import { createUserReturn, User, Process } from '../dist/pkg/sdk_client';
import IndexedDB from './database'
import { WebSocketClient } from './websockets';

class Services {
    private static instance: Services;
    private sdkClient: any;
    private current_process: string | null = null;
    private websocketConnection: WebSocketClient[] = [];

    // Private constructor to prevent direct instantiation from outside
    private constructor() {}

    // Method to access the singleton instance of Services
    public static async getInstance(): Promise<Services> {
        if (!Services.instance) {
            Services.instance = new Services();
            await Services.instance.init(); 
        }
        return Services.instance;
    }

    // The init method is now part of the instance, and should only be called once
    private async init(): Promise<void> {
        this.sdkClient = await import("../dist/pkg/sdk_client");
        this.sdkClient.setup();
    }

    // public async getSpAddressDefaultClient(): Promise<string | null> {
    //     try {
    //         const indexedDB = await IndexedDB.getInstance();
    //         const db = indexedDB.getDb();
    //         const spClient = await indexedDB.getObject<string>(db, indexedDB.getStoreList().SpClient, "default");

    //         if (spClient) {
    //             return this.sdkClient.get_receiving_address(spClient);
    //         } else {
    //             console.error("SP client not found");
    //             return null;
    //         }
    //     } catch (error) {
    //         console.error("Failed to retrieve object or get sp address:", error);
    //         return null; 
    //     }

    // }

    public async addWebsocketConnection(url: string): Promise<void> {
        const services = await Services.getInstance();
        const newClient = new WebSocketClient(url, services);
        if (!services.websocketConnection.includes(newClient)) {
            services.websocketConnection.push(newClient);
        }
    }

    public async isNewUser(): Promise<boolean> { 
        let isNew = false;
        try {
            const indexedDB = await IndexedDB.getInstance();
            const db = indexedDB.getDb();
            let userListObject = await indexedDB.getAll<User>(db, indexedDB.getStoreList().AnkUser);
            if (userListObject.length == 0) {
                isNew = true;
            }
        } catch (error) {
            console.error("Failed to retrieve isNewUser :", error);
        }               
        return isNew;
    }

    public async displayCreateId(): Promise<void> {
        const services = await Services.getInstance();
        await services.injectHtml('CREATE_ID');
        services.attachSubmitListener("form4nk", (event) => services.createId(event));
        services.attachClickListener("displayrecover", services.displayRecover);
        await services.displayProcess();
    }

    public async createId(event: Event): Promise<void> {
        event.preventDefault(); 

        const passwordElement = document.getElementById("password") as HTMLInputElement;
        const processElement = document.getElementById("selectProcess") as HTMLSelectElement;

        if (!passwordElement || !processElement) {
            console.error("One or more elements not found");
            return;
        }

        const password = passwordElement.value;
        this.current_process = processElement.value;
        console.log("JS password: " + password + " process: " + this.current_process);
        // To comment if test
        // if (!Services.instance.isPasswordValid(password)) return;

        let label = null;
        let birthday_signet = 50000;
        let birthday_main = 500000;
        const user: createUserReturn = this.sdkClient.create_user(password, label, birthday_main, birthday_signet, this.current_process);

        try {
            const indexedDb = await IndexedDB.getInstance();
            const db = indexedDb.getDb();
            await indexedDb.writeObject(db, indexedDb.getStoreList().AnkUser, user.user, null);
            await indexedDb.writeObject(db, indexedDb.getStoreList().SpOutputs, user.output_list_vec, null);
        } catch (error) {
            console.error("Failed to write user object :", error);
        }

        await Services.instance.displayRevokeImage();
    }

    public async displayRecover(): Promise<void> {
        const services = await Services.getInstance();
        await services.injectHtml('RECOVER');
        services.attachSubmitListener("form4nk", services.recover);
        services.attachClickListener("displaycreateid", services.displayCreateId);
        services.attachClickListener("displayrevoke", services.displayRevoke);
        services.attachClickListener("submitButtonRevoke", services.revoke);
        await services.displayProcess();
    }

    public async recover(event: Event) {
        event.preventDefault(); 
        console.log("JS recover submit ");

        const passwordElement = document.getElementById("password") as HTMLInputElement;
        const processElement = document.getElementById("selectProcess") as HTMLSelectElement;
        
        if (!passwordElement || !processElement) {
            console.error("One or more elements not found");
            return;
        }

        const password = passwordElement.value;
        const process = processElement.value;
        console.log("JS password: " + password + " process: " + process);
        // To comment if test
        if (!Services.instance.isPasswordValid(password)) return;

        // TODO
        alert("Recover submit to do ...");
    }

    public async displayRevokeImage(): Promise<void> {
        const services = await Services.getInstance();
        await services.injectHtml('REVOKE_IMAGE');
        services.attachClickListener("displayupdateanid", services.displayUpdateAnId);

        let imageBytes = await services.getRecoverImage('assets/4nk_revoke.jpg');
        if (imageBytes != null) {
            let blob = new Blob([imageBytes], {type: 'image/png'});
            var elem = document.getElementById("revoke") as HTMLAnchorElement;
            if (elem != null) {
                elem.href = URL.createObjectURL(blob);
            }
        }
    }

    private async getRecoverImage(imageUrl:string): Promise<Uint8Array|null> {
        let imageBytes = null;
        try {
            const response = await fetch(imageUrl);
            if (!response.ok) {
                throw new Error(`Failed to fetch image: ${response.status} ${response.statusText}`);
            }
            const arrayBuffer = await response.arrayBuffer();
            imageBytes = new Uint8Array(arrayBuffer);
        } catch (error) {
            console.error("Failed to get image : "+imageUrl, error);
        }
        return imageBytes;
    }

    public async parseBitcoinMessage(raw: Blob): Promise<string | null> {
        try {
            const buffer = await raw.arrayBuffer();
            const uint8Array = new Uint8Array(buffer);
            const msg: string = this.sdkClient.parse_bitcoin_network_msg(uint8Array);
            return msg;
        } catch (error) {
            console.error("Error processing the blob:", error);
            return null; 
        }
    }

    public async displayRevoke(): Promise<void> {
        const services = await Services.getInstance();
        services.injectHtml('REVOKE');
        services.attachClickListener("displayrecover", Services.instance.displayRecover);
        services.attachSubmitListener("form4nk", Services.instance.revoke);
    }

    public async revoke(event: Event): Promise<void> {
        event.preventDefault(); 
        console.log("JS revoke click ");
        // TODO
        alert("revoke click to do ...");
    }

    public async displayUpdateAnId() {
        const services = await Services.getInstance();

        console.log("JS displayUpdateAnId process : "+services.current_process);
        let body = "";
        let style = "";
        let script = "";
        try {
            const processObject = await services.getProcessByName("UPDATE_ID");
            if (processObject) {
                body = processObject.html;
                style = processObject.style;
                script = processObject.script;
                console.log("JS displayUpdateAnId body : "+body);

            }
        } catch (error) {
            console.error("Failed to retrieve process with Error:", error);
        }

        services.injectUpdateAnIdHtml(body, style, script);
        services.attachSubmitListener("form4nk", services.updateAnId);
    }

    public async parse4nkMessage(raw: string): Promise<string | null> {
            const msg: string = this.sdkClient.parse_4nk_msg(raw);
            return msg;
    }

    public injectUpdateAnIdHtml(bodyToInject: string, styleToInject: string, scriptToInject: string) {
        console.log("JS html : "+bodyToInject);
        const body = document.getElementsByTagName('body')[0];

        if (!body) {
            console.error("No body tag");
            return;
        }
        body.innerHTML = styleToInject + bodyToInject;

        const script = document.createElement("script");
        script.innerHTML = scriptToInject;
        document.body.appendChild(script);
        script.onload = () => {
            console.log('Script loaded successfuly');
        };
        script.onerror = () => {
            console.log('Error loading script');
        };
    }

    public async updateAnId(event: Event): Promise<void> {
        event.preventDefault(); 

        // TODO get values
        const firstNameElement = 'firstName';
        const lastNameElement = 'lastName';
        const firstName = document.getElementById(firstNameElement) as HTMLInputElement;
        const lastName = document.getElementById(lastNameElement) as HTMLInputElement;

        console.log("JS updateAnId submit ");
        // TODO
        alert("updateAnId submit to do ... Name : "+firstName.value + " "+lastName.value);

        // TODO Mock add user member to process
    }

    public async displayProcess(): Promise<void> {
        const services = await Services.getInstance();
        const processList = await services.getAllProcess();
        const selectProcess = document.getElementById("selectProcess");
        if (selectProcess) {
            processList.forEach((process) => {
                let child = new Option(process.name, process.name);
                if (!selectProcess.contains(child)) {
                    selectProcess.appendChild(child);
                }
            })
        }
    }

    public async getAllProcess(): Promise<Process[]> {
        try {
            const indexedDB = await IndexedDB.getInstance();
            const db = indexedDB.getDb();
            let processListObject = await indexedDB.getAll<Process>(db, indexedDB.getStoreList().AnkProcess);
            return processListObject;
        } catch (error) {
            console.log('getAllProcess failed: ',error);
            return [];
        }              
    }
    
    public async checkTransaction(tx: string): Promise<string | null> {
        const services = await Services.getInstance();
        try {
            return services.sdkClient.check_network_transaction(tx);
        } catch (error) {
            console.error(error);
            return null;
        }
    }

    public async getAllProcessForUser(pre_id: string): Promise<Process[]> { 
        const services = await Services.getInstance();
        let user: User;
        let userProcessList: Process[] = [];
        try {
            const indexedDB = await IndexedDB.getInstance();
            const db = indexedDB.getDb();
            user = await indexedDB.getObject<User>(db, indexedDB.getStoreList().AnkUser, pre_id);
        } catch (error) {
            console.error('getAllUserProcess failed: ',error);
            return [];
        }

        try {
            const processListObject = await services.getAllProcess();
            processListObject.forEach(async (processObject) => {
                if (processObject.members.includes(user.pre_id)) {
                    userProcessList.push(processObject);
                }
            })
        } catch (error) {
            console.error('getAllUserProcess failed: ',error);
            return [];
        }              
        return userProcessList;
    }

    public async getProcessByName(name: string): Promise<Process | null> {
        console.log('getProcessByName name: '+name);
        const indexedDB = await IndexedDB.getInstance();
        const db = indexedDB.getDb();
        const process = await indexedDB.getFirstMatchWithIndex<Process>(db, indexedDB.getStoreList().AnkProcess, 'by_name', name);
        console.log('getProcessByName process: '+process);

        return process;
    }

    public async loadProcesses(): Promise<void> { 
        const services = await Services.getInstance();
        const processList: Process[] = services.sdkClient.get_processes();
        console.error('processList size: '+processList.length);

        processList.forEach(async (process: Process) => {
            const indexedDB = await IndexedDB.getInstance();
            const db = indexedDB.getDb();
            try {
                const processStore = await indexedDB.getObject<Process>(db, indexedDB.getStoreList().AnkProcess, process.id);
                if (!processStore) {
                    console.error('Add process.id : '+process.id);
                    await indexedDB.writeObject(db, indexedDB.getStoreList().AnkProcess, process, null);
                }
            } catch (error) {
                console.warn('Error while writing process', process.name, 'to indexedDB:', error);
            }
        })
    }
    
    public attachClickListener(elementId: string, callback: (event: Event) => void): void {
        const element = document.getElementById(elementId);
        element?.removeEventListener("click", callback);
        element?.addEventListener("click", callback);
    }

    public attachSubmitListener(elementId: string, callback: (event: Event) => void): void {
        const element = document.getElementById(elementId);
        element?.removeEventListener("submit", callback);
        element?.addEventListener("submit", callback);
    }

    public async injectHtml(processName: string) {
        // console.log("JS html : "+html);
        const container = document.getElementById('containerId');

        if (!container) {
            console.error("No html container");
            return;
        }

        const services = await Services.getInstance();

        await services.loadProcesses();

        const process = await services.getProcessByName(processName);
        if (process) {
            container.innerHTML = process.html;
        } else {
            console.error("No process ", processName);
        }
    }

    // public async getCurrentProcess(): Promise<string> {
    //     let currentProcess = "";
    //     try {
    //         const indexedDB = await IndexedDB.getInstance();
    //         const db = indexedDB.getDb();
    //         currentProcess = await indexedDB.getObject<string>(db, indexedDB.getStoreList().AnkSession, Services.CURRENT_PROCESS);
    //     } catch (error) {
    //         console.error("Failed to retrieve currentprocess object :", error);
    //     }
    //     return currentProcess;
    // }
    
    public isPasswordValid(password: string) {
        var alertElem = document.getElementById("passwordalert");
        var success = true;
        var strength = 0;
        if (password.match(/[a-z]+/)) {
            var strength = 0;
            strength += 1;
        }
        if (password.match(/[A-Z]+/)) {
            strength += 1;
        }
        if (password.match(/[0-9]+/)) {
            strength += 1;
        }
        if (password.match(/[$@#&!]+/)) {
            strength += 1;
        }
        if (alertElem !== null) {
            // TODO Passer à 18
            if (password.length < 4) {
                alertElem.innerHTML = "Password size is < 4";
                success = false;
            } else {
                if (password.length > 30) {
                    alertElem.innerHTML = "Password size is > 30";
                    success = false;
                } else {
                    if (strength < 4) {
                        alertElem.innerHTML = "Password need [a-z] [A-Z] [0-9]+ [$@#&!]+";
                        success = false;
                    }
                }
            }
        }
        return success;
    }

    public obtainTokenWithFaucet(wsclient: WebSocketClient, spaddress: string): string | null {
        try {
            wsclient.sendMessage(spaddress);
        } catch (error) {
            console.error("Failed to obtain tokens with relay ", wsclient.getUrl());
            return null;
        }
        return null;
    }
}

export default Services;