import {
    filePathToPseudoNamespace,
    snakeToCamel,
    uppercaseFirst,
    oneOfName,
    isProto2,
    withinNamespaceFromExportEntry,
    normaliseFieldObjectName,
    stripPrefix,
} from '../util';
import { ExportMap } from '../ExportMap';
import {
    FieldDescriptorProto,
    FileDescriptorProto,
    DescriptorProto,
    FieldOptions,
} from 'google-protobuf/google/protobuf/descriptor_pb';
import {
    MESSAGE_TYPE,
    BYTES_TYPE,
    ENUM_TYPE,
    getFieldType,
    getTypeName,
} from './FieldTypes';
import { Printer } from '../Printer';
import { printEnum } from './enum';
import { printOneOfDecl } from './oneof';
import { printExtension } from './extensions';
import JSType = FieldOptions.JSType;

function hasFieldPresence(
    field: FieldDescriptorProto,
    fileDescriptor: FileDescriptorProto
): boolean {
    if (field.getLabel() === FieldDescriptorProto.Label.LABEL_REPEATED) {
        return false;
    }

    if (field.hasOneofIndex()) {
        return true;
    }

    if (field.getType() === MESSAGE_TYPE) {
        return true;
    }

    if (isProto2(fileDescriptor)) {
        return true;
    }

    return false;
}

export function printMessage(
    fileName: string,
    exportMap: ExportMap,
    messageDescriptor: DescriptorProto,
    indentLevel: number,
    fileDescriptor: FileDescriptorProto
) {
    const messageName = messageDescriptor.getName();
    const messageOptions = messageDescriptor.getOptions();
    if (messageOptions !== undefined && messageOptions.getMapEntry()) {
        // this message type is the entry tuple for a map - don't output it
        return '';
    }

    const objectTypeName = `AsObject`;
    const toObjectType = new Printer(indentLevel + 1);
    toObjectType.printLn(`export type ${objectTypeName} = {`);

    const printer = new Printer(indentLevel);
    printer.printEmptyLn();
    printer.printLn(`export class ${messageName} extends jspb.Message {`);

    const oneOfGroups: Array<Array<FieldDescriptorProto>> = [];

    messageDescriptor.getFieldList().forEach((field) => {
        if (field.hasOneofIndex()) {
            const oneOfIndex = field.getOneofIndex() as number;
            let existing = oneOfGroups[oneOfIndex];
            if (existing === undefined) {
                existing = [];
                oneOfGroups[oneOfIndex] = existing;
            }
            existing.push(field);
        }
        const snakeCaseName = stripPrefix((field.getName() as string).toLowerCase(), '_');
        const camelCaseName = snakeToCamel(snakeCaseName);
        const withUppercase = uppercaseFirst(camelCaseName);
        const type = field.getType();

        let exportType;
        const fullTypeName = (field.getTypeName() as string).slice(1);
        if (type === MESSAGE_TYPE) {
            const fieldMessageType = exportMap.getMessage(fullTypeName);
            if (fieldMessageType === undefined) {
                throw new Error('No message export for: ' + fullTypeName);
            }
            if (
                fieldMessageType.messageOptions !== undefined &&
                fieldMessageType.messageOptions.getMapEntry()
            ) {
                // This field is a map
                const keyTuple = fieldMessageType.mapFieldOptions!.key;
                const keyType = keyTuple[0];
                const keyTypeName = getFieldType(
                    keyType,
                    keyTuple[1],
                    fileName,
                    exportMap
                );
                const valueTuple = fieldMessageType.mapFieldOptions!.value;
                const valueType = valueTuple[0];
                let valueTypeName = getFieldType(
                    valueType,
                    valueTuple[1],
                    fileName,
                    exportMap
                );
                if (valueType === BYTES_TYPE) {
                    valueTypeName = 'Uint8Array | string';
                }
                if (valueType === ENUM_TYPE) {
                    valueTypeName = `${valueTypeName}[keyof ${valueTypeName}]`;
                }
                printer.printIndentedLn(
                    `get${withUppercase}Map(): jspb.Map<${keyTypeName}, ${valueTypeName}>;`
                );
                printer.printIndentedLn(`clear${withUppercase}Map(): void;`);
                toObjectType.printIndentedLn(
                    `${camelCaseName}Map: Array<[${keyTypeName}${
                        keyType === MESSAGE_TYPE ? '.AsObject' : ''
                    }, ${valueTypeName}${
                        valueType === MESSAGE_TYPE ? '.AsObject' : ''
                    }]>,`
                );
                return;
            }
            const withinNamespace = withinNamespaceFromExportEntry(
                fullTypeName,
                fieldMessageType
            );
            if (fieldMessageType.fileName === fileName) {
                exportType = withinNamespace;
            } else {
                exportType =
                    filePathToPseudoNamespace(fieldMessageType.fileName) +
                    '.' +
                    withinNamespace;
            }
        } else if (type === ENUM_TYPE) {
            const fieldEnumType = exportMap.getEnum(fullTypeName);
            if (fieldEnumType === undefined) {
                throw new Error('No enum export for: ' + fullTypeName);
            }
            const withinNamespace = withinNamespaceFromExportEntry(
                fullTypeName,
                fieldEnumType
            );
            if (fieldEnumType.fileName === fileName) {
                exportType = withinNamespace;
            } else {
                exportType =
                    filePathToPseudoNamespace(fieldEnumType.fileName) +
                    '.' +
                    withinNamespace;
            }
            exportType = `${exportType}Map[keyof ${exportType}Map]`;
        } else {
            const options = field.getOptions() as FieldOptions;
            if (options && options.hasJstype()) {
                switch (options.getJstype()) {
                    case JSType.JS_NUMBER:
                        exportType = 'number';
                        break;
                    case JSType.JS_STRING:
                        exportType = 'string';
                        break;
                    default:
                        exportType = getTypeName((type as unknown) as number);
                }
            } else {
                exportType = getTypeName((type as unknown) as number);
            }
        }

        let hasClearMethod = false;
        function printClearIfNotPresent() {
            if (!hasClearMethod) {
                hasClearMethod = true;
                printer.printIndentedLn(
                    `clear${withUppercase}${
                        field.getLabel() === FieldDescriptorProto.Label.LABEL_REPEATED
                            ? 'List'
                            : ''
                    }(): void;`
                );
            }
        }

        if (hasFieldPresence(field, fileDescriptor)) {
            printer.printIndentedLn(`has${withUppercase}(): boolean;`);
            printClearIfNotPresent();
        }

        function printRepeatedAddMethod(valueType: string) {
            const optionalValue = field.getType() === MESSAGE_TYPE;
            printer.printIndentedLn(
                `add${withUppercase}(value${
                    optionalValue ? '?' : ''
                }: ${valueType}, index?: number): ${valueType};`
            );
        }

        if (field.getLabel() === FieldDescriptorProto.Label.LABEL_REPEATED) {
            // is repeated
            printClearIfNotPresent();
            if (type === BYTES_TYPE) {
                toObjectType.printIndentedLn(
                    `${camelCaseName}List: Array<Uint8Array | string>,`
                );
                printer.printIndentedLn(
                    `get${withUppercase}List(): Array<Uint8Array | string>;`
                );
                printer.printIndentedLn(
                    `get${withUppercase}List_asU8(): Array<Uint8Array>;`
                );
                printer.printIndentedLn(
                    `get${withUppercase}List_asB64(): Array<string>;`
                );
                printer.printIndentedLn(
                    `set${withUppercase}List(value: Array<Uint8Array | string>): void;`
                );
                printRepeatedAddMethod('Uint8Array | string');
            } else {
                toObjectType.printIndentedLn(
                    `${camelCaseName}List: Array<${exportType}${
                        type === MESSAGE_TYPE ? '.AsObject' : ''
                    }>,`
                );
                printer.printIndentedLn(
                    `get${withUppercase}List(): Array<${exportType}>;`
                );
                printer.printIndentedLn(
                    `set${withUppercase}List(value: Array<${exportType}>): void;`
                );
                printRepeatedAddMethod(exportType);
            }
        } else {
            if (type === BYTES_TYPE) {
                toObjectType.printIndentedLn(`${camelCaseName}: Uint8Array | string,`);
                printer.printIndentedLn(`get${withUppercase}(): Uint8Array | string;`);
                printer.printIndentedLn(`get${withUppercase}_asU8(): Uint8Array;`);
                printer.printIndentedLn(`get${withUppercase}_asB64(): string;`);
                printer.printIndentedLn(
                    `set${withUppercase}(value: Uint8Array | string): void;`
                );
            } else {
                let fieldObjectType = exportType;
                let canBeUndefined = false;
                if (type === MESSAGE_TYPE) {
                    fieldObjectType += '.AsObject';
                    if (
                        !isProto2(fileDescriptor) ||
                        field.getLabel() === FieldDescriptorProto.Label.LABEL_OPTIONAL
                    ) {
                        canBeUndefined = true;
                    }
                } else {
                    if (isProto2(fileDescriptor)) {
                        canBeUndefined = true;
                    }
                }
                const fieldObjectName = normaliseFieldObjectName(camelCaseName);
                toObjectType.printIndentedLn(
                    `${fieldObjectName}${canBeUndefined ? '?' : ''}: ${fieldObjectType},`
                );
                printer.printIndentedLn(
                    `get${withUppercase}(): ${exportType}${
                        canBeUndefined ? ' | undefined' : ''
                    };`
                );
                printer.printIndentedLn(
                    `set${withUppercase}(value${
                        type === MESSAGE_TYPE ? '?' : ''
                    }: ${exportType}): void;`
                );
            }
        }
        printer.printEmptyLn();
    });

    toObjectType.printLn(`}`);

    messageDescriptor.getOneofDeclList().forEach((oneOfDecl) => {
        const name = oneOfDecl.getName() as string;
        printer.printIndentedLn(
            `get${oneOfName(name)}Case(): ${messageName}.${oneOfName(name)}Case;`
        );
    });

    printer.printIndentedLn(`serializeBinary(): Uint8Array;`);
    printer.printIndentedLn(
        `toObject(includeInstance?: boolean): ${messageName}.${objectTypeName};`
    );
    printer.printIndentedLn(
        `static toObject(includeInstance: boolean, msg: ${messageName}): ${messageName}.${objectTypeName};`
    );
    printer.printIndentedLn(
        `static extensions: {[key: number]: jspb.ExtensionFieldInfo<jspb.Message>};`
    );
    printer.printIndentedLn(
        `static extensionsBinary: {[key: number]: jspb.ExtensionFieldBinaryInfo<jspb.Message>};`
    );
    printer.printIndentedLn(
        `static serializeBinaryToWriter(message: ${messageName}, writer: jspb.BinaryWriter): void;`
    );
    printer.printIndentedLn(
        `static deserializeBinary(bytes: Uint8Array): ${messageName};`
    );
    printer.printIndentedLn(
        `static deserializeBinaryFromReader(message: ${messageName}, reader: jspb.BinaryReader): ${messageName};`
    );

    printer.printLn(`}`);
    printer.printEmptyLn();

    printer.printLn(`export namespace ${messageName} {`);

    printer.print(toObjectType.getOutput());

    messageDescriptor.getNestedTypeList().forEach((nested) => {
        const msgOutput = printMessage(
            fileName,
            exportMap,
            nested,
            indentLevel + 1,
            fileDescriptor
        );
        if (msgOutput !== '') {
            // If the message class is a Map entry then it isn't output, so don't print the namespace block
            printer.print(msgOutput);
        }
    });
    messageDescriptor.getEnumTypeList().forEach((enumType) => {
        printer.print(`${printEnum(enumType, indentLevel + 1)}`);
    });
    messageDescriptor.getOneofDeclList().forEach((oneOfDecl, index) => {
        printer.print(
            `${printOneOfDecl(oneOfDecl, oneOfGroups[index] || [], indentLevel + 1)}`
        );
    });
    messageDescriptor.getExtensionList().forEach((extension) => {
        printer.print(printExtension(fileName, exportMap, extension, indentLevel + 1));
    });

    printer.printLn(`}`);

    return printer.getOutput();
}