import ava, { type ExecutionContext } from 'ava'
import { parseSync } from 'oxc-parser'

import { createCjsBinding, createEsmBinding } from '../templates/js-binding.js'
import { createWasiBrowserBinding } from '../templates/load-wasi-template.js'
import { createWasiBrowserWorkerBinding } from '../templates/wasi-worker-template.js'

const test = ava

// Snapshot tests for full template output

test('createWasiBrowserBinding default', (t) => {
  t.snapshot(createWasiBrowserBinding('test-wasi'))
})

test('createWasiBrowserBinding with errorEvent', (t) => {
  t.snapshot(
    createWasiBrowserBinding(
      'test-wasi',
      4000,
      65536,
      false,
      false,
      false,
      true,
    ),
  )
})

test('createWasiBrowserBinding with errorEvent and fs', (t) => {
  t.snapshot(
    createWasiBrowserBinding(
      'test-wasi',
      4000,
      65536,
      true,
      false,
      false,
      true,
    ),
  )
})

test('createWasiBrowserWorkerBinding default', (t) => {
  t.snapshot(createWasiBrowserWorkerBinding(false, false))
})

test('createWasiBrowserWorkerBinding with errorEvent', (t) => {
  t.snapshot(createWasiBrowserWorkerBinding(false, true))
})

test('createWasiBrowserWorkerBinding with errorEvent and fs', (t) => {
  t.snapshot(createWasiBrowserWorkerBinding(true, true))
})

function assertValidJS(t: ExecutionContext, code: string, label: string) {
  const { errors } = parseSync('test.mjs', code, { sourceType: 'module' })
  t.deepEqual(
    errors,
    [],
    `${label}: generated code should have no syntax errors`,
  )
}

const browserBindingCases: Array<{
  name: string
  args: Parameters<typeof createWasiBrowserBinding>
}> = [
  { name: 'default', args: ['test'] },
  { name: 'fs', args: ['test', 4000, 65536, true] },
  { name: 'asyncInit', args: ['test', 4000, 65536, false, true] },
  { name: 'buffer', args: ['test', 4000, 65536, false, false, true] },
  {
    name: 'errorEvent',
    args: ['test', 4000, 65536, false, false, false, true],
  },
  {
    name: 'fs + errorEvent',
    args: ['test', 4000, 65536, true, false, false, true],
  },
  { name: 'fs + buffer', args: ['test', 4000, 65536, true, false, true] },
  {
    name: 'fs + buffer + errorEvent',
    args: ['test', 4000, 65536, true, false, true, true],
  },
  {
    name: 'asyncInit + errorEvent',
    args: ['test', 4000, 65536, false, true, false, true],
  },
  { name: 'all options', args: ['test', 4000, 65536, true, true, true, true] },
]

for (const { name, args } of browserBindingCases) {
  test(`createWasiBrowserBinding syntax valid: ${name}`, (t) => {
    assertValidJS(t, createWasiBrowserBinding(...args), name)
  })
}

const workerBindingCases: Array<{
  name: string
  args: Parameters<typeof createWasiBrowserWorkerBinding>
}> = [
  { name: 'default', args: [false, false] },
  { name: 'fs', args: [true, false] },
  { name: 'errorEvent', args: [false, true] },
  { name: 'fs + errorEvent', args: [true, true] },
]

for (const { name, args } of workerBindingCases) {
  test(`createWasiBrowserWorkerBinding syntax valid: ${name}`, (t) => {
    assertValidJS(t, createWasiBrowserWorkerBinding(...args), name)
  })
}

// The CJS binding loader ships inside published packages whose `engines`
// can declare support for old Node versions (e.g. `>= 10`). It must therefore
// avoid syntax/APIs newer than what those runtimes support:
//   - `require('node:*')` — the `node:` scheme in CommonJS `require()` is only
//     available on Node >= 14.18 / 16.
//   - optional chaining (`?.`) and nullish coalescing (`??`) — Node >= 14.
//   - the `new Error(message, { cause })` options form — Node < 16.9 ignores
//     the second argument, dropping the load-error chain; assign
//     `error.cause` instead.
const cjsBindingCases: Array<{ name: string; code: string }> = [
  {
    name: 'default',
    code: createCjsBinding('test', '@scope/test', ['sum', 'sub']),
  },
  {
    name: 'with version check',
    code: createCjsBinding('test', '@scope/test', ['sum', 'sub'], '1.0.0'),
  },
]

// Matches a `node:` builtin scheme in either a `require('node:fs')` or an
// `import ... from 'node:module'` specifier.
const NODE_SCHEME_RE = /['"]node:/

for (const { name, code } of cjsBindingCases) {
  test(`createCjsBinding is Node 12 compatible: ${name}`, (t) => {
    assertValidJS(t, code, name)
    t.false(
      NODE_SCHEME_RE.test(code),
      'CJS loader must not use the node: scheme (unsupported on Node < 14.18/16 for require())',
    )
    t.false(code.includes('?.'), 'CJS loader must not use optional chaining')
    t.false(code.includes('??'), 'CJS loader must not use nullish coalescing')
    t.false(
      /\bcause:/.test(code),
      'CJS loader must not pass `{ cause }` to the Error constructor (ignored on Node < 16.9); assign `error.cause` instead',
    )
  })
}

test('createEsmBinding is Node 12 compatible', (t) => {
  const code = createEsmBinding('test', '@scope/test', ['sum'])
  assertValidJS(t, code, 'esm')
  t.false(
    NODE_SCHEME_RE.test(code),
    'ESM loader must not use the node: scheme (incl. `import ... from "node:module"`)',
  )
  t.false(code.includes('?.'), 'ESM loader must not use optional chaining')
  t.false(code.includes('??'), 'ESM loader must not use nullish coalescing')
})