/* eslint-disable @typescript-eslint/explicit-function-return-type */
import { readFile, writeFile } from 'node:fs/promises'
import { resolve } from 'node:path'
import { format } from 'prettier'
import ts from 'typescript'

const root = resolve(import.meta.dirname, '..')
const catalogPath = resolve(root, 'src/shared/renderer-contract-catalog.ts')
const outputPath = resolve(root, 'src/shared/web-api-map.generated.ts')

const sourceText = await readFile(catalogPath, 'utf8')
const source = ts.createSourceFile(catalogPath, sourceText, ts.ScriptTarget.Latest, true)

const stringLiteral = (node, label) => {
  if (ts.isStringLiteral(node) || ts.isNoSubstitutionTemplateLiteral(node)) return node.text
  if (ts.isIdentifier(node)) return node.text
  throw new Error(`Renderer contract ${label} must be a string literal.`)
}

// prettier-ignore
const invokeProfiles = new Set(['WEB', 'LOCAL', 'MAPPED_ELECTRON', 'MAPPED_NATIVE', 'DELEGATED_NATIVE'])
const eventProfiles = new Set(['EVENT'])
// prettier-ignore
const unprojectedProfiles = new Set(['ELECTRON', 'SEND', 'WINDOW_FIND_READY', 'ELECTRON_EVENT', 'CLOSE_PANE_EVENT', 'NATIVE'])

const projectionFor = (node) => {
  if (!node) return 'invoke'
  if (!ts.isIdentifier(node)) throw new Error('Renderer contract profile must be an identifier.')
  if (invokeProfiles.has(node.text)) return 'invoke'
  if (eventProfiles.has(node.text)) return 'event'
  if (unprojectedProfiles.has(node.text)) return 'none'
  throw new Error(`Unknown renderer contract profile: ${node.text}`)
}

const invoke = {}
const events = {}

let contract
const findCatalog = (node) => {
  const argument =
    ts.isVariableDeclaration(node) &&
    node.initializer &&
    ts.isCallExpression(node.initializer) &&
    node.initializer.arguments[0]
      ? node.initializer.arguments[0]
      : undefined
  const value = argument && ts.isAsExpression(argument) ? argument.expression : argument
  if (
    ts.isVariableDeclaration(node) &&
    ts.isIdentifier(node.name) &&
    node.name.text === 'RENDERER_API_CONTRACT' &&
    value &&
    ts.isObjectLiteralExpression(value)
  ) {
    contract = value
  }
  ts.forEachChild(node, findCatalog)
}
findCatalog(source)
if (!contract) throw new Error('Typed renderer contract was not found.')

for (const property of contract.properties) {
  if (!ts.isPropertyAssignment(property)) {
    throw new Error('Renderer contract may only contain property assignments.')
  }
  const path = stringLiteral(property.name, 'public path')
  const initializer = property.initializer
  if (
    !ts.isCallExpression(initializer) ||
    !ts.isCallExpression(initializer.expression) ||
    !ts.isIdentifier(initializer.expression.expression)
  ) {
    throw new Error(`Renderer contract entry must use a typed builder: ${path}`)
  }
  const builder = initializer.expression.expression.text
  if (builder === 'value') continue
  if (builder !== 'callable') throw new Error(`Unknown renderer contract builder: ${builder}`)
  const metadata = initializer.arguments[1]
  if (!metadata || !ts.isArrayLiteralExpression(metadata)) {
    throw new Error(`Renderer contract metadata must be a tuple: ${path}`)
  }
  const projection = projectionFor(metadata.elements[1])
  if (projection === 'none') continue
  const channel = stringLiteral(metadata.elements[0], 'channel')
  const target = projection === 'invoke' ? invoke : events
  if (Object.hasOwn(target, path)) throw new Error(`Duplicate projected renderer path: ${path}`)
  target[path] = channel
}

const sorted = (value) =>
  Object.fromEntries(Object.entries(value).sort(([a], [b]) => a.localeCompare(b)))
const output = await format(
  `// Generated by scripts/generate-web-api-map.mjs. Do not edit by hand.
export const WEB_INVOKE_CHANNELS = ${JSON.stringify(sorted(invoke), null, 2)} as const

export const WEB_EVENT_CHANNELS = ${JSON.stringify(sorted(events), null, 2)} as const
`,
  {
    parser: 'typescript',
    singleQuote: true,
    semi: false,
    printWidth: 100,
    trailingComma: 'none'
  }
)

if (process.argv.includes('--check')) {
  const current = await readFile(outputPath, 'utf8').catch(() => '')
  if (current !== output) {
    console.error('Web API map is stale. Run npm run gen:web-api-map.')
    process.exitCode = 1
  }
} else {
  await writeFile(outputPath, output, 'utf8')
  console.log(`Generated ${outputPath}`)
}