// Copyright 2012 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
//       copyright notice, this list of conditions and the following
//       disclaimer in the documentation and/or other materials provided
//       with the distribution.
//     * Neither the name of Google Inc. nor the names of its
//       contributors may be used to endorse or promote products derived
//       from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

module.exports = { versionCheck };

// Don't execute when required directly instead of being eval'd from
// lib/internal/v8_prof_processor.js.  This way we can test functions
// from this file in isolation.
if (module.id === 'internal/v8_prof_polyfill') return;

// Node polyfill
const fs = require('fs');
const cp = require('child_process');
const os = {
  system: function(name, args) {
    if (process.platform === 'linux' && name === 'nm') {
      // Filter out vdso and vsyscall entries.
      const arg = args[args.length - 1];
      if (arg === '[vdso]' ||
          arg == '[vsyscall]' ||
          /^[0-9a-f]+-[0-9a-f]+$/.test(arg)) {
        return '';
      }
    }
    let out = cp.spawnSync(name, args).stdout.toString();
    // Auto c++filt names, but not [iItT]
    if (process.platform === 'darwin' && name === 'nm')
      out = macCppfiltNm(out);
    return out;
  }
};
const print = console.log;
function read(fileName) {
  return fs.readFileSync(fileName, 'utf8');
}
const quit = process.exit;

// Polyfill "readline()".
const logFile = arguments[arguments.length - 1];
try {
  fs.accessSync(logFile);
} catch(e) {
  console.error('Please provide a valid isolate file as the final argument.');
  process.exit(1);
}
const fd = fs.openSync(logFile, 'r');
const buf = Buffer.allocUnsafe(4096);
const dec = new (require('string_decoder').StringDecoder)('utf-8');
var line = '';

{
  const message = versionCheck(peekline(), process.versions.v8);
  if (message) console.log(message);
}

function peekline() {
  const s = readline();
  line = `${s}\n${line}`;
  return s;
}

function readline() {
  while (true) {
    const lineBreak = line.indexOf('\n');
    if (lineBreak !== -1) {
      const res = line.slice(0, lineBreak);
      line = line.slice(lineBreak + 1);
      return res;
    }
    const bytes = fs.readSync(fd, buf, 0, buf.length);
    line += dec.write(buf.slice(0, bytes));
    if (line.length === 0) {
      return '';
    }
    if (bytes === 0) {
      process.emitWarning(`Profile file ${logFile} is broken`, {
        code: 'BROKEN_PROFILE_FILE',
        detail: `${JSON.stringify(line)} at the file end is broken`
      });
      return '';
    }
  }
}

function versionCheck(firstLine, expected) {
  // v8-version looks like
  // "v8-version,$major,$minor,$build,$patch[,$embedder],$candidate"
  // whereas process.versions.v8 is either "$major.$minor.$build-$embedder" or
  // "$major.$minor.$build.$patch-$embedder".
  firstLine = firstLine.split(',');
  const curVer = expected.split(/[.\-]/);
  if (firstLine.length !== 6 && firstLine.length !== 7 ||
      firstLine[0] !== 'v8-version') {
    return 'Unable to read v8-version from log file.';
  }
  // Compare major, minor and build; ignore the patch and candidate fields.
  for (var i = 0; i < 3; i++)
    if (curVer[i] !== firstLine[i + 1])
      return 'Testing v8 version different from logging version';
}

function macCppfiltNm(out) {
  // Re-grouped copy-paste from `tickprocessor.js`
  const FUNC_RE = /^([0-9a-fA-F]{8,16} [iItT] )(.*)$/gm;
  const CLEAN_RE = /^[0-9a-fA-F]{8,16} [iItT] /;
  let entries = out.match(FUNC_RE);
  if (entries === null)
    return out;

  entries = entries.map((entry) => {
    return entry.replace(CLEAN_RE, '')
  });

  let filtered;
  try {
    filtered = cp.spawnSync('c++filt', [ '-p' , '-i' ], {
      input: entries.join('\n')
    }).stdout.toString();
  } catch {
    return out;
  }

  let i = 0;
  filtered = filtered.split('\n');
  return out.replace(FUNC_RE, (all, prefix, postfix) => {
    return prefix + (filtered[i++] || postfix);
  });
}