#!/usr/bin/env node
/**
 * XZBT 0.1 Structural & Semantic Exhibit Validator
 * No external dependencies. Conforms to XZBT Format Specification 0.1 (Revision 0.4).
 * Audio subsystem checks (sections 14-15) delegate to the shared runtime module so the tool
 * and the runtime can never diverge.
 */

import { readFileSync } from 'node:fs';
import { resolve } from 'node:path';
import { validateAudioSubsystem } from '../src/runtime/audio-graph.js';

const ID_REGEX = /^[a-z][a-z0-9_-]*$/;
const REF_PATH_REGEX = /^[a-z][a-z0-9_-]*(\.[a-z][a-z0-9_-]*)+$/;
const DURATION_REGEX = /^([0-9]+(?:\.[0-9]+)?)(ms|s|m|h)$/;

const RUNTIME_SIGNAL_TYPES = new Map([
  ['signals.time.elapsed', 'number'],
  ['signals.time.delta', 'number'],
  ['signals.audio.low', 'number'],
  ['signals.audio.mid', 'number'],
  ['signals.audio.high', 'number'],
  ['signals.audio.energy', 'number'],
  ['signals.pointer.x', 'number'],
  ['signals.pointer.y', 'number'],
  ['signals.viewport.width', 'number'],
  ['signals.viewport.height', 'number'],
  ['signals.scenario.active', 'boolean']
]);

const ALLOWED_ROOT_KEYS = new Set([
  'xzbt',
  'meta',
  'runtime',
  'parameters',
  'state',
  'signals',
  'ui',
  'components',
  'visuals',
  'audio',
  'sounds',
  'cadence',
  'modulators',
  'bindings',
  'events',
  'scenarios'
]);

const ALLOWED_META_KEYS = new Set([
  'id',
  'name',
  'version',
  'author',
  'description',
  'license',
  'tags'
]);

const ALLOWED_PARAM_KEYS = new Set([
  'type',
  'default',
  'min',
  'max',
  'step',
  'values',
  'label',
  'unit'
]);

const ALLOWED_STATE_KEYS = new Set([
  'type',
  'initial',
  'min',
  'max'
]);

const ALLOWED_BINDING_KEYS = new Set([
  'source',
  'target',
  'scale',
  'offset',
  'clamp',
  'smoothing',
  'when'
]);

const OPERATOR_ARITY = {
  abs: 1,
  negate: 1,
  round: 1,
  floor: 1,
  ceil: 1,
  add: 2,
  subtract: 2,
  multiply: 2,
  divide: 2,
  min: 2,
  max: 2,
  clamp: 3,
  lerp: 3
};

const COMPARISON_OPS = new Set(['eq', 'ne', 'gt', 'gte', 'lt', 'lte']);

export class ExhibitValidator {
  constructor(doc, filename = 'document.xzbt') {
    this.doc = doc;
    this.filename = filename;
    this.errors = [];
    this.warnings = [];
  }

  addError(code, path, message) {
    this.errors.push({ code, path, message });
  }

  validate() {
    if (typeof this.doc !== 'object' || this.doc === null || Array.isArray(this.doc)) {
      this.addError('ERR_SCHEMA_VALIDATION', '$', 'Top-level document must be a JSON object.');
      return this.getResult();
    }

    // 1. Format Version
    if (this.doc.xzbt !== '0.1') {
      this.addError(
        'ERR_UNSUPPORTED_VERSION',
        '$.xzbt',
        `Unsupported XZBT format version: '${this.doc.xzbt}'. Expected '0.1'.`
      );
    }

    // 2. Unknown Root Keys
    for (const key of Object.keys(this.doc)) {
      if (!ALLOWED_ROOT_KEYS.has(key)) {
        this.addError(
          'ERR_UNKNOWN_FIELD',
          `$.${key}`,
          `Unrecognized top-level field: '${key}'.`
        );
      }
    }

    // 3. Metadata
    this.validateMeta();

    // 4. Parameters
    this.validateParameters();

    // 5. State
    this.validateState();

    // 6. Bindings & Cycle Detection
    this.validateBindings();

    // 7. Audio subsystem (Format Specification sections 14-15)
    validateAudioSubsystem(this.doc, this.errors, {
      validateValueSpec: (unusedDocument, spec, path, unusedErrors, scope) => this.validateValueSpec(spec, path, scope),
      pushError: (errors, code, path, message) => errors.push({ code, path, message })
    });

    return this.getResult();
  }

  validateMeta() {
    if (!this.doc.meta || typeof this.doc.meta !== 'object' || Array.isArray(this.doc.meta)) {
      this.addError('ERR_SCHEMA_VALIDATION', '$.meta', 'Missing or invalid required object: meta.');
      return;
    }

    for (const key of Object.keys(this.doc.meta)) {
      if (!ALLOWED_META_KEYS.has(key)) {
        this.addError('ERR_UNKNOWN_FIELD', `$.meta.${key}`, `Unrecognized field in meta: '${key}'.`);
      }
    }

    const { id, name } = this.doc.meta;
    if (typeof id !== 'string' || !ID_REGEX.test(id)) {
      this.addError(
        'ERR_INVALID_ID',
        '$.meta.id',
        `Exhibit id must match ^[a-z][a-z0-9_-]*$: got '${id}'.`
      );
    } else if (id.length > 64) {
      this.addError('ERR_INVALID_ID', '$.meta.id', 'Exhibit id exceeds 64 characters limit.');
    }

    if (typeof name !== 'string' || name.trim().length === 0) {
      this.addError('ERR_SCHEMA_VALIDATION', '$.meta.name', 'Exhibit meta.name must be a non-empty string.');
    }
  }

  validateParameters() {
    if (!this.doc.parameters) return;
    if (typeof this.doc.parameters !== 'object' || Array.isArray(this.doc.parameters)) {
      this.addError('ERR_SCHEMA_VALIDATION', '$.parameters', 'parameters must be an object.');
      return;
    }

    for (const [id, spec] of Object.entries(this.doc.parameters)) {
      const path = `$.parameters.${id}`;
      if (!ID_REGEX.test(id)) {
        this.addError('ERR_INVALID_ID', path, `Parameter ID '${id}' must match ^[a-z][a-z0-9_-]*$.`);
      }
      if (typeof spec !== 'object' || spec === null || Array.isArray(spec)) {
        this.addError('ERR_SCHEMA_VALIDATION', path, 'ParameterSpec must be an object.');
        continue;
      }

      for (const key of Object.keys(spec)) {
        if (!ALLOWED_PARAM_KEYS.has(key)) {
          this.addError('ERR_UNKNOWN_FIELD', `${path}.${key}`, `Unrecognized field in ParameterSpec: '${key}'.`);
        }
      }

      const validTypes = ['number', 'integer', 'boolean', 'string', 'color', 'enum'];
      if (!validTypes.includes(spec.type)) {
        this.addError('ERR_TYPE_MISMATCH', `${path}.type`, `Invalid parameter type: '${spec.type}'.`);
      }

      if (spec.default === undefined) {
        this.addError('ERR_SCHEMA_VALIDATION', `${path}.default`, `Missing required field: default.`);
      } else {
        this.checkTypeMatches(spec.type, spec.default, `${path}.default`);
      }

      if (spec.type === 'number' || spec.type === 'integer') {
        if (spec.min !== undefined && spec.max !== undefined && spec.min > spec.max) {
          this.addError('ERR_OUT_OF_BOUNDS', `${path}.min`, `min (${spec.min}) cannot be greater than max (${spec.max}).`);
        }
        if (typeof spec.default === 'number') {
          if (spec.min !== undefined && spec.default < spec.min) {
            this.addError('ERR_OUT_OF_BOUNDS', `${path}.default`, `default (${spec.default}) is less than min (${spec.min}).`);
          }
          if (spec.max !== undefined && spec.default > spec.max) {
            this.addError('ERR_OUT_OF_BOUNDS', `${path}.default`, `default (${spec.default}) is greater than max (${spec.max}).`);
          }
        }
      }

      if (spec.type === 'enum') {
        if (!Array.isArray(spec.values) || spec.values.length === 0) {
          this.addError('ERR_SCHEMA_VALIDATION', `${path}.values`, `Enum parameter must define a non-empty values array.`);
        } else if (!spec.values.includes(spec.default)) {
          this.addError('ERR_OUT_OF_BOUNDS', `${path}.default`, `Enum default '${spec.default}' is not in values list.`);
        }
      }
    }
  }

  validateState() {
    if (!this.doc.state) return;
    if (typeof this.doc.state !== 'object' || Array.isArray(this.doc.state)) {
      this.addError('ERR_SCHEMA_VALIDATION', '$.state', 'state must be an object.');
      return;
    }

    for (const [id, spec] of Object.entries(this.doc.state)) {
      const path = `$.state.${id}`;
      if (!ID_REGEX.test(id)) {
        this.addError('ERR_INVALID_ID', path, `State ID '${id}' must match ^[a-z][a-z0-9_-]*$.`);
      }
      if (typeof spec !== 'object' || spec === null || Array.isArray(spec)) {
        this.addError('ERR_SCHEMA_VALIDATION', path, 'StateSpec must be an object.');
        continue;
      }

      for (const key of Object.keys(spec)) {
        if (!ALLOWED_STATE_KEYS.has(key)) {
          this.addError('ERR_UNKNOWN_FIELD', `${path}.${key}`, `Unrecognized field in StateSpec: '${key}'.`);
        }
      }

      const validTypes = ['number', 'integer', 'boolean', 'string'];
      if (!validTypes.includes(spec.type)) {
        this.addError('ERR_TYPE_MISMATCH', `${path}.type`, `Invalid state type: '${spec.type}'.`);
      }

      if (spec.initial === undefined) {
        this.addError('ERR_SCHEMA_VALIDATION', `${path}.initial`, `Missing required field: initial.`);
      } else {
        this.checkTypeMatches(spec.type, spec.initial, `${path}.initial`);
      }
    }
  }

  validateValueSpec(valueSpec, path, scope = null) {
    if (typeof valueSpec === 'number') {
      if (!Number.isFinite(valueSpec)) {
        this.addError('ERR_TYPE_MISMATCH', path, `Number must be finite; got ${valueSpec}.`);
      }
      return;
    }
    if (typeof valueSpec === 'boolean' || typeof valueSpec === 'string') {
      return;
    }
    if (typeof valueSpec !== 'object' || valueSpec === null || Array.isArray(valueSpec)) {
      this.addError('ERR_SCHEMA_VALIDATION', path, `Invalid ValueSpec format.`);
      return;
    }

    // Reference
    if ('ref' in valueSpec) {
      if (typeof valueSpec.ref !== 'string' || !REF_PATH_REGEX.test(valueSpec.ref)) {
        this.addError('ERR_INVALID_REFERENCE', `${path}.ref`, `Invalid reference path: '${valueSpec.ref}'.`);
      } else if (valueSpec.ref.startsWith('inputs.')) {
        // Component-graph-scoped namespace (Format Specification 15.15).
        const name = valueSpec.ref.slice('inputs.'.length);
        if (!scope?.componentParameters?.has(name)) {
          this.addError('ERR_INVALID_REFERENCE', `${path}.ref`, `Component input '${name}' is not declared here.`);
        }
      } else {
        this.resolveReference(valueSpec.ref, `${path}.ref`);
      }
      return;
    }

    // Random Range
    if ('random' in valueSpec) {
      const { random } = valueSpec;
      if (typeof random !== 'object' || random === null) {
        this.addError('ERR_SCHEMA_VALIDATION', `${path}.random`, 'random must be an object.');
        return;
      }
      if (typeof random.min !== 'number' || typeof random.max !== 'number') {
        this.addError('ERR_SCHEMA_VALIDATION', `${path}.random`, 'random requires finite numeric min and max.');
      } else if (random.min > random.max) {
        this.addError('ERR_OUT_OF_BOUNDS', `${path}.random`, `random min (${random.min}) cannot exceed max (${random.max}).`);
      }
      return;
    }

    // Weighted Choice
    if ('choose' in valueSpec) {
      if (!Array.isArray(valueSpec.choose) || valueSpec.choose.length === 0) {
        this.addError('ERR_SCHEMA_VALIDATION', `${path}.choose`, 'choose must be a non-empty array.');
        return;
      }
      for (let i = 0; i < valueSpec.choose.length; i++) {
        const item = valueSpec.choose[i];
        if (typeof item !== 'object' || item === null || item.value === undefined || typeof item.weight !== 'number' || item.weight <= 0) {
          this.addError('ERR_SCHEMA_VALIDATION', `${path}.choose[${i}]`, 'choose item requires value and weight > 0.');
        } else {
          this.validateValueSpec(item.value, `${path}.choose[${i}].value`, scope);
        }
      }
      return;
    }

    // Calculation Operator
    if ('op' in valueSpec) {
      const { op, args } = valueSpec;
      if (!OPERATOR_ARITY[op]) {
        this.addError('ERR_INVALID_OPERATOR', `${path}.op`, `Unrecognized operator: '${op}'.`);
        return;
      }
      const expectedArity = OPERATOR_ARITY[op];
      if (!Array.isArray(args)) {
        this.addError('ERR_SCHEMA_VALIDATION', `${path}.args`, `args must be an array for op '${op}'.`);
        return;
      }
      if (args.length !== expectedArity) {
        this.addError(
          'ERR_INVALID_ARITY',
          `${path}.args`,
          `Operator '${op}' requires exactly ${expectedArity} argument(s); got ${args.length}.`
        );
      }
      args.forEach((arg, index) => {
        this.validateValueSpec(arg, `${path}.args[${index}]`, scope);
      });
      return;
    }

    this.addError('ERR_SCHEMA_VALIDATION', path, `Unrecognized ValueSpec structure.`);
  }

  validateConditionSpec(cond, path) {
    if (typeof cond !== 'object' || cond === null || Array.isArray(cond)) {
      this.addError('ERR_SCHEMA_VALIDATION', path, 'ConditionSpec must be an object.');
      return;
    }

    if ('op' in cond) {
      if (!COMPARISON_OPS.has(cond.op)) {
        this.addError('ERR_INVALID_OPERATOR', `${path}.op`, `Invalid comparison operator: '${cond.op}'.`);
      }
      if (cond.left === undefined || cond.right === undefined) {
        this.addError('ERR_SCHEMA_VALIDATION', path, `Comparison condition requires 'left' and 'right'.`);
      } else {
        this.validateValueSpec(cond.left, `${path}.left`);
        this.validateValueSpec(cond.right, `${path}.right`);
      }
      return;
    }

    if ('and' in cond) {
      if (!Array.isArray(cond.and) || cond.and.length === 0) {
        this.addError('ERR_SCHEMA_VALIDATION', `${path}.and`, `'and' condition requires non-empty array.`);
      } else {
        cond.and.forEach((c, idx) => this.validateConditionSpec(c, `${path}.and[${idx}]`));
      }
      return;
    }

    if ('or' in cond) {
      if (!Array.isArray(cond.or) || cond.or.length === 0) {
        this.addError('ERR_SCHEMA_VALIDATION', `${path}.or`, `'or' condition requires non-empty array.`);
      } else {
        cond.or.forEach((c, idx) => this.validateConditionSpec(c, `${path}.or[${idx}]`));
      }
      return;
    }

    if ('not' in cond) {
      this.validateConditionSpec(cond.not, `${path}.not`);
      return;
    }

    this.addError('ERR_SCHEMA_VALIDATION', path, `Unrecognized ConditionSpec structure.`);
  }

  validateBindings() {
    if (!this.doc.bindings) return;
    if (!Array.isArray(this.doc.bindings)) {
      this.addError('ERR_SCHEMA_VALIDATION', '$.bindings', 'bindings must be an array.');
      return;
    }

    const graph = new Map(); // target -> [sources]
    const targetWriters = new Map();

    this.doc.bindings.forEach((binding, idx) => {
      const path = `$.bindings[${idx}]`;
      if (typeof binding !== 'object' || binding === null || Array.isArray(binding)) {
        this.addError('ERR_SCHEMA_VALIDATION', path, 'Binding must be an object.');
        return;
      }

      for (const key of Object.keys(binding)) {
        if (!ALLOWED_BINDING_KEYS.has(key)) {
          this.addError('ERR_UNKNOWN_FIELD', `${path}.${key}`, `Unrecognized field in BindingSpec: '${key}'.`);
        }
      }

      if (typeof binding.source !== 'string' || !REF_PATH_REGEX.test(binding.source)) {
        this.addError('ERR_INVALID_REFERENCE', `${path}.source`, `Invalid source reference: '${binding.source}'.`);
      } else {
        this.resolveReference(binding.source, `${path}.source`);
      }

      if (typeof binding.target !== 'string' || !REF_PATH_REGEX.test(binding.target)) {
        this.addError('ERR_INVALID_REFERENCE', `${path}.target`, `Invalid target reference: '${binding.target}'.`);
      } else {
        this.validateBindingTarget(binding.target, `${path}.target`);
      }

      if (binding.scale !== undefined && (typeof binding.scale !== 'number' || !Number.isFinite(binding.scale))) {
        this.addError('ERR_TYPE_MISMATCH', `${path}.scale`, 'Binding scale must be a finite number.');
      }

      if (binding.offset !== undefined && (typeof binding.offset !== 'number' || !Number.isFinite(binding.offset))) {
        this.addError('ERR_TYPE_MISMATCH', `${path}.offset`, 'Binding offset must be a finite number.');
      }

      if (binding.clamp !== undefined) {
        if (
          !Array.isArray(binding.clamp) ||
          binding.clamp.length !== 2 ||
          !binding.clamp.every((value) => typeof value === 'number' && Number.isFinite(value))
        ) {
          this.addError('ERR_SCHEMA_VALIDATION', `${path}.clamp`, 'Binding clamp must be two finite numbers.');
        } else if (binding.clamp[0] > binding.clamp[1]) {
          this.addError('ERR_OUT_OF_BOUNDS', `${path}.clamp`, 'Binding clamp minimum cannot exceed maximum.');
        }
      }

      if (binding.smoothing !== undefined) {
        if (typeof binding.smoothing !== 'string' || !DURATION_REGEX.test(binding.smoothing)) {
          this.addError('ERR_INVALID_DURATION', `${path}.smoothing`, `Invalid duration: '${binding.smoothing}'.`);
        }
      }

      if (binding.when !== undefined) {
        this.validateConditionSpec(binding.when, `${path}.when`);
      }

      const sourceType = this.getReferenceType(binding.source);
      const targetType = this.getReferenceType(binding.target);
      if (sourceType && targetType) {
        const usesNumericTransform =
          binding.scale !== undefined || binding.offset !== undefined || binding.clamp !== undefined ||
          (binding.smoothing !== undefined && binding.smoothing !== '0ms');
        const sourceNumeric = sourceType === 'number' || sourceType === 'integer';
        const targetNumeric = targetType === 'number' || targetType === 'integer';
        if (usesNumericTransform && (!sourceNumeric || !targetNumeric)) {
          this.addError('ERR_TYPE_MISMATCH', path, 'Binding transforms and smoothing require numeric source and target types.');
        } else if (!usesNumericTransform && sourceType !== targetType && !(sourceNumeric && targetNumeric)) {
          this.addError('ERR_TYPE_MISMATCH', path, `Binding source type '${sourceType}' does not match target type '${targetType}'.`);
        }
      }

      if (typeof binding.source === 'string' && typeof binding.target === 'string') {
        if (!graph.has(binding.target)) graph.set(binding.target, []);
        graph.get(binding.target).push(binding.source);

        const priorWriter = targetWriters.get(binding.target);
        if (priorWriter !== undefined) {
          this.addError(
            'ERR_CONFLICTING_BINDING',
            `${path}.target`,
            `Binding target '${binding.target}' is already written by $.bindings[${priorWriter}].`
          );
        } else {
          targetWriters.set(binding.target, idx);
        }
      }
    });

    // Cycle detection using DFS
    const visited = new Set();
    const visiting = new Set();

    const checkCycle = (node, chain) => {
      if (visiting.has(node)) {
        this.addError(
          'ERR_CYCLIC_DEPENDENCY',
          '$.bindings',
          `Dependency cycle detected: ${chain.concat(node).join(' -> ')}`
        );
        return;
      }
      if (visited.has(node)) return;

      visiting.add(node);
      const dependencies = graph.get(node) || [];
      for (const dep of dependencies) {
        checkCycle(dep, chain.concat(node));
      }
      visiting.delete(node);
      visited.add(node);
    };

    for (const node of graph.keys()) {
      if (!visited.has(node)) {
        checkCycle(node, []);
      }
    }
  }

  validateBindingTarget(refPath, location) {
    const parts = refPath.split('.');
    const namespace = parts[0];

    if (namespace === 'parameters' || namespace === 'state') {
      if (parts.length !== 2) {
        this.addError('ERR_UNSUPPORTED_TARGET', location, `Target '${refPath}' is not a scalar ${namespace} target.`);
        return;
      }
      this.resolveReference(refPath, location);
      return;
    }

    if (namespace === 'audio' && parts.length === 4 && parts[1] === 'buses' && parts[3] === 'gain') {
      const busId = parts[2];
      if (!this.doc.audio?.buses?.[busId]) {
        this.addError('ERR_INVALID_REFERENCE', location, `Target '${refPath}' refers to a missing audio bus '${busId}'.`);
      }
      return;
    }

    this.addError('ERR_UNSUPPORTED_TARGET', location, `Target '${refPath}' is not exposed by the shared 0.1 target registry.`);
  }

  getReferenceType(refPath) {
    if (typeof refPath !== 'string') return null;
    const parts = refPath.split('.');
    if (parts[0] === 'parameters' && parts.length === 2) return this.doc.parameters?.[parts[1]]?.type || null;
    if (parts[0] === 'state' && parts.length === 2) return this.doc.state?.[parts[1]]?.type || null;
    if (parts[0] === 'audio' && parts[1] === 'buses' && parts[3] === 'gain') return 'number';
    if (parts[0] === 'signals') return RUNTIME_SIGNAL_TYPES.get(refPath) || null;
    if (parts[0] === 'modulators') return 'number';
    return null;
  }

  resolveReference(refPath, location) {
    const parts = refPath.split('.');
    const namespace = parts[0];

    if (namespace === 'parameters') {
      const paramId = parts[1];
      if (!this.doc.parameters || !this.doc.parameters[paramId]) {
        this.addError(
          'ERR_INVALID_REFERENCE',
          location,
          `Reference '${refPath}' refers to non-existent parameter '${paramId}'.`
        );
      }
    } else if (namespace === 'state') {
      const stateId = parts[1];
      if (!this.doc.state || !this.doc.state[stateId]) {
        this.addError(
          'ERR_INVALID_REFERENCE',
          location,
          `Reference '${refPath}' refers to non-existent state variable '${stateId}'.`
        );
      }
    } else if (namespace === 'signals') {
      if (!RUNTIME_SIGNAL_TYPES.has(refPath)) {
        this.addError('ERR_INVALID_REFERENCE', location, `Reference '${refPath}' is not a declared 0.1 runtime signal.`);
      }
    } else if (namespace === 'modulators') {
      const modulatorId = parts[1];
      if (!this.doc.modulators || !this.doc.modulators[modulatorId]) {
        this.addError('ERR_INVALID_REFERENCE', location, `Reference '${refPath}' refers to non-existent modulator '${modulatorId}'.`);
      }
    }
  }

  checkTypeMatches(expectedType, value, path) {
    if (expectedType === 'number') {
      if (typeof value !== 'number' || !Number.isFinite(value)) {
        this.addError('ERR_TYPE_MISMATCH', path, `Expected finite number; got ${JSON.stringify(value)}.`);
      }
    } else if (expectedType === 'integer') {
      if (!Number.isInteger(value)) {
        this.addError('ERR_TYPE_MISMATCH', path, `Expected integer; got ${JSON.stringify(value)}.`);
      }
    } else if (expectedType === 'boolean') {
      if (typeof value !== 'boolean') {
        this.addError('ERR_TYPE_MISMATCH', path, `Expected boolean; got ${JSON.stringify(value)}.`);
      }
    } else if (expectedType === 'string') {
      if (typeof value !== 'string') {
        this.addError('ERR_TYPE_MISMATCH', path, `Expected string; got ${JSON.stringify(value)}.`);
      }
    } else if (expectedType === 'color') {
      if (typeof value !== 'string' || (!value.startsWith('#') && value.trim().length === 0)) {
        this.addError('ERR_TYPE_MISMATCH', path, `Expected valid color string; got ${JSON.stringify(value)}.`);
      }
    } else if (expectedType === 'enum') {
      if (typeof value !== 'string') {
        this.addError('ERR_TYPE_MISMATCH', path, `Expected enum string; got ${JSON.stringify(value)}.`);
      }
    }
  }

  getResult() {
    return {
      valid: this.errors.length === 0,
      filename: this.filename,
      errorCount: this.errors.length,
      errors: this.errors
    };
  }
}

// CLI runner
if (import.meta.url.endsWith(process.argv[1]) || process.argv[1]?.endsWith('validate-exhibit.mjs')) {
  const args = process.argv.slice(2);
  const jsonMode = args.includes('--json');
  const files = args.filter((arg) => arg !== '--json');

  if (files.length === 0) {
    console.error('Usage: node tools/validate-exhibit.mjs [--json] <path-to-exhibit.xzbt ...>');
    process.exit(2);
  }

  let allPassed = true;
  const results = [];

  for (const filePath of files) {
    try {
      const content = readFileSync(resolve(filePath), 'utf-8');
      const doc = JSON.parse(content);
      const validator = new ExhibitValidator(doc, filePath);
      const result = validator.validate();
      results.push(result);
      if (!result.valid) allPassed = false;
    } catch (err) {
      allPassed = false;
      results.push({
        valid: false,
        filename: filePath,
        errorCount: 1,
        errors: [{ code: 'ERR_SCHEMA_VALIDATION', path: '$', message: err.message }]
      });
    }
  }

  if (jsonMode) {
    console.log(JSON.stringify(results, null, 2));
  } else {
    for (const res of results) {
      if (res.valid) {
        console.log(`[PASS] ${res.filename} (0 errors)`);
      } else {
        console.error(`[FAIL] ${res.filename} (${res.errorCount} error${res.errorCount === 1 ? '' : 's'}):`);
        for (const err of res.errors) {
          console.error(`  - [${err.code}] ${err.path}: ${err.message}`);
        }
      }
    }
  }

  process.exit(allPassed ? 0 : 1);
}