/**
MIT License

Copyright (c) 2013-present, Facebook, Inc.

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/
// This file is based on https://github.com/facebook/create-react-app/blob/v1.1.4/packages/react-dev-utils/formatWebpackMessages.js
// It's been edited to remove chalk

'use strict'

// Some custom utilities to prettify Webpack output.
// This is quite hacky and hopefully won't be needed when Webpack fixes this.
// https://github.com/webpack/webpack/issues/2878

var friendlySyntaxErrorLabel = 'Syntax error:'

function isLikelyASyntaxError (message) {
  return message.indexOf(friendlySyntaxErrorLabel) !== -1
}

// Cleans up webpack error messages.
// eslint-disable-next-line no-unused-vars
function formatMessage (message, isError) {
  var lines = message.split('\n')

  if (lines.length > 2 && lines[1] === '') {
    // Remove extra newline.
    lines.splice(1, 1)
  }

  // Remove webpack-specific loader notation from filename.
  // Before:
  // ./~/css-loader!./~/postcss-loader!./src/App.css
  // After:
  // ./src/App.css
  if (lines[0].lastIndexOf('!') !== -1) {
    lines[0] = lines[0].substr(lines[0].lastIndexOf('!') + 1)
  }

  // Remove unnecessary stack added by `thread-loader`
  var threadLoaderIndex = -1
  lines.forEach(function (line, index) {
    if (threadLoaderIndex !== -1) {
      return
    }
    if (/thread.loader/i.test(line)) {
      threadLoaderIndex = index
    }
  })

  if (threadLoaderIndex !== -1) {
    lines = lines.slice(0, threadLoaderIndex)
  }

  lines = lines.filter(function (line) {
    // Webpack adds a list of entry points to warning messages:
    //  @ ./src/index.js
    //  @ multi react-scripts/~/react-dev-utils/webpackHotDevClient.js ...
    // It is misleading (and unrelated to the warnings) so we clean it up.
    // It is only useful for syntax errors but we have beautiful frames for them.
    return line.indexOf(' @ ') !== 0
  })

  // line #0 is filename
  // line #1 is the main error message
  if (!lines[0] || !lines[1]) {
    return lines.join('\n')
  }

  // Cleans up verbose "module not found" messages for files and packages.
  if (lines[1].indexOf('Module not found: ') === 0) {
    lines = [
      lines[0],
      // Clean up message because "Module not found: " is descriptive enough.
      lines[1]
        .replace("Cannot resolve 'file' or 'directory' ", '')
        .replace('Cannot resolve module ', '')
        .replace('Error: ', '')
        .replace('[CaseSensitivePathsPlugin] ', '')
    ]
  }

  // Cleans up syntax error messages.
  if (lines[1].indexOf('Module build failed: ') === 0) {
    lines[1] = lines[1].replace(
      'Module build failed: SyntaxError:',
      friendlySyntaxErrorLabel
    )
  }

  // Clean up export errors.
  // TODO: we should really send a PR to Webpack for this.
  var exportError = /\s*(.+?)\s*(")?export '(.+?)' was not found in '(.+?)'/
  if (lines[1].match(exportError)) {
    lines[1] = lines[1].replace(
      exportError,
      "$1 '$4' does not contain an export named '$3'."
    )
  }

  // Reassemble the message.
  message = lines.join('\n')
  // Internal stacks are generally useless so we strip them... with the
  // exception of stacks containing `webpack:` because they're normally
  // from user code generated by WebPack. For more information see
  // https://github.com/facebook/create-react-app/pull/1050
  message = message.replace(
    /^\s*at\s((?!webpack:).)*:\d+:\d+[\s)]*(\n|$)/gm,
    ''
  ) // at ... ...:x:y

  return message.trim()
}

function formatWebpackMessages (json) {
  var formattedErrors = json.errors.map(function (message) {
    return formatMessage(message, true)
  })
  var formattedWarnings = json.warnings.map(function (message) {
    return formatMessage(message, false)
  })
  var result = {
    errors: formattedErrors,
    warnings: formattedWarnings
  }
  if (result.errors.some(isLikelyASyntaxError)) {
    // If there are any syntax errors, show just them.
    // This prevents a confusing ESLint parsing error
    // preceding a much more useful Babel syntax error.
    result.errors = result.errors.filter(isLikelyASyntaxError)
  }
  return result
}

module.exports = formatWebpackMessages