import { Editor } from '../../editor/Editor.js';
import { EditorPanelDefinition } from '../../editor/editor-panel.js';
import { ContextMenuDirectory, ContextMenuEntry, ContextMenuReadOnlyEntry, ContextMenuSeparator } from '../context-menu/context-menu.js';
import { showConfirmDialog } from '../confirm-dialog/confirm-dialog.js';

interface FileNode {
  name: string;
  path: string;
  type: 'file' | 'directory';
  children?: FileNode[];
}

class FileTreePanel extends HTMLElement {
  __interfaces__ = [ EditorPanelDefinition.type ];
  selectedPath: string | null = null;
  _rootPath: string = '';
  _initialized = false;

  async connectedCallback(): Promise<void> {
    if ( this._initialized ) return;
    this._initialized = true;

    this.className = 'file-tree-panel';
    this.innerHTML = `
      <ftp-header>
        <button class="ftp-btn" data-action="add-file" title="Add file">+F</button>
        <button class="ftp-btn" data-action="add-dir" title="Add directory">+D</button>
      </ftp-header>
      <ftp-tree>Loading…</ftp-tree>
    `;

    this.querySelector( '[data-action="add-file"]' )!.addEventListener( 'click', () => this.addFile() );
    this.querySelector( '[data-action="add-dir"]' )!.addEventListener( 'click', () => this.addDirectory() );

    Editor.get().onFilesChanged.addListener( () => this.refresh() );
    Editor.get().onFileTypeUnknown.addListener( ( e ) => this._showTypeError( e.path ) );

    await this.refresh();
  }

  addContextMenuEntries( dir: ContextMenuDirectory ): void {
    dir.add( new ContextMenuReadOnlyEntry( dir, 'File Tree' ) );
  }

  _updateTabLabel(): void {
    const label = this._dirnameDisplay();
    this.dispatchEvent( new CustomEvent( 'panel:label-change', { bubbles: true, detail: { label } } ) );
  }

  _dirnameDisplay(): string {
    if ( !this._rootPath ) return '/';
    const lastSlash = this._rootPath.lastIndexOf( '/' );
    return lastSlash === -1 ? this._rootPath : this._rootPath.slice( lastSlash + 1 );
  }

  _findNode( nodes: FileNode[], targetPath: string ): FileNode | null {
    for ( const n of nodes ) {
      if ( n.path === targetPath ) return n;
      if ( n.children ) {
        const found = this._findNode( n.children, targetPath );
        if ( found ) return found;
      }
    }
    return null;
  }

  _goUp(): void {
    const lastSlash = this._rootPath.lastIndexOf( '/' );
    this._rootPath = lastSlash === -1 ? '' : this._rootPath.slice( 0, lastSlash );
    this.selectedPath = null;
    this.refresh();
  }

  async refresh(): Promise<void> {
    const state = Editor.get();
    const treeUrl = state.localRoot
      ? `/api/local/tree?root=${ encodeURIComponent( state.localRoot ) }`
      : state.remoteProject
        ? `/api/remote/files/${ state.remoteProject }/tree`
        : `/api/files/${ state.projectId }/tree`;
    const res = await fetch( treeUrl );
    const allNodes = await res.json() as FileNode[];
    const tree = this.querySelector( 'ftp-tree' )!;

    let nodes: FileNode[];

    if ( this._rootPath ) {
      const rootNode = this._findNode( allNodes, this._rootPath );
      nodes = rootNode ? ( rootNode.children ?? [] ) : [];
    }
    else {
      nodes = allNodes;
    }

    let html = '';

    if ( this._rootPath ) {
      html += `<ftp-up data-action="go-up">[ .. ]</ftp-up>`;
    }

    html += nodes.length ? this.renderNodes( nodes ) : '<ftp-empty>Empty</ftp-empty>';
    tree.innerHTML = html;

    const upBtn = tree.querySelector( '[data-action="go-up"]' );
    if ( upBtn ) {
      upBtn.addEventListener( 'click', () => this._goUp() );
    }

    this._updateTabLabel();
    this.bindTree( tree );
  }

  bindTree( tree: Element ): void {
    const state = Editor.get();
    tree.querySelectorAll( 'ftp-file' ).forEach( el => {
      el.addEventListener( 'click', async () => {
        const path = ( el as HTMLElement ).dataset.path!;
        this.selectedPath = path;
        tree.querySelectorAll( 'ftp-file, ftp-dir-label' ).forEach( f => f.classList.remove( 'active' ) );
        el.classList.add( 'active' );

        await state.fileEditorRegistry.load( state.projectId );
        const editorTag = state.fileEditorRegistry.resolve( path );

        if ( editorTag )
        {
          const containers = Array.from( document.querySelectorAll( 'tab-container' ) );

          for ( const tc of containers )
          {
            const tabs = ( tc as any ).tabs as Array<{ id: string; element: HTMLElement }>;
            for ( const tab of tabs )
            {
              if ( ( tab.element as any ).currentPath === path )
              {
                ( tc as any ).activateTab( tab.id );
                return;
              }
            }
          }

          let found: { panel: HTMLElement; tc: any; tabId: string } | null = null;

          for ( const tc of containers )
          {
            const tabs = ( tc as any ).tabs as Array<{ id: string; element: HTMLElement; dirty: boolean }>;
            for ( const tab of tabs )
            {
              if ( tab.element.tagName.toLowerCase() === editorTag && !tab.dirty && !( tab.element as any )._pinned )
              {
                found = { panel: tab.element, tc, tabId: tab.id };
                break;
              }
            }
            if ( found ) break;
          }

          if ( found )
          {
            ( found.tc as any ).activateTab( found.tabId );
            state.openDocumentIn( path, found.panel );
            return;
          }

          const panelTypeMap: Record<string, { panelType: string; label: string }> =
          {
            'page-editor-panel':   { panelType: 'page-editor',   label: 'Page Editor' },
            'code-panel':          { panelType: 'code-panel',    label: 'Code' },
            'rojo-settings-panel': { panelType: 'rojo-settings', label: 'Rojo' },
          };
          const info = panelTypeMap[ editorTag ];

          if ( info )
          {
            const targetTc = ( containers.find( tc =>
              ( tc as any ).tabs.some( ( t: any ) => t.element.tagName.toLowerCase() === editorTag )
            ) ?? document.querySelector( '[data-panel="center"] tab-container' ) ?? containers[ 0 ] ) as any;

            if ( targetTc )
            {
              const newId = info.panelType + '-' + Math.random().toString( 36 ).slice( 2 );
              targetTc.addTab( { id: newId, label: info.label, panelType: info.panelType }, () => document.createElement( editorTag ) );
              const newPanel = targetTc.tabs[ targetTc.tabs.length - 1 ].element as HTMLElement;
              state.openDocumentIn( path, newPanel );
              return;
            }
          }
        }

        state.openDocument( path );
      } );
      el.addEventListener( 'contextmenu', ( e: Event ) => {
        e.preventDefault();
        const me = e as MouseEvent;
        this.showItemMenu( ( el as HTMLElement ).dataset.path!, me.clientX, me.clientY );
      } );
    } );
    tree.querySelectorAll( 'ftp-dir-label' ).forEach( el => {
      el.addEventListener( 'click', () => {
        const dir = el.closest( 'ftp-dir' )!;
        dir.classList.toggle( 'open' );
        const path = ( el as HTMLElement ).dataset.path!;
        this.selectedPath = path;
        tree.querySelectorAll( 'ftp-file, ftp-dir-label' ).forEach( f => f.classList.remove( 'active' ) );
        el.classList.add( 'active' );
      } );
      el.addEventListener( 'dblclick', () => {
        const path = ( el as HTMLElement ).dataset.path!;
        this._rootPath = path;
        this.selectedPath = null;
        this.refresh();
      } );
      el.addEventListener( 'contextmenu', ( e: Event ) => {
        e.preventDefault();
        const me = e as MouseEvent;
        this.showItemMenu( ( el as HTMLElement ).dataset.path!, me.clientX, me.clientY );
      } );
    } );
  }

  showItemMenu( targetPath: string, x: number, y: number ): void
  {
    this.selectedPath = targetPath;
    const tree = this.querySelector( 'ftp-tree' )!;
    tree.querySelectorAll( 'ftp-file, ftp-dir-label' ).forEach( f => f.classList.remove( 'active' ) );
    tree.querySelector( `[data-path="${CSS.escape( targetPath )}"]` )?.classList.add( 'active' );

    const menu = new ContextMenuDirectory( null );
    menu.add( new ContextMenuReadOnlyEntry( menu, targetPath ) );
    menu.add( new ContextMenuSeparator( menu ) );
    menu.add( new ContextMenuEntry( menu, 'Rename…', () => this.startInlineRename( targetPath ) ) );
    menu.add( new ContextMenuEntry( menu, 'Delete', () => this.deleteEntry( targetPath ) ) );
    menu.show( x, y );
  }

  startInlineRename( oldPath: string ): void
  {
    const tree = this.querySelector( 'ftp-tree' )!;
    const lastSlash = oldPath.lastIndexOf( '/' );
    const currentName = lastSlash === -1 ? oldPath : oldPath.slice( lastSlash + 1 );

    const overlay = document.createElement( 'ftp-inline-create' );

    const input = document.createElement( 'input' );
    input.className = 'ftp-rename-input';
    input.value = currentName;
    input.type = 'text';

    overlay.innerHTML = `<ftp-inline-label>✎ Rename: ${oldPath}</ftp-inline-label>`;
    overlay.appendChild( input );

    const btnRename = document.createElement( 'button' );
    btnRename.textContent = 'Rename';
    btnRename.className = 'ftp-btn';
    const btnCancel = document.createElement( 'button' );
    btnCancel.textContent = 'Cancel';
    btnCancel.className = 'ftp-btn';

    overlay.appendChild( btnRename );
    overlay.appendChild( btnCancel );
    tree.prepend( overlay );
    input.focus();
    input.select();

    const confirm = async () =>
    {
      const newName = input.value.trim();
      if ( !newName || newName === currentName ) { overlay.remove(); return; }
      await this.renameEntry( oldPath, newName );
      overlay.remove();
    };

    const cancel = () => overlay.remove();

    btnRename.addEventListener( 'click', confirm );
    btnCancel.addEventListener( 'click', cancel );
    input.addEventListener( 'keydown', ( e: KeyboardEvent ) =>
    {
      if ( 'Enter' === e.key ) confirm();
      if ( 'Escape' === e.key ) cancel();
    } );
  }

  async renameEntry( oldPath: string, newName: string ): Promise<void>
  {
    const state = Editor.get();
    const body = state.localRoot
      ? { root: state.localRoot, path: oldPath, newName }
      : { path: oldPath, newName };
    const url = state.localRoot
      ? `/api/local/rename`
      : state.remoteProject
        ? `/api/remote/files/${ state.remoteProject }/rename`
        : `/api/files/${ state.projectId }/rename`;
    const res = await fetch( url, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify( body ),
    } );

    if ( !res.ok ) return;

    const lastSlash = oldPath.lastIndexOf( '/' );
    const parent = lastSlash === -1 ? '' : oldPath.slice( 0, lastSlash );
    this.selectedPath = parent ? `${parent}/${newName}` : newName;
    Editor.get().onFilesChanged.dispatch();
  }

  async deleteEntry( targetPath: string ): Promise<void>
  {
    const lastSlash = targetPath.lastIndexOf( '/' );
    const name = lastSlash === -1 ? targetPath : targetPath.slice( lastSlash + 1 );
    const confirmed = await showConfirmDialog( {
      icon: '🗑',
      title: 'Delete',
      message: `Delete "${name}"? This cannot be undone.`,
      confirmLabel: 'Delete',
      cancelLabel: 'Cancel',
      danger: true,
    } );

    if ( !confirmed ) return;

    const state = Editor.get();
    const body = state.localRoot
      ? { root: state.localRoot, path: targetPath }
      : { path: targetPath };
    const url = state.localRoot
      ? `/api/local/delete`
      : state.remoteProject
        ? `/api/remote/files/${ state.remoteProject }/delete`
        : `/api/files/${ state.projectId }/delete`;
    const res = await fetch( url, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify( body ),
    } );

    if ( !res.ok ) return;

    if ( this.selectedPath === targetPath ) this.selectedPath = null;
    Editor.get().onFilesChanged.dispatch();
  }

  resolveTargetDir(): string {
    if ( !this.selectedPath ) return this._rootPath;

    const tree = this.querySelector( 'ftp-tree' )!;
    const dirLabel = tree.querySelector( `ftp-dir-label[data-path="${CSS.escape( this.selectedPath )}"]` );
    if ( dirLabel ) return this.selectedPath;

    const lastSlash = this.selectedPath.lastIndexOf( '/' );
    return lastSlash === -1 ? this._rootPath : this.selectedPath.slice( 0, lastSlash );
  }

  async addFile(): Promise<void> {
    const state = Editor.get();
    const dir = this.resolveTargetDir();
    const name = await this.findFreeName(state.projectId, dir, 'file', 'txt');
    const filePath = dir ? `${dir}/${name}` : name;
    this.startInlineCreate(filePath, 'file', name);
  }

  async addDirectory(): Promise<void> {
    const state = Editor.get();
    const dir = this.resolveTargetDir();
    const name = await this.findFreeName(state.projectId, dir, 'directory', '');
    const dirPath = dir ? `${dir}/${name}` : name;
    this.startInlineCreate(dirPath, 'directory', name);
  }

  async findFreeName(projectId: string, dir: string, type: 'file' | 'directory', ext: string): Promise<string> {
    const baseName = type === 'file' ? 'file' : 'directory';
    const state = Editor.get();
    const treeUrl = state.localRoot
      ? `/api/local/tree?root=${ encodeURIComponent( state.localRoot ) }`
      : state.remoteProject
        ? `/api/remote/files/${ state.remoteProject }/tree`
        : `/api/files/${ projectId }/tree`;
    const res = await fetch( treeUrl );
    const tree = await res.json() as FileNode[];
    for (let i = 1; i <= 999; i++) {
      const name = ext ? `${baseName}${i > 1 ? i : ''}.${ext}` : `${baseName}${i > 1 ? i : ''}`;
      const testPath = dir ? `${dir}/${name}` : name;
      if (!this.pathExistsInTree(tree, testPath)) return name;
    }
    return `${baseName}-${Date.now()}${ext ? '.' + ext : ''}`;
  }

  pathExistsInTree(nodes: FileNode[], targetPath: string): boolean {
    for (const n of nodes) {
      if (n.path === targetPath) return true;
      if (n.children && this.pathExistsInTree(n.children, targetPath)) return true;
    }
    return false;
  }

  startInlineCreate(fullPath: string, type: 'file' | 'directory', defaultName: string): void {
    const tree = this.querySelector('ftp-tree')!;
    const overlay = document.createElement('ftp-inline-create');

    const input = document.createElement('input');
    input.className = 'ftp-rename-input';
    input.value = defaultName;
    input.type = 'text';

    overlay.innerHTML = `<ftp-inline-label>${type === 'file' ? '📄' : '📁'} New ${type} in: ${fullPath.includes('/') ? fullPath.slice(0, fullPath.lastIndexOf('/')) || '/' : '/'}</ftp-inline-label>`;
    overlay.appendChild(input);

    const btnCreate = document.createElement('button');
    btnCreate.textContent = 'Create';
    btnCreate.className = 'ftp-btn';
    const btnCancel = document.createElement('button');
    btnCancel.textContent = 'Cancel';
    btnCancel.className = 'ftp-btn';

    overlay.appendChild(btnCreate);
    overlay.appendChild(btnCancel);
    tree.prepend(overlay);
    input.focus();
    input.select();

    const confirm = async () => {
      const name = input.value.trim();
      if (!name) return;
      const dir = fullPath.includes('/') ? fullPath.slice(0, fullPath.lastIndexOf('/')) : '';
      const finalPath = dir ? `${dir}/${name}` : name;
      await this.createEntry(type, finalPath);
      overlay.remove();
    };

    const cancel = () => overlay.remove();

    btnCreate.addEventListener('click', confirm);
    btnCancel.addEventListener('click', cancel);
    input.addEventListener('keydown', (e: KeyboardEvent) => {
      if (e.key === 'Enter') confirm();
      if (e.key === 'Escape') cancel();
    });
  }

  async createEntry(type: 'file' | 'directory', path: string): Promise<void> {
    const state = Editor.get();
    const endpoint = type === 'file' ? 'create-file' : 'create-directory';
    const body = state.localRoot
      ? { root: state.localRoot, path }
      : { path };
    const url = state.localRoot
      ? `/api/local/${ endpoint }`
      : state.remoteProject
        ? `/api/remote/files/${ state.remoteProject }/${ endpoint }`
        : `/api/files/${ state.projectId }/${ endpoint }`;
    const res = await fetch( url, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify( body ),
    } );
    if ( res.ok )
    {
      if ( type === 'file' )
      {
        this.selectedPath = path;
      }

      Editor.get().onFilesChanged.dispatch();
    }
  }

  renderNodes(nodes: FileNode[], depth = 0): string {
    const dirIcon = `<img class="ftp-icon" src="/icons/directory.svg" alt="">`;
    const fileIcon = `<img class="ftp-icon" src="/icons/file.svg" alt="">`;
    const sorted = [ ...nodes ].sort( ( a, b ) => a.type === b.type ? 0 : a.type === 'directory' ? -1 : 1 );
    return `<ftp-list style="--depth:${depth}">` + sorted.map(n => {
      if (n.type === 'directory') {
        return `<ftp-dir>
          <ftp-dir-label data-path="${n.path}">${dirIcon}${n.name}</ftp-dir-label>
          ${this.renderNodes(n.children ?? [], depth + 1)}
        </ftp-dir>`;
      }
      return `<ftp-file data-path="${n.path}">${fileIcon}${n.name}</ftp-file>`;
    }).join('') + '</ftp-list>';
  }

  _showTypeError( filePath: string ): void
  {
    const lastDot = filePath.lastIndexOf( '.' );
    const ext = lastDot === -1 ? '' : filePath.slice( lastDot );
    const msg = ext ? `Can't open extension "${ext}"` : `Can't open file without extension`;

    const tree = this.querySelector( 'ftp-tree' )!;
    const existing = tree.querySelector( 'ftp-type-error' );
    if ( existing ) existing.remove();

    const el = document.createElement( 'ftp-type-error' );
    el.textContent = msg;
    tree.prepend( el );

    setTimeout( () => el.remove(), 3000 );
  }
}

customElements.define('file-tree-panel', FileTreePanel);