import type {
  NapcatAuditClassificationInput,
  NapcatAuditClassificationResult,
  NapcatAuditCommand,
  NapcatAutomationReasonCode,
  NapcatUpstreamAuditResult,
} from './napcatAutomation.types.js';

export const napcatUpstreamHotZonePatterns = [
  'packages/napcat-core/**login*',
  'packages/napcat-core/**qrcode*',
  'packages/napcat-shell/**',
  'packages/napcat-framework/**',
  'packages/napcat-webui-backend/**QQLogin*',
  'packages/napcat-webui-backend/**Data*',
  'packages/napcat-webui-backend/**auth*',
  'packages/napcat-webui-frontend/**',
  'packages/napcat-adapter/**',
  'packages/napcat-onebot/**',
  'packages/napcat-vite/**',
  'package.json',
  'pnpm-lock.yaml',
  'tsconfig*.json',
  'vite*.ts',
] as const;

const hotZoneMatchers: Array<{ pattern: string; regex: RegExp }> = [
  {
    pattern: 'packages/napcat-core/**login*',
    regex: /^packages\/napcat-core\/.*login.*$/i,
  },
  {
    pattern: 'packages/napcat-core/**qrcode*',
    regex: /^packages\/napcat-core\/.*qrcode.*$/i,
  },
  {
    pattern: 'packages/napcat-shell/**',
    regex: /^packages\/napcat-shell(?:\/|$)/i,
  },
  {
    pattern: 'packages/napcat-framework/**',
    regex: /^packages\/napcat-framework(?:\/|$)/i,
  },
  {
    pattern: 'packages/napcat-webui-backend/**QQLogin*',
    regex: /^packages\/napcat-webui-backend\/.*qqlogin.*$/i,
  },
  {
    pattern: 'packages/napcat-webui-backend/**Data*',
    regex: /^packages\/napcat-webui-backend\/.*data.*$/i,
  },
  {
    pattern: 'packages/napcat-webui-backend/**auth*',
    regex: /^packages\/napcat-webui-backend\/.*auth.*$/i,
  },
  {
    pattern: 'packages/napcat-webui-frontend/**',
    regex: /^packages\/napcat-webui-frontend(?:\/|$)/i,
  },
  {
    pattern: 'packages/napcat-adapter/**',
    regex: /^packages\/napcat-adapter(?:\/|$)/i,
  },
  {
    pattern: 'packages/napcat-onebot/**',
    regex: /^packages\/napcat-onebot(?:\/|$)/i,
  },
  {
    pattern: 'packages/napcat-vite/**',
    regex: /^packages\/napcat-vite(?:\/|$)/i,
  },
  { pattern: 'package.json', regex: /^package\.json$/i },
  { pattern: 'pnpm-lock.yaml', regex: /^pnpm-lock\.yaml$/i },
  { pattern: 'tsconfig*.json', regex: /(?:^|\/)tsconfig[^/]*\.json$/i },
  { pattern: 'vite*.ts', regex: /(?:^|\/)vite[^/]*\.ts$/i },
];

/**
 * Checks whether Git audit metadata contains a repo-relative path that the classifier can trust.
 * @param value - Raw path string from fork/upstream Git diff collectors; empty entries are allowed because collectors may emit blank lines.
 * @returns True when a non-empty path is absolute, UNC-based, or contains a parent-directory segment.
 */
function hasInvalidAuditPath(value: string): boolean {
  const trimmed = value.trim();
  if (!trimmed) return false;
  if (/^[a-zA-Z]:/.test(trimmed)) return true;
  if (trimmed.startsWith('\\\\') || trimmed.startsWith('//')) return true;
  if (trimmed.startsWith('\\') || trimmed.startsWith('/')) return true;

  const normalized = trimmed
    .replace(/\\/g, '/')
    .replace(/^\.\/+/, '')
    .replace(/\/+/g, '/');
  return normalized.split('/').includes('..');
}

/**
 * Checks both file lists for invalid non repo-relative metadata.
 * @param input - Collector result carrying fork patch and upstream changed file paths; both arrays must contain repo-relative Git paths when non-empty.
 * @returns True when any path entry would make deterministic hot-zone and overlap classification untrustworthy.
 */
function hasInvalidAuditMetadata(
  input: NapcatAuditClassificationInput,
): boolean {
  for (const file of input.forkPatchFiles) {
    if (hasInvalidAuditPath(file)) {
      return true;
    }
  }
  for (const file of input.upstreamChangedFiles) {
    if (hasInvalidAuditPath(file)) {
      return true;
    }
  }
  return false;
}

/**
 * Normalizes Git path output into a stable comparison key for audit classifiers.
 * @param value - File path from Git diff/status collectors; may contain Windows separators, leading `./`, or surrounding whitespace, but must represent a repo-relative path.
 * @returns A lowercase POSIX-style path key used only for deterministic classification.
 */
function normalizeAuditPath(value: string): string {
  return value
    .trim()
    .replace(/\\/g, '/')
    .replace(/^\.\/+/, '')
    .replace(/\/+/g, '/')
    .toLowerCase();
}

/**
 * Normalizes and de-duplicates path lists while preserving first-seen order.
 * @param files - File paths reported by fork patch and upstream release diff collectors; empty or whitespace-only entries are ignored.
 * @returns Stable repo-relative path keys for hot-zone and overlap checks.
 */
function normalizeAuditPathList(files: string[]): string[] {
  const normalized: string[] = [];
  const seen = new Set<string>();

  for (const file of files) {
    const pathKey = normalizeAuditPath(file);
    if (!pathKey || seen.has(pathKey)) continue;
    seen.add(pathKey);
    normalized.push(pathKey);
  }

  return normalized;
}

/**
 * Checks whether a normalized path falls inside the NapCat upstream manual-review hot zones.
 * @param pathKey - Lowercase POSIX path from `normalizeAuditPathList`; must be repo-relative and not an absolute filesystem path.
 * @returns True when the path is covered by one of the fixed hot-zone patterns from the release plan.
 */
function isNapcatHotZonePath(pathKey: string): boolean {
  for (const matcher of hotZoneMatchers) {
    if (matcher.regex.test(pathKey)) {
      return true;
    }
  }
  return false;
}

/**
 * Collects upstream hot-zone file hits in deterministic first-seen order.
 * @param upstreamChangedFiles - Upstream release diff files from the last accepted base to the candidate release; values must be repo-relative Git paths.
 * @returns The subset of upstream paths that require manual human review.
 */
function collectHotZoneFiles(upstreamChangedFiles: string[]): string[] {
  const hotZoneFiles: string[] = [];

  for (const pathKey of normalizeAuditPathList(upstreamChangedFiles)) {
    if (isNapcatHotZonePath(pathKey)) {
      hotZoneFiles.push(pathKey);
    }
  }

  return hotZoneFiles;
}

/**
 * Collects exact file overlaps between KT fork patches and upstream release changes.
 * @param forkPatchFiles - Fork-only patch files collected from the KT fork comparison range; values must be repo-relative Git paths.
 * @param upstreamChangedFiles - Upstream release diff files collected from the upstream comparison range; values must be repo-relative Git paths.
 * @returns Stable exact path overlaps that require human review before candidate creation.
 */
function collectOverlapFiles(
  forkPatchFiles: string[],
  upstreamChangedFiles: string[],
): string[] {
  const upstreamChangedPathSet = new Set(
    normalizeAuditPathList(upstreamChangedFiles),
  );
  const overlapFiles: string[] = [];

  for (const pathKey of normalizeAuditPathList(forkPatchFiles)) {
    if (upstreamChangedPathSet.has(pathKey)) {
      overlapFiles.push(pathKey);
    }
  }

  return overlapFiles;
}

/**
 * Builds the public classification summary without leaking long file lists into callers.
 * @param reasonCodes - Reason codes selected by the classifier; blocked and manual-review states carry operational meaning for the next pipeline gate.
 * @param hotZoneCount - Number of upstream files matching fixed NapCat hot-zone patterns.
 * @param overlapCount - Number of exact files changed by both the KT fork patch range and upstream release range.
 * @returns A short deterministic summary suitable for MCP responses and JSON artifacts.
 */
function buildClassificationSummary(
  reasonCodes: NapcatAutomationReasonCode[],
  hotZoneCount: number,
  overlapCount: number,
): string {
  if (reasonCodes.includes('DRY_MERGE_CONFLICT')) {
    return 'Dry merge conflict detected; block automation until a human resolves the upstream sync.';
  }
  if (
    reasonCodes.includes('HOT_ZONE_CHANGED') ||
    reasonCodes.includes('FORK_PATCH_OVERLAP')
  ) {
    return `Manual review required: hotZoneFiles=${hotZoneCount}, forkPatchOverlaps=${overlapCount}.`;
  }
  return 'Safe candidate: no dry-merge conflict, hot-zone change, or fork patch overlap was detected.';
}

/**
 * Classifies a NapCat upstream sync audit from deterministic collector metadata.
 * @param input - Collector result from dry-merge probing plus fork/upstream Git diff file lists; file arrays must contain repo-relative paths from the NapCatQQ fork.
 * @returns Classification, reason codes, recommended action, and summary for the next release-pipeline gate.
 */
export function classifyNapcatUpstreamAudit(
  input: NapcatAuditClassificationInput,
): NapcatAuditClassificationResult {
  if (hasInvalidAuditMetadata(input)) {
    return {
      classification: 'blocked',
      reasonCodes: ['METADATA_UNAVAILABLE'],
      recommendedAction: 'block',
      summary:
        'Invalid audit metadata: fork and upstream file paths must be repo-relative Git paths without absolute roots, UNC prefixes, or parent-directory segments.',
    };
  }

  if (input.dryMergeConflict) {
    return {
      classification: 'blocked',
      reasonCodes: ['DRY_MERGE_CONFLICT'],
      recommendedAction: 'block',
      summary: buildClassificationSummary(['DRY_MERGE_CONFLICT'], 0, 0),
    };
  }

  const hotZoneFiles = collectHotZoneFiles(input.upstreamChangedFiles);
  const overlapFiles = collectOverlapFiles(
    input.forkPatchFiles,
    input.upstreamChangedFiles,
  );
  const reasonCodes: NapcatAutomationReasonCode[] = [];

  if (hotZoneFiles.length > 0) {
    reasonCodes.push('HOT_ZONE_CHANGED');
  }
  if (overlapFiles.length > 0) {
    reasonCodes.push('FORK_PATCH_OVERLAP');
  }
  if (reasonCodes.length > 0) {
    return {
      classification: 'manual-review',
      reasonCodes,
      recommendedAction: 'request-human-review',
      summary: buildClassificationSummary(
        reasonCodes,
        hotZoneFiles.length,
        overlapFiles.length,
      ),
    };
  }

  return {
    classification: 'safe-candidate',
    reasonCodes: ['NO_UPSTREAM_CHANGE'],
    recommendedAction: 'create-candidate-branch',
    summary: buildClassificationSummary(['NO_UPSTREAM_CHANGE'], 0, 0),
  };
}

/**
 * Builds a read-only upstream audit plan for NapCatQQ release sync automation.
 * @param input - Same deterministic classifier input supplied by the dry-run collector; values are embedded only in the returned classification, never executed.
 * @returns Dry-run commands and artifact paths for a future collector, with no Git merge/push, Docker, Kubernetes, or release mutations.
 */
export function buildNapcatUpstreamAudit(
  input: NapcatAuditClassificationInput,
): NapcatUpstreamAuditResult {
  const classification = classifyNapcatUpstreamAudit(input);
  const commands: NapcatAuditCommand[] = [
    {
      command: 'git status --short --branch',
      description: 'Confirm the fork worktree state before reading audit ranges.',
      readOnly: true,
    },
    {
      command: 'git fetch --dry-run upstream --tags --prune',
      description:
        'Probe upstream release ref availability without updating local refs.',
      readOnly: true,
    },
    {
      command: 'git fetch --dry-run origin --prune',
      description:
        'Probe fork ref availability without updating remote-tracking refs.',
      readOnly: true,
    },
    {
      command:
        'git diff --name-only "${LAST_ACCEPTED_UPSTREAM_BASE:-origin/main}..${UPSTREAM_RELEASE_REF:-upstream/main}"',
      description: 'List upstream release files changed since the last accepted base.',
      readOnly: true,
    },
    {
      command:
        'git diff --name-only "${LAST_ACCEPTED_UPSTREAM_BASE:-origin/main}..HEAD"',
      description: 'List KT fork patch files for deterministic overlap checks.',
      readOnly: true,
    },
    {
      command:
        'git merge-tree "${FORK_BRANCH:-HEAD}" "${UPSTREAM_RELEASE_REF:-upstream/main}"',
      description: 'Probe the dry merge shape without updating the worktree or refs.',
      readOnly: true,
    },
  ];

  return {
    ...classification,
    artifacts: [
      {
        path: '.kt-workspace/test-artifacts/napcat-upstream-audit/context.md',
        type: 'markdown',
      },
      {
        path: '.kt-workspace/test-artifacts/napcat-upstream-audit/classification.json',
        type: 'json',
      },
      {
        path: '.kt-workspace/test-artifacts/napcat-upstream-audit/files.json',
        type: 'json',
      },
    ],
    commands,
    execute: false,
    hotZonePatterns: [...napcatUpstreamHotZonePatterns],
  };
}