#!/usr/bin/env node
'use strict';

var fs = require('fs');
var path = require('path');
var webppl = require('./src/main');
var pkg = require('./src/pkg');
var util = require('./src/util');
var parseArgs = require('minimist');
var git = require('git-rev-2');
var _ = require('underscore');

function printWebPPLValue(x) {
  if (isErp(x)) {
    x.print();
  } else {
    console.log(x);
  }
}

function run(code, packages, verbose) {
  packages.forEach(function(pkg) {
    if (pkg.js) { global[pkg.js.identifier] = require(pkg.js.path); }
    pkg.headers.forEach(webppl.requireHeader);
  });

  webppl.run(
      code,
      function(s, x) {
        console.log('\n* Program return value:\n');
        printWebPPLValue(x);
      },
      {
        extra: webppl.parsePackageCode(packages, verbose),
        verbose: verbose
      });
}

function compile(code, packages, verbose, outputFile) {
  var compiledCode = 'var webppl = require("' + require.resolve('./src/main') + '");\n';
  packages.forEach(function(pkg) {
    if (pkg.js) { compiledCode += 'var ' + pkg.js.identifier + ' = require("' + pkg.js.path + '");\n'; }
    pkg.headers.forEach(function(header) {
      compiledCode += 'webppl.requireHeader("' + header + '");\n';
    });
  });

  var compileOptions = { extra: webppl.parsePackageCode(packages, verbose), verbose: verbose };

  compiledCode += (
      printWebPPLValue.toString() + '\n' +
      'var topK = function(s, x){ \n' +
      " console.log('\\n* Program return value:\\n'); \n" +
      ' printWebPPLValue(x); \n};\n\n');
  compiledCode += 'var main = ' + webppl.compile(code, compileOptions) + '\n\n';
  compiledCode += "main({}, topK, '');";
  // Write Javascript code to file
  fs.writeFile(
      outputFile,
      compiledCode,
      function(err) {
        if (err) {
          console.log(err);
        } else {
          console.log('Wrote webppl code to', outputFile);
        }
      });
}

function main() {

  var argv = parseArgs(process.argv.slice(2));

  // Print version if requested
  if (argv.version) {
    git.branch(
        __dirname,
        function(err, branch) {
          __dirname,
          git.short(
              function(err, shortName) {
                console.log(branch, shortName, __dirname);
              });
        }
    );
    return;
  }

  // Return if no file argument given
  if (argv._[0] === undefined) {
    console.log('No program argument given! Run webppl as follows:');
    console.log('webppl program.wppl [--compile] [--out compiled.js] ' +
                '[--require path] [--random-seed int]');
    return;
  }

  // Load webppl code
  var programFile = argv._[0];
  console.log('Processing', programFile);

  var code = fs.readFileSync(programFile, 'utf8');
  var processCode = argv.compile ? compile : run;
  var outputFile = argv.out ? argv.out : 'tmp.js';

  var packagePaths = [
    path.join(path.dirname(programFile), 'node_modules'),
    pkg.globalPkgDir()
  ];

  var packages = util.asArray(argv.require).map(function(name_or_path) {
    return pkg.load(pkg.read(name_or_path, packagePaths, argv.verbose));
  });

  var seed = argv['random-seed'];
  if (seed !== undefined) {
    util.assertValidRandomSeed(seed);
    util.seedRNG(seed);
  }

  processCode(code, packages, argv.verbose, outputFile);
}

main();