/**
 * @module mcp-server/tools/rpki
 * MCP Tool: RPKI validation and compliance monitoring.
 *
 * Validates prefix-origin pairs against ROAs, generates compliance reports,
 * and identifies networks at IXs without RPKI coverage.
 */

import { z } from "zod";
import type {
  RPKIValidation,
  RPKIComplianceReport,
} from "../../types/common.js";
import { parseASN } from "../../types/common.js";

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

/** Input schema for RPKI validation */
export const rpkiValidateSchema = z.object({
  prefix: z.string().describe("Prefix to validate (e.g., '1.1.1.0/24')"),
  origin_asn: z
    .union([z.string(), z.number()])
    .describe("Origin ASN to validate against"),
});

/** Input schema for RPKI compliance report */
export const rpkiComplianceSchema = z.object({
  asn: z
    .union([z.string(), z.number()])
    .describe("ASN to generate compliance report for"),
  include_recommendations: z
    .boolean()
    .optional()
    .default(true)
    .describe("Include AI-generated improvement recommendations"),
});

/** Input schema for IX RPKI coverage analysis */
export const rpkiIXCoverageSchema = z.object({
  ix_name: z
    .string()
    .describe("IX name to analyze (e.g., 'AMS-IX', 'DE-CIX Frankfurt')"),
  show_uncovered: z
    .boolean()
    .optional()
    .default(true)
    .describe("List ASNs without RPKI coverage"),
});

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

/**
 * Validate a prefix-origin pair against RPKI ROAs.
 *
 * @example
 * ```
 * > Is 1.1.1.0/24 from AS13335 RPKI-valid?
 *
 * Returns: Validation state, matching ROAs, and explanation.
 * ```
 */
export async function handleRPKIValidation(
  input: z.infer<typeof rpkiValidateSchema>
): Promise<RPKIValidation> {
  const originASN = parseASN(input.origin_asn);

  // TODO: Implementation steps:
  // 1. Query RPKI validator (Routinator or RIPE RPKI)
  // 2. Check for matching ROAs
  // 3. Determine validation state
  // 4. Return structured result

  return {
    prefix: input.prefix,
    originASN,
    state: "unknown", // TODO: From RPKI client
    matchingROAs: [],
    reason: "RPKI validation not yet implemented",
  };
}

/**
 * Generate RPKI compliance report for an ASN.
 *
 * Analyzes all announced prefixes for RPKI coverage and generates
 * a detailed compliance report with recommendations.
 *
 * @example
 * ```
 * > Generate an RPKI compliance report for AS13335
 *
 * Returns: Coverage percentage, uncovered prefixes, invalid ROAs,
 *          and step-by-step improvement recommendations.
 * ```
 */
export async function handleRPKICompliance(
  input: z.infer<typeof rpkiComplianceSchema>
): Promise<RPKIComplianceReport> {
  const asn = parseASN(input.asn);

  // TODO: Implementation steps:
  // 1. Get all announced prefixes from RIPE Stat
  // 2. Validate each prefix against RPKI
  // 3. Calculate coverage metrics
  // 4. If include_recommendations, use AI to generate advice
  // 5. Return comprehensive report

  return {
    asn,
    name: "", // TODO: From PeeringDB
    totalPrefixes: 0,
    validPrefixes: 0,
    invalidPrefixes: 0,
    unknownPrefixes: 0,
    coveragePercent: 0,
    recommendations: input.include_recommendations
      ? [
          "Create ROAs for all announced prefixes via your RIR portal",
          "Set max-length equal to prefix length to prevent sub-prefix hijacks",
          "Enable RPKI-invalid route filtering on all BGP sessions",
          "Monitor RPKI validation state with PeerCortex or similar tools",
        ]
      : [],
    generatedAt: new Date().toISOString(),
  };
}

/**
 * Analyze RPKI coverage at an Internet Exchange.
 *
 * Lists all participants at an IX and their RPKI deployment status.
 * Useful for peering coordinators and IX operators.
 *
 * @example
 * ```
 * > Which ASNs at AMS-IX don't have RPKI?
 *
 * Returns: List of ASNs without ROA coverage, grouped by severity.
 * ```
 */
export async function handleRPKIIXCoverage(
  input: z.infer<typeof rpkiIXCoverageSchema>
): Promise<{
  ix: string;
  totalParticipants: number;
  withRPKI: number;
  withoutRPKI: number;
  coveragePercent: number;
  uncoveredASNs?: ReadonlyArray<{
    asn: number;
    name: string;
    prefixCount: number;
  }>;
}> {
  // TODO: Implementation steps:
  // 1. Search PeeringDB for the IX
  // 2. Get all participants at the IX
  // 3. For each participant, check RPKI coverage
  // 4. Calculate aggregate statistics
  // 5. Return report with optional uncovered ASN list

  return {
    ix: input.ix_name,
    totalParticipants: 0,
    withRPKI: 0,
    withoutRPKI: 0,
    coveragePercent: 0,
    uncoveredASNs: input.show_uncovered ? [] : undefined,
  };
}
