import * as plugins from '../plugins.js';
import { apiService } from '../services/index.js';

const { html, css, cssManager, customElement, property, state, DeesElement } = plugins;

@customElement('tsview-s3-preview')
export class TsviewS3Preview extends DeesElement {
  @property({ type: String })
  public accessor bucketName: string = '';

  @property({ type: String })
  public accessor objectKey: string = '';

  @state()
  private accessor loading: boolean = false;

  @state()
  private accessor content: string = '';

  @state()
  private accessor contentType: string = '';

  @state()
  private accessor size: number = 0;

  @state()
  private accessor lastModified: string = '';

  @state()
  private accessor error: string = '';

  public static styles = [
    cssManager.defaultStyles,
    css`
      :host {
        display: block;
        height: 100%;
      }

      .preview-container {
        display: flex;
        flex-direction: column;
        height: 100%;
      }

      .preview-header {
        padding: 12px;
        border-bottom: 1px solid #333;
      }

      .preview-title {
        font-size: 14px;
        font-weight: 500;
        margin-bottom: 8px;
        word-break: break-all;
      }

      .preview-meta {
        display: flex;
        flex-wrap: wrap;
        gap: 16px;
        font-size: 12px;
        color: #888;
      }

      .meta-item {
        display: flex;
        align-items: center;
        gap: 4px;
      }

      .preview-content {
        flex: 1;
        overflow: auto;
        padding: 12px;
      }

      .preview-image {
        max-width: 100%;
        max-height: 100%;
        object-fit: contain;
        border-radius: 4px;
      }

      .preview-text {
        font-family: 'Monaco', 'Menlo', monospace;
        font-size: 12px;
        line-height: 1.5;
        white-space: pre-wrap;
        word-break: break-all;
        color: #ccc;
        background: rgba(0, 0, 0, 0.3);
        padding: 12px;
        border-radius: 6px;
      }

      .preview-actions {
        padding: 12px;
        border-top: 1px solid #333;
        display: flex;
        gap: 8px;
      }

      .action-btn {
        flex: 1;
        padding: 8px 16px;
        background: rgba(99, 102, 241, 0.2);
        border: 1px solid #6366f1;
        color: #818cf8;
        border-radius: 6px;
        cursor: pointer;
        font-size: 13px;
        transition: all 0.15s;
      }

      .action-btn:hover {
        background: rgba(99, 102, 241, 0.3);
      }

      .action-btn.danger {
        background: rgba(239, 68, 68, 0.2);
        border-color: #ef4444;
        color: #f87171;
      }

      .action-btn.danger:hover {
        background: rgba(239, 68, 68, 0.3);
      }

      .empty-state {
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        height: 100%;
        color: #666;
        text-align: center;
        padding: 24px;
      }

      .empty-state svg {
        width: 48px;
        height: 48px;
        margin-bottom: 12px;
        opacity: 0.5;
      }

      .loading-state {
        display: flex;
        align-items: center;
        justify-content: center;
        height: 100%;
        color: #888;
      }

      .error-state {
        padding: 16px;
        color: #f87171;
        text-align: center;
      }

      .binary-preview {
        text-align: center;
        color: #888;
        padding: 24px;
      }
    `,
  ];

  updated(changedProperties: Map<string, unknown>) {
    if (changedProperties.has('objectKey') || changedProperties.has('bucketName')) {
      if (this.objectKey) {
        this.loadObject();
      } else {
        this.content = '';
        this.contentType = '';
      }
    }
  }

  private async loadObject() {
    if (!this.objectKey || !this.bucketName) return;

    this.loading = true;
    this.error = '';

    try {
      const result = await apiService.getObject(this.bucketName, this.objectKey);
      this.content = result.content;
      this.contentType = result.contentType;
      this.size = result.size;
      this.lastModified = result.lastModified;
    } catch (err) {
      console.error('Error loading object:', err);
      this.error = 'Failed to load object';
    }

    this.loading = false;
  }

  private getFileName(path: string): string {
    const parts = path.split('/');
    return parts[parts.length - 1] || path;
  }

  private formatSize(bytes: number): string {
    const units = ['B', 'KB', 'MB', 'GB', 'TB'];
    let size = bytes;
    let unitIndex = 0;
    while (size >= 1024 && unitIndex < units.length - 1) {
      size /= 1024;
      unitIndex++;
    }
    return `${size.toFixed(unitIndex > 0 ? 1 : 0)} ${units[unitIndex]}`;
  }

  private formatDate(dateStr: string): string {
    if (!dateStr) return '-';
    const date = new Date(dateStr);
    return date.toLocaleString();
  }

  private isImage(): boolean {
    return this.contentType.startsWith('image/');
  }

  private isText(): boolean {
    return (
      this.contentType.startsWith('text/') ||
      this.contentType === 'application/json' ||
      this.contentType === 'application/xml' ||
      this.contentType === 'application/javascript'
    );
  }

  private getTextContent(): string {
    try {
      return atob(this.content);
    } catch {
      return 'Unable to decode content';
    }
  }

  private async handleDownload() {
    try {
      const blob = new Blob([Uint8Array.from(atob(this.content), (c) => c.charCodeAt(0))], {
        type: this.contentType,
      });
      const url = URL.createObjectURL(blob);
      const a = document.createElement('a');
      a.href = url;
      a.download = this.getFileName(this.objectKey);
      document.body.appendChild(a);
      a.click();
      document.body.removeChild(a);
      URL.revokeObjectURL(url);
    } catch (err) {
      console.error('Error downloading:', err);
    }
  }

  private async handleDelete() {
    if (!confirm(`Delete "${this.getFileName(this.objectKey)}"?`)) return;

    try {
      await apiService.deleteObject(this.bucketName, this.objectKey);
      this.dispatchEvent(
        new CustomEvent('object-deleted', {
          detail: { key: this.objectKey },
          bubbles: true,
          composed: true,
        })
      );
    } catch (err) {
      console.error('Error deleting object:', err);
    }
  }

  render() {
    if (!this.objectKey) {
      return html`
        <div class="preview-container">
          <div class="empty-state">
            <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2">
              <path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z" />
              <polyline points="14 2 14 8 20 8" />
            </svg>
            <p>Select a file to preview</p>
          </div>
        </div>
      `;
    }

    if (this.loading) {
      return html`
        <div class="preview-container">
          <div class="loading-state">Loading...</div>
        </div>
      `;
    }

    if (this.error) {
      return html`
        <div class="preview-container">
          <div class="error-state">${this.error}</div>
        </div>
      `;
    }

    return html`
      <div class="preview-container">
        <div class="preview-header">
          <div class="preview-title">${this.getFileName(this.objectKey)}</div>
          <div class="preview-meta">
            <span class="meta-item">${this.contentType}</span>
            <span class="meta-item">${this.formatSize(this.size)}</span>
            <span class="meta-item">${this.formatDate(this.lastModified)}</span>
          </div>
        </div>

        <div class="preview-content">
          ${this.isImage()
            ? html`<img class="preview-image" src="data:${this.contentType};base64,${this.content}" />`
            : this.isText()
              ? html`<pre class="preview-text">${this.getTextContent()}</pre>`
              : html`
                  <div class="binary-preview">
                    <p>Binary file preview not available</p>
                    <p>Download to view</p>
                  </div>
                `}
        </div>

        <div class="preview-actions">
          <button class="action-btn" @click=${this.handleDownload}>Download</button>
          <button class="action-btn danger" @click=${this.handleDelete}>Delete</button>
        </div>
      </div>
    `;
  }
}