#!/usr/bin/env node

'use strict';

require = require('esm')(module);

const fs = require('fs');
const path = require('path');
const request = require('request');

const MBTiles = require('@mapbox/mbtiles');

const packageJson = require('../package');

const args = process.argv;
if (args.length >= 3 && args[2][0] !== '-') {
  args.splice(2, 0, '--mbtiles');
}

const opts = require('commander')
  .description('tileserver-gl startup options')
  .usage('tileserver-gl [mbtiles] [options]')
  .option(
    '--mbtiles <file>',
    'MBTiles file (uses demo configuration);\n' +
    '\t                  ignored if the configuration file is also specified'
  )
  .option(
    '-c, --config <file>',
    'Configuration file [config.json]',
    'config.json'
  )
  .option(
    '-b, --bind <address>',
    'Bind address'
  )
  .option(
    '-p, --port <port>',
    'Port [8080]',
    8080,
    parseInt
  )
  .option(
    '-C|--no-cors',
    'Disable Cross-origin resource sharing headers'
  )
  .option(
    '-u|--public_url <url>',
    'Enable exposing the server on subpaths, not necessarily the root of the domain'
  )
  .option(
    '-V, --verbose',
    'More verbose output'
  )
  .option(
    '-s, --silent',
    'Less verbose output'
  )
  .option(
    '-l|--log_file <file>',
    'output log file (defaults to standard out)'
  )
  .option(
    '-f|--log_format <format>',
    'define the log format:  https://github.com/expressjs/morgan#morganformat-options'
  )
  .version(
    packageJson.version,
    '-v, --version'
  )
  .parse(args);

console.log(`Starting ${packageJson.name} v${packageJson.version}`);

const startServer = (configPath, config) => {
  let publicUrl = opts.public_url;
  if (publicUrl && publicUrl.lastIndexOf('/') !== publicUrl.length - 1) {
    publicUrl += '/';
  }
  return require('./server')({
    configPath: configPath,
    config: config,
    bind: opts.bind,
    port: opts.port,
    cors: opts.cors,
    verbose: opts.verbose,
    silent: opts.silent,
    logFile: opts.log_file,
    logFormat: opts.log_format,
    publicUrl: publicUrl
  });
};

const startWithMBTiles = (mbtilesFile) => {
  console.log(`[INFO] Automatically creating config file for ${mbtilesFile}`);
  console.log(`[INFO] Only a basic preview style will be used.`);
  console.log(`[INFO] See documentation to learn how to create config.json file.`);

  mbtilesFile = path.resolve(process.cwd(), mbtilesFile);

  const mbtilesStats = fs.statSync(mbtilesFile);
  if (!mbtilesStats.isFile() || mbtilesStats.size === 0) {
    console.log(`ERROR: Not valid MBTiles file: ${mbtilesFile}`);
    process.exit(1);
  }
  const instance = new MBTiles(mbtilesFile, (err) => {
    if (err) {
      console.log('ERROR: Unable to open MBTiles.');
      console.log(`       Make sure ${path.basename(mbtilesFile)} is valid MBTiles.`);
      process.exit(1);
    }

    instance.getInfo((err, info) => {
      if (err || !info) {
        console.log('ERROR: Metadata missing in the MBTiles.');
        console.log(`       Make sure ${path.basename(mbtilesFile)} is valid MBTiles.`);
        process.exit(1);
      }
      const bounds = info.bounds;

      const styleDir = path.resolve(__dirname, "../node_modules/tileserver-gl-styles/");

      const config = {
        "options": {
          "paths": {
            "root": styleDir,
            "fonts": "fonts",
            "styles": "styles",
            "mbtiles": path.dirname(mbtilesFile)
          }
        },
        "styles": {},
        "data": {}
      };

      if (info.format === 'pbf' &&
        info.name.toLowerCase().indexOf('openmaptiles') > -1) {

        config['data'][`v3`] = {
          "mbtiles": path.basename(mbtilesFile)
        };


        const styles = fs.readdirSync(path.resolve(styleDir, 'styles'));
        for (let styleName of styles) {
          const styleFileRel = styleName + '/style.json';
          const styleFile = path.resolve(styleDir, 'styles', styleFileRel);
          if (fs.existsSync(styleFile)) {
            config['styles'][styleName] = {
              "style": styleFileRel,
              "tilejson": {
                "bounds": bounds
              }
            };
          }
        }
      } else {
        console.log(`WARN: MBTiles not in "openmaptiles" format. Serving raw data only...`);
        config['data'][(info.id || 'mbtiles')
                           .replace(/\//g, '_')
                           .replace(/:/g, '_')
                           .replace(/\?/g, '_')] = {
          "mbtiles": path.basename(mbtilesFile)
        };
      }

      if (opts.verbose) {
        console.log(JSON.stringify(config, undefined, 2));
      } else {
        console.log('Run with --verbose to see the config file here.');
      }

      return startServer(null, config);
    });
  });
};

fs.stat(path.resolve(opts.config), (err, stats) => {
  if (err || !stats.isFile() || stats.size === 0) {
    let mbtiles = opts.mbtiles;
    if (!mbtiles) {
      // try to find in the cwd
      const files = fs.readdirSync(process.cwd());
      for (let filename of files) {
        if (filename.endsWith('.mbtiles')) {
          const mbTilesStats = fs.statSync(filename);
          if (mbTilesStats.isFile() && mbTilesStats.size > 0) {
            mbtiles = filename;
            break;
          }
        }
      }
      if (mbtiles) {
        console.log(`No MBTiles specified, using ${mbtiles}`);
        return startWithMBTiles(mbtiles);
      } else {
        const url = 'https://github.com/maptiler/tileserver-gl/releases/download/v1.3.0/zurich_switzerland.mbtiles';
        const filename = 'zurich_switzerland.mbtiles';
        const stream = fs.createWriteStream(filename);
        console.log(`No MBTiles found`);
        console.log(`[DEMO] Downloading sample data (${filename}) from ${url}`);
        stream.on('finish', () => startWithMBTiles(filename));
        return request.get(url).pipe(stream);
      }
    }
    if (mbtiles) {
      return startWithMBTiles(mbtiles);
    }
  } else {
    console.log(`Using specified config file from ${opts.config}`);
    return startServer(opts.config, null);
  }
});