var common = require('../common');
var assert = require('assert');
var fs = require('fs');
var path = require('path');
var exec = require('child_process').exec;
var async_completed = 0, async_expected = 0, unlink = [];

function tmp(p) {
  return path.join(common.tmpDir, p);
}

var fixturesAbsDir;
var tmpAbsDir;
function getAbsPaths(cb) {
  var failed = false;
  var did = 0;
  var expect = 2;
  bashRealpath(common.fixturesDir, function(er, path) {
    if (failed) return;
    if (er) return cb(failed = er);
    fixturesAbsDir = path;
    did++;
    if (did === expect) cb();
  });
  bashRealpath(common.tmpDir, function(er, path) {
    if (failed) return;
    if (er) return cb(failed = er);
    tmpAbsDir = path;
    did++;
    if (did === expect) cb();
  });
}

function asynctest(testBlock, args, callback, assertBlock) {
  async_expected++;
  testBlock.apply(testBlock, args.concat(function(err) {
    var ignoreError = false;
    if (assertBlock) {
      try {
        ignoreError = assertBlock.apply(assertBlock, arguments);
      }
      catch (e) {
        err = e;
      }
    }
    async_completed++;
    callback(ignoreError ? null : err);
  }));
}

function bashRealpath(path, callback) {
  exec("cd '" + path.replace("'", "\\'") + "' && pwd -P", function(err, o) {
    callback(err, o.trim());
  });
}

// sub-tests:

function test_simple_relative_symlink(callback) {
  console.log('test_simple_relative_symlink');
  var entry = common.tmpDir + '/symlink',
      expected = common.tmpDir + '/cycles/root.js';
  [
    [entry, '../tmp/cycles/root.js']
  ].forEach(function(t) {
    try {fs.unlinkSync(t[0]);}catch (e) {}
    fs.symlinkSync(t[1], t[0]);
    unlink.push(t[0]);
  });
  var result = fs.realpathSync(entry);
  assert.equal(result, expected,
      'got ' + common.inspect(result) + ' expected ' +
      common.inspect(expected));
  asynctest(fs.realpath, [entry], callback, function(err, result) {
    assert.equal(result, expected,
        'got ' +
        common.inspect(result) +
        ' expected ' +
        common.inspect(expected));
  });
}

function test_simple_absolute_symlink(callback) {
  console.log('test_simple_absolute_symlink');
  var entry = tmpAbsDir + '/symlink',
      expected = fixturesAbsDir + '/nested-index/one/index.js';
  [
    [entry, expected]
  ].forEach(function(t) {
    try {fs.unlinkSync(t[0]);} catch (e) {}
    fs.symlinkSync(t[1], t[0]);
    unlink.push(t[0]);
  });
  var result = fs.realpathSync(entry);
  assert.equal(result, expected,
      'got ' +
      common.inspect(result) +
      ' expected ' +
      common.inspect(expected));
  asynctest(fs.realpath, [entry], callback, function(err, result) {
    assert.equal(result, expected,
        'got ' +
        common.inspect(result) +
        ' expected ' +
        common.inspect(expected));
  });
}

function test_deep_relative_file_symlink(callback) {
  console.log('test_deep_relative_file_symlink');
  var expected = path.join(common.fixturesDir, 'cycles', 'root.js');
  var linkData1 = '../../cycles/root.js';
  var linkPath1 = path.join(common.fixturesDir,
                            'nested-index', 'one', 'symlink1.js');
  try {fs.unlinkSync(linkPath1);} catch (e) {}
  fs.symlinkSync(linkData1, linkPath1);

  var linkData2 = '../one/symlink1.js';
  var entry = path.join(common.fixturesDir,
                        'nested-index', 'two', 'symlink1-b.js');
  try {fs.unlinkSync(entry);} catch (e) {}
  fs.symlinkSync(linkData2, entry);
  unlink.push(linkPath1);
  unlink.push(entry);

  assert.equal(fs.realpathSync(entry), expected);
  asynctest(fs.realpath, [entry], callback, function(err, result) {
    assert.equal(result, expected,
        'got ' +
        common.inspect(result) +
        ' expected ' +
        common.inspect(expected));
  });
}

function test_deep_relative_dir_symlink(callback) {
  console.log('test_deep_relative_dir_symlink');
  var expected = path.join(common.fixturesDir, 'cycles', 'folder');
  var linkData1b = '../../cycles/folder';
  var linkPath1b = path.join(common.fixturesDir,
                             'nested-index', 'one', 'symlink1-dir');
  try {fs.unlinkSync(linkPath1b);} catch (e) {}
  fs.symlinkSync(linkData1b, linkPath1b);

  var linkData2b = '../one/symlink1-dir';
  var entry = path.join(common.fixturesDir,
                        'nested-index', 'two', 'symlink12-dir');
  try {fs.unlinkSync(entry);} catch (e) {}
  fs.symlinkSync(linkData2b, entry);
  unlink.push(linkPath1b);
  unlink.push(entry);

  assert.equal(fs.realpathSync(entry), expected);

  asynctest(fs.realpath, [entry], callback, function(err, result) {
    assert.equal(result, expected,
        'got ' +
        common.inspect(result) +
        ' expected ' +
        common.inspect(expected));
  });
}

function test_cyclic_link_protection(callback) {
  console.log('test_cyclic_link_protection');
  var entry = common.tmpDir + '/cycles/realpath-3a';
  [
    [entry, '../cycles/realpath-3b'],
    [common.tmpDir + '/cycles/realpath-3b', '../cycles/realpath-3c'],
    [common.tmpDir + '/cycles/realpath-3c', '../cycles/realpath-3a']
  ].forEach(function(t) {
    try {fs.unlinkSync(t[0]);} catch (e) {}
    fs.symlinkSync(t[1], t[0]);
    unlink.push(t[0]);
  });
  assert.throws(function() { fs.realpathSync(entry); });
  asynctest(fs.realpath, [entry], callback, function(err, result) {
    assert.ok(err && true);
    return true;
  });
}

function test_cyclic_link_overprotection(callback) {
  console.log('test_cyclic_link_overprotection');
  var cycles = common.tmpDir + '/cycles';
  var expected = fs.realpathSync(cycles);
  var folder = cycles + '/folder';
  var link = folder + '/cycles';
  var testPath = cycles;
  for (var i = 0; i < 10; i++) testPath += '/folder/cycles';
  try {fs.unlinkSync(link)} catch (ex) {}
  fs.symlinkSync(cycles, link);
  unlink.push(link);
  assert.equal(fs.realpathSync(testPath), expected);
  asynctest(fs.realpath, [testPath], callback, function(er, res) {
    assert.equal(res, expected);
  });
}

function test_relative_input_cwd(callback) {
  console.log('test_relative_input_cwd');
  var p = common.tmpDir.lastIndexOf('/');
  var entrydir = common.tmpDir.substr(0, p);
  var entry = common.tmpDir.substr(p + 1) + '/cycles/realpath-3a';
  var expected = common.tmpDir + '/cycles/root.js';
  [
    [entry, '../cycles/realpath-3b'],
    [common.tmpDir + '/cycles/realpath-3b', '../cycles/realpath-3c'],
    [common.tmpDir + '/cycles/realpath-3c', 'root.js']
  ].forEach(function(t) {
    var fn = t[0];
    if (fn.charAt(0) !== '/') fn = entrydir + '/' + fn;
    try {fs.unlinkSync(fn);} catch (e) {}
    fs.symlinkSync(t[1], fn);
    unlink.push(fn);
  });
  var origcwd = process.cwd();
  process.chdir(entrydir);
  assert.equal(fs.realpathSync(entry), expected);
  asynctest(fs.realpath, [entry], callback, function(err, result) {
    process.chdir(origcwd);
    assert.equal(result, expected,
        'got ' +
        common.inspect(result) +
        ' expected ' +
        common.inspect(expected));
    return true;
  });
}

function test_deep_symlink_mix(callback) {
  console.log('test_deep_symlink_mix');
  // todo: check to see that common.fixturesDir is not rooted in the
  //       same directory as our test symlink.
  // obtain our current realpath using bash (so we can test ourselves)
  /*
  /tmp/node-test-realpath-f1 -> ../tmp/node-test-realpath-d1/foo
  /tmp/node-test-realpath-d1 -> ../node-test-realpath-d2
  /tmp/node-test-realpath-d2/foo -> ../node-test-realpath-f2
  /tmp/node-test-realpath-f2
    -> /node/test/fixtures/nested-index/one/realpath-c
  /node/test/fixtures/nested-index/one/realpath-c
    -> /node/test/fixtures/nested-index/two/realpath-c
  /node/test/fixtures/nested-index/two/realpath-c -> ../../cycles/root.js
  /node/test/fixtures/cycles/root.js (hard)
  */
  var entry = tmp('node-test-realpath-f1');
  try { fs.unlinkSync(tmp('node-test-realpath-d2/foo')); } catch (e) {}
  try { fs.rmdirSync(tmp('node-test-realpath-d2')); } catch (e) {}
  fs.mkdirSync(tmp('node-test-realpath-d2'), 0700);
  try {
    [
      [entry, '../tmp/node-test-realpath-d1/foo'],
      [tmp('node-test-realpath-d1'), '../tmp/node-test-realpath-d2'],
      [tmp('node-test-realpath-d2/foo'), '../node-test-realpath-f2'],
      [tmp('node-test-realpath-f2'), fixturesAbsDir +
           '/nested-index/one/realpath-c'],
      [fixturesAbsDir + '/nested-index/one/realpath-c', fixturesAbsDir +
            '/nested-index/two/realpath-c'],
      [fixturesAbsDir + '/nested-index/two/realpath-c',
        '../../../tmp/cycles/root.js']
    ].forEach(function(t) {
      //common.debug('setting up '+t[0]+' -> '+t[1]);
      try { fs.unlinkSync(t[0]); } catch (e) {}
      fs.symlinkSync(t[1], t[0]);
      unlink.push(t[0]);
    });
  } finally {
    unlink.push(tmp('node-test-realpath-d2'));
  }
  var expected = tmpAbsDir + '/cycles/root.js';
  assert.equal(fs.realpathSync(entry), expected);
  asynctest(fs.realpath, [entry], callback, function(err, result) {
    assert.equal(result, expected,
        'got ' +
        common.inspect(result) +
        ' expected ' +
        common.inspect(expected));
    return true;
  });
}

function test_non_symlinks(callback) {
  console.log('test_non_symlinks');
  var p = tmpAbsDir.lastIndexOf('/');
  var entrydir = tmpAbsDir.substr(0, p);
  var entry = tmpAbsDir.substr(p + 1) + '/cycles/root.js';
  var expected = tmpAbsDir + '/cycles/root.js';
  var origcwd = process.cwd();
  process.chdir(entrydir);
  assert.equal(fs.realpathSync(entry), expected);
  asynctest(fs.realpath, [entry], callback, function(err, result) {
    process.chdir(origcwd);
    assert.equal(result, expected,
        'got ' +
        common.inspect(result) +
        ' expected ' +
        common.inspect(expected));
    return true;
  });
}

var upone = path.join(process.cwd(), '..');
function test_escape_cwd(cb) {
  console.log('test_escape_cwd');
  asynctest(fs.realpath, ['..'], cb, function(er, uponeActual) {
    assert.equal(upone, uponeActual,
        'realpath("..") expected: ' + upone + ' actual:' + uponeActual);
  });
}
var uponeActual = fs.realpathSync('..');
assert.equal(upone, uponeActual,
    'realpathSync("..") expected: ' + upone + ' actual:' + uponeActual);

// absolute symlinks with children.
// .
// `-- a/
//     |-- b/
//     |   `-- c/
//     |       `-- x.txt
//     `-- link -> /tmp/node-test-realpath-abs-kids/a/b/
// realpath(root+'/a/link/c/x.txt') ==> root+'/a/b/c/x.txt'
function test_abs_with_kids(cb) {
  console.log('test_abs_with_kids');
  var root = tmpAbsDir + '/node-test-realpath-abs-kids';
  function cleanup() {
    ['/a/b/c/x.txt',
      '/a/link'
    ].forEach(function(file) {
      try {fs.unlinkSync(root + file)} catch (ex) {}
    });
    ['/a/b/c',
      '/a/b',
      '/a',
      ''
    ].forEach(function(folder) {
      try {fs.rmdirSync(root + folder)} catch (ex) {}
    });
  }
  function setup() {
    cleanup();
    ['',
      '/a',
      '/a/b',
      '/a/b/c'
    ].forEach(function(folder) {
      console.log('mkdir ' + root + folder);
      fs.mkdirSync(root + folder, 0700);
    });
    fs.writeFileSync(root + '/a/b/c/x.txt', 'foo');
    fs.symlinkSync(root + '/a/b', root + '/a/link');
  }
  setup();
  var linkPath = root + '/a/link/c/x.txt';
  var expectPath = root + '/a/b/c/x.txt';
  var actual = fs.realpathSync(linkPath);
  // console.log({link:linkPath,expect:expectPath,actual:actual},'sync');
  assert.equal(actual, expectPath);
  asynctest(fs.realpath, [linkPath], cb, function(er, actual) {
    // console.log({link:linkPath,expect:expectPath,actual:actual},'async');
    assert.equal(actual, expectPath);
    cleanup();
  });
}

function test_lying_cache_liar(cb) {
  // this should not require *any* stat calls, since everything
  // checked by realpath will be found in the cache.
  console.log('test_lying_cache_liar');
  var cache = { '/foo/bar/baz/bluff' : '/foo/bar/bluff',
                '/1/2/3/4/5/6/7' : '/1',
                '/a' : '/a',
                '/a/b' : '/a/b',
                '/a/b/c' : '/a/b',
                '/a/b/d' : '/a/b/d' };
  var rps = fs.realpathSync('/foo/bar/baz/bluff', cache);
  assert.equal(cache['/foo/bar/baz/bluff'], rps);
  fs.realpath('/1/2/3/4/5/6/7', cache, function(er, rp) {
    assert.equal(cache['/1/2/3/4/5/6/7'], rp);
  });

  var test = '/a/b/c/d',
      expect = '/a/b/d';
  var actual = fs.realpathSync(test, cache);
  assert.equal(expect, actual);
  fs.realpath(test, cache, function(er, actual) {
    assert.equal(expect, actual);
  });
}

// ----------------------------------------------------------------------------

var tests = [
  test_simple_relative_symlink,
  test_simple_absolute_symlink,
  test_deep_relative_file_symlink,
  test_deep_relative_dir_symlink,
  test_cyclic_link_protection,
  test_cyclic_link_overprotection,
  test_relative_input_cwd,
  test_deep_symlink_mix,
  test_non_symlinks,
  test_escape_cwd,
  test_abs_with_kids,
  test_lying_cache_liar
];
var numtests = tests.length;
function runNextTest(err) {
  if (err) throw err;
  var test = tests.shift();
  if (!test) console.log(numtests +
                         ' subtests completed OK for fs.realpath');
  else test(runNextTest);
}
getAbsPaths(function(er) {
  if (er) throw er;
  var tmpDirs = ['cycles', 'cycles/folder'];
  tmpDirs.forEach(function(t) {
    t = tmp(t);
    var s;
    try { s = fs.statSync(t); } catch (ex) {}
    if (s) return;
    fs.mkdirSync(t, 0700);
  });
  fs.writeFileSync(tmp('cycles/root.js'), "console.error('roooot!');");
  runNextTest();
});


assert.equal('/', fs.realpathSync('/'));
fs.realpath('/', function(err, result) {
  assert.equal(null, err);
  assert.equal('/', result);
});



process.addListener('exit', function() {
  unlink.forEach(function(path) { try {fs.unlinkSync(path);} catch (e) {} });
  assert.equal(async_completed, async_expected);
});