import produce, { Draft } from 'immer';
import pluginServiceReducer, { stateRootKey as pluginServiceStateRootKey, defaultState as pluginServiceDefaultState, State as PluginServiceState } from 'lib/services/plugins/reducer';
const Note = require('lib/models/Note.js');
const Folder = require('lib/models/Folder.js');
const BaseModel = require('lib/BaseModel');
const ArrayUtils = require('lib/ArrayUtils.js');
const { ALL_NOTES_FILTER_ID } = require('lib/reserved-ids');
const { createSelectorCreator, defaultMemoize } = require('reselect');
const { createCachedSelector } = require('re-reselect');

const additionalReducers:any[] = [];

additionalReducers.push({
	stateRootKey: pluginServiceStateRootKey,
	defaultState: pluginServiceDefaultState,
	reducer: pluginServiceReducer,
});

interface StateLastSelectedNotesIds {
	Folder: any,
	Tag: any,
	Search: any,
}

interface StateClipperServer {
	startState: string,
	port: number,
}

interface StateDecryptionWorker {
	state: string,
	itemIndex: number,
	itemCount: number,
	decryptedItemCounts: any
	decryptedItemCount: number,
	skippedItemCount: number,
}

interface StateResourceFetcher {
	toFetchCount: number,
}

export interface State {
	notes: any[],
	notesSource: string,
	notesParentType: string,
	folders: any[],
	tags: any[],
	masterKeys: any[],
	notLoadedMasterKeys: any[],
	searches: any[],
	highlightedWords: string[],
	selectedNoteIds: string[],
	selectedNoteHash: string,
	selectedFolderId: string,
	selectedTagId: string,
	selectedSearchId: string,
	selectedItemType: string,
	selectedSmartFilterId: string,
	lastSelectedNotesIds: StateLastSelectedNotesIds,
	showSideMenu: boolean,
	screens: any
	historyCanGoBack: boolean,
	syncStarted: boolean,
	syncReport: any
	searchQuery: string,
	settings: any
	sharedData: any,
	appState: string,
	hasDisabledSyncItems: boolean,
	hasDisabledEncryptionItems: boolean,
	customCss: string,
	templates: any[],
	collapsedFolderIds: string[],
	clipperServer: StateClipperServer,
	decryptionWorker: StateDecryptionWorker,
	selectedNoteTags: any[],
	resourceFetcher: StateResourceFetcher,
	backwardHistoryNotes: any[],
	forwardHistoryNotes: any[],
	pluginsLegacy: any
	provisionalNoteIds: string[],
	editorNoteStatuses: any
	isInsertingNotes: boolean,
	hasEncryptedItems: boolean,

	// Extra reducer keys go here:
	pluginService: PluginServiceState,
}

export const defaultState:State = {
	notes: [],
	notesSource: '',
	notesParentType: null,
	folders: [],
	tags: [],
	masterKeys: [],
	notLoadedMasterKeys: [],
	searches: [],
	highlightedWords: [],
	selectedNoteIds: [],
	selectedNoteHash: '',
	selectedFolderId: null,
	selectedTagId: null,
	selectedSearchId: null,
	selectedSmartFilterId: null,
	selectedItemType: 'note',
	lastSelectedNotesIds: {
		Folder: {},
		Tag: {},
		Search: {},
	},
	showSideMenu: false,
	screens: {},
	historyCanGoBack: false,
	syncStarted: false,
	syncReport: {},
	searchQuery: '',
	settings: {},
	sharedData: null,
	appState: 'starting',
	hasDisabledSyncItems: false,
	hasDisabledEncryptionItems: false,
	customCss: '',
	templates: [],
	collapsedFolderIds: [],
	clipperServer: {
		startState: 'idle',
		port: null,
	},
	decryptionWorker: {
		state: 'idle',
		itemIndex: 0,
		itemCount: 0,
		decryptedItemCounts: {},
		decryptedItemCount: 0,
		skippedItemCount: 0,
	},
	selectedNoteTags: [],
	resourceFetcher: {
		toFetchCount: 0,
	},
	backwardHistoryNotes: [],
	forwardHistoryNotes: [],
	// pluginsLegacy is the original plugin system, which eventually was used only for GotoAnything.
	// GotoAnything should be refactored to part of core and when it's done the pluginsLegacy key can
	// be removed. It was originally named "plugins", then renamed "pluginsLegacy" so as not to conflict
	// with the new "plugins" key used for the new plugin system.
	pluginsLegacy: {},
	provisionalNoteIds: [],
	editorNoteStatuses: {},
	isInsertingNotes: false,
	hasEncryptedItems: false,

	pluginService: pluginServiceDefaultState,
};

for (const additionalReducer of additionalReducers) {
	(defaultState as any)[additionalReducer.stateRootKey] = additionalReducer.defaultState;
}

export const MAX_HISTORY = 200;

const derivedStateCache_:any = {};

// Allows, for a given state, to return the same derived
// objects, to prevent unecessary updates on calling components.
const cacheEnabledOutput = (key:string, output:any) => {
	key = `${key}_${JSON.stringify(output)}`;
	if (derivedStateCache_[key]) return derivedStateCache_[key];

	derivedStateCache_[key] = output;
	return derivedStateCache_[key];
};

const createShallowArrayEqualSelector = createSelectorCreator(
	defaultMemoize,
	(prev:any[], next:any[]) => {
		if (prev.length !== next.length) return false;
		for (let i = 0; i < prev.length; i++) {
			if (prev[i] !== next[i]) return false;
		}
		return true;
	}
);

const selectArrayShallow = createCachedSelector(
	(state:any) => state.array,
	(array:any[]) => array
)({
	keySelector: (_state:any, cacheKey:any) => {
		return cacheKey;
	},
	selectorCreator: createShallowArrayEqualSelector,
});

class StateUtils {

	// Given an input array, this selector ensures that the same array is returned
	// if its content hasn't changed.
	public selectArrayShallow(props:any, cacheKey:any) {
		return selectArrayShallow(props, cacheKey);
	}

	public oneNoteSelected(state:State):boolean {
		return state.selectedNoteIds.length === 1;
	}

	public notesOrder(stateSettings:any) {
		if (stateSettings['notes.sortOrder.field'] === 'order') {
			return cacheEnabledOutput('notesOrder', [
				{
					by: 'order',
					dir: 'DESC',
				},
				{
					by: 'user_created_time',
					dir: 'DESC',
				},
			]);
		} else {
			return cacheEnabledOutput('notesOrder', [
				{
					by: stateSettings['notes.sortOrder.field'],
					dir: stateSettings['notes.sortOrder.reverse'] ? 'DESC' : 'ASC',
				},
			]);
		}
	}

	public foldersOrder(stateSettings:any) {
		return cacheEnabledOutput('foldersOrder', [
			{
				by: stateSettings['folders.sortOrder.field'],
				dir: stateSettings['folders.sortOrder.reverse'] ? 'DESC' : 'ASC',
			},
		]);
	}

	public hasNotesBeingSaved(state:State):boolean {
		for (const id in state.editorNoteStatuses) {
			if (state.editorNoteStatuses[id] === 'saving') return true;
		}
		return false;
	}

	public parentItem(state:State) {
		const t = state.notesParentType;
		let id = null;
		if (t === 'Folder') id = state.selectedFolderId;
		if (t === 'Tag') id = state.selectedTagId;
		if (t === 'Search') id = state.selectedSearchId;
		if (!t || !id) return null;
		return { type: t, id: id };
	}

	public lastSelectedNoteIds(state:State):string[] {
		const parent = this.parentItem(state);
		if (!parent) return [];
		const output = (state.lastSelectedNotesIds as any)[parent.type][parent.id];
		return output ? output : [];
	}

	public selectedNote(state:State):any {
		const noteId = this.selectedNoteId(state);
		return noteId ? BaseModel.byId(state.notes, noteId) : null;
	}

	public selectedNoteId(state:State):any {
		return state.selectedNoteIds.length ? state.selectedNoteIds[0] : null;
	}

}

export const stateUtils:StateUtils = new StateUtils();

function arrayHasEncryptedItems(array:any[]) {
	for (let i = 0; i < array.length; i++) {
		if (array[i].encryption_applied) return true;
	}
	return false;
}

function stateHasEncryptedItems(state:State) {
	if (arrayHasEncryptedItems(state.notes)) return true;
	if (arrayHasEncryptedItems(state.folders)) return true;
	if (arrayHasEncryptedItems(state.tags)) return true;
	return false;
}

function folderSetCollapsed(draft:Draft<State>, action:any) {
	const collapsedFolderIds = draft.collapsedFolderIds.slice();
	const idx = collapsedFolderIds.indexOf(action.id);

	if (action.collapsed) {
		if (idx >= 0) return;
		collapsedFolderIds.push(action.id);
	} else {
		if (idx < 0) return;
		collapsedFolderIds.splice(idx, 1);
	}

	draft.collapsedFolderIds = collapsedFolderIds;
}

function removeAdjacentDuplicates(items:any[]) {
	return items.filter((item:any, idx:number) => (idx >= 1) ? items[idx - 1].id !== item.id : true);
}

// When deleting a note, tag or folder
function handleItemDelete(draft:Draft<State>, action:any) {
	const map:any = {
		FOLDER_DELETE: ['folders', 'selectedFolderId', true],
		NOTE_DELETE: ['notes', 'selectedNoteIds', false],
		TAG_DELETE: ['tags', 'selectedTagId', true],
		SEARCH_DELETE: ['searches', 'selectedSearchId', true],
	};

	const listKey = map[action.type][0];
	const selectedItemKey = map[action.type][1];
	const isSingular = map[action.type][2];

	const selectedItemKeys = isSingular ? [(draft as any)[selectedItemKey]] : (draft as any)[selectedItemKey];
	const isSelected = selectedItemKeys.includes(action.id);

	const items = (draft as any)[listKey];
	const newItems = [];
	let newSelectedIndexes:number[] = [];

	for (let i = 0; i < items.length; i++) {
		const item = items[i];
		if (isSelected) {
			// the selected item is deleted so select the following item
			// if multiple items are selected then just use the first one
			if (selectedItemKeys[0] == item.id) {
				newSelectedIndexes.push(newItems.length);
			}
		} else {
			// the selected item/s is not deleted so keep it selected
			if (selectedItemKeys.includes(item.id)) {
				newSelectedIndexes.push(newItems.length);
			}
		}
		if (item.id == action.id) {
			continue;
		}
		newItems.push(item);
	}

	if (newItems.length == 0) {
		newSelectedIndexes = []; // no remaining items so no selection

	}  else if (newSelectedIndexes.length == 0) {
		newSelectedIndexes.push(0); // no selection exists so select the top

	} else {
		// when the items at end of list are deleted then select the end
		for (let i = 0; i < newSelectedIndexes.length; i++) {
			if (newSelectedIndexes[i] >= newItems.length) {
				newSelectedIndexes = [newItems.length - 1];
				break;
			}
		}
	}

	(draft as any)[listKey] = newItems;

	const newIds = [];
	for (let i = 0; i < newSelectedIndexes.length; i++) {
		newIds.push(newItems[newSelectedIndexes[i]].id);
	}
	(draft as any)[selectedItemKey] = isSingular ? newIds[0] : newIds;

	if ((newIds.length == 0) && draft.notesParentType !== 'Folder') {
		draft.notesParentType = 'Folder';
	}
}

function updateOneItem(draft:Draft<State>, action:any, keyName:string = '') {
	let itemsKey = null;
	if (keyName) { itemsKey = keyName; } else {
		if (action.type === 'TAG_UPDATE_ONE') itemsKey = 'tags';
		if (action.type === 'FOLDER_UPDATE_ONE') itemsKey = 'folders';
		if (action.type === 'MASTERKEY_UPDATE_ONE') itemsKey = 'masterKeys';
	}

	const newItems = (draft as any)[itemsKey].slice();
	const item = action.item;

	let found = false;
	for (let i = 0; i < newItems.length; i++) {
		const n = newItems[i];
		if (n.id == item.id) {
			newItems[i] = Object.assign({}, newItems[i], item);
			found = true;
			break;
		}
	}

	if (!found) newItems.push(item);

	(draft as any)[itemsKey] = newItems;
}

function updateSelectedNotesFromExistingNotes(draft:Draft<State>) {
	const newSelectedNoteIds = [];
	for (const selectedNoteId of draft.selectedNoteIds) {
		for (const n of draft.notes) {
			if (n.id === selectedNoteId) {
				newSelectedNoteIds.push(n.id);
			}
		}
	}

	draft.selectedNoteIds = newSelectedNoteIds;
}

function defaultNotesParentType(draft:Draft<State>, exclusion:string) {
	let newNotesParentType = null;

	if (exclusion !== 'SmartFilter' && draft.selectedSmartFilterId) {
		newNotesParentType = 'SmartFilter';
	} else if (exclusion !== 'Folder' && draft.selectedFolderId) {
		newNotesParentType = 'Folder';
	} else if (exclusion !== 'Tag' && draft.selectedTagId) {
		newNotesParentType = 'Tag';
	} else if (exclusion !== 'Search' && draft.selectedSearchId) {
		newNotesParentType = 'Search';
	}

	return newNotesParentType;
}

function changeSelectedFolder(draft:Draft<State>, action:any, options:any = null) {
	if (!options) options = {};
	draft.selectedFolderId = 'folderId' in action ? action.folderId : action.id;
	if (!draft.selectedFolderId) {
		draft.notesParentType = defaultNotesParentType(draft, 'Folder');
	} else {
		draft.notesParentType = 'Folder';
	}

	if (options.clearSelectedNoteIds) draft.selectedNoteIds = [];
}

function recordLastSelectedNoteIds(draft:Draft<State>, noteIds:string[]) {
	const newOnes:any = Object.assign({}, draft.lastSelectedNotesIds);
	const parent = stateUtils.parentItem(draft);
	if (!parent) return;

	newOnes[parent.type] = Object.assign({}, newOnes[parent.type]);
	newOnes[parent.type][parent.id] = noteIds.slice();

	draft.lastSelectedNotesIds = newOnes;
}

function changeSelectedNotes(draft:Draft<State>, action:any, options:any = null) {
	if (!options) options = {};

	let noteIds = [];
	if (action.id) noteIds = [action.id];
	if (action.ids) noteIds = action.ids;
	if (action.noteId) noteIds = [action.noteId];

	if (action.type === 'NOTE_SELECT') {
		if (JSON.stringify(draft.selectedNoteIds) === JSON.stringify(noteIds)) return;
		draft.selectedNoteIds = noteIds;
		draft.selectedNoteHash = action.hash ? action.hash : '';
	} else if (action.type === 'NOTE_SELECT_ADD') {
		if (!noteIds.length) return;
		draft.selectedNoteIds = ArrayUtils.unique(draft.selectedNoteIds.concat(noteIds));
	} else if (action.type === 'NOTE_SELECT_REMOVE') {
		if (!noteIds.length) return; // Nothing to unselect
		if (draft.selectedNoteIds.length <= 1) return; // Cannot unselect the last note

		const newSelectedNoteIds = [];
		for (let i = 0; i < draft.selectedNoteIds.length; i++) {
			const id = draft.selectedNoteIds[i];
			if (noteIds.indexOf(id) >= 0) continue;
			newSelectedNoteIds.push(id);
		}
		draft.selectedNoteIds = newSelectedNoteIds;
	} else if (action.type === 'NOTE_SELECT_TOGGLE') {
		if (!noteIds.length) return;

		if (draft.selectedNoteIds.indexOf(noteIds[0]) >= 0) {
			changeSelectedNotes(draft, { type: 'NOTE_SELECT_REMOVE', id: noteIds[0] });
		} else {
			changeSelectedNotes(draft, { type: 'NOTE_SELECT_ADD', id: noteIds[0] });
		}
	} else {
		throw new Error('Unreachable');
	}

	recordLastSelectedNoteIds(draft, draft.selectedNoteIds);
}

function removeItemFromArray(array:any[], property:any, value:any) {
	for (let i = 0; i !== array.length; ++i) {
		const currentItem = array[i];
		if (currentItem[property] === value) {
			array = array.slice();
			array.splice(i, 1);
			break;
		}
	}
	return array;
}

const getContextFromHistory = (ctx:any) => {
	const result:any = {};
	result.notesParentType = ctx.notesParentType;
	if (result.notesParentType === 'Folder') {
		result.selectedFolderId = ctx.selectedFolderId;
	} else if (result.notesParentType === 'Tag') {
		result.selectedTagId = ctx.selectedTagId;
	} else if (result.notesParentType === 'Search') {
		result.selectedSearchId = ctx.selectedSearchId;
		result.searches = ctx.searches;
	} else if (result.notesParentType === 'SmartFilter') {
		result.selectedSmartFilterId = ctx.selectedSmartFilterId;
	}
	return result;
};

function getNoteHistoryInfo(state:State) {
	const selectedNoteIds = state.selectedNoteIds;
	const notes = state.notes;
	if (selectedNoteIds != null && selectedNoteIds.length > 0) {
		const currNote = notes.find(note => note.id === selectedNoteIds[0]);
		if (currNote != null) {
			return {
				id: currNote.id,
				parent_id: currNote.parent_id,
				notesParentType: state.notesParentType,
				selectedFolderId: state.selectedFolderId,
				selectedTagId: state.selectedTagId,
				selectedSearchId: state.selectedSearchId,
				searches: state.searches,
				selectedSmartFilterId: state.selectedSmartFilterId,
			};
		}
	}
	return null;
}

function handleHistory(draft:Draft<State>, action:any) {
	const currentNote = getNoteHistoryInfo(draft);
	switch (action.type) {
	case 'HISTORY_BACKWARD': {
		const note = draft.backwardHistoryNotes[draft.backwardHistoryNotes.length - 1];
		if (currentNote != null && (draft.forwardHistoryNotes.length === 0 || currentNote.id != draft.forwardHistoryNotes[draft.forwardHistoryNotes.length - 1].id)) {
			draft.forwardHistoryNotes = draft.forwardHistoryNotes.concat(currentNote).slice(-MAX_HISTORY);
		}

		changeSelectedFolder(draft, Object.assign({}, action, { type: 'FOLDER_SELECT', folderId: note.parent_id }));
		changeSelectedNotes(draft, Object.assign({}, action, { type: 'NOTE_SELECT', noteId: note.id }));

		const ctx = draft.backwardHistoryNotes[draft.backwardHistoryNotes.length - 1];
		Object.assign(draft, getContextFromHistory(ctx));

		draft.backwardHistoryNotes.pop();
		break;
	}
	case 'HISTORY_FORWARD': {
		const note = draft.forwardHistoryNotes[draft.forwardHistoryNotes.length - 1];

		if (currentNote != null && (draft.backwardHistoryNotes.length === 0 || currentNote.id != draft.backwardHistoryNotes[draft.backwardHistoryNotes.length - 1].id)) {
			draft.backwardHistoryNotes = draft.backwardHistoryNotes.concat(currentNote).slice(-MAX_HISTORY);
		}

		changeSelectedFolder(draft, Object.assign({}, action, { type: 'FOLDER_SELECT', folderId: note.parent_id }));
		changeSelectedNotes(draft, Object.assign({}, action, { type: 'NOTE_SELECT', noteId: note.id }));

		const ctx = draft.forwardHistoryNotes[draft.forwardHistoryNotes.length - 1];
		Object.assign(draft, getContextFromHistory(ctx));


		draft.forwardHistoryNotes.pop();
		break;
	}
	case 'NOTE_SELECT':
		if (currentNote != null &&  action.id != currentNote.id) {
			draft.forwardHistoryNotes = [];
			draft.backwardHistoryNotes = draft.backwardHistoryNotes.concat(currentNote).slice(-MAX_HISTORY);
		}
		// History should be free from duplicates.
		if (draft.backwardHistoryNotes != null && draft.backwardHistoryNotes.length > 0 &&
						action.id === draft.backwardHistoryNotes[draft.backwardHistoryNotes.length - 1].id) {
			draft.backwardHistoryNotes.pop();
		}
		break;
	case 'TAG_SELECT':
	case 'FOLDER_AND_NOTE_SELECT':
	case 'FOLDER_SELECT':
		if (currentNote != null) {
			if (draft.forwardHistoryNotes.length) draft.forwardHistoryNotes = [];
			draft.backwardHistoryNotes = draft.backwardHistoryNotes.concat(currentNote).slice(-MAX_HISTORY);
		}
		break;
	case 'NOTE_UPDATE_ONE': {
		const modNote = action.note;

		draft.backwardHistoryNotes = draft.backwardHistoryNotes.map(note => {
			if (note.id === modNote.id) {
				return Object.assign({}, note, { parent_id: modNote.parent_id, selectedFolderId: modNote.parent_id });
			}
			return note;
		});

		draft.forwardHistoryNotes = draft.forwardHistoryNotes.map(note => {
			if (note.id === modNote.id) {
				return Object.assign({}, note, { parent_id: modNote.parent_id, selectedFolderId: modNote.parent_id });
			}
			return note;
		});

		break;
	}
	case 'SEARCH_UPDATE':
		if (currentNote != null && (draft.backwardHistoryNotes.length === 0 ||
						draft.backwardHistoryNotes[draft.backwardHistoryNotes.length - 1].id != currentNote.id)) {
			if (draft.forwardHistoryNotes.length) draft.forwardHistoryNotes = [];
			draft.backwardHistoryNotes = draft.backwardHistoryNotes.concat(currentNote).slice(-MAX_HISTORY);
		}
		break;
	case 'FOLDER_DELETE':
		draft.backwardHistoryNotes = draft.backwardHistoryNotes.filter(note => note.parent_id != action.id);
		draft.forwardHistoryNotes = draft.forwardHistoryNotes.filter(note => note.parent_id != action.id);

		draft.backwardHistoryNotes = removeAdjacentDuplicates(draft.backwardHistoryNotes);
		draft.forwardHistoryNotes = removeAdjacentDuplicates(draft.forwardHistoryNotes);
		break;
	case 'NOTE_DELETE': {
		draft.backwardHistoryNotes = draft.backwardHistoryNotes.filter(note => note.id != action.id);
		draft.forwardHistoryNotes = draft.forwardHistoryNotes.filter(note => note.id != action.id);

		draft.backwardHistoryNotes = removeAdjacentDuplicates(draft.backwardHistoryNotes);
		draft.forwardHistoryNotes = removeAdjacentDuplicates(draft.forwardHistoryNotes);

		// Fix the case where after deletion the currently selected note is also the latest in history
		const selectedNoteIds = draft.selectedNoteIds;
		if (selectedNoteIds.length && draft.backwardHistoryNotes.length && draft.backwardHistoryNotes[draft.backwardHistoryNotes.length - 1].id === selectedNoteIds[0]) {
			draft.backwardHistoryNotes = draft.backwardHistoryNotes.slice(0, draft.backwardHistoryNotes.length - 1);
		}
		if (selectedNoteIds.length && draft.forwardHistoryNotes.length && draft.forwardHistoryNotes[draft.forwardHistoryNotes.length - 1].id === selectedNoteIds[0]) {
			draft.forwardHistoryNotes = draft.forwardHistoryNotes.slice(0, draft.forwardHistoryNotes.length - 1);
		}
		break;
	}
	}
}


const reducer = produce((draft: Draft<State> = defaultState, action:any) => {

	// const reducer = (state:State = defaultState, action:any) => {
	// if (!['SIDE_MENU_OPEN_PERCENT'].includes(action.type)) console.info('Action', action.type, action);

	// let newState = state;

	// NOTE_DELETE requires post processing
	if (action.type !== 'NOTE_DELETE') {
		handleHistory(draft, action);
	}

	try {
		switch (action.type) {

		case 'NOTE_SELECT':
		case 'NOTE_SELECT_ADD':
		case 'NOTE_SELECT_REMOVE':
		case 'NOTE_SELECT_TOGGLE':
			changeSelectedNotes(draft, action);
			break;
		case 'NOTE_SELECT_EXTEND':
			{
				if (!draft.selectedNoteIds.length) {
					draft.selectedNoteIds = [action.id];
				} else {
					const selectRangeId1 = draft.selectedNoteIds[draft.selectedNoteIds.length - 1];
					const selectRangeId2 = action.id;
					if (selectRangeId1 === selectRangeId2) {
						// Nothing
					} else {
						const newSelectedNoteIds = draft.selectedNoteIds.slice();
						let selectionStarted = false;
						for (let i = 0; i < draft.notes.length; i++) {
							const id = draft.notes[i].id;

							if (!selectionStarted && (id === selectRangeId1 || id === selectRangeId2)) {
								selectionStarted = true;
								if (newSelectedNoteIds.indexOf(id) < 0) newSelectedNoteIds.push(id);
								continue;
							} else if (selectionStarted && (id === selectRangeId1 || id === selectRangeId2)) {
								if (newSelectedNoteIds.indexOf(id) < 0) newSelectedNoteIds.push(id);
								break;
							}

							if (selectionStarted && newSelectedNoteIds.indexOf(id) < 0) {
								newSelectedNoteIds.push(id);
							}
						}
						draft.selectedNoteIds = newSelectedNoteIds;
					}
				}
			}
			break;

		case 'NOTE_SELECT_ALL':
			draft.selectedNoteIds = draft.notes.map((n:any) => n.id);
			break;

		case 'NOTE_SELECT_ALL_TOGGLE': {
			const allSelected = draft.notes.every((n:any) => draft.selectedNoteIds.includes(n.id));
			if (allSelected) {
				draft.selectedNoteIds = [];
			} else {
				draft.selectedNoteIds = draft.notes.map(n => n.id);
			}
			break;
		}

		case 'SMART_FILTER_SELECT':
			draft.notesParentType = 'SmartFilter';
			draft.selectedSmartFilterId = action.id;
			break;

		case 'FOLDER_SELECT':
			changeSelectedFolder(draft, action, { clearSelectedNoteIds: true });
			break;

		case 'FOLDER_AND_NOTE_SELECT':
			{
				changeSelectedFolder(draft, action);
				const noteSelectAction = Object.assign({}, action, { type: 'NOTE_SELECT' });
				changeSelectedNotes(draft, noteSelectAction);
			}
			break;

		case 'SETTING_UPDATE_ALL':
			draft.settings = action.settings;
			break;

		case 'SETTING_UPDATE_ONE':
			{
				const newSettings = Object.assign({}, draft.settings);
				newSettings[action.key] = action.value;
				draft.settings = newSettings;
			}
			break;

		case 'NOTE_PROVISIONAL_FLAG_CLEAR':
			{
				const newIds = ArrayUtils.removeElement(draft.provisionalNoteIds, action.id);
				if (newIds !== draft.provisionalNoteIds) {
					draft.provisionalNoteIds = newIds;
				}
			}
			break;

			// Replace all the notes with the provided array
		case 'NOTE_UPDATE_ALL':
			draft.notes = action.notes;
			draft.notesSource = action.notesSource;
			updateSelectedNotesFromExistingNotes(draft);
			break;

			// Insert the note into the note list if it's new, or
			// update it within the note array if it already exists.
		case 'NOTE_UPDATE_ONE':
			{
				const modNote = action.note;
				const isViewingAllNotes = (draft.notesParentType === 'SmartFilter' && draft.selectedSmartFilterId === ALL_NOTES_FILTER_ID);
				const isViewingConflictFolder = draft.notesParentType === 'Folder' && draft.selectedFolderId === Folder.conflictFolderId();

				const noteIsInFolder = function(note:any, folderId:string) {
					if (note.is_conflict && isViewingConflictFolder) return true;
					if (!('parent_id' in modNote) || note.parent_id == folderId) return true;
					return false;
				};

				let movedNotePreviousIndex = 0;
				let noteFolderHasChanged = false;
				let newNotes = draft.notes.slice();
				let found = false;
				for (let i = 0; i < newNotes.length; i++) {
					const n = newNotes[i];
					if (n.id == modNote.id) {
						// Note is still in the same folder
						if (isViewingAllNotes || noteIsInFolder(modNote, n.parent_id)) {
							// Merge the properties that have changed (in modNote) into
							// the object we already have.
							newNotes[i] = Object.assign({}, newNotes[i]);

							for (const n in modNote) {
								if (!modNote.hasOwnProperty(n)) continue;
								newNotes[i][n] = modNote[n];
							}
						} else {
							// Note has moved to a different folder
							newNotes.splice(i, 1);
							noteFolderHasChanged = true;
							movedNotePreviousIndex = i;
						}
						found = true;
						break;
					}
				}

				// Note was not found - if the current folder is the same as the note folder,
				// add it to it.
				if (!found) {
					if (isViewingAllNotes || noteIsInFolder(modNote, draft.selectedFolderId)) {
						newNotes.push(modNote);
					}
				}

				// newNotes = Note.sortNotes(newNotes, draft.notesOrder, draft.settings.uncompletedTodosOnTop);
				newNotes = Note.sortNotes(newNotes, stateUtils.notesOrder(draft.settings), draft.settings.uncompletedTodosOnTop);
				draft.notes = newNotes;

				if (noteFolderHasChanged) {
					let newIndex = movedNotePreviousIndex;
					if (newIndex >= newNotes.length) newIndex = newNotes.length - 1;
					if (!newNotes.length) newIndex = -1;
					draft.selectedNoteIds = newIndex >= 0 ? [newNotes[newIndex].id] : [];
				}

				let newProvisionalNoteIds = draft.provisionalNoteIds;

				if (action.provisional) {
					newProvisionalNoteIds = newProvisionalNoteIds.slice();
					newProvisionalNoteIds.push(modNote.id);
				} else {
					const idx = newProvisionalNoteIds.indexOf(modNote.id);
					if (idx >= 0) {
						newProvisionalNoteIds = newProvisionalNoteIds.slice();
						newProvisionalNoteIds.splice(idx, 1);

					}
				}

				draft.provisionalNoteIds = newProvisionalNoteIds;
			}
			break;

		case 'NOTE_DELETE':

			{
				handleItemDelete(draft, action);

				const idx = draft.provisionalNoteIds.indexOf(action.id);
				if (idx >= 0) {
					const t = draft.provisionalNoteIds.slice();
					t.splice(idx, 1);
					draft.provisionalNoteIds = t;
				}
			}
			break;

		case 'NOTE_IS_INSERTING_NOTES':

			if (draft.isInsertingNotes !== action.value) {
				draft.isInsertingNotes = action.value;
			}
			break;

		case 'TAG_DELETE':
			handleItemDelete(draft, action);
			draft.selectedNoteTags = removeItemFromArray(draft.selectedNoteTags, 'id', action.id);
			break;

		case 'FOLDER_UPDATE_ALL':
			draft.folders = action.items;
			break;

		case 'FOLDER_SET_COLLAPSED':
			folderSetCollapsed(draft, action);
			break;

		case 'FOLDER_TOGGLE':
			if (draft.collapsedFolderIds.indexOf(action.id) >= 0) {
				folderSetCollapsed(draft, Object.assign({ collapsed: false }, action));
			} else {
				folderSetCollapsed(draft, Object.assign({ collapsed: true }, action));
			}
			break;

		case 'FOLDER_SET_COLLAPSED_ALL':
			draft.collapsedFolderIds = action.ids.slice();
			break;

		case 'TAG_UPDATE_ALL':
			draft.tags = action.items;
			break;

		case 'TAG_SELECT':

			if (draft.selectedTagId !== action.id) {
				draft.selectedTagId = action.id;
				if (!action.id) {
					draft.notesParentType = defaultNotesParentType(draft, 'Tag');
				} else {
					draft.notesParentType = 'Tag';
				}
				draft.selectedNoteIds = [];
			}
			break;

		case 'TAG_UPDATE_ONE':
			{
				// We only want to update the selected note tags if the tag belongs to the currently open note
				const selectedNoteHasTag = !!draft.selectedNoteTags.find(tag => tag.id === action.item.id);
				updateOneItem(draft, action);
				if (selectedNoteHasTag) updateOneItem(draft, action, 'selectedNoteTags');
			}
			break;

		case 'NOTE_TAG_REMOVE':
			{
				updateOneItem(draft, action, 'tags');
				const tagRemoved = action.item;
				draft.selectedNoteTags = removeItemFromArray(draft.selectedNoteTags, 'id', tagRemoved.id);
			}
			break;

		case 'EDITOR_NOTE_STATUS_SET':

			{
				draft.editorNoteStatuses[action.id] = action.status;
			}
			break;

		case 'EDITOR_NOTE_STATUS_REMOVE':

			{
				delete draft.editorNoteStatuses[action.id];
			}
			break;

		case 'FOLDER_UPDATE_ONE':
		case 'MASTERKEY_UPDATE_ONE':
			updateOneItem(draft, action);
			break;

		case 'FOLDER_DELETE':
			handleItemDelete(draft, action);
			break;

		case 'MASTERKEY_UPDATE_ALL':
			draft.masterKeys = action.items;
			break;

		case 'MASTERKEY_SET_NOT_LOADED':
			draft.notLoadedMasterKeys = action.ids;
			break;

		case 'MASTERKEY_ADD_NOT_LOADED':
			{
				if (draft.notLoadedMasterKeys.indexOf(action.id) < 0) {
					const keys = draft.notLoadedMasterKeys.slice();
					keys.push(action.id);
					draft.notLoadedMasterKeys = keys;
				}
			}
			break;

		case 'MASTERKEY_REMOVE_NOT_LOADED':
			{
				const ids = action.id ? [action.id] : action.ids;
				for (let i = 0; i < ids.length; i++) {
					const id = ids[i];
					const index = draft.notLoadedMasterKeys.indexOf(id);
					if (index >= 0) {
						const keys = draft.notLoadedMasterKeys.slice();
						keys.splice(index, 1);
						draft.notLoadedMasterKeys = keys;
					}
				}
			}
			break;

		case 'SYNC_STARTED':
			draft.syncStarted = true;
			break;

		case 'SYNC_COMPLETED':
			draft.syncStarted = false;
			break;

		case 'SYNC_REPORT_UPDATE':
			draft.syncReport = action.report;
			break;

		case 'SEARCH_QUERY':
			draft.searchQuery = action.query.trim();
			break;

		case 'SEARCH_ADD':
			{
				const searches = draft.searches.slice();
				searches.push(action.search);
				draft.searches = searches;
			}
			break;

		case 'SEARCH_UPDATE':
			{
				const searches = draft.searches.slice();
				let found = false;
				for (let i = 0; i < searches.length; i++) {
					if (searches[i].id === action.search.id) {
						searches[i] = Object.assign({}, action.search);
						found = true;
						break;
					}
				}

				if (!found) searches.push(action.search);

				if (!action.search.query_pattern) {
					draft.notesParentType = defaultNotesParentType(draft, 'Search');
				} else {
					draft.notesParentType = 'Search';
				}

				draft.searches = searches;
			}
			break;

		case 'SEARCH_DELETE':
			handleItemDelete(draft, action);
			break;

		case 'SEARCH_SELECT':
			draft.selectedSearchId = action.id;
			if (!action.id) {
				draft.notesParentType = defaultNotesParentType(draft, 'Search');
			} else {
				draft.notesParentType = 'Search';
			}
			draft.selectedNoteIds = [];
			break;
		case 'SET_HIGHLIGHTED':
			draft.highlightedWords = action.words;
			break;

		case 'APP_STATE_SET':
			draft.appState = action.state;
			break;

		case 'SYNC_HAS_DISABLED_SYNC_ITEMS':
			draft.hasDisabledSyncItems = true;
			break;

		case 'ENCRYPTION_HAS_DISABLED_ITEMS':
			draft.hasDisabledEncryptionItems = action.value;
			break;

		case 'CLIPPER_SERVER_SET':
			{
				const clipperServer = Object.assign({}, draft.clipperServer);
				if ('startState' in action) clipperServer.startState = action.startState;
				if ('port' in action) clipperServer.port = action.port;
				draft.clipperServer = clipperServer;
			}
			break;

		case 'DECRYPTION_WORKER_SET':
			{
				const decryptionWorker = Object.assign({}, draft.decryptionWorker);
				for (const n in action) {
					if (!action.hasOwnProperty(n) || n === 'type') continue;
					(decryptionWorker as any)[n] = action[n];
				}
				draft.decryptionWorker = decryptionWorker;
			}
			break;

		case 'RESOURCE_FETCHER_SET':
			{
				const rf = Object.assign({}, action);
				delete rf.type;
				draft.resourceFetcher = rf;
			}
			break;

		case 'LOAD_CUSTOM_CSS':
			draft.customCss = action.css;
			break;

		case 'TEMPLATE_UPDATE_ALL':
			draft.templates = action.templates;
			break;

		case 'SET_NOTE_TAGS':
			draft.selectedNoteTags = action.items;
			break;

		case 'PLUGINLEGACY_DIALOG_SET':
			{
				if (!action.pluginName) throw new Error('action.pluginName not specified');
				const newPluginsLegacy = Object.assign({}, draft.pluginsLegacy);
				const newPlugin = draft.pluginsLegacy[action.pluginName] ? Object.assign({}, draft.pluginsLegacy[action.pluginName]) : {};
				if ('open' in action) newPlugin.dialogOpen = action.open;
				if ('userData' in action) newPlugin.userData = action.userData;
				newPluginsLegacy[action.pluginName] = newPlugin;
				draft.pluginsLegacy = newPluginsLegacy;
			}
			break;
		}
	} catch (error) {
		error.message = `In reducer: ${error.message} Action: ${JSON.stringify(action)}`;
		throw error;
	}

	if (action.type.indexOf('NOTE_UPDATE') === 0 || action.type.indexOf('FOLDER_UPDATE') === 0 || action.type.indexOf('TAG_UPDATE') === 0) {
		draft.hasEncryptedItems = stateHasEncryptedItems(draft);
	}

	if (action.type === 'NOTE_DELETE') {
		handleHistory(draft, action);
	}

	for (const additionalReducer of additionalReducers) {
		additionalReducer.reducer(draft, action);
	}

	// if (Setting.value('env') === 'dev') {
	// 	return Object.freeze(newState);
	// } else {
	// 	return newState;
	// }
});

export default reducer;