import {
  customElement,
  property,
  static as html,
  DeesElement,
  type TemplateResult,
  cssManager,
  css,
  query,
} from '@design.estate/dees-element';

import { type IBlock } from './wysiwyg.types.js';
import { WysiwygBlocks } from './wysiwyg.blocks.js';
import { WysiwygSelection } from './wysiwyg.selection.js';

declare global {
  interface HTMLElementTagNameMap {
    'dees-wysiwyg-block': DeesWysiwygBlock;
  }
}

@customElement('dees-wysiwyg-block')
export class DeesWysiwygBlock extends DeesElement {
  @property({ type: Object })
  public block: IBlock;

  @property({ type: Boolean })
  public isSelected: boolean = false;

  @property({ type: Object })
  public handlers: {
    onInput: (e: InputEvent) => void;
    onKeyDown: (e: KeyboardEvent) => void;
    onFocus: () => void;
    onBlur: () => void;
    onCompositionStart: () => void;
    onCompositionEnd: () => void;
    onMouseUp?: (e: MouseEvent) => void;
  };

  @query('.block')
  private blockElement: HTMLDivElement;
  
  // Track if we've initialized the content
  private contentInitialized: boolean = false;

  public static styles = [
    cssManager.defaultStyles,
    css`
      :host {
        display: block;
      }

      .block {
        padding: 4px 0;
        min-height: 1.6em;
        outline: none;
        width: 100%;
        word-wrap: break-word;
        position: relative;
        transition: all 0.15s ease;
        color: ${cssManager.bdTheme('#000000', '#e0e0e0')};
      }

      .block:empty:not(:focus)::before {
        content: attr(data-placeholder);
        color: ${cssManager.bdTheme('#999', '#666')};
        position: absolute;
        pointer-events: none;
      }

      .block.heading-1 {
        font-size: 32px;
        font-weight: 700;
        line-height: 1.2;
        margin: 24px 0 8px 0;
        color: ${cssManager.bdTheme('#000000', '#ffffff')};
      }

      .block.heading-2 {
        font-size: 24px;
        font-weight: 600;
        line-height: 1.3;
        margin: 20px 0 6px 0;
        color: ${cssManager.bdTheme('#000000', '#ffffff')};
      }

      .block.heading-3 {
        font-size: 20px;
        font-weight: 600;
        line-height: 1.4;
        margin: 16px 0 4px 0;
        color: ${cssManager.bdTheme('#000000', '#ffffff')};
      }

      .block.quote {
        border-left: 3px solid ${cssManager.bdTheme('#0066cc', '#4d94ff')};
        padding-left: 20px;
        color: ${cssManager.bdTheme('#555', '#b0b0b0')};
        font-style: italic;
        line-height: 1.6;
        margin: 16px 0;
      }

      .block.code {
        font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Fira Code', monospace;
        font-size: 14px;
        background: ${cssManager.bdTheme('#f8f8f8', '#0d0d0d')};
        border: 1px solid ${cssManager.bdTheme('#e0e0e0', '#2a2a2a')};
        padding: 16px 20px;
        padding-top: 32px;
        border-radius: 6px;
        white-space: pre-wrap;
        color: ${cssManager.bdTheme('#24292e', '#e1e4e8')};
        line-height: 1.5;
        overflow-x: auto;
        margin: 20px 0;
      }

      .block.list {
        padding: 0;
      }

      .block.list ul,
      .block.list ol {
        margin: 0;
        padding-left: 24px;
      }

      .block.list li {
        margin: 4px 0;
      }

      .block.divider {
        padding: 0;
        margin: 16px 0;
        pointer-events: none;
      }

      .block.divider hr {
        border: none;
        border-top: 1px solid ${cssManager.bdTheme('#e0e0e0', '#333')};
        margin: 0;
      }

      /* Formatting styles */
      .block :is(b, strong) {
        font-weight: 600;
        color: ${cssManager.bdTheme('#000000', '#ffffff')};
      }

      .block :is(i, em) {
        font-style: italic;
      }

      .block u {
        text-decoration: underline;
      }

      .block s {
        text-decoration: line-through;
      }

      .block code {
        font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Fira Code', monospace;
        font-size: 0.9em;
        background: ${cssManager.bdTheme('rgba(0, 0, 0, 0.06)', 'rgba(255, 255, 255, 0.1)')};
        padding: 2px 6px;
        border-radius: 3px;
        color: ${cssManager.bdTheme('#d14', '#ff6b6b')};
      }

      .block a {
        color: ${cssManager.bdTheme('#0066cc', '#4d94ff')};
        text-decoration: none;
        border-bottom: 1px solid transparent;
        transition: border-color 0.15s ease;
        cursor: pointer;
      }

      .block a:hover {
        border-bottom-color: ${cssManager.bdTheme('#0066cc', '#4d94ff')};
      }

      .code-language {
        position: absolute;
        top: 0;
        right: 0;
        background: ${cssManager.bdTheme('#e1e4e8', '#333333')};
        color: ${cssManager.bdTheme('#586069', '#8b949e')};
        padding: 4px 12px;
        font-size: 12px;
        border-radius: 0 6px 0 6px;
        font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
        text-transform: lowercase;
        z-index: 1;
      }

      .code-block-container {
        position: relative;
        margin: 20px 0;
      }

      /* Selection styles */
      .block ::selection {
        background: ${cssManager.bdTheme('rgba(0, 102, 204, 0.3)', 'rgba(77, 148, 255, 0.3)')};
        color: inherit;
      }

      /* Paragraph specific styles */
      .block.paragraph {
        font-size: 16px;
        line-height: 1.6;
        font-weight: 400;
      }

      /* Strike through */
      .block :is(s, strike) {
        text-decoration: line-through;
        opacity: 0.7;
      }

      /* List specific margin adjustments */
      .block.list li {
        margin-bottom: 8px;
        line-height: 1.6;
      }

      .block.list li:last-child {
        margin-bottom: 0;
      }

      /* Block margin adjustments based on type */
      :host-context(.block-wrapper:first-child) .block {
        margin-top: 0 !important;
      }

      :host-context(.block-wrapper:last-child) .block {
        margin-bottom: 0;
      }

      /* Selected state */
      .block.selected {
        background: ${cssManager.bdTheme('rgba(0, 102, 204, 0.05)', 'rgba(77, 148, 255, 0.08)')};
        box-shadow: inset 0 0 0 2px ${cssManager.bdTheme('rgba(0, 102, 204, 0.2)', 'rgba(77, 148, 255, 0.2)')};
        border-radius: 4px;
        margin-left: -8px;
        margin-right: -8px;
        padding-left: 8px;
        padding-right: 8px;
      }
    `,
  ];

  protected shouldUpdate(changedProperties: Map<string, any>): boolean {
    // Never update if only the block content changed
    if (changedProperties.has('block') && this.block) {
      const oldBlock = changedProperties.get('block');
      if (oldBlock && oldBlock.id === this.block.id && oldBlock.type === this.block.type) {
        // Only content or metadata changed, don't re-render
        return false;
      }
    }
    
    // Only update if the block type or id changes
    return !this.blockElement || this.block?.type !== this.blockElement.dataset.blockType;
  }
  
  public firstUpdated(): void {
    // Mark that content has been initialized
    this.contentInitialized = true;
    
    // For code blocks, the actual contenteditable block is nested
    const editableBlock = this.block.type === 'code' 
      ? this.shadowRoot?.querySelector('.block.code') as HTMLDivElement
      : this.blockElement;
    
    // Ensure the block element maintains its content
    if (editableBlock) {
      editableBlock.setAttribute('data-block-id', this.block.id);
      editableBlock.setAttribute('data-block-type', this.block.type);
      
      // Set up all event handlers manually to avoid Lit re-renders
      editableBlock.addEventListener('input', (e) => {
        this.logCursorPosition('input');
        this.handlers?.onInput?.(e as InputEvent);
      });
      
      editableBlock.addEventListener('keydown', (e) => {
        this.handlers?.onKeyDown?.(e);
      });
      
      editableBlock.addEventListener('keyup', (e) => {
        this.logCursorPosition('keyup', e);
      });
      
      editableBlock.addEventListener('focus', () => {
        this.handlers?.onFocus?.();
      });
      
      editableBlock.addEventListener('blur', () => {
        this.handlers?.onBlur?.();
      });
      
      editableBlock.addEventListener('compositionstart', () => {
        this.handlers?.onCompositionStart?.();
      });
      
      editableBlock.addEventListener('compositionend', () => {
        this.handlers?.onCompositionEnd?.();
      });
      
      editableBlock.addEventListener('mouseup', (e) => {
        this.logCursorPosition('mouseup');
        this.handleMouseUp(e);
        this.handlers?.onMouseUp?.(e);
      });
      
      editableBlock.addEventListener('click', () => {
        this.logCursorPosition('click');
      });
      
      // Set initial content if needed
      if (this.block.content) {
        if (this.block.type === 'code') {
          editableBlock.textContent = this.block.content;
        } else if (this.block.type === 'list') {
          editableBlock.innerHTML = WysiwygBlocks.renderListContent(this.block.content, this.block.metadata);
        } else {
          editableBlock.innerHTML = this.block.content;
        }
      }
    }
    
    // Update blockElement reference for code blocks
    if (this.block.type === 'code') {
      this.blockElement = editableBlock;
    }
  }

  render(): TemplateResult {
    if (!this.block) return html``;

    if (this.block.type === 'divider') {
      return html`
        <div class="block divider" data-block-id="${this.block.id}" data-block-type="${this.block.type}">
          <hr>
        </div>
      `;
    }

    if (this.block.type === 'code') {
      const language = this.block.metadata?.language || 'plain text';
      return html`
        <div class="code-block-container">
          <div class="code-language">${language}</div>
          <div
            class="block code ${this.isSelected ? 'selected' : ''}"
            contenteditable="true"
            data-block-type="${this.block.type}"
          ></div>
        </div>
      `;
    }

    const placeholder = this.getPlaceholder();
    
    // Return static HTML without event bindings
    return html`
      <div
        class="block ${this.block.type} ${this.isSelected ? 'selected' : ''}"
        contenteditable="true"
        data-placeholder="${placeholder}"
      ></div>
    `;
  }

  private getPlaceholder(): string {
    switch (this.block.type) {
      case 'paragraph':
        return "Type '/' for commands...";
      case 'heading-1':
        return 'Heading 1';
      case 'heading-2':
        return 'Heading 2';
      case 'heading-3':
        return 'Heading 3';
      case 'quote':
        return 'Quote';
      default:
        return '';
    }
  }


  public focus(): void {
    if (!this.blockElement) return;
    
    // Ensure the element is focusable
    if (!this.blockElement.hasAttribute('contenteditable')) {
      this.blockElement.setAttribute('contenteditable', 'true');
    }
    
    this.blockElement.focus();
    
    // If focus failed, try again after a microtask
    if (document.activeElement !== this.blockElement) {
      Promise.resolve().then(() => {
        this.blockElement.focus();
      });
    }
  }
  
  public focusWithCursor(position: 'start' | 'end' | number = 'end'): void {
    if (!this.blockElement) return;
    
    // Ensure element is focusable first
    if (!this.blockElement.hasAttribute('contenteditable')) {
      this.blockElement.setAttribute('contenteditable', 'true');
    }
    
    // Focus the element
    this.blockElement.focus();
    
    // Set cursor position after focus is established
    const setCursor = () => {
      if (position === 'start') {
        this.setCursorToStart();
      } else if (position === 'end') {
        this.setCursorToEnd();
      } else if (typeof position === 'number') {
        // Use the new selection utility to set cursor position
        WysiwygSelection.setCursorPosition(this.blockElement, position);
      }
    };
    
    // Ensure cursor is set after focus
    if (document.activeElement === this.blockElement) {
      setCursor();
    } else {
      // Wait for focus to be established
      Promise.resolve().then(() => {
        if (document.activeElement === this.blockElement) {
          setCursor();
        }
      });
    }
  }
  
  private getFirstTextNode(node: Node): Text | null {
    if (node.nodeType === Node.TEXT_NODE) {
      return node as Text;
    }
    
    for (let i = 0; i < node.childNodes.length; i++) {
      const textNode = this.getFirstTextNode(node.childNodes[i]);
      if (textNode) return textNode;
    }
    
    return null;
  }

  public getContent(): string {
    if (!this.blockElement) return '';
    
    if (this.block.type === 'list') {
      const listItems = this.blockElement.querySelectorAll('li');
      return Array.from(listItems).map(li => li.innerHTML || '').join('\n');
    } else if (this.block.type === 'code') {
      return this.blockElement.textContent || '';
    } else {
      return this.blockElement.innerHTML || '';
    }
  }

  public setContent(content: string): void {
    if (!this.blockElement) return;
    
    // Store if we have focus
    const hadFocus = document.activeElement === this.blockElement;
    
    if (this.block.type === 'list') {
      this.blockElement.innerHTML = WysiwygBlocks.renderListContent(content, this.block.metadata);
    } else if (this.block.type === 'code') {
      this.blockElement.textContent = content;
    } else {
      this.blockElement.innerHTML = content;
    }
    
    // Restore focus if we had it
    if (hadFocus) {
      this.blockElement.focus();
    }
  }

  public setCursorToStart(): void {
    WysiwygBlocks.setCursorToStart(this.blockElement);
  }

  public setCursorToEnd(): void {
    WysiwygBlocks.setCursorToEnd(this.blockElement);
  }

  public focusListItem(): void {
    if (this.block.type === 'list') {
      WysiwygBlocks.focusListItem(this.blockElement);
    }
  }
  
  /**
   * Gets content split at cursor position
   */
  public getSplitContent(): { before: string; after: string } | null {
    if (!this.blockElement) return null;
    
    // Get the full content first
    const fullContent = this.getContent();
    console.log('getSplitContent: Full content:', {
      content: fullContent,
      length: fullContent.length,
      blockType: this.block.type
    });
    
    // Get selection info using the new utility that handles Shadow DOM
    const selectionInfo = WysiwygSelection.getSelectionInfo(this.shadowRoot!);
    if (!selectionInfo) {
      console.log('getSplitContent: No selection, returning all content as before');
      return {
        before: fullContent,
        after: ''
      };
    }
    
    // Check if selection is within this block
    if (!WysiwygSelection.isSelectionInElement(this.blockElement, this.shadowRoot!)) {
      console.log('getSplitContent: Selection not in this block');
      return null;
    }
    
    // Get cursor position as a number
    const cursorPosition = WysiwygSelection.getCursorPositionInElement(this.blockElement, this.shadowRoot!);
    console.log('getSplitContent: Cursor position:', {
      cursorPosition,
      contentLength: fullContent.length,
      startContainer: selectionInfo.startContainer,
      startOffset: selectionInfo.startOffset,
      collapsed: selectionInfo.collapsed
    });
    
    // Handle special cases for different block types
    if (this.block.type === 'code') {
      // For code blocks, split text content
      const fullText = this.blockElement.textContent || '';
      const textNode = this.getFirstTextNode(this.blockElement);
      
      if (textNode && selectionInfo.startContainer === textNode) {
        const before = fullText.substring(0, selectionInfo.startOffset);
        const after = fullText.substring(selectionInfo.startOffset);
        
        console.log('getSplitContent: Code block split result:', {
          cursorPosition,
          contentLength: fullText.length,
          beforeContent: before,
          beforeLength: before.length,
          afterContent: after,
          afterLength: after.length,
          startOffset: selectionInfo.startOffset
        });
        
        return { before, after };
      }
    }
    
    // For other block types, extract HTML content
    try {
      // Create a temporary range to get content before cursor
      const beforeRange = document.createRange();
      beforeRange.selectNodeContents(this.blockElement);
      beforeRange.setEnd(selectionInfo.startContainer, selectionInfo.startOffset);
      
      // Create a temporary range to get content after cursor
      const afterRange = document.createRange();
      afterRange.selectNodeContents(this.blockElement);
      afterRange.setStart(selectionInfo.startContainer, selectionInfo.startOffset);
      
      // Clone HTML content (not extract, to avoid modifying the DOM)
      const beforeContents = beforeRange.cloneContents();
      const afterContents = afterRange.cloneContents();
      
      // Convert to HTML strings
      const tempDiv = document.createElement('div');
      tempDiv.appendChild(beforeContents);
      const beforeHtml = tempDiv.innerHTML;
      
      tempDiv.innerHTML = '';
      tempDiv.appendChild(afterContents);
      const afterHtml = tempDiv.innerHTML;
      
      const result = {
        before: beforeHtml,
        after: afterHtml
      };
      
      console.log('getSplitContent: Split result:', {
        cursorPosition,
        contentLength: fullContent.length,
        beforeContent: result.before,
        beforeLength: result.before.length,
        afterContent: result.after,
        afterLength: result.after.length
      });
      
      return result;
    } catch (error) {
      console.error('Error splitting content:', error);
      // Fallback: return all content as "before"
      const fallbackResult = {
        before: this.getContent(),
        after: ''
      };
      
      console.log('getSplitContent: Fallback result:', {
        beforeContent: fallbackResult.before,
        beforeLength: fallbackResult.before.length,
        afterContent: fallbackResult.after,
        afterLength: fallbackResult.after.length
      });
      
      return fallbackResult;
    }
  }
  
  private handleMouseUp(_e: MouseEvent): void {
    // Check if we have a selection within this block
    setTimeout(() => {
      const selection = window.getSelection();
      if (selection && selection.rangeCount > 0) {
        const range = selection.getRangeAt(0);
        
        // Check if selection is within this block
        if (this.blockElement && this.blockElement.contains(range.commonAncestorContainer)) {
          const selectedText = selection.toString();
          if (selectedText.length > 0) {
            // Dispatch a custom event that can cross shadow DOM boundaries
            this.dispatchEvent(new CustomEvent('block-text-selected', {
              detail: { 
                text: selectedText,
                blockId: this.block.id,
                range: range
              },
              bubbles: true,
              composed: true
            }));
          }
        }
      }
    }, 10);
  }
  
  /**
   * Logs cursor position for debugging
   */
  private logCursorPosition(eventType: string, event?: KeyboardEvent): void {
    console.log(`[CursorLog] Event triggered: ${eventType} in block ${this.block.id}`);
    
    // Get the actual active element considering shadow DOM
    const activeElement = this.shadowRoot?.activeElement;
    console.log(`[CursorLog] Active element:`, activeElement, 'Block element:', this.blockElement);
    
    // Only log if this block is focused
    if (activeElement !== this.blockElement) {
      console.log(`[CursorLog] Block not focused, skipping detailed logging`);
      return;
    }
    
    // Get selection info using the new utility that handles Shadow DOM
    const selectionInfo = WysiwygSelection.getSelectionInfo(this.shadowRoot!);
    if (!selectionInfo) {
      console.log(`[${eventType}] No selection available`);
      return;
    }
    
    const isInThisBlock = WysiwygSelection.isSelectionInElement(this.blockElement, this.shadowRoot!);
    
    if (!isInThisBlock) {
      return;
    }
    
    // Get cursor position details
    const details: any = {
      event: eventType,
      blockId: this.block.id,
      blockType: this.block.type,
      collapsed: selectionInfo.collapsed,
      startContainer: {
        nodeType: selectionInfo.startContainer.nodeType,
        nodeName: selectionInfo.startContainer.nodeName,
        textContent: selectionInfo.startContainer.textContent?.substring(0, 50) + '...',
      },
      startOffset: selectionInfo.startOffset,
    };
    
    // Add key info if it's a keyboard event
    if (event) {
      details.key = event.key;
      details.shiftKey = event.shiftKey;
      details.ctrlKey = event.ctrlKey;
      details.metaKey = event.metaKey;
    }
    
    // Try to get the actual cursor position in the text
    if (selectionInfo.startContainer.nodeType === Node.TEXT_NODE) {
      const textNode = selectionInfo.startContainer as Text;
      const textBefore = textNode.textContent?.substring(0, selectionInfo.startOffset) || '';
      const textAfter = textNode.textContent?.substring(selectionInfo.startOffset) || '';
      
      details.cursorPosition = {
        textBefore: textBefore.slice(-20), // Last 20 chars before cursor
        textAfter: textAfter.slice(0, 20),  // First 20 chars after cursor
        totalLength: textNode.textContent?.length || 0,
        offset: selectionInfo.startOffset
      };
    }
    
    // Check if we're at boundaries
    details.boundaries = {
      atStart: this.isCursorAtStart(selectionInfo),
      atEnd: this.isCursorAtEnd(selectionInfo)
    };
    
    console.log('Cursor Position:', details);
  }
  
  /**
   * Check if cursor is at the start of the block
   */
  private isCursorAtStart(selectionInfo: { startContainer: Node; startOffset: number; collapsed: boolean }): boolean {
    if (!selectionInfo.collapsed || selectionInfo.startOffset !== 0) return false;
    
    const firstNode = this.getFirstTextNode(this.blockElement);
    return !firstNode || selectionInfo.startContainer === firstNode || selectionInfo.startContainer === this.blockElement;
  }
  
  /**
   * Check if cursor is at the end of the block
   */
  private isCursorAtEnd(selectionInfo: { endContainer: Node; endOffset: number; collapsed: boolean }): boolean {
    if (!selectionInfo.collapsed) return false;
    
    const lastNode = this.getLastTextNode(this.blockElement);
    if (!lastNode) return true;
    
    return selectionInfo.endContainer === lastNode && 
           selectionInfo.endOffset === (lastNode.textContent?.length || 0);
  }
  
  /**
   * Get the last text node in the element
   */
  private getLastTextNode(node: Node): Text | null {
    if (node.nodeType === Node.TEXT_NODE) {
      return node as Text;
    }
    
    for (let i = node.childNodes.length - 1; i >= 0; i--) {
      const lastText = this.getLastTextNode(node.childNodes[i]);
      if (lastText) return lastText;
    }
    
    return null;
  }
}