/**
@license
Copyright (c) 2022 trading_peter
This program is available under Apache License Version 2.0
*/

import '@tp/tp-icon/tp-icon.js';
import { LitElement, html, css, svg } from 'lit';
import { EventHelpers } from '@tp/helpers/event-helpers.js';
import { closest } from '@tp/helpers/closest.js';

// Global stack to track opened dialogs with closeOnEsc
const dialogStack = [];
let escKeyListener = null;

// Global escape key handler
function handleGlobalEscKey(event) {
  if (event.key === 'Escape' && dialogStack.length > 0) {
    // Get the most recently opened dialog
    const lastDialog = dialogStack[dialogStack.length - 1];
    if (lastDialog && lastDialog.closeOnEsc) {
      lastDialog.close();
    }
  }
}

class TpDialog extends EventHelpers(LitElement) {
  static get styles() {
    return [
      css`
        :host {
          display: flex;
          justify-content: center;
          align-items: center;
          position: fixed;
          inset: 0px;
          pointer-events: none;
          overflow: auto;
          z-index: 900;
        }

        :host([open][modal]) {
          pointer-events: all;
        }

        dialog {
          position: relative;
          box-sizing: border-box;
          border-radius: var(--tp-dialog-border-radius);
          background-color: var(--tp-dialog-bg);
          color: var(--text);
          border: var(--tp-dialog-border);
          padding: var(--tp-dialog-padding);
          pointer-events: all;
          transform: translate(var(--tp-dialog-offset-x, 0px), var(--tp-dialog-offset-y, 0px));
          display: flex;
          flex-direction: column;
        }

        dialog:not([open]) {
          display: none;
        }

        /* Only clip/scroll once the dialog has been explicitly sized via resize. */
        :host([constrained]) dialog {
          overflow: hidden;
        }

        .scroll-wrapper {
          flex: 1;
          box-sizing: border-box;
          min-height: 0;
          overflow: visible;
        }

        :host([constrained]) .scroll-wrapper {
          overflow: auto;
        }

        .close-icon {
          position: absolute;
          right: 4px;
          top: 5px;
          z-index: 3;
          --tp-icon-width: 18px;
          --tp-icon-height: 18px;
        }

        .drag-handle {
          position: absolute;
          top: 0;
          left: 0;
          right: 0;
          height: 30px;
          cursor: move;
          z-index: 2;
        }

        .resize-handle {
          position: absolute;
          bottom: 0;
          right: 0;
          width: 14px;
          height: 14px;
          cursor: se-resize;
          z-index: 4;
          background-image: linear-gradient(135deg, transparent 0%, transparent 50%, var(--tp-dialog-resize-handle-color, #888) 50%, var(--tp-dialog-resize-handle-color, #888) 60%, transparent 60%, transparent 70%, var(--tp-dialog-resize-handle-color, #888) 70%, var(--tp-dialog-resize-handle-color, #888) 80%, transparent 80%);
          background-size: 8px 8px;
          background-repeat: no-repeat;
          background-position: bottom right;
        }
      `
    ];
  }

  render() {
    const { showClose, unmovable, resizable } = this;
    return html`
      <dialog part="dialog">
        ${!unmovable ? html`
          <div class="drag-handle" part="drag-handle" @pointerdown=${this._onDragStart}></div>
        ` : null}
        ${showClose ? html`
          <div class="close-icon" part="close-icon">
            <tp-icon .icon=${this.icon ? this.icon : TpDialog.closeIcon} dialog-dismiss></tp-icon>
          </div>
        ` : null}
        <div class="scroll-wrapper" part="scroll-wrapper">
          <slot></slot>
        </div>
        ${resizable ? html`
          <div class="resize-handle" part="resize-handle" @pointerdown=${this._onResizeStart}></div>
        ` : null}
      </dialog>
    `;
  }

  static get properties() {
    return {
      open: { type: Boolean, reflect: true },
      showClose: { type: Boolean },
      icon: { type: Object },
      closeOnEsc: { type: Boolean },
      closeOnOutsideClick: { type: Boolean },
      modal: { type: Boolean, reflect: true },
      unmovable: { type: Boolean, reflect: true },
      resizable: { type: Boolean, reflect: true },
    };
  }

  static get closeIcon() {
    return svg`<path fill="var(--tp-icon-color)" d="M20 6.91L17.09 4L12 9.09L6.91 4L4 6.91L9.09 12L4 17.09L6.91 20L12 14.91L17.09 20L20 17.09L14.91 12L20 6.91Z" />`;
  }

  get dialog() {
    return this.shadowRoot.querySelector('dialog');
  }

  constructor() {
    super();
    this._currentPromise = null;
    this._resolvePromise = null;
    this.modal = false;
    this.unmovable = false;
    this.resizable = false;
    this._offsetX = 0;
    this._offsetY = 0;
  }

  connectedCallback() {
    super.connectedCallback();
    this.listen(this, 'click', '_onDialogClick');
    this.listen(this, 'dialog-close', 'close');
    this.listen(this, 'confirmed', '_handleConfirmed');
    this.listen(this, 'dismissed', '_handleDismissed');
  }

  disconnectedCallback() {
    super.disconnectedCallback();
    this.unlisten(this, 'click', '_onDialogClick');
    this.unlisten(this, 'dialog-close', 'close');
    this.unlisten(this, 'confirmed', '_handleConfirmed');
    this.unlisten(this, 'dismissed', '_handleDismissed');
    
    // Clean up pointer drag/resize listeners
    this._cleanupActiveListeners();

    // Remove this dialog from the stack
    this._removeFromDialogStack();
    
    // Clean up promise if dialog is removed while open
    if (this._currentPromise && this._resolvePromise) {
      this._resolvePromise('dismissed');
      this._currentPromise = null;
      this._resolvePromise = null;
    }
  }

  show() {
    this.modal = false;
    this._resetPosition();
    this.dialog.show();
    this.open = true;

    // Add to dialog stack if closeOnEsc is enabled
    this._addToDialogStack();
    
    // Create and return a new promise
    this._currentPromise = new Promise((resolve) => {
      this._resolvePromise = resolve;
    });
    
    return this._currentPromise;
  }

  showModal() {
    this.modal = true;
    this._resetPosition();
    this.dialog.showModal();
    this.open = true;

    // Add to dialog stack if closeOnEsc is enabled
    this._addToDialogStack();

    if (this.closeOnOutsideClick) {
      this.addEventListener('click', this._handleOutsideClick, { once: true });
    }
    
    // Create and return a new promise
    this._currentPromise = new Promise((resolve) => {
      this._resolvePromise = resolve;
    });
    
    return this._currentPromise;
  }

  close(e) {
    if (e) {
      e.stopPropagation();
      e.preventDefault();
    }

    this.dialog.close();
    this.dispatchEvent(new CustomEvent('closed', { detail: null, bubbles: true, composed: true }));
    this.open = false;
    
    // Remove from dialog stack
    this._removeFromDialogStack();

    // Clean up pointer drag/resize listeners if they are currently active
    this._cleanupActiveListeners();

    if (this.closeOnOutsideClick) {
      this.removeEventListener('click', this._handleOutsideClick);
    }
    
    // If closed without explicit confirm/dismiss (like ESC key), treat as dismissed
    if (this._currentPromise && this._resolvePromise) {
      this._resolvePromise('dismissed');
      this._currentPromise = null;
      this._resolvePromise = null;
    }
  }

  _cleanupActiveListeners() {
    if (this._boundDragMove) {
      window.removeEventListener('pointermove', this._boundDragMove);
      this._boundDragMove = null;
    }
    if (this._boundDragEnd) {
      window.removeEventListener('pointerup', this._boundDragEnd);
      window.removeEventListener('pointercancel', this._boundDragEnd);
      this._boundDragEnd = null;
    }
    if (this._boundResizeMove) {
      window.removeEventListener('pointermove', this._boundResizeMove);
      this._boundResizeMove = null;
    }
    if (this._boundResizeEnd) {
      window.removeEventListener('pointerup', this._boundResizeEnd);
      window.removeEventListener('pointercancel', this._boundResizeEnd);
      this._boundResizeEnd = null;
    }
  }

  _resetPosition() {
    this._offsetX = 0;
    this._offsetY = 0;
    this.style.removeProperty('--tp-dialog-offset-x');
    this.style.removeProperty('--tp-dialog-offset-y');
    this.removeAttribute('constrained');
    const dialogEl = this.dialog;
    if (dialogEl) {
      dialogEl.style.removeProperty('width');
      dialogEl.style.removeProperty('height');
    }
  }

  _onDragStart(e) {
    if (this.unmovable) return;
    if (e.button !== 0) return; // Only drag with left/main pointer button

    this._startX = e.clientX;
    this._startY = e.clientY;
    this._startOffsetX = this._offsetX || 0;
    this._startOffsetY = this._offsetY || 0;

    const dragHandle = this.shadowRoot.querySelector('.drag-handle');
    if (dragHandle && typeof dragHandle.setPointerCapture === 'function') {
      dragHandle.setPointerCapture(e.pointerId);
    }

    this._boundDragMove = this._onDragMove.bind(this);
    this._boundDragEnd = this._onDragEnd.bind(this);

    window.addEventListener('pointermove', this._boundDragMove);
    window.addEventListener('pointerup', this._boundDragEnd);
    window.addEventListener('pointercancel', this._boundDragEnd);
  }

  _onDragMove(e) {
    const dx = e.clientX - this._startX;
    const dy = e.clientY - this._startY;
    this._offsetX = this._startOffsetX + dx;
    this._offsetY = this._startOffsetY + dy;

    this.style.setProperty('--tp-dialog-offset-x', `${this._offsetX}px`);
    this.style.setProperty('--tp-dialog-offset-y', `${this._offsetY}px`);
  }

  _onDragEnd(e) {
    const dragHandle = this.shadowRoot.querySelector('.drag-handle');
    if (dragHandle && typeof dragHandle.releasePointerCapture === 'function') {
      try {
        dragHandle.releasePointerCapture(e.pointerId);
      } catch (err) {}
    }

    window.removeEventListener('pointermove', this._boundDragMove);
    window.removeEventListener('pointerup', this._boundDragEnd);
    window.removeEventListener('pointercancel', this._boundDragEnd);
  }

  _onResizeStart(e) {
    if (!this.resizable) return;
    if (e.button !== 0) return; // Only resize with left/main pointer button

    e.preventDefault();
    e.stopPropagation();

    // Once the user starts resizing, content must scroll inside the fixed box.
    this.setAttribute('constrained', '');

    const rect = this.dialog.getBoundingClientRect();
    this._startWidth = rect.width;
    this._startHeight = rect.height;
    this._startX = e.clientX;
    this._startY = e.clientY;
    this._startOffsetX = this._offsetX || 0;
    this._startOffsetY = this._offsetY || 0;

    const resizeHandle = this.shadowRoot.querySelector('.resize-handle');
    if (resizeHandle && typeof resizeHandle.setPointerCapture === 'function') {
      resizeHandle.setPointerCapture(e.pointerId);
    }

    this._boundResizeMove = this._onResizeMove.bind(this);
    this._boundResizeEnd = this._onResizeEnd.bind(this);

    window.addEventListener('pointermove', this._boundResizeMove);
    window.addEventListener('pointerup', this._boundResizeEnd);
    window.addEventListener('pointercancel', this._boundResizeEnd);
  }

  _onResizeMove(e) {
    const dw = e.clientX - this._startX;
    const dh = e.clientY - this._startY;

    const newWidth = Math.max(150, this._startWidth + dw);
    const newHeight = Math.max(100, this._startHeight + dh);

    const dw_actual = newWidth - this._startWidth;
    const dh_actual = newHeight - this._startHeight;

    this._offsetX = this._startOffsetX + dw_actual / 2;
    this._offsetY = this._startOffsetY + dh_actual / 2;

    const originalTop = (window.innerHeight - newHeight) / 2;
    if (originalTop + this._offsetY < 0) {
      this._offsetY = -originalTop;
    }

    this.dialog.style.width = `${newWidth}px`;
    this.dialog.style.height = `${newHeight}px`;
    this.style.setProperty('--tp-dialog-offset-x', `${this._offsetX}px`);
    this.style.setProperty('--tp-dialog-offset-y', `${this._offsetY}px`);
  }

  _onResizeEnd(e) {
    const resizeHandle = this.shadowRoot.querySelector('.resize-handle');
    if (resizeHandle && typeof resizeHandle.releasePointerCapture === 'function') {
      try {
        resizeHandle.releasePointerCapture(e.pointerId);
      } catch (err) {}
    }

    window.removeEventListener('pointermove', this._boundResizeMove);
    window.removeEventListener('pointerup', this._boundResizeEnd);
    window.removeEventListener('pointercancel', this._boundResizeEnd);
  }

  _handleConfirmed(event) {
    if (this._currentPromise && this._resolvePromise) {
      this._resolvePromise('confirmed');
      this._currentPromise = null;
      this._resolvePromise = null;
    }
  }

  _handleDismissed(event) {
    if (this._currentPromise && this._resolvePromise) {
      this._resolvePromise('dismissed');
      this._currentPromise = null;
      this._resolvePromise = null;
    }
  }

  _addToDialogStack() {
    if (this.closeOnEsc) {
      // Remove if already in stack (shouldn't happen, but just in case)
      this._removeFromDialogStack();
      
      // Add to the end of the stack
      dialogStack.push(this);
      
      // Set up global listener if this is the first dialog
      if (dialogStack.length === 1 && !escKeyListener) {
        escKeyListener = handleGlobalEscKey;
        document.addEventListener('keydown', escKeyListener);
      }
    }
  }

  _removeFromDialogStack() {
    const index = dialogStack.indexOf(this);
    if (index > -1) {
      dialogStack.splice(index, 1);
      
      // Remove global listener if no more dialogs with closeOnEsc
      if (dialogStack.length === 0 && escKeyListener) {
        document.removeEventListener('keydown', escKeyListener);
        escKeyListener = null;
      }
    }
  }

  _onDialogClick(event) {
    if (this.closeOnOutsideClick) {
      const path = event.composedPath();
      if (!path.includes(this.dialog)) {
        this.close();
        event.stopPropagation();
        return;
      }
    }

    var rootTarget = event.composedPath()[0];
    var target = closest(rootTarget, '[dialog-dismiss]', true) || closest(rootTarget, '[dialog-confirm]', true);
    while (target && target !== this) {
      if (target.hasAttribute) {
        if (target.hasAttribute('dialog-dismiss')) {
          var reason = target.getAttribute('dialog-dismiss');
          this.dispatchEvent(new CustomEvent('dismissed', { detail: reason.length > 0 ? reason : true, bubbles: true, composed: true }));
          this.close();
          event.stopPropagation();
          break;
        } else if (target.hasAttribute('dialog-confirm')) {
          var reason = target.getAttribute('dialog-confirm');
          this.dispatchEvent(new CustomEvent('confirmed', { detail: reason.length > 0 ? reason : true, bubbles: true, composed: true }));
          this.close();
          event.stopPropagation();
          break;
        }
      }
      target = target.parentNode;
    }
  }

  _handleOutsideClick(event) {
    // This method should be implemented if closeOnOutsideClick functionality is needed
    // For now, just close the dialog when clicking outside
    this.close();
  }
}

window.customElements.define('tp-dialog', TpDialog);