import type { IAddressSpace, UADataType } from "node-opcua-address-space-base";
import { checkDebugFlag, make_debugLog, make_errorLog } from "node-opcua-debug";
import type { ExtensionObject } from "node-opcua-extension-object";
import type { NodeId } from "node-opcua-nodeid";
import { NodeClass } from "node-opcua-types";
import { Xml2Json } from "node-opcua-xml2json";

import { type DefinitionMap2, makeXmlExtensionObjectReader, type TypeInfo } from "./make_xml_extension_object_parser";

const doDebug = checkDebugFlag(__filename);
const debugLog = make_debugLog(__filename);
const _errorLog = make_errorLog(__filename);

function encodingNodeIdToDataTypeNode(addressSpace: IAddressSpace, encodingNodeId: NodeId): UADataType {
    const encodingNode = addressSpace.findNode(encodingNodeId)!;

    // c8 ignore next
    if (!encodingNode) {
        throw new Error(`findDataTypeNode:  Cannot find encoding NodeId${encodingNodeId.toString()}`);
    }
    const refs = encodingNode.findReferences("HasEncoding", false);
    const dataTypes = refs.map((ref) => addressSpace.findNode(ref.nodeId)).filter((obj: any) => obj !== null);
    // c8 ignore next
    if (dataTypes.length !== 1) {
        throw new Error("Internal Error");
    }
    const dataTypeNode = dataTypes[0] as UADataType;
    return dataTypeNode;
}

export function makeDefinitionMap(addressSpace: IAddressSpace): DefinitionMap2 {
    return {
        findDefinition(dataTypeNodeId: NodeId): TypeInfo {
            const dataTypeNode = addressSpace.findDataType(dataTypeNodeId);
            if (!dataTypeNode) {
                throw new Error(`findDefinition: cannot find dataType ${dataTypeNodeId.toString()}`);
            }
            if (dataTypeNode.nodeClass !== NodeClass.DataType) {
                throw new Error("Expecting a DataType node here");
            }
            const name = dataTypeNode.browseName.name || "";
            if (dataTypeNode.isStructure()) {
                const definition = dataTypeNode.getStructureDefinition();
                return { name, definition };
            } else if (dataTypeNode.isEnumeration()) {
                const definition = dataTypeNode.getEnumDefinition();
                return { name, definition };
            } else {
                const dataType = dataTypeNode.getBasicDataType();
                return { name, definition: { dataType } };
            }
        }
    };
}
export function decodeXmlExtensionObject(
    addressSpace: IAddressSpace,
    encodingNodeId: NodeId,
    xmlBody: string,
    translateNodeId: (nodeId: string) => NodeId
): ExtensionObject | null {
    const definitionMap = makeDefinitionMap(addressSpace);

    const dataType = encodingNodeIdToDataTypeNode(addressSpace, encodingNodeId)!;

    //  const { name, definition } = definitionMap.findDefinition(dataType.nodeId);
    // const hasOptionalFields = definition.fields!.some((field) => field.isOptional);

    const reader = makeXmlExtensionObjectReader(dataType.nodeId, definitionMap, new Map(), translateNodeId);
    const parser2 = new Xml2Json(reader);
    const pojo = parser2.parseString(xmlBody);

    const userDefinedExtensionObject = addressSpace.constructExtensionObject(dataType, pojo);

    // c8 ignore next
    if (doDebug) {
        debugLog("userDefinedExtensionObject", userDefinedExtensionObject.toString());
    }
    //
    return userDefinedExtensionObject;
}