/*
 *
 *    Copyright (c) 2021 Project CHIP 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.
 */

// Import helpers from zap core
const zapPath           = '../../../../third_party/zap/repo/dist/src-electron/';
const queryConfig       = require(zapPath + 'db/query-config.js')
const queryCommand      = require(zapPath + 'db/query-command.js')
const queryEndpoint     = require(zapPath + 'db/query-endpoint.js')
const queryEndpointType = require(zapPath + 'db/query-endpoint-type.js')
const queryEvent        = require(zapPath + 'db/query-event.js')
const templateUtil      = require(zapPath + 'generator/template-util.js')
const zclHelper         = require(zapPath + 'generator/helper-zcl.js')
const zclQuery          = require(zapPath + 'db/query-zcl.js')

const { Deferred }    = require('./Deferred.js');
const ListHelper      = require('./ListHelper.js');
const StringHelper    = require('./StringHelper.js');
const ChipTypesHelper = require('./ChipTypesHelper.js');

// Helper for better error reporting.
function ensureState(condition, error)
{
  if (!condition) {
    let err = new Error(error);
    console.log(`${error}: ` + err.stack);
    throw err;
  }
}

//
// Load Step 1
//
function loadAtomics(packageId)
{
  const { db, sessionId } = this.global;
  const options           = { 'hash' : {} };

  const resolveZclTypes = atomics => Promise.all(atomics.map(atomic => {
    return zclHelper.asUnderlyingZclType.call(this, atomic.name, options).then(zclType => {
      atomic.chipType = zclType;
      return atomic;
    });
  }));

  return zclQuery.selectAllAtomics(db, packageId).then(resolveZclTypes);
}

function loadBitmaps(packageId)
{
  const { db, sessionId } = this.global;
  return zclQuery.selectAllBitmaps(db, packageId);
}

function loadEnums(packageId)
{
  const { db, sessionId } = this.global;
  return zclQuery.selectAllEnums(db, packageId);
}

function loadStructItems(struct, packageId)
{
  const { db, sessionId } = this.global;
  return zclQuery.selectAllStructItemsById(db, struct.id).then(structItems => {
    struct.items = structItems;
    return struct;
  });
}

function loadStructs(packageId)
{
  const { db, sessionId } = this.global;
  return zclQuery.selectAllStructsWithItemCount(db, packageId)
      .then(structs => Promise.all(structs.map(struct => loadStructItems.call(this, struct, packageId))));
}

/**
 * Loads endpoint data, specifically what endpoints are available and what clusters
 * are defined within those endpoints.
 */
async function loadEndpoints()
{
  let result = [];

  const { db, sessionId } = this.global;

  const endpoints = await queryEndpoint.selectAllEndpoints(db, sessionId);

  // Selection is one by one since existing API does not seem to provide
  // linkage between cluster and what endpoint it belongs to.
  //
  // TODO: there should be a better way
  for (const endpoint of endpoints) {
    const endpointClusters
        = await queryEndpointType.selectAllClustersDetailsFromEndpointTypes(db, [ { endpointTypeId : endpoint.endpointTypeRef } ]);
    result.push({...endpoint, clusters : endpointClusters.filter(c => c.enabled == 1) });
  }

  return result;
}

async function loadAllClusters(packageId)
{
  const { db, sessionId } = this.global;

  let allClusters = await zclQuery.selectAllClusters(db, packageId);
  // To match what loadClusters does, sort by cluster name (not cluster code).
  allClusters.sort((a, b) => {
    if (a.name < b.name) {
      return -1;
    }
    if (a.name == b.name) {
      return 0;
    }
    return 1;
  });
  let serverClusters = allClusters.map(cluster => ({...cluster, side : 'server', enabled : true }));
  let clientClusters = allClusters.map(cluster => ({...cluster, side : 'client', enabled : true }));
  return serverClusters.concat(clientClusters);
}

async function loadClusters()
{
  const { db, sessionId } = this.global;

  const endpointTypes = await queryEndpointType.selectEndpointTypeIds(db, sessionId);
  const clusters      = await queryEndpointType.selectAllClustersDetailsFromEndpointTypes(db, endpointTypes);

  return clusters.filter(cluster => cluster.enabled == 1);
}

function loadCommandResponse(command, packageId)
{
  const { db, sessionId } = this.global;
  return queryCommand.selectCommandById(db, command.id, packageId).then(commandDetails => {
    if (commandDetails.responseRef == null) {
      command.response = null;
      return command;
    }

    return queryCommand.selectCommandById(db, commandDetails.responseRef, packageId).then(response => {
      command.response = response;
      return command;
    });
  });
}

function loadCommandArguments(command, packageId)
{
  const { db, sessionId } = this.global;
  return queryCommand.selectCommandArgumentsByCommandId(db, command.id, packageId).then(commandArguments => {
    command.arguments = commandArguments;
    return command;
  });
}

async function loadAllCommands(packageId)
{
  const { db, sessionId } = this.global;
  let cmds                = await queryCommand.selectAllCommandsWithClusterInfo(db, [ packageId ]);
  // For each command, include it twice: once as outgoing for its source, once
  // as incoming for its destination.
  let outgoing = cmds.map(cmd => ({...cmd, incoming : false, outgoing : true, clusterSide : cmd.source }));
  let incoming = cmds.map(
      cmd => ({...cmd, incoming : true, outgoing : false, clusterSide : (cmd.source == 'server' ? 'client' : 'server') }));
  let commands = Promise.resolve(outgoing.concat(incoming));
  return loadCommandsCommon.call(this, packageId, commands);
}

function loadCommands(packageId)
{
  const { db, sessionId } = this.global;
  let cmds                = queryEndpointType.selectEndpointTypeIds(db, sessionId)
                 .then(endpointTypes => queryEndpointType.selectClustersAndEndpointDetailsFromEndpointTypes(db, endpointTypes))
                 .then(endpointTypesAndClusters => queryCommand.selectCommandDetailsFromAllEndpointTypesAndClusters(
                           db, endpointTypesAndClusters, true));

  return loadCommandsCommon.call(this, packageId, cmds);
}

// commandsPromise is a promise for an array of commands.
function loadCommandsCommon(packageId, commandsPromise)
{
  return commandsPromise.then(commands => Promise.all(commands.map(command => loadCommandResponse.call(this, command, packageId))))
      .then(commands => Promise.all(commands.map(command => loadCommandArguments.call(this, command, packageId))));
}

async function loadAllAttributes(packageId)
{
  // The 'server' side is enforced here, because the list of attributes is used to generate client global
  // commands to retrieve server side attributes.
  const { db, sessionId } = this.global;
  let attrs               = await zclQuery.selectAllAttributesBySide(db, 'server', [ packageId ]);
  const globalAttrs       = attrs.filter(attr => attr.clusterRef == null);
  // Exclude global attributes for now, since we will add them ourselves for
  // all clusters.
  attrs = attrs.filter(attr => attr.clusterRef != null);
  // selectAllAttributesBySide sets clusterRef, not clusterId, so manually
  // set the latter here.
  attrs.forEach(attr => attr.clusterId = attr.clusterRef);

  const clusters = await zclQuery.selectAllClusters(db, packageId);
  for (let cluster of clusters) {
    for (let globalAttr of globalAttrs) {
      attrs.push({...globalAttr, clusterId : cluster.id });
    }
  }
  // selectAllAttributesBySide includes optionality information, which we
  // don't want here, because the types of the attributes are not in fact
  // optionals for our purposes.
  attrs.forEach(attr => delete attr.isOptional);
  // Treat all attributes that could be reportable as reportable.
  attrs.forEach(attr => {
    if (attr.isReportable) {
      attr.includedReportable = true;
    }
  });
  return attrs.sort((a, b) => a.code - b.code);
}

function loadAttributes(packageId)
{
  // The 'server' side is enforced here, because the list of attributes is used to generate client global
  // commands to retrieve server side attributes.
  const { db, sessionId } = this.global;
  return queryEndpointType.selectEndpointTypeIds(db, sessionId)
      .then(endpointTypes => Promise.all(
                endpointTypes.map(({ endpointTypeId }) => queryEndpoint.selectEndpointClusters(db, endpointTypeId))))
      .then(clusters => clusters.flat())
      .then(clusters => Promise.all(
                clusters.map(({ clusterId, side, endpointTypeId }) => queryEndpoint.selectEndpointClusterAttributes(
                                 db, clusterId, 'server', endpointTypeId))))
      .then(attributes => attributes.flat())
      .then(attributes => attributes.filter(attribute => attribute.isIncluded))
      .then(attributes => attributes.sort((a, b) => a.code - b.code));
  //.then(attributes => Promise.all(attributes.map(attribute => types.typeSizeAttribute(db, packageId, attribute))
}

async function loadAllEvents(packageId)
{
  const { db, sessionId } = this.global;
  let clusters            = await zclQuery.selectAllClusters(db, packageId);
  return loadEventsCommon.call(this, packageId, clusters);
}

async function loadEvents(packageId)
{
  const { db, sessionId } = this.global;
  let clusters            = await queryEndpointType.selectEndpointTypeIds(db, sessionId)
                     .then(endpointTypes => Promise.all(
                               endpointTypes.map(({ endpointTypeId }) => queryEndpoint.selectEndpointClusters(db, endpointTypeId))))
                     .then(clusters => clusters.flat(3));
  return loadEventsCommon.call(this, packageId, clusters);
}

// clusters is an array of clusters (not a promise).
function loadEventsCommon(packageId, clusters)
{
  const { db, sessionId } = this.global;
  return queryEvent.selectAllEvents(db, packageId).then(events => {
    events.forEach(event => {
      const cluster = clusters.find(cluster => cluster.code == event.clusterCode);
      if (cluster) {
        event.clusterId   = cluster.clusterId;
        event.clusterName = cluster.name;
      }
    });
    return events.filter(event => clusters.find(cluster => cluster.code == event.clusterCode));
  });
}

function loadGlobalAttributes(packageId)
{
  const { db, sessionId } = this.global;
  return zclQuery.selectAllAttributes(db, packageId)
      .then(attributes => attributes.filter(attribute => attribute.clusterRef == null))
      .then(attributes => attributes.map(attribute => attribute.code));
}

//
// Load step 2
//

function asChipCallback(item)
{
  if (StringHelper.isOctetString(item.type)) {
    return { name : 'OctetString', type : 'const chip::ByteSpan' };
  }

  if (StringHelper.isCharString(item.type)) {
    return { name : 'CharString', type : 'const chip::CharSpan' };
  }

  if (item.isArray) {
    return { name : 'List', type : null };
  }

  const basicType = ChipTypesHelper.asBasicType(item.chipType);
  switch (basicType) {
  case 'int8_t':
  case 'int16_t':
  case 'int32_t':
  case 'int64_t':
    return { name : 'Int' + basicType.replace(/[^0-9]/g, '') + 's', type : basicType };
  case 'uint8_t':
  case 'uint16_t':
  case 'uint32_t':
  case 'uint64_t':
    return { name : 'Int' + basicType.replace(/[^0-9]/g, '') + 'u', type : basicType };
  case 'bool':
    return { name : 'Boolean', type : 'bool' };
  case 'float':
    return { name : 'Float', type : 'float' };
  case 'double':
    return { name : 'Double', type : 'double' };
  default:
    return { name : 'Unsupported', type : null };
  }
}

function getAtomic(atomics, type)
{
  return atomics.find(atomic => atomic.name == type.toLowerCase());
}

function getBitmap(bitmaps, type)
{
  return bitmaps.find(bitmap => bitmap.label == type);
}

function getEnum(enums, type)
{
  return enums.find(enumItem => enumItem.label == type);
}

function getStruct(structs, type)
{
  return structs.find(struct => struct.label == type);
}

function handleString(item, [ atomics, enums, bitmaps, structs ])
{
  if (!StringHelper.isString(item.type)) {
    return false;
  }

  const atomic = getAtomic(atomics, item.type);
  if (!atomic) {
    return false;
  }

  const kLengthSizeInBytes = 2;

  item.atomicTypeId = atomic.atomicId;
  if (StringHelper.isOctetString(item.type)) {
    item.chipType = 'chip::ByteSpan';
  } else {
    item.chipType = 'chip::CharSpan';
  }
  item.size = kLengthSizeInBytes + item.maxLength;
  item.name = item.name || item.label;
  return true;
}

function handleList(item, [ atomics, enums, bitmaps, structs ])
{
  if (!ListHelper.isList(item.type)) {
    return false;
  }

  const entryType = item.entryType;
  if (!entryType) {
    console.log(item);
    throw new Error(item.label, 'List[T] is missing type "T" information');
  }

  item.isArray = true;
  item.type    = entryType;
  enhancedItem(item, [ atomics, enums, bitmaps, structs ]);

  return true;
}

function handleStruct(item, [ atomics, enums, bitmaps, structs ])
{
  const struct = getStruct(structs, item.type);
  if (!struct) {
    return false;
  }

  // Add a leading `_` before the name of struct to match what is done in the af-structs.zapt template.
  // For instance structs are declared as "typedef struct _{{asType label}}".
  item.chipType = '_' + item.type;
  item.isStruct = true;

  struct.items.map(structItem => enhancedItem(structItem, [ atomics, enums, bitmaps, structs ]));
  item.items = struct.items;
  item.size  = struct.items.map(type => type.size).reduce((accumulator, currentValue) => accumulator + currentValue, 0);
  return true;
}

function handleBasic(item, [ atomics, enums, bitmaps, structs ])
{
  let itemType = item.type;

  const enumItem = getEnum(enums, itemType);
  if (enumItem) {
    item.isEnum = true;
    itemType    = 'enum' + enumItem.size * 8;
  }

  const bitmap = getBitmap(bitmaps, itemType);
  if (bitmap) {
    item.isBitmap = true;
    itemType      = 'bitmap' + bitmap.size * 8;
  }

  const atomic = getAtomic(atomics, itemType);
  if (atomic) {
    item.name         = item.name || item.label;
    item.isStruct     = false;
    item.atomicTypeId = atomic.atomicId;
    item.size         = atomic.size;
    item.chipType     = atomic.chipType;
    return true;
  }

  return false;
}

function enhancedItem(item, types)
{
  if (handleString(item, types)) {
    return;
  }

  if (handleList(item, types)) {
    return;
  }

  if (handleStruct(item, types)) {
    return;
  }

  if (handleBasic(item, types)) {
    return;
  }

  console.log(item);
  throw new Error(item.type + ' not found.');
}

function inlineStructItems(args)
{
  const arguments = [];
  args.forEach(argument => {
    if (!argument.isStruct) {
      arguments.push(argument);
      return;
    }

    argument.items.forEach(item => {
      arguments.push(item);
    });
  });

  return arguments;
}

function enhancedCommands(commands, types)
{
  commands.forEach(command => {
    command.arguments.forEach(argument => {
      enhancedItem(argument, types);
      argument.isComplex = argument.isList || argument.isStruct || argument.isArray;
    });
  });

  commands.forEach(command => {
    // Flag things ending in "Response" so we can filter out unused responses,
    // but don't stomp on a true isResponse value if it's set already because
    // some other command had this one as its response.
    command.isResponse                    = command.isResponse || command.name.includes('Response');
    command.isManufacturerSpecificCommand = !!this.mfgCode;

    command.hasSpecificResponse = !!command.response;
    if (command.response) {
      const responseName   = command.response.name;
      command.responseName = responseName;
      // The 'response' property contains the response returned by the `selectCommandById`
      // helper. But this one does not contains all the metadata informations added by
      // `enhancedItem`, so instead of using the one from ZAP, retrieve the enhanced version.
      command.response = commands.find(command => command.name == responseName);
      // We might have failed to find a response if our configuration is weird
      // in some way.
      if (command.response) {
        command.response.isResponse = true;
      }
    } else {
      command.responseName = 'DefaultSuccess';
      command.response     = { arguments : [] };
    }
  });

  // Filter unused responses
  commands = commands.filter(command => {
    if (!command.isResponse) {
      return true;
    }

    const responseName = command.name;
    return commands.find(command => command.responseName == responseName);
  });

  // At this stage, 'command.arguments' may contains 'struct'. But some controllers does not know (yet) how
  // to handle them. So those needs to be inlined.
  commands.forEach(command => {
    if (command.isResponse) {
      return;
    }

    command.expandedArguments = inlineStructItems(command.arguments);
  });

  return commands;
}

function enhancedEvents(events, types)
{
  events.forEach(event => {
    const argument = {
      name : event.name,
      type : event.name,
      isArray : false,
      isEvent : true,
      isNullable : false,
      label : event.name,
    };
    event.response = { arguments : [ argument ] };
  });
  return events;
}

function enhancedAttributes(attributes, globalAttributes, types)
{
  attributes.forEach(attribute => {
    enhancedItem(attribute, types);
    attribute.isGlobalAttribute     = globalAttributes.includes(attribute.code);
    attribute.isWritableAttribute   = !!attribute.isWritable;
    attribute.isReportableAttribute = !!attribute.includedReportable;
    attribute.chipCallback          = asChipCallback(attribute);
    attribute.isComplex             = attribute.isList || attribute.isStruct || attribute.isArray;
  });

  attributes.forEach(attribute => {
    const argument = {
      name : attribute.name,
      type : attribute.type,
      size : attribute.size,
      isArray : attribute.isArray,
      isEvent : false,
      isNullable : attribute.isNullable,
      chipType : attribute.chipType,
      chipCallback : attribute.chipCallback,
      label : attribute.name,
    };
    attribute.arguments = [ argument ];
    attribute.response  = { arguments : [ argument ] };
  });

  // At this stage, the 'attributes' array contains all attributes enabled for all endpoints. It means
  // that a lot of attributes are duplicated if a cluster is enabled on multiple endpoints but that's
  // not what the templates expect. So let's deduplicate them.
  const compare = (a, b) => (a.name == b.name && a.clusterId == b.clusterId && a.side == b.side);
  return attributes.filter((att, index) => attributes.findIndex(att2 => compare(att, att2)) == index);
}

const Clusters = {
  ready : new Deferred(),
  post_processing_ready : new Deferred()
};

class ClusterStructUsage {
  constructor()
  {
    this.usedStructures       = new Map(); // Structure label -> structure
    this.clustersForStructure = new Map(); // Structure label -> Set(Cluster name)
    this.structuresForCluster = new Map(); // Cluster name -> Set(Structure label)
  }

  addUsedStructure(clusterName, structure)
  {
    // Record that generally this structure is used
    this.usedStructures.set(structure.label, structure);

    // Record that this structure is used by a
    // particular cluster name
    let clusterSet = this.clustersForStructure.get(structure.label);
    if (!clusterSet) {
      clusterSet = new Set();
      this.clustersForStructure.set(structure.label, clusterSet);
    }
    clusterSet.add(clusterName);

    let structureLabelSet = this.structuresForCluster.get(clusterName);
    if (!structureLabelSet) {
      structureLabelSet = new Set();
      this.structuresForCluster.set(clusterName, structureLabelSet);
    }
    structureLabelSet.add(structure.label);
  }

  /**
   * Finds structures that are specific to one cluster:
   *   - they belong to the cluster
   *   - only that cluster ever uses it
   */
  structuresSpecificToCluster(clusterName)
  {
    let clusterStructures = this.structuresForCluster.get(clusterName);
    if (!clusterStructures) {
      return [];
    }

    return Array.from(clusterStructures)
        .filter(name => this.clustersForStructure.get(name).size == 1)
        .map(name => this.usedStructures.get(name));
  }

  structuresUsedByMultipleClusters()
  {
    return Array.from(this.usedStructures.values()).filter(s => this.clustersForStructure.get(s.label).size > 1);
  }
}

Clusters._addUsedStructureNames = async function(clusterName, startType, allKnownStructs) {
  const struct = getStruct(allKnownStructs, startType.type);
  if (!struct) {
    return;
  }

  this._cluster_structures.addUsedStructure(clusterName, struct);

  for (const item of struct.items) {
    this._addUsedStructureNames(clusterName, item, allKnownStructs);
  }
}

Clusters._computeUsedStructureNames = async function(structs) {
  // NOTE: this MUST be called only after attribute promise is resolved
  // as iteration of `get*ByClusterName` needs that data.
  for (const cluster of this._clusters) {
    const attributes = await this.getAttributesByClusterName(cluster.name);
    for (const attribute of attributes) {
      if (attribute.isStruct) {
        this._addUsedStructureNames(cluster.name, attribute, structs);
      }
    }

    const commands = await this.getCommandsByClusterName(cluster.name);
    for (const command of commands) {
      for (const argument of command.arguments) {
        this._addUsedStructureNames(cluster.name, argument, structs);
      }
    }

    const responses = await this.getResponsesByClusterName(cluster.name);
    for (const response of responses) {
      for (const argument of response.arguments) {
        this._addUsedStructureNames(cluster.name, argument, structs);
      }
    }
  }

  this._used_structure_names = new Set(this._cluster_structures.usedStructures.keys())
}

/**
 * If includeAll is true, all events/commands/attributes will be included, not
 * just the ones enabled in the ZAP configuration.
 */
Clusters.init = async function(context, includeAll) {
  if (this.ready.running)
  {
    return this.ready;
  }
  this.ready.running = true;

  let packageId = await templateUtil.ensureZclPackageId(context).catch(err => { console.log(err); throw err; });

  const loadTypes = [
    loadAtomics.call(context, packageId),
    loadEnums.call(context, packageId),
    loadBitmaps.call(context, packageId),
    loadStructs.call(context, packageId),
  ];

  const promises = [
    Promise.all(loadTypes),
    loadEndpoints.call(context),
    // For now just always use loadClusters, because we have a bunch of things
    // defined in our XML that are not actually part of Matter.
    (includeAll ? loadClusters : loadClusters).call(context, packageId),
    (includeAll ? loadAllCommands : loadCommands).call(context, packageId),
    (includeAll ? loadAllAttributes : loadAttributes).call(context, packageId),
    loadGlobalAttributes.call(context, packageId),
    (includeAll ? loadAllEvents : loadEvents).call(context, packageId),
  ];

  let [types, endpoints, clusters, commands, attributes, globalAttributes, events] = await Promise.all(promises);

  this._endpoints = endpoints;
  this._clusters = clusters;
  this._commands = enhancedCommands(commands, types);
  this._attributes = enhancedAttributes(attributes, globalAttributes, types);
  this._events = enhancedEvents(events, types);
  this._cluster_structures = new ClusterStructUsage();

  // data is ready, but not full post - processing
  this.ready.resolve();

  await this._computeUsedStructureNames(types[3]);

  return this.post_processing_ready.resolve();
}


//
// Helpers: All
//
function asBlocks(promise, options)
{
  return promise.then(data => templateUtil.collectBlocks(data, options, this))
}

function ensureClusters(context, includeAll = false)
{
  // Kick off Clusters initialization.  This is async, but that's fine: all the
  // getters on Clusters wait on that initialziation to complete.
  ensureState(context, "Don't have a context");

  Clusters.init(context, includeAll);
  return Clusters;
}

//
// Helpers: Get all clusters/commands/responses/attributes.
//
const kResponseFilter = (isResponse, item) => isResponse == item.isResponse;

Clusters.ensureReady = function()
{
    ensureState(this.ready.running);
    return this.ready;
}

Clusters.ensurePostProcessingDone = function()
{
    ensureState(this.ready.running);
    return this.post_processing_ready;
}

Clusters.getClusters = function()
{
    return this.ensureReady().then(() => this._clusters);
}

Clusters.getEndPoints = function()
{
    return this.ensureReady().then(() => this._endpoints);
}

Clusters.getCommands = function()
{
    return this.ensureReady().then(() => this._commands.filter(kResponseFilter.bind(null, false)));
}

Clusters.getResponses = function()
{
    return this.ensureReady().then(() => this._commands.filter(kResponseFilter.bind(null, true)));
}

Clusters.getAttributes = function()
{
    return this.ensureReady().then(() => this._attributes);
}

Clusters.getEvents = function()
{
    return this.ensureReady().then(() => this._events);
}

//
// Helpers: Get by Cluster Name
//
const kNameFilter = (name, item) => name.toLowerCase() == (item.clusterName || item.name).toLowerCase();

Clusters.getCommandsByClusterName = function(name)
{
    return this.getCommands().then(items => items.filter(kNameFilter.bind(null, name)));
}

Clusters.getResponsesByClusterName = function(name)
{
    return this.getResponses().then(items => items.filter(kNameFilter.bind(null, name)));
}

Clusters.getAttributesByClusterName = function(name)
{
    return this.ensureReady().then(() => {
      const clusterId = this._clusters.find(kNameFilter.bind(null, name)).id;
      const filter = attribute => attribute.clusterId == clusterId;
      return this.getAttributes().then(items => items.filter(filter));
    });
}

Clusters.getEventsByClusterName = function(name)
{
    return this.getEvents().then(items => items.filter(kNameFilter.bind(null, name)));
}

//
// Helpers: Get by Cluster Side
//
const kSideFilter = (side, item) => item.source ? ((item.source == side && item.outgoing) || (item.source != side && item.incoming))
                                                : item.side == side;

Clusters.getCommandsByClusterSide = function(side)
{
    return this.getCommands().then(items => items.filter(kSideFilter.bind(null, side)));
}

Clusters.getResponsesByClusterSide = function(side)
{
    return this.getResponses().then(items => items.filter(kSideFilter.bind(null, side)));
}

Clusters.getAttributesByClusterSide = function(side)
{
    return this.getAttributes().then(items => items.filter(kSideFilter.bind(null, side)));
}

Clusters.getEventsByClusterSide = function(side)
{
    return this.getEvents().then(items => items.filter(kSideFilter.bind(null, side)));
}


//
// Helpers: Client
//
const kClientSideFilter = kSideFilter.bind(null, 'client');

Clusters.getClientClusters = function()
{
    return this.getClusters().then(items => items.filter(kClientSideFilter));
}

Clusters.getClientCommands = function(name)
{
    return this.getCommandsByClusterName(name).then(items => items.filter(kClientSideFilter));
}

Clusters.getClientResponses = function(name)
{
    return this.getResponsesByClusterName(name).then(items => items.filter(kClientSideFilter));
}

Clusters.getClientAttributes = function(name)
{
    return this.getAttributesByClusterName(name).then(items => items.filter(kClientSideFilter));
}

Clusters.getClientEvents = function(name)
{
    return this.getEventsByClusterName(name).then(items => items.filter(kClientSideFilter));
}

//
// Helpers: Server
//
const kServerSideFilter = kSideFilter.bind(null, 'server');

Clusters.getServerClusters = function()
{
    return this.getClusters().then(items => items.filter(kServerSideFilter));
}

Clusters.getServerCommands = function(name)
{
    return this.getCommandsByClusterName(name).then(items => items.filter(kServerSideFilter));
}

Clusters.getServerResponses = function(name)
{
    return this.getResponsesByClusterName(name).then(items => items.filter(kServerSideFilter));
}

Clusters.getServerAttributes = function(name)
{
    return this.getAttributesByClusterName(name).then(items => items.filter(kServerSideFilter));
}

Clusters.getUsedStructureNames = function()
{
    return this.ensurePostProcessingDone().then(() => this._used_structure_names);
}

Clusters.getStructuresByClusterName = function(name)
{
    return this.ensurePostProcessingDone().then(() => this._cluster_structures.structuresSpecificToCluster(name));
}

Clusters.getSharedStructs = function()
{
    return this.ensurePostProcessingDone().then(() => this._cluster_structures.structuresUsedByMultipleClusters());
}

Clusters.getServerEvents = function(name)
{
    return this.getEventsByClusterName(name).then(items => items.filter(kServerSideFilter));
}

//
// Module exports
//
exports.asBlocks = asBlocks;
exports.ensureClusters = ensureClusters;