/* global PouchDB */
/* jshint -W079 */
'use strict';

var testUtils = {};

function uniq(list) {
  var map = {};
  list.forEach(function (item) {
    map[item] = true;
  });
  return Object.keys(map);
}

testUtils.params = function () {
  if (typeof module !== 'undefined' && module.exports) {
    return process.env;
  }
  var paramStr = document.location.search.slice(1);
  return paramStr.split('&').reduce(function (acc, val) {
    if (!val) {
      return acc;
    }
    var tmp = val.split('=');
    acc[tmp[0]] = tmp[1] || true;
    return acc;
  }, {});
};

testUtils.couchHost = function () {
  if (typeof module !== 'undefined' && module.exports) {
    return process.env.COUCH_HOST || 'http://localhost:5984';
  } else if (window && window.COUCH_HOST) {
    return window.COUCH_HOST;
  } else if (window && window.cordova) {
    // magic route to localhost on android emulator
    return 'http://10.0.2.2:2020';
  }
  // In the browser we default to the CORS server, in future will change
  return 'http://localhost:2020';
};

testUtils.makeBlob = function (data, type) {
  if (typeof module !== 'undefined' && module.exports) {
    return new Buffer(data);
  } else {
    return PouchDB.utils.createBlob([data], { type: type });
  }
};

testUtils.readBlob = function (blob, callback) {
  if (typeof module !== 'undefined' && module.exports) {
    callback(blob.toString());
  } else {
    var reader = new FileReader();
    reader.onloadend = function (e) {
      
      var binary = "";
      var bytes = new Uint8Array(this.result);
      var length = bytes.byteLength;
      
      for (var i = 0; i < length; i++) {
        binary += String.fromCharCode(bytes[i]);
      }
      
      callback(binary);
    };
    reader.readAsArrayBuffer(blob);
  }
};

testUtils.base64Blob = function (blob, callback) {
  if (typeof module !== 'undefined' && module.exports) {
    callback(blob.toString('base64'));
  } else {
    var reader = new FileReader();
    reader.onloadend = function (e) {
      var base64 = this.result.replace(/data:.*;base64,/, '');
      callback(base64);
    };
    reader.readAsDataURL(blob);
  }
};

// Prefix http adapter database names with their host and
// node adapter ones with a db location
testUtils.adapterUrl = function (adapter, name) {
  if (adapter === 'http') {
    return testUtils.couchHost() + '/' + name;
  }
  return name;
};

// Delete specified databases
testUtils.cleanup = function (dbs, done) {

  dbs = uniq(dbs);

  var deleted = 0;
  var num = dbs.length;
  var errors = [];

  function dbDeleted(err, res) {
    // 400 is for an unexpected return from CouchDB, filed
    // https://issues.apache.org/jira/browse/COUCHDB-2205
    if (err && (err.status !== 404 && err.status !== 400)) {
      errors.push(err);
    }
    if (++deleted === num) {
      if (errors.length > 0) {
        // TODO: report all the errors
        done(errors[0]);
      } else {
        done();
      }
    }
  }

  dbs.forEach(function (db) {
    PouchDB.destroy(db, dbDeleted);
  });
};

// Put doc after prevRev (so that doc is a child of prevDoc
// in rev_tree). Doc must have _rev. If prevRev is not specified
// just insert doc with correct _rev (new_edits=false!)
testUtils.putAfter = function (db, doc, prevRev, callback) {
  var newDoc = PouchDB.extend({}, doc);
  if (!prevRev) {
    db.put(newDoc, { new_edits: false }, callback);
    return;
  }
  newDoc._revisions = {
    start: +newDoc._rev.split('-')[0],
    ids: [
      newDoc._rev.split('-')[1],
      prevRev.split('-')[1]
    ]
  };
  db.put(newDoc, { new_edits: false }, callback);
};

// docs will be inserted one after another
// starting from root
testUtils.putBranch = function (db, docs, callback) {
  function insert(i) {
    var doc = docs[i];
    var prev = i > 0 ? docs[i - 1]._rev : null;
    function next() {
      if (i < docs.length - 1) {
        insert(i + 1);
      } else {
        callback();
      }
    }
    db.get(doc._id, { rev: doc._rev }, function (err, ok) {
      if (err) {
        testUtils.putAfter(db, docs[i], prev, function (err, doc) {
          next();
        });
      } else {
        next();
      }
    });
  }
  insert(0);
};

testUtils.putTree = function (db, tree, callback) {
  function insert(i) {
    var branch = tree[i];
    testUtils.putBranch(db, branch, function () {
      if (i < tree.length - 1) {
        insert(i + 1);
      } else {
        callback();
      }
    });
  }
  insert(0);
};

testUtils.writeDocs = function (db, docs, callback, res) {
  if (!res) {
    res = [];
  }
  if (!docs.length) {
    return callback(null, res);
  }
  var doc = docs.shift();
  db.put(doc, function (err, info) {
    res.push(info);
    testUtils.writeDocs(db, docs, callback, res);
  });
};

// Borrowed from: http://stackoverflow.com/a/840849
testUtils.eliminateDuplicates = function (arr) {
  var i, element, len = arr.length, out = [], obj = {};
  for (i = 0; i < len; i++) {
    obj[arr[i]] = 0;
  }
  for (element in obj) {
    if (obj.hasOwnProperty(element)) {
      out.push(element);
    }
  }
  return out;
};

// ---- CORS Specific Utils ---- //
//enable CORS on server
testUtils.enableCORS = function (dburl, callback) {
  var host = 'http://' + dburl.split('/')[2] + '/';
  PouchDB.ajax({
    url: host + '_config/httpd/enable_cors',
    json: false,
    method: 'PUT',
    body: '"true"'
  }, function (err, resBody, req) {
    PouchDB.ajax({
      url: host + '_config/cors/origins',
      json: false,
      method: 'PUT',
      body: '"http://127.0.0.1:8000"'
    }, function (err, resBody, req) {
      callback(err, req);
    });
  });
};
//enable CORS Credentials on server
testUtils.enableCORSCredentials = function (dburl, callback) {
  var host = 'http://' + dburl.split('/')[2] + '/';
  PouchDB.ajax({
    url: host + '_config/cors/credentials',
    method: 'PUT',
    body: '"true"',
    json: false
  }, function (err, resBody, req) {
    callback(err, req);
  });
};
//disable CORS
testUtils.disableCORS = function (dburl, callback) {
  var host = 'http://' + dburl.split('/')[2] + '/';
  PouchDB.ajax({
    url: host + '_config/cors/origins',
    json: false,
    method: 'PUT',
    body: '"*"'
  }, function (err, resBody, req) {
    PouchDB.ajax({
      url: host + '_config/httpd/enable_cors',
      json: false,
      method: 'PUT',
      body: '"false"'
    }, function (err, resBody, req) {
      callback(err, req);
    });
  });
};
//disable CORS Credentials
testUtils.disableCORSCredentials = function (dburl, callback) {
  var host = 'http://' + dburl.split('/')[2] + '/';
  PouchDB.ajax({
    url: host + '_config/cors/credentials',
    method: 'PUT',
    body: '"false"',
    json: false
  }, function (err, resBody, req) {
    callback(err, req);
  });
};
//create admin user and member user
testUtils.setupAdminAndMemberConfig = function (dburl, callback) {
  var host = 'http://' + dburl.split('/')[2] + '/';
  PouchDB.ajax({
    url: host + '_users/org.couchdb.user:TestUser',
    method: 'PUT',
    body: {
      _id: 'org.couchdb.user:TestUser',
      name: 'TestUser',
      password: 'user',
      roles: [],
      type: 'user'
    }
  }, function (err, resBody, req) {
    PouchDB.ajax({
      url: host + '_config/admins/TestAdmin',
      json: false,
      method: 'PUT',
      body: '"admin"'
    }, function (err, resBody, req) {
      callback(err, req);
    });
  });
};
//delete admin and member user
testUtils.tearDownAdminAndMemberConfig = function (dburl, callback) {
  var host = 'http://' + dburl.split('/')[2] + '/';
  var headers = {};
  var token = btoa('TestAdmin:admin');
  headers.Authorization = 'Basic ' + token;
  PouchDB.ajax({
    url: host + '_config/admins/TestAdmin',
    method: 'DELETE',
    headers: headers,
    json: false
  }, function (err, resBody, req) {
    PouchDB.ajax({
      url: host + '_users/org.couchdb.user:TestUser',
      method: 'GET',
      body: '"admin"'
    }, function (err, resBody, req) {
      if (resBody) {
        PouchDB.ajax({
          url: host + '_users/org.couchdb.user:TestUser?rev=' + resBody._rev,
          method: 'DELETE',
          json: false
        }, function (err, resBody, req) {
          callback(err, req);
        });
      } else {
        callback(err, req);
      }
    });
  });
};
testUtils.deleteCookieAuth = function (dburl, callback_) {
  var host = 'http://' + dburl.split('/')[2] + '/';
  PouchDB.ajax({
    method: 'DELETE',
    url: host + '_session',
    withCredentials: true,
    json: false
  }, callback_);
};
testUtils.cleanUpCors = function (dburl, callback_) {
  if (testUtils.PERSIST_DATABASES) {
    return;
  }
  if (typeof module !== 'undefined' && module.exports) {
    testUtils.disableCORS(dburl, function () {
      PouchDB.destroy(dburl, callback_);
    });
  } else {
    testUtils.disableCORS(dburl.replace('5984', '2020'), function () {
      PouchDB.destroy(dburl.replace('5984', '2020'), callback_);
    });
  }
};
var testDir;
if (typeof module !== 'undefined' && module.exports) {
  global.PouchDB = require('../lib');
  if (process && process.env && process.env.LEVEL_ADAPTER) {
    global.PouchDB = global.PouchDB.defaults({
      db: require(process.env.LEVEL_ADAPTER)
    });
  }
  if (typeof process !== 'undefined') {
    testDir = process.env.TESTS_DIR ? process.env.TESTS_DIR : './tmp';
    testDir = testDir.slice(-1) === '/' ? testDir : testDir + '/';
    global.PouchDB.prefix = testDir + global.PouchDB.prefix;
    require('../lib/adapters/leveldb').use_prefix = true;
    require('bluebird').onPossiblyUnhandledRejection(function (e, promise) {
      throw e;
    });
  }
  module.exports = testUtils;
}