// Copyright 2013 Traceur Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

'use strict';

var path = require('path');
var glob = require('glob');
var commandLine;
var cmdName = path.basename(process.argv[1]);
try {
  commandLine = new (require('commander').Command)(cmdName);
} catch (ex) {
  console.error('Commander.js is required for this to work. To install it ' +
                'run:\n\n  npm install commander\n');
  process.exit(1);
}
commandLine.setMaxListeners(100);

var traceurAPI = require('./api.js');
var interpret = require('./interpreter.js');

// The System object requires traceur, but we want it set for everything that
// follows. The module sets global.System as a side-effect.
require('./System.js');

var rootSources = [];
commandLine.option('--script <fileName>', 'Parse as Script', function(fileName) {
  rootSources.push({name: fileName, type: 'script'});
});

commandLine.option('--module <fileName>', 'Parse as Module', function(fileName) {
   rootSources.push({name: fileName, type: 'module'});
});

commandLine.option('--inline <fileName>', 'Parse as Module, format \'inline\'',
  function(fileName) {
   rootSources.push({name: fileName, type: 'module', format: 'inline'});
  }
);

commandLine.option('--out <FILE>', 'Compile all input files into a single file');
commandLine.option('--dir <INDIR> <OUTDIR>', 'Compile an input directory of modules into an output directory');

commandLine.option('--longhelp', 'Show all known options');
commandLine.on('longhelp', function() {
  commandLine.help();
  process.exit();
});

// Caling process.exit when there is still characters to be flushed to stdout
// makes Windows drop those characters. We therefor wait until the buffer is
// empty before really exiting.
// Since this makes exiting async we need to manually keep track
var shouldExit = false;

function processExit() {
  shouldExit = true;
  var draining = 0;
  function exit() {
    if (!draining--)
      process.exit();
  }
  if (process.stdout.bufferSize) {
    draining += 1;
    process.stdout.once('drain', exit);
  }
  if (process.stderr.bufferSize) {
    draining += 1;
    process.stderr.once('drain', exit);
  }
  exit();
}

commandLine.option('-v, --version', 'Show version and exit');
commandLine.on('version', function() {
  process.stdout.write(System.version.split('@')[1]);
  processExit();
});

commandLine.on('--help', function() {
  console.log('  Examples:');
  console.log('');
  console.log('    $ %s a.js [args]', cmdName);
  console.log('    $ %s --out compiled.js b.js c.js', cmdName);
  console.log('    $ %s --dir indir outdir', cmdName);
  console.log('');
});

var commandOptions = new traceurAPI.util.CommandOptions();
traceurAPI.util.addOptions(commandLine, commandOptions);

commandLine.usage('[options] [files]');

commandLine.command('*').action(function() {
    // The callback seems to receive a "command" at the end of arguments
    for (var i = 0; i < arguments.length - 1; i++) {
      rootSources.push({name: arguments[i], type: 'module'});
    }
  });

commandLine.sourceMaps = false;
commandLine.parse(process.argv);

// commanderjs sets self[name]=defaultValue if the argument is null.
// To support --source-maps a legacy boolean we need to transfer the
// the self value here.
commandOptions.sourceMaps = commandLine.sourceMaps;

// Set the global options for back compat, but try to use options by argument.
traceurAPI.options.setFromObject(commandOptions);

if (!shouldExit && !rootSources.length) {
  // TODO: Start trepl
  console.error('\n  Error: At least one input file is needed');
  commandLine.help();
  process.exit(1);
}

var out = commandLine.out;
var dir = commandLine.dir;

function compileAll(out, sources, options) {
  var isSingleFileCompile = /\.js$/.test(out);
  if (!isSingleFileCompile) {
    traceurAPI.forEachRecursiveModuleCompile(out, sources, options);
  } else {
    traceurAPI.recursiveModuleCompileToSingleFile(out, sources, options).then(function() {
      process.exit(0);
    }).catch(function(err) {
      var errors = err.errors || [err];
      errors.forEach(function(err) {
        console.error(err.stack || err);
      });
      process.exit(1);
    });
  }
}

function globSources(sourcesToGlob, cb) {
  var processedCount = 0;
  var globbedSources = [];
  sourcesToGlob.forEach(function(item) {
    glob(item.name, {}, function(err, matches) {
      if (err)
        throw new Error('While scanning ' + item.name + ': ' + err);
      for (var i = matches.length - 1; i >= 0; i--) {
        var globbedSource = {
          name: matches[i],
          type: item.type,
          format: item.format
        };
        globbedSources.push(globbedSource);
      }
      processedCount++;
      if (processedCount === sourcesToGlob.length) {
        cb(null, globbedSources);
      }
    });
  });
}

if (!shouldExit) {
  if (out) {
    var sourcesToGlob = [];
    var processedSources = [];

    for (var i = 0; i < rootSources.length; i++) {
      if (glob.hasMagic(rootSources[i].name)) {
        sourcesToGlob.push(rootSources[i]);
      } else {
        processedSources.push(rootSources[i]);
      }
    }
    if (!sourcesToGlob.length) {
      compileAll(out, processedSources, commandOptions);
    } else {
      globSources(sourcesToGlob, function(err, globbedSources) {
        processedSources.push.apply(processedSources, globbedSources);
        if (processedSources.length) {
          compileAll(out, processedSources, commandOptions);
        } else {
          process.exit(0);
        }
      });
    }
  } else if (dir) {
    if (rootSources.length !== 1)
      throw new Error('Compile all in directory requires exactly one input filename');
    traceurAPI.compileAllJsFilesInDir(dir, rootSources[0].name, commandOptions);
  } else {
    rootSources.forEach(function(obj) {
      interpret(path.resolve(obj.name), commandOptions);
    });
  }
}
