import { ModelInstanceCreator } from './datastore/datastore';
import { exhaustiveCheck } from './util';

//#region Schema types
export type Schema = UserSchema & {
	version: string;
};
export type UserSchema = {
	models: SchemaModels;
	nonModels?: SchemaNonModels;
	relationships?: RelationshipType;
	enums: SchemaEnums;
	modelTopologicalOrdering?: Map<string, string[]>;
};
export type InternalSchema = {
	namespaces: SchemaNamespaces;
	version: string;
};
export type SchemaNamespaces = Record<string, SchemaNamespace>;
export type SchemaNamespace = UserSchema & {
	name: string;
};
export type SchemaModels = Record<string, SchemaModel>;
export type SchemaModel = {
	name: string;
	pluralName: string;
	attributes?: ModelAttributes;
	fields: ModelFields;
	syncable?: boolean;
};
export function isSchemaModel(obj: any): obj is SchemaModel {
	return obj && (<SchemaModel>obj).pluralName !== undefined;
}
export type SchemaNonModels = Record<string, SchemaNonModel>;
export type SchemaNonModel = {
	name: string;
	fields: ModelFields;
};
type SchemaEnums = Record<string, SchemaEnum>;
type SchemaEnum = {
	name: string;
	values: string[];
};

export type ModelAssociation = AssociatedWith | TargetNameAssociation;
type AssociatedWith = {
	connectionType: 'HAS_MANY' | 'HAS_ONE';
	associatedWith: string;
};
export function isAssociatedWith(obj: any): obj is AssociatedWith {
	return obj && obj.associatedWith;
}

type TargetNameAssociation = {
	connectionType: 'BELONGS_TO';
	targetName: string;
};
export function isTargetNameAssociation(
	obj: any
): obj is TargetNameAssociation {
	return obj && obj.targetName;
}

type ModelAttributes = ModelAttribute[];
type ModelAttribute = { type: string; properties?: Record<string, any> };

export type ModelFields = Record<string, ModelField>;
export enum GraphQLScalarType {
	ID,
	String,
	Int,
	Float,
	Boolean,
	AWSDate,
	AWSTime,
	AWSDateTime,
	AWSTimestamp,
	AWSEmail,
	AWSJSON,
	AWSURL,
	AWSPhone,
	AWSIPAddress,
}

export namespace GraphQLScalarType {
	export function getJSType(
		scalar: keyof Omit<typeof GraphQLScalarType, 'getJSType'>
	): 'string' | 'number' | 'boolean' {
		switch (scalar) {
			case 'Boolean':
				return 'boolean';
			case 'ID':
			case 'String':
			case 'AWSDate':
			case 'AWSTime':
			case 'AWSDateTime':
			case 'AWSEmail':
			case 'AWSJSON':
			case 'AWSURL':
			case 'AWSPhone':
			case 'AWSIPAddress':
				return 'string';
			case 'Int':
			case 'Float':
			case 'AWSTimestamp':
				return 'number';
			default:
				exhaustiveCheck(scalar);
		}
	}
}

export type AuthorizationRule = {
	identityClaim: string;
	ownerField: string;
	provider: 'userPools' | 'oidc' | 'iam' | 'apiKey';
	groupClaim: string;
	groups: [string];
	authStrategy: 'owner' | 'groups' | 'private' | 'public';
	areSubscriptionsPublic: boolean;
};

export function isGraphQLScalarType(
	obj: any
): obj is keyof Omit<typeof GraphQLScalarType, 'getJSType'> {
	return obj && GraphQLScalarType[obj] !== undefined;
}

export type ModelFieldType = { model: string };
export function isModelFieldType(obj: any): obj is ModelFieldType {
	const modelField: keyof ModelFieldType = 'model';
	if (obj && obj[modelField]) return true;

	return false;
}

export type NonModelFieldType = { nonModel: string };
export function isNonModelFieldType(obj: any): obj is NonModelFieldType {
	const typeField: keyof NonModelFieldType = 'nonModel';
	if (obj && obj[typeField]) return true;

	return false;
}

type EnumFieldType = { enum: string };
export function isEnumFieldType(obj: any): obj is EnumFieldType {
	const modelField: keyof EnumFieldType = 'enum';
	if (obj && obj[modelField]) return true;

	return false;
}

type ModelField = {
	name: string;
	type:
		| keyof Omit<typeof GraphQLScalarType, 'getJSType'>
		| ModelFieldType
		| NonModelFieldType
		| EnumFieldType;
	isArray: boolean;
	isRequired?: boolean;
	association?: ModelAssociation;
	attributes?: ModelAttributes[];
};
//#endregion

//#region Model definition
export type NonModelTypeConstructor<T> = {
	new (init: T): T;
};
export type PersistentModelConstructor<T extends PersistentModel> = {
	new (init: ModelInit<T>): T;
	copyOf(src: T, mutator: (draft: MutableModel<T>) => void): T;
};
export type TypeConstructorMap = Record<
	string,
	PersistentModelConstructor<any> | NonModelTypeConstructor<any>
>;
export type PersistentModel = Readonly<{ id: string } & Record<string, any>>;
export type ModelInit<T> = Omit<T, 'id'>;
type DeepWritable<T> = {
	-readonly [P in keyof T]: T[P] extends TypeName<T[P]>
		? T[P]
		: DeepWritable<T[P]>;
};
export type MutableModel<T> = Omit<DeepWritable<T>, 'id'>;

export type ModelInstanceMetadata = {
	id: string;
	_version: number;
	_lastChangedAt: number;
	_deleted: boolean;
};

//#endregion

//#region Subscription messages
export enum OpType {
	INSERT = 'INSERT',
	UPDATE = 'UPDATE',
	DELETE = 'DELETE',
}

export type SubscriptionMessage<T extends PersistentModel> = {
	opType: OpType;
	element: T;
	model: PersistentModelConstructor<T>;
	condition: PredicatesGroup<T> | null;
};
//#endregion

//#region Predicates
export type PredicateExpression<M extends PersistentModel, FT> = TypeName<
	FT
> extends keyof MapTypeToOperands<FT>
	? (
			operator: keyof MapTypeToOperands<FT>[TypeName<FT>],
			operand: MapTypeToOperands<FT>[TypeName<FT>][keyof MapTypeToOperands<
				FT
			>[TypeName<FT>]]
	  ) => ModelPredicate<M>
	: never;

type EqualityOperators<T> = {
	ne: T;
	eq: T;
};
type ScalarNumberOperators<T> = EqualityOperators<T> & {
	le: T;
	lt: T;
	ge: T;
	gt: T;
};
type NumberOperators<T> = ScalarNumberOperators<T> & {
	between: [T, T];
};
type StringOperators<T> = ScalarNumberOperators<T> & {
	beginsWith: T;
	contains: T;
	notContains: T;
};
type BooleanOperators<T> = EqualityOperators<T>;
type ArrayOperators<T> = {
	contains: T;
	notContains: T;
};
export type AllOperators = NumberOperators<any> &
	StringOperators<any> &
	ArrayOperators<any>;

type MapTypeToOperands<T> = {
	number: NumberOperators<NonNullable<T>>;
	string: StringOperators<NonNullable<T>>;
	boolean: BooleanOperators<NonNullable<T>>;
	'number[]': ArrayOperators<number>;
	'string[]': ArrayOperators<string>;
	'boolean[]': ArrayOperators<boolean>;
};

type TypeName<T> = T extends string
	? 'string'
	: T extends number
	? 'number'
	: T extends boolean
	? 'boolean'
	: T extends string[]
	? 'string[]'
	: T extends number[]
	? 'number[]'
	: T extends boolean[]
	? 'boolean[]'
	: never;

export type PredicateGroups<T extends PersistentModel> = {
	and: (
		predicate: (predicate: ModelPredicate<T>) => ModelPredicate<T>
	) => ModelPredicate<T>;
	or: (
		predicate: (predicate: ModelPredicate<T>) => ModelPredicate<T>
	) => ModelPredicate<T>;
	not: (
		predicate: (predicate: ModelPredicate<T>) => ModelPredicate<T>
	) => ModelPredicate<T>;
};

export type ModelPredicate<M extends PersistentModel> = {
	[K in keyof M]-?: PredicateExpression<M, NonNullable<M[K]>>;
} &
	PredicateGroups<M>;

export type ProducerModelPredicate<M extends PersistentModel> = (
	condition: ModelPredicate<M>
) => ModelPredicate<M>;

export type PredicatesGroup<T extends PersistentModel> = {
	type: keyof PredicateGroups<T>;
	predicates: (PredicateObject<T> | PredicatesGroup<T>)[];
};

export function isPredicateObj<T extends PersistentModel>(
	obj: any
): obj is PredicateObject<T> {
	return obj && (<PredicateObject<T>>obj).field !== undefined;
}

export function isPredicateGroup<T extends PersistentModel>(
	obj: any
): obj is PredicatesGroup<T> {
	return obj && (<PredicatesGroup<T>>obj).type !== undefined;
}

export type PredicateObject<T extends PersistentModel> = {
	field: keyof T;
	operator: keyof AllOperators;
	operand: any;
};

export enum QueryOne {
	FIRST,
	LAST,
}

export type GraphQLCondition = Partial<
	| {
			[field: string]: {
				[operator: string]: string | number | [number, number];
			};
	  }
	| {
			and: [GraphQLCondition];
			or: [GraphQLCondition];
			not: GraphQLCondition;
	  }
>;

//#endregion

//#region Pagination

export type PaginationInput = {
	limit?: number;
	page?: number;
};

//#endregion

//#region System Components

export type SystemComponent = {
	setUp(
		schema: InternalSchema,
		namespaceResolver: NamespaceResolver,
		modelInstanceCreator: ModelInstanceCreator,
		getModelConstructorByModelName: (
			namsespaceName: string,
			modelName: string
		) => PersistentModelConstructor<any>
	): Promise<void>;
};

export type NamespaceResolver = (
	modelConstructor: PersistentModelConstructor<any>
) => string;

export type ControlMessageType<T> = {
	type: T;
	data?: any;
};

//#endregion

//#region Relationship types
export type RelationType = {
	fieldName: string;
	modelName: string;
	relationType: 'HAS_ONE' | 'HAS_MANY' | 'BELONGS_TO';
	targetName?: string;
	associatedWith?: string;
};

export type RelationshipType = {
	[modelName: string]: { indexes: string[]; relationTypes: RelationType[] };
};

//#endregion

//#region DataStore config types
export type DataStoreConfig = {
	DataStore?: {
		conflictHandler?: ConflictHandler; // default : retry until client wins up to x times
		errorHandler?: (error: SyncError) => void; // default : logger.warn
		maxRecordsToSync?: number; // merge
		syncPageSize?: number;
		fullSyncInterval?: number;
	};
	conflictHandler?: ConflictHandler; // default : retry until client wins up to x times
	errorHandler?: (error: SyncError) => void; // default : logger.warn
	maxRecordsToSync?: number; // merge
	syncPageSize?: number;
	fullSyncInterval?: number;
};

export type SyncConflict = {
	modelConstructor: PersistentModelConstructor<any>;
	localModel: PersistentModel;
	remoteModel: PersistentModel;
	operation: OpType;
	attempts: number;
};

export type SyncError = {
	message: string;
	errorType: string;
	errorInfo: string;
	localModel: PersistentModel;
	remoteModel: PersistentModel;
	operation: string;
};

export const DISCARD = Symbol('DISCARD');

export type ConflictHandler = (
	conflict: SyncConflict
) =>
	| Promise<PersistentModel | typeof DISCARD>
	| PersistentModel
	| typeof DISCARD;
export type ErrorHandler = (error: SyncError) => void;
//#endregion