#!/usr/bin/env node
/**
 * OpenAPI 兼容性检查（A0 回退实现）。
 *
 * 优先使用 oasdiff 二进制；未安装时使用本脚本的结构化回退检查：
 * - 删除 path / operation
 * - 删除 components.schemas
 * - 请求体必填字段新增、字段类型变更
 *
 * 基线来自 git HEAD 中的快照；首次提交（快照尚未入库）时跳过。
 */
import { execFileSync } from 'node:child_process';
import { existsSync, readFileSync } from 'node:fs';
import { resolve } from 'node:path';

const SNAPSHOT = resolve(process.cwd(), 'openapi/lingxi.openapi.json');
const HTTP_METHODS = ['get', 'post', 'put', 'patch', 'delete', 'head', 'options'];

if (!existsSync(SNAPSHOT)) {
  console.error(`未找到 OpenAPI 快照：${SNAPSHOT}，请先执行 pnpm openapi:export`);
  process.exit(1);
}

const current = JSON.parse(readFileSync(SNAPSHOT, 'utf8'));

let baseline = null;
try {
  const raw = execFileSync('git', ['show', `HEAD:${'openapi/lingxi.openapi.json'}`], {
    encoding: 'utf8',
    stdio: ['ignore', 'pipe', 'ignore'],
  });
  baseline = JSON.parse(raw);
} catch {
  console.log('基线快照尚未入库，跳过 OpenAPI diff（首次提交）。');
  process.exit(0);
}

const breaking = [];

for (const [path, baselinePath] of Object.entries(baseline.paths ?? {})) {
  const currentPath = current.paths?.[path];
  if (!currentPath) {
    breaking.push(`删除路径：${path}`);
    continue;
  }
  for (const method of HTTP_METHODS) {
    if (baselinePath[method] !== undefined && currentPath[method] === undefined) {
      breaking.push(`删除操作：${method.toUpperCase()} ${path}`);
    }
  }
}

for (const schemaName of Object.keys(baseline.components?.schemas ?? {})) {
  if (current.components?.schemas?.[schemaName] === undefined) {
    breaking.push(`删除 schema：${schemaName}`);
  }
}

const baselineSchemas = baseline.components?.schemas ?? {};
const currentSchemas = current.components?.schemas ?? {};
for (const [name, baselineSchema] of Object.entries(baselineSchemas)) {
  const currentSchema = currentSchemas[name];
  if (currentSchema === undefined) {
    continue;
  }
  const baselineRequired = new Set(baselineSchema.required ?? []);
  for (const required of currentSchema.required ?? []) {
    if (!baselineRequired.has(required)) {
      breaking.push(`schema ${name} 新增必填字段：${required}`);
    }
  }
  for (const [property, baselineProperty] of Object.entries(baselineSchema.properties ?? {})) {
    const currentProperty = currentSchema.properties?.[property];
    if (
      currentProperty !== undefined &&
      baselineProperty.type !== undefined &&
      currentProperty.type !== undefined &&
      baselineProperty.type !== currentProperty.type
    ) {
      breaking.push(
        `schema ${name}.${property} 类型变更：${baselineProperty.type} -> ${currentProperty.type}`,
      );
    }
  }
}

if (breaking.length > 0) {
  console.error('检测到破坏性 OpenAPI 变更：');
  for (const item of breaking) {
    console.error(`  - ${item}`);
  }
  process.exit(1);
}

console.log('OpenAPI 无破坏性变更。');