/* eslint suggest-no-throw/suggest-no-throw: 0 */
import * as vscode from 'vscode'
import { strict as nativeAssert } from 'assert'
import { exec, type ExecOptions, spawnSync } from 'child_process'
import { inspect } from 'util'

export interface Env {
  [name: string]: string
}

export function assert(
  condition: boolean,
  explanation: string
): asserts condition {
  try {
    nativeAssert(condition, explanation)
  } catch (err) {
    log.error(`Assertion failed:`, explanation)
    throw err
  }
}

class Logger {
  private enabled = true
  private readonly output = vscode.window.createOutputChannel(
    'KittyCAD Language Client'
  )

  setEnabled(yes: boolean): void {
    log.enabled = yes
  }

  // Hint: the type [T, ...T[]] means a non-empty array
  debug(...msg: [unknown, ...unknown[]]): void {
    if (!log.enabled) return
    log.write('DEBUG', ...msg)
  }

  info(...msg: [unknown, ...unknown[]]): void {
    log.write('INFO', ...msg)
  }

  warn(...msg: [unknown, ...unknown[]]): void {
    debugger
    log.write('WARN', ...msg)
  }

  error(...msg: [unknown, ...unknown[]]): void {
    debugger
    log.write('ERROR', ...msg)
    log.output.show(true)
  }

  private write(label: string, ...messageParts: unknown[]): void {
    const message = messageParts.map(log.stringify).join(' ')
    const dateTime = new Date().toLocaleString()
    log.output.appendLine(`${label} [${dateTime}]: ${message}`)
  }

  private stringify(val: unknown): string {
    if (typeof val === 'string') return val
    return inspect(val, {
      colors: false,
      depth: 6, // heuristic
    })
  }
}

export const log = new Logger()

export function sleep(ms: number) {
  return new Promise((resolve) => setTimeout(resolve, ms))
}

export type KclDocument = vscode.TextDocument & { languageId: 'kcl' }
export type KclEditor = vscode.TextEditor & { document: KclDocument }

export function isKclDocument(
  document: vscode.TextDocument
): document is KclDocument {
  // Prevent corrupted text (particularly via inlay hints) in diff views
  // by allowing only `file` schemes
  // unfortunately extensions that use diff views not always set this
  // to something different than 'file' (see ongoing bug: #4608)
  return document.languageId === 'kcl' && document.uri.scheme === 'file'
}

export function isCargoTomlDocument(
  document: vscode.TextDocument
): document is KclDocument {
  // ideally `document.languageId` should be 'toml' but user maybe not have toml extension installed
  return (
    document.uri.scheme === 'file' && document.fileName.endsWith('Cargo.toml')
  )
}

export function isKclEditor(editor: vscode.TextEditor): editor is KclEditor {
  return isKclDocument(editor.document)
}

export function isDocumentInWorkspace(document: KclDocument): boolean {
  const workspaceFolders = vscode.workspace.workspaceFolders
  if (!workspaceFolders) {
    return false
  }
  for (const folder of workspaceFolders) {
    if (document.uri.fsPath.startsWith(folder.uri.fsPath)) {
      return true
    }
  }
  return false
}

export function isValidExecutable(path: string): boolean {
  log.debug('Checking availability of a binary at', path)

  const res = spawnSync(path, ['--version'], {
    encoding: 'utf8',
    env: { ...process.env },
  })

  const printOutput = res.error ? log.warn : log.info
  printOutput(path, '--version:', res)

  return res.status === 0
}

/** Sets ['when'](https://code.visualstudio.com/docs/getstarted/keybindings#_when-clause-contexts) clause contexts */
export function setContextValue(key: string, value: any): Thenable<void> {
  return vscode.commands.executeCommand('setContext', key, value)
}

/**
 * Returns a higher-order function that caches the results of invoking the
 * underlying async function.
 */
export function memoizeAsync<Ret, TThis, Param extends string>(
  func: (this: TThis, arg: Param) => Promise<Ret>
) {
  const cache = new Map<string, Ret>()

  return async function (this: TThis, arg: Param) {
    const cached = cache.get(arg)
    if (cached) return cached

    const result = await func.call(this, arg)
    cache.set(arg, result)

    return result
  }
}

/** Awaitable wrapper around `child_process.exec` */
export function execute(
  command: string,
  options: ExecOptions
): Promise<string> {
  log.info(`running command: ${command}`)
  return new Promise((resolve, reject) => {
    exec(command, options, (err, stdout, stderr) => {
      if (err) {
        log.error(err)
        reject(err)
        return
      }

      if (stderr) {
        reject(new Error(stderr))
        return
      }

      resolve(stdout.trimEnd())
    })
  })
}

export function executeDiscoverProject(
  command: string,
  options: ExecOptions
): Promise<string> {
  options = Object.assign({ maxBuffer: 10 * 1024 * 1024 }, options)
  log.info(`running command: ${command}`)
  return new Promise((resolve, reject) => {
    exec(command, options, (err, stdout, _) => {
      if (err) {
        log.error(err)
        reject(err)
        return
      }

      resolve(stdout.trimEnd())
    })
  })
}

export class LazyOutputChannel implements vscode.OutputChannel {
  constructor(name: string) {
    this.name = name
  }

  name: string
  _channel: vscode.OutputChannel | undefined

  get channel(): vscode.OutputChannel {
    if (!this._channel) {
      this._channel = vscode.window.createOutputChannel(this.name)
    }
    return this._channel
  }

  append(value: string): void {
    this.channel.append(value)
  }
  appendLine(value: string): void {
    this.channel.appendLine(value)
  }
  replace(value: string): void {
    this.channel.replace(value)
  }
  clear(): void {
    if (this._channel) {
      this._channel.clear()
    }
  }
  show(preserveFocus?: boolean): void
  show(column?: vscode.ViewColumn, preserveFocus?: boolean): void
  show(column?: any, preserveFocus?: any): void {
    this.channel.show(column, preserveFocus)
  }
  hide(): void {
    if (this._channel) {
      this._channel.hide()
    }
  }
  dispose(): void {
    if (this._channel) {
      this._channel.dispose()
    }
  }
}