
    const parsed = JSON.parse(raw) as unknown;
    const root = toRecord(parsed);
    if (!root) return null;
    const groups = toArray(root.groups)
      .map((item) => toRecord(item))
      .filter((item): item is Record<string, unknown> => item !== null)
      .map((item) => ({
        group_code: toStringSafe(item.group_code) ?? "unknown_group",
        group_title: toStringSafe(item.group_title) ?? "Группа",
        description: toStringSafe(item.description) ?? "",
        risk_level: (toStringSafe(item.risk_level) as "low" | "medium" | "high" | null) ?? "medium",
        maturity_status:
          (toStringSafe(item.maturity_status) as CapabilityMaturity | null) ??
          ("partial" as CapabilityMaturity),
        supported_operations: toArray(item.supported_operations)
          .map((v) => toStringSafe(v))
          .filter((v): v is string => v !== null),
        unsupported_operations: toArray(item.unsupported_operations)
          .map((v) => toStringSafe(v))
          .filter((v): v is string => v !== null),
        required_entities: toArray(item.required_entities)
          .map((v) => toStringSafe(v))
          .filter((v): v is string => v !== null),
        optional_entities: toArray(item.optional_entities)
          .map((v) => toStringSafe(v))
          .filter((v): v is string => v !== null),
        typical_queries: toArray(item.typical_queries)
          .map((v) => toStringSafe(v))
          .filter((v): v is string => v !== null),
        related_routes: toArray(item.related_routes)
          .map((v) => toStringSafe(v))
          .filter((v): v is string => v !== null),
        safe_alternatives: toArray(item.safe_alternatives)
          .map((v) => toStringSafe(v))
          .filter((v): v is string => v !== null),
        one_c_hints: toArray(item.one_c_hints)
          .map((v) => toStringSafe(v))
          .filter((v): v is string => v !== null)
      }));

    if (groups.length === 0) return null;

    return {
      schema_version: toStringSafe(root.schema_version) ?? "capabilities_registry_v1",
      updated_at: toStringSafe(root.updated_at) ?? new Date().toISOString(),
      assistant_mode: (toStringSafe(root.assistant_mode) as "read_only" | "mixed" | null) ?? "read_only",
      groups
    };
  } catch {
    return null;
  }
}

export function loadCapabilitiesRegistry(): CapabilityRegistry {
  try {
    const mtimeMs = fs.existsSync(ASSISTANT_CAPABILITIES_REGISTRY_FILE)
      ? fs.statSync(ASSISTANT_CAPABILITIES_REGISTRY_FILE).mtimeMs
      : -1;
    if (cache && cache.mtimeMs === mtimeMs) {
      return cache.value;
    }
    const value = readRegistryFromFile() ?? FALLBACK_REGISTRY;
    cache = { mtimeMs, value };
    return value;
  } catch {
    return cache?.value ?? FALLBACK_REGISTRY;
  }
}

export function buildCapabilityContractReplyFromRegistry(): string {
  const registry = loadCapabilitiesRegistry();
  const topGroups = registry.groups.slice(0, 6);
  const groupLines = topGroups.map((group, index) => {
    const ops = group.supported_operations.slice(0, 3).join(", ");
    return `${index + 1}. ${group.group_title}: ${group.description}${ops ? ` (например: ${ops})` : ""}.`;
  });

  return [
    "Я ассистент по анализу данных 1С в режиме чтения.",
    "Что умею по группам:",
    ...groupLines,
    "Если хотите, раскрою любую группу точечно и дам готовую формулировку запроса.",
    "Что не делаю: не настраиваю 1С, не меняю конфигурацию, не создаю и не провожу документы, не выполняю админ-действия на сервере."
  ].join("\n");
}

export function resolveNearestCapabilityGroup(input: { domain?: string | null; queryClass?: string | null }): CapabilityGroup | null {
  const registry = loadCapabilitiesRegistry();
  const haystack = `${String(input.domain ?? "")} ${String(input.queryClass ?? "")}`.toLowerCase();
  if (!haystack.trim()) return null;

  const scoring: Array<{ group: CapabilityGroup; score: number }> = registry.groups.map((group) => {
    let score = 0;
    const bucket = `${group.group_code} ${group.group_title} ${group.description} ${group.supported_operations.join(" ")}`.toLowerCase();
    for (const token of haystack.split(/[\s._/-]+/g).filter(Boolean)) {
      if (bucket.includes(token)) score += 1;
    }
    return { group, score };
  });

  scoring.sort((a, b) => b.score - a.score);
  return scoring[0] && scoring[0].score > 0 ? scoring[0].group : null;
}