import {LitElement, html, css} from 'lit';
import {customElement, property, state} from 'lit/decorators.js';
import {v4 as uuidv4} from 'uuid';

const usernameKey: string = 'username';

@customElement('username-input')
export class UsernameInput extends LitElement {
    @state() private username: string = '';

    static styles = css`
    input {
      width: 100%;
      padding: 0.75rem;
      background-color: white;
      border: 1px solid #d1d5db;
      border-radius: 0.375rem;
      box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
      font-size: 1rem;
      line-height: 1.5;
      color: #111827;
    }

    input:focus {
      outline: none;
      ring: 2px;
      ring-color: #3b82f6;
      border-color: #3b82f6;
    }
  `;

    public getCurrentUsername(): string {
        return this.username;
    }

    connectedCallback() {
        super.connectedCallback();
        this.username = this.getStoredUsername();
        this.dispatchUsernameEvent()
    }

    render() {
        return html`
      <input 
        type="text" 
        .value=${this.username}
        @input=${this.handleInput}
        placeholder="Enter your username"
        maxlength="18"
      >
    `;
    }

    private handleInput(e: Event) {
        const input = e.target as HTMLInputElement;
        this.username = input.value.trim();
        this.storeUsername(this.username);
        this.dispatchUsernameEvent()
    }

    private getStoredUsername(): string {
        const storedUsername = localStorage.getItem(usernameKey);
        if (storedUsername) {
            return storedUsername;
        }
        return this.generateNewUsername();
    }

    private storeUsername(username: string) {
        if (username) {
            localStorage.setItem(usernameKey, username);
        }
    }

    private dispatchUsernameEvent() {
        this.dispatchEvent(new CustomEvent('username-change', {
            detail: {username: this.username},
            bubbles: true,
            composed: true
        }));
    }

    private generateNewUsername(): string {
        const newUsername = "Anon" + this.uuidToThreeDigits();
        this.storeUsername(newUsername);
        return newUsername;
    }

    private uuidToThreeDigits(): string {
        const uuid = uuidv4();
        const cleanUuid = uuid.replace(/-/g, '').toLowerCase();
        const decimal = BigInt(`0x${cleanUuid}`);
        const threeDigits = decimal % 1000n;
        return threeDigits.toString().padStart(3, '0');
    }
}