/**
 * @module mcp-server/tools/security
 * MCP Tool: BGP security — hijack detection, route leak analysis (ASPA-based),
 * bogon filtering, and blacklist checks.
 *
 * Provides security-focused analysis of BGP routing using RPKI ROV and ASPA
 * validation from bgproutes.io, combined with historical data from RIPE Stat
 * and other sources.
 */

import { z } from "zod";
import type { ASN, AnomalySeverity } from "../../types/common.js";

// ── Tool Schemas ─────────────────────────────────────────

/** Input schema for hijack detection */
export const hijackDetectionSchema = z.object({
  prefix: z
    .string()
    .describe("IP prefix to check for hijacks (e.g., '1.1.1.0/24')"),
  expectedOriginAsn: z
    .number()
    .optional()
    .describe("Expected origin ASN (if known)"),
  includeHistory: z
    .boolean()
    .optional()
    .default(true)
    .describe("Include historical hijack events"),
});

/** Input schema for ASPA-based route leak detection */
export const routeLeakDetectionSchema = z.object({
  asn: z
    .union([z.string(), z.number()])
    .describe("ASN to check for route leaks involving their prefixes"),
  prefixes: z
    .array(z.string())
    .optional()
    .describe("Specific prefixes to check (default: all announced by ASN)"),
  timeRange: z
    .object({
      start: z.string().describe("Start time (ISO 8601)"),
      end: z.string().describe("End time (ISO 8601)"),
    })
    .optional()
    .describe("Time range to search for leaks"),
});

/** Input schema for bogon check */
export const bogonCheckSchema = z.object({
  asn: z
    .union([z.string(), z.number()])
    .describe("ASN to check for bogon origination or path issues"),
  includeReserved: z
    .boolean()
    .optional()
    .default(true)
    .describe("Check for reserved/unallocated prefix announcements"),
  includeBogonAsns: z
    .boolean()
    .optional()
    .default(true)
    .describe("Check for bogon ASNs in AS paths"),
});

/** Input schema for blacklist check */
export const blacklistCheckSchema = z.object({
  resource: z
    .string()
    .describe("IP address, prefix, or ASN to check against blacklists"),
  lists: z
    .array(z.string())
    .optional()
    .describe("Specific blacklists to check (default: all known)"),
});

// ── Result Types ─────────────────────────────────────────

/** Detected BGP hijack */
export interface HijackEvent {
  readonly prefix: string;
  readonly legitimateOrigin: ASN;
  readonly hijackerAsn: ASN;
  readonly hijackerName: string;
  readonly type: "exact-match" | "sub-prefix" | "squat";
  readonly severity: AnomalySeverity;
  readonly rpkiStatus: "valid" | "invalid" | "not-found" | "unknown";
  readonly firstSeen: string;
  readonly lastSeen: string;
  readonly affectedPaths: number;
  readonly description: string;
}

/** Hijack detection result */
export interface HijackDetectionResult {
  readonly prefix: string;
  readonly expectedOriginAsn: ASN | null;
  readonly currentOrigins: ReadonlyArray<{
    readonly asn: ASN;
    readonly name: string;
    readonly rpkiValid: boolean;
  }>;
  readonly activeHijacks: ReadonlyArray<HijackEvent>;
  readonly historicalHijacks: ReadonlyArray<HijackEvent>;
  readonly riskLevel: AnomalySeverity;
  readonly recommendations: ReadonlyArray<string>;
}

/** ASPA-based route leak event */
export interface RouteLeakEvent {
  readonly prefix: string;
  readonly leakerAsn: ASN;
  readonly leakerName: string;
  readonly leakedTo: ReadonlyArray<ASN>;
  readonly aspaValidation: {
    readonly state: "invalid";
    readonly violatingHop: {
      readonly asn: ASN;
      readonly position: number;
      readonly reason: string;
    };
  };
  readonly severity: AnomalySeverity;
  readonly firstSeen: string;
  readonly lastSeen: string;
  readonly description: string;
}

/** Route leak detection result */
export interface RouteLeakDetectionResult {
  readonly asn: ASN;
  readonly name: string;
  readonly prefixesChecked: number;
  readonly activeLeaks: ReadonlyArray<RouteLeakEvent>;
  readonly historicalLeaks: ReadonlyArray<RouteLeakEvent>;
  readonly aspaStatus: {
    readonly hasAspaObjects: boolean;
    readonly aspaObjectCount: number;
    readonly coveragePercent: number;
  };
  readonly riskLevel: AnomalySeverity;
  readonly recommendations: ReadonlyArray<string>;
}

/** Bogon check finding */
export interface BogonFinding {
  readonly type: "bogon_prefix" | "bogon_asn" | "reserved_prefix" | "unallocated_prefix";
  readonly resource: string;
  readonly severity: AnomalySeverity;
  readonly description: string;
  readonly asPath: ReadonlyArray<ASN>;
}

/** Bogon check result */
export interface BogonCheckResult {
  readonly asn: ASN;
  readonly findings: ReadonlyArray<BogonFinding>;
  readonly bogonPrefixCount: number;
  readonly bogonAsnInPathCount: number;
  readonly clean: boolean;
  readonly recommendations: ReadonlyArray<string>;
}

/** Blacklist check result */
export interface BlacklistCheckResult {
  readonly resource: string;
  readonly listed: boolean;
  readonly listings: ReadonlyArray<{
    readonly list: string;
    readonly listedSince: string;
    readonly reason: string;
    readonly delistUrl: string;
  }>;
  readonly clean: boolean;
}

// ── Tool Handlers ────────────────────────────────────────

/**
 * Detect active and historical BGP hijacks for a prefix.
 *
 * Checks for unauthorized origin ASes, sub-prefix hijacks, and route
 * squatting using RPKI ROV validation and MOAS conflict detection.
 *
 * @param input - Validated detection parameters
 * @returns Hijack detection result with active/historical events
 *
 * @example
 * ```
 * > Check if 1.1.1.0/24 is being hijacked
 *
 * Returns: Current origins, RPKI validation, any MOAS conflicts,
 * and historical hijack events.
 * ```
 */
export async function handleHijackDetection(
  input: z.infer<typeof hijackDetectionSchema>
): Promise<HijackDetectionResult> {
  // TODO: Query bgproutes.io RIB for current origins of this prefix
  // TODO: Validate each origin via RPKI ROV
  // TODO: Compare with expected origin if provided
  // TODO: Check for sub-prefix announcements (more-specific hijacks)
  // TODO: Query historical data from RIPE Stat BGP updates

  return {
    prefix: input.prefix,
    expectedOriginAsn: input.expectedOriginAsn ?? null,
    currentOrigins: [],
    activeHijacks: [],
    historicalHijacks: [],
    riskLevel: "info",
    recommendations: [
      "Create ROAs for all your prefixes to enable RPKI-based hijack protection",
      "Monitor BGP announcements in real-time for early hijack detection",
      "Register ASPA objects to protect against route leaks",
    ],
  };
}

/**
 * Detect route leaks using ASPA validation.
 *
 * Analyzes BGP paths for ASPA validation failures, which indicate
 * potential route leaks where a customer or peer re-announces routes
 * to unauthorized neighbors.
 *
 * ASPA (Autonomous System Provider Authorization) objects declare which
 * ASes are authorized providers. A path that violates these declarations
 * indicates a route leak.
 *
 * @param input - Validated detection parameters
 * @returns Route leak detection result with ASPA analysis
 *
 * @example
 * ```
 * > Detect route leaks using ASPA validation for prefixes of AS13335
 *
 * Returns: Prefixes with ASPA-invalid paths, the leaking AS, severity,
 * and recommendations for deploying ASPA objects.
 * ```
 */
export async function handleRouteLeakDetection(
  input: z.infer<typeof routeLeakDetectionSchema>
): Promise<RouteLeakDetectionResult> {
  // TODO: Get all announced prefixes for the ASN (or use provided list)
  // TODO: For each prefix, query bgproutes.io RIB entries with ASPA validation
  // TODO: Filter for entries where aspaValidation.state === "invalid"
  // TODO: Identify the leaking AS (the hop that violates ASPA)
  // TODO: Query historical updates for past leak events
  // TODO: Check if the ASN has registered ASPA objects

  const _input = input;

  return {
    asn: 0, // TODO: parseASN(input.asn)
    name: "",
    prefixesChecked: 0,
    activeLeaks: [],
    historicalLeaks: [],
    aspaStatus: {
      hasAspaObjects: false,
      aspaObjectCount: 0,
      coveragePercent: 0,
    },
    riskLevel: "info",
    recommendations: [
      "Register ASPA objects to declare your authorized upstream providers",
      "Monitor ASPA validation results for your prefixes in real-time",
      "Coordinate with your upstreams to ensure they also deploy ASPA",
      "Use bgproutes.io real-time stream for immediate leak alerting",
    ],
  };
}

/**
 * Check for bogon prefixes and bogon ASNs in routing.
 *
 * @param input - Validated check parameters
 * @returns Bogon check result with findings
 */
export async function handleBogonCheck(
  input: z.infer<typeof bogonCheckSchema>
): Promise<BogonCheckResult> {
  // TODO: Get all announced prefixes for the ASN
  // TODO: Check against IANA reserved/special-purpose ranges
  // TODO: Check AS paths for bogon ASNs (reserved, documentation, private)
  // TODO: Check for unallocated prefixes from RIR data

  const _input = input;

  return {
    asn: 0,
    findings: [],
    bogonPrefixCount: 0,
    bogonAsnInPathCount: 0,
    clean: true,
    recommendations: [],
  };
}

/**
 * Check a resource against known blacklists and reputation databases.
 *
 * @param input - Validated check parameters
 * @returns Blacklist check result with listings
 */
export async function handleBlacklistCheck(
  input: z.infer<typeof blacklistCheckSchema>
): Promise<BlacklistCheckResult> {
  // TODO: Check against Spamhaus (DROP, EDROP, ASN-DROP)
  // TODO: Check against Team Cymru bogon lists
  // TODO: Check against various DNSBL services
  // TODO: Aggregate results from specified or all lists

  return {
    resource: input.resource,
    listed: false,
    listings: [],
    clean: true,
  };
}
