/**
 * @file sdig-contract-attachments.ts
 * @description Contract attachments and prior contracts manager
 */

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

import * as plugins from '../../plugins.js';

declare global {
  interface HTMLElementTagNameMap {
    'sdig-contract-attachments': SdigContractAttachments;
  }
}

// Attachment interface
interface IAttachment {
  id: string;
  name: string;
  type: 'document' | 'image' | 'spreadsheet' | 'pdf' | 'other';
  mimeType: string;
  size: number;
  uploadedAt: number;
  uploadedBy: string;
  description?: string;
  url?: string;
}

// File type configuration
const FILE_TYPES = {
  document: { icon: 'lucide:FileText', color: '#3b82f6', label: 'Document' },
  image: { icon: 'lucide:Image', color: '#10b981', label: 'Image' },
  spreadsheet: { icon: 'lucide:Sheet', color: '#22c55e', label: 'Spreadsheet' },
  pdf: { icon: 'lucide:FileType', color: '#ef4444', label: 'PDF' },
  other: { icon: 'lucide:File', color: '#6b7280', label: 'File' },
};

@customElement('sdig-contract-attachments')
export class SdigContractAttachments extends DeesElement {
  // ============================================================================
  // STATIC
  // ============================================================================

  public static demo = () => html`
    <sdig-contract-attachments
      .contract=${plugins.sdDemodata.demoContract}
    ></sdig-contract-attachments>
  `;

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

      .attachments-container {
        display: flex;
        flex-direction: column;
        gap: 24px;
      }

      /* Section card */
      .section-card {
        background: ${cssManager.bdTheme('#ffffff', '#0a0a0a')};
        border: 1px solid ${cssManager.bdTheme('#e5e5e5', '#27272a')};
        border-radius: 12px;
        overflow: hidden;
      }

      .section-header {
        display: flex;
        align-items: center;
        justify-content: space-between;
        padding: 16px 20px;
        background: ${cssManager.bdTheme('#f9fafb', '#111111')};
        border-bottom: 1px solid ${cssManager.bdTheme('#e5e5e5', '#27272a')};
      }

      .section-title {
        display: flex;
        align-items: center;
        gap: 10px;
        font-size: 15px;
        font-weight: 600;
        color: ${cssManager.bdTheme('#111111', '#fafafa')};
      }

      .section-title dees-icon {
        font-size: 18px;
        color: ${cssManager.bdTheme('#6b7280', '#9ca3af')};
      }

      .section-count {
        font-size: 13px;
        color: ${cssManager.bdTheme('#6b7280', '#9ca3af')};
      }

      .section-content {
        padding: 20px;
      }

      /* Upload zone */
      .upload-zone {
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        padding: 40px 20px;
        border: 2px dashed ${cssManager.bdTheme('#d1d5db', '#3f3f46')};
        border-radius: 12px;
        background: ${cssManager.bdTheme('#f9fafb', '#111111')};
        cursor: pointer;
        transition: all 0.15s ease;
      }

      .upload-zone:hover {
        border-color: ${cssManager.bdTheme('#9ca3af', '#52525b')};
        background: ${cssManager.bdTheme('#f3f4f6', '#18181b')};
      }

      .upload-zone.dragging {
        border-color: ${cssManager.bdTheme('#3b82f6', '#60a5fa')};
        background: ${cssManager.bdTheme('#eff6ff', '#172554')};
      }

      .upload-zone-icon {
        width: 64px;
        height: 64px;
        border-radius: 16px;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 28px;
        background: ${cssManager.bdTheme('#e5e7eb', '#27272a')};
        color: ${cssManager.bdTheme('#6b7280', '#9ca3af')};
        margin-bottom: 16px;
      }

      .upload-zone-title {
        font-size: 16px;
        font-weight: 600;
        color: ${cssManager.bdTheme('#111111', '#fafafa')};
        margin-bottom: 8px;
      }

      .upload-zone-subtitle {
        font-size: 14px;
        color: ${cssManager.bdTheme('#6b7280', '#9ca3af')};
        margin-bottom: 16px;
      }

      .upload-zone-hint {
        font-size: 12px;
        color: ${cssManager.bdTheme('#9ca3af', '#6b7280')};
      }

      /* Attachments list */
      .attachments-list {
        display: flex;
        flex-direction: column;
        gap: 12px;
      }

      .attachment-item {
        display: flex;
        align-items: center;
        gap: 14px;
        padding: 14px 16px;
        background: ${cssManager.bdTheme('#f9fafb', '#111111')};
        border: 1px solid ${cssManager.bdTheme('#e5e5e5', '#27272a')};
        border-radius: 10px;
        transition: all 0.15s ease;
      }

      .attachment-item:hover {
        border-color: ${cssManager.bdTheme('#d1d5db', '#3f3f46')};
      }

      .attachment-icon {
        width: 44px;
        height: 44px;
        border-radius: 10px;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 20px;
        flex-shrink: 0;
      }

      .attachment-info {
        flex: 1;
        min-width: 0;
      }

      .attachment-name {
        font-size: 14px;
        font-weight: 600;
        color: ${cssManager.bdTheme('#111111', '#fafafa')};
        margin-bottom: 4px;
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
      }

      .attachment-meta {
        display: flex;
        flex-wrap: wrap;
        gap: 12px;
        font-size: 12px;
        color: ${cssManager.bdTheme('#6b7280', '#9ca3af')};
      }

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

      .attachment-actions {
        display: flex;
        gap: 4px;
        flex-shrink: 0;
      }

      /* Prior contracts */
      .prior-contracts-list {
        display: flex;
        flex-direction: column;
        gap: 12px;
      }

      .prior-contract-item {
        display: flex;
        align-items: center;
        gap: 14px;
        padding: 16px;
        background: ${cssManager.bdTheme('#f9fafb', '#111111')};
        border: 1px solid ${cssManager.bdTheme('#e5e5e5', '#27272a')};
        border-radius: 10px;
        cursor: pointer;
        transition: all 0.15s ease;
      }

      .prior-contract-item:hover {
        border-color: ${cssManager.bdTheme('#d1d5db', '#3f3f46')};
        background: ${cssManager.bdTheme('#f3f4f6', '#18181b')};
      }

      .prior-contract-icon {
        width: 48px;
        height: 48px;
        border-radius: 10px;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 22px;
        background: ${cssManager.bdTheme('#dbeafe', '#1e3a5f')};
        color: ${cssManager.bdTheme('#3b82f6', '#60a5fa')};
        flex-shrink: 0;
      }

      .prior-contract-info {
        flex: 1;
        min-width: 0;
      }

      .prior-contract-title {
        font-size: 15px;
        font-weight: 600;
        color: ${cssManager.bdTheme('#111111', '#fafafa')};
        margin-bottom: 4px;
      }

      .prior-contract-context {
        font-size: 13px;
        color: ${cssManager.bdTheme('#6b7280', '#9ca3af')};
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
      }

      .prior-contract-actions {
        display: flex;
        gap: 8px;
        flex-shrink: 0;
      }

      /* Empty state */
      .empty-state {
        display: flex;
        flex-direction: column;
        align-items: center;
        padding: 40px 20px;
        text-align: center;
        color: ${cssManager.bdTheme('#6b7280', '#9ca3af')};
      }

      .empty-state dees-icon {
        font-size: 48px;
        margin-bottom: 16px;
        opacity: 0.5;
      }

      .empty-state h4 {
        margin: 0 0 8px;
        font-size: 16px;
        font-weight: 600;
        color: ${cssManager.bdTheme('#374151', '#d1d5db')};
      }

      .empty-state p {
        margin: 0;
        font-size: 14px;
      }

      /* Storage summary */
      .storage-summary {
        display: flex;
        align-items: center;
        gap: 16px;
        padding: 16px;
        background: ${cssManager.bdTheme('#f9fafb', '#111111')};
        border: 1px solid ${cssManager.bdTheme('#e5e5e5', '#27272a')};
        border-radius: 10px;
        margin-bottom: 20px;
      }

      .storage-info {
        flex: 1;
      }

      .storage-label {
        font-size: 13px;
        color: ${cssManager.bdTheme('#6b7280', '#9ca3af')};
        margin-bottom: 6px;
      }

      .storage-bar {
        height: 6px;
        background: ${cssManager.bdTheme('#e5e7eb', '#27272a')};
        border-radius: 3px;
        overflow: hidden;
      }

      .storage-fill {
        height: 100%;
        background: ${cssManager.bdTheme('#3b82f6', '#60a5fa')};
        transition: width 0.3s ease;
      }

      .storage-text {
        font-size: 14px;
        font-weight: 600;
        color: ${cssManager.bdTheme('#111111', '#fafafa')};
        white-space: nowrap;
      }

      /* Buttons */
      .btn {
        display: inline-flex;
        align-items: center;
        gap: 6px;
        padding: 8px 14px;
        font-size: 13px;
        font-weight: 500;
        border-radius: 6px;
        border: none;
        cursor: pointer;
        transition: all 0.15s ease;
      }

      .btn-sm {
        padding: 6px 10px;
        font-size: 12px;
      }

      .btn-primary {
        background: ${cssManager.bdTheme('#111111', '#fafafa')};
        color: ${cssManager.bdTheme('#ffffff', '#09090b')};
      }

      .btn-primary:hover {
        background: ${cssManager.bdTheme('#333333', '#e5e5e5')};
      }

      .btn-secondary {
        background: ${cssManager.bdTheme('#f3f4f6', '#27272a')};
        color: ${cssManager.bdTheme('#374151', '#d1d5db')};
      }

      .btn-secondary:hover {
        background: ${cssManager.bdTheme('#e5e7eb', '#3f3f46')};
      }

      .btn-ghost {
        background: transparent;
        color: ${cssManager.bdTheme('#6b7280', '#9ca3af')};
        padding: 6px;
      }

      .btn-ghost:hover {
        background: ${cssManager.bdTheme('#f3f4f6', '#27272a')};
        color: ${cssManager.bdTheme('#111111', '#fafafa')};
      }

      .btn-danger {
        color: ${cssManager.bdTheme('#dc2626', '#f87171')};
      }

      .btn-danger:hover {
        background: ${cssManager.bdTheme('#fef2f2', '#450a0a')};
      }

      /* Type badge */
      .type-badge {
        display: inline-flex;
        align-items: center;
        gap: 4px;
        padding: 2px 8px;
        border-radius: 4px;
        font-size: 11px;
        font-weight: 500;
        background: ${cssManager.bdTheme('#e5e7eb', '#27272a')};
        color: ${cssManager.bdTheme('#374151', '#d1d5db')};
      }
    `,
  ];

  // ============================================================================
  // PROPERTIES
  // ============================================================================

  @property({ type: Object })
  public accessor contract: plugins.sdInterfaces.IPortableContract | null = null;

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

  // ============================================================================
  // STATE
  // ============================================================================

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

  // Demo attachments data
  @state()
  private accessor attachments: IAttachment[] = [
    {
      id: '1',
      name: 'Employment_Terms_v2.pdf',
      type: 'pdf',
      mimeType: 'application/pdf',
      size: 245760,
      uploadedAt: Date.now() - 86400000 * 3,
      uploadedBy: 'employer',
      description: 'Original employment terms document',
    },
    {
      id: '2',
      name: 'ID_Verification.png',
      type: 'image',
      mimeType: 'image/png',
      size: 1024000,
      uploadedAt: Date.now() - 86400000,
      uploadedBy: 'employee',
    },
    {
      id: '3',
      name: 'Tax_Information.xlsx',
      type: 'spreadsheet',
      mimeType: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
      size: 52480,
      uploadedAt: Date.now() - 86400000 * 2,
      uploadedBy: 'employer',
    },
  ];

  // ============================================================================
  // EVENT HANDLERS
  // ============================================================================

  private handleFieldChange(path: string, value: unknown) {
    this.dispatchEvent(
      new CustomEvent('field-change', {
        detail: { path, value },
        bubbles: true,
        composed: true,
      })
    );
  }

  private handleDragEnter(e: DragEvent) {
    e.preventDefault();
    e.stopPropagation();
    this.isDragging = true;
  }

  private handleDragLeave(e: DragEvent) {
    e.preventDefault();
    e.stopPropagation();
    this.isDragging = false;
  }

  private handleDragOver(e: DragEvent) {
    e.preventDefault();
    e.stopPropagation();
  }

  private handleDrop(e: DragEvent) {
    e.preventDefault();
    e.stopPropagation();
    this.isDragging = false;

    const files = e.dataTransfer?.files;
    if (files && files.length > 0) {
      this.handleFiles(files);
    }
  }

  private handleFileSelect() {
    const input = document.createElement('input');
    input.type = 'file';
    input.multiple = true;
    input.onchange = () => {
      if (input.files && input.files.length > 0) {
        this.handleFiles(input.files);
      }
    };
    input.click();
  }

  private handleFiles(files: FileList) {
    // Demo: just add to list
    Array.from(files).forEach((file) => {
      const newAttachment: IAttachment = {
        id: `att-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
        name: file.name,
        type: this.getFileType(file.type),
        mimeType: file.type,
        size: file.size,
        uploadedAt: Date.now(),
        uploadedBy: 'user',
      };
      this.attachments = [...this.attachments, newAttachment];
    });
  }

  private handleDeleteAttachment(attachmentId: string) {
    this.attachments = this.attachments.filter((a) => a.id !== attachmentId);
  }

  private handleAddPriorContract() {
    // TODO: Open prior contract picker modal
  }

  private handleRemovePriorContract(index: number) {
    if (!this.contract) return;
    const updatedPriorContracts = [...this.contract.priorContracts];
    updatedPriorContracts.splice(index, 1);
    this.handleFieldChange('priorContracts', updatedPriorContracts);
  }

  // ============================================================================
  // HELPERS
  // ============================================================================

  private getFileType(mimeType: string): IAttachment['type'] {
    if (mimeType.includes('pdf')) return 'pdf';
    if (mimeType.includes('image')) return 'image';
    if (mimeType.includes('spreadsheet') || mimeType.includes('excel')) return 'spreadsheet';
    if (mimeType.includes('document') || mimeType.includes('word')) return 'document';
    return 'other';
  }

  private getFileTypeConfig(type: IAttachment['type']) {
    return FILE_TYPES[type] || FILE_TYPES.other;
  }

  private formatFileSize(bytes: number): string {
    if (bytes === 0) return '0 B';
    const k = 1024;
    const sizes = ['B', 'KB', 'MB', 'GB'];
    const i = Math.floor(Math.log(bytes) / Math.log(k));
    return parseFloat((bytes / Math.pow(k, i)).toFixed(1)) + ' ' + sizes[i];
  }

  private formatDate(timestamp: number): string {
    return new Date(timestamp).toLocaleDateString('en-US', {
      month: 'short',
      day: 'numeric',
      year: 'numeric',
    });
  }

  private getTotalSize(): number {
    return this.attachments.reduce((sum, a) => sum + a.size, 0);
  }

  private getPartyName(roleId: string): string {
    const role = this.contract?.availableRoles.find((r) => r.id === roleId);
    return role?.name || roleId;
  }

  // ============================================================================
  // RENDER
  // ============================================================================

  public render(): TemplateResult {
    if (!this.contract) {
      return html`<div>No contract loaded</div>`;
    }

    const totalSize = this.getTotalSize();
    const maxSize = 50 * 1024 * 1024; // 50MB demo limit
    const usagePercent = Math.min((totalSize / maxSize) * 100, 100);

    return html`
      <div class="attachments-container">
        <!-- Attachments Section -->
        <div class="section-card">
          <div class="section-header">
            <div class="section-title">
              <dees-icon .icon=${'lucide:Paperclip'}></dees-icon>
              Attachments
            </div>
            <span class="section-count">${this.attachments.length} files</span>
          </div>
          <div class="section-content">
            <!-- Storage summary -->
            <div class="storage-summary">
              <div class="storage-info">
                <div class="storage-label">Storage used</div>
                <div class="storage-bar">
                  <div class="storage-fill" style="width: ${usagePercent}%"></div>
                </div>
              </div>
              <div class="storage-text">
                ${this.formatFileSize(totalSize)} / ${this.formatFileSize(maxSize)}
              </div>
            </div>

            <!-- Upload zone -->
            ${!this.readonly
              ? html`
                  <div
                    class="upload-zone ${this.isDragging ? 'dragging' : ''}"
                    @dragenter=${this.handleDragEnter}
                    @dragleave=${this.handleDragLeave}
                    @dragover=${this.handleDragOver}
                    @drop=${this.handleDrop}
                    @click=${this.handleFileSelect}
                  >
                    <div class="upload-zone-icon">
                      <dees-icon .icon=${'lucide:UploadCloud'}></dees-icon>
                    </div>
                    <div class="upload-zone-title">Drop files here or click to upload</div>
                    <div class="upload-zone-subtitle">Add supporting documents, images, or spreadsheets</div>
                    <div class="upload-zone-hint">PDF, DOCX, XLSX, PNG, JPG up to 10MB each</div>
                  </div>
                `
              : ''}

            <!-- Attachments list -->
            ${this.attachments.length > 0
              ? html`
                  <div class="attachments-list" style="margin-top: 20px;">
                    ${this.attachments.map((attachment) => this.renderAttachmentItem(attachment))}
                  </div>
                `
              : html`
                  <div class="empty-state" style="margin-top: 20px;">
                    <dees-icon .icon=${'lucide:FileX'}></dees-icon>
                    <h4>No Attachments</h4>
                    <p>Upload files to attach them to this contract</p>
                  </div>
                `}
          </div>
        </div>

        <!-- Prior Contracts Section -->
        <div class="section-card">
          <div class="section-header">
            <div class="section-title">
              <dees-icon .icon=${'lucide:Files'}></dees-icon>
              Prior Contracts
            </div>
            ${!this.readonly
              ? html`
                  <button class="btn btn-secondary" @click=${this.handleAddPriorContract}>
                    <dees-icon .icon=${'lucide:Plus'}></dees-icon>
                    Link Contract
                  </button>
                `
              : ''}
          </div>
          <div class="section-content">
            ${this.contract.priorContracts.length > 0
              ? html`
                  <div class="prior-contracts-list">
                    ${this.contract.priorContracts.map((priorContract, index) =>
                      this.renderPriorContractItem(priorContract, index)
                    )}
                  </div>
                `
              : html`
                  <div class="empty-state">
                    <dees-icon .icon=${'lucide:Link'}></dees-icon>
                    <h4>No Prior Contracts</h4>
                    <p>Link related or predecessor contracts here</p>
                  </div>
                `}
          </div>
        </div>
      </div>
    `;
  }

  private renderAttachmentItem(attachment: IAttachment): TemplateResult {
    const typeConfig = this.getFileTypeConfig(attachment.type);

    return html`
      <div class="attachment-item">
        <div class="attachment-icon" style="background: ${typeConfig.color}20; color: ${typeConfig.color}">
          <dees-icon .icon=${typeConfig.icon}></dees-icon>
        </div>
        <div class="attachment-info">
          <div class="attachment-name">${attachment.name}</div>
          <div class="attachment-meta">
            <span class="type-badge">${typeConfig.label}</span>
            <span class="attachment-meta-item">
              ${this.formatFileSize(attachment.size)}
            </span>
            <span class="attachment-meta-item">
              <dees-icon .icon=${'lucide:Calendar'}></dees-icon>
              ${this.formatDate(attachment.uploadedAt)}
            </span>
            <span class="attachment-meta-item">
              <dees-icon .icon=${'lucide:User'}></dees-icon>
              ${this.getPartyName(attachment.uploadedBy)}
            </span>
          </div>
        </div>
        <div class="attachment-actions">
          <button class="btn btn-ghost" title="Download">
            <dees-icon .icon=${'lucide:Download'}></dees-icon>
          </button>
          <button class="btn btn-ghost" title="Preview">
            <dees-icon .icon=${'lucide:Eye'}></dees-icon>
          </button>
          ${!this.readonly
            ? html`
                <button
                  class="btn btn-ghost btn-danger"
                  title="Delete"
                  @click=${() => this.handleDeleteAttachment(attachment.id)}
                >
                  <dees-icon .icon=${'lucide:Trash2'}></dees-icon>
                </button>
              `
            : ''}
        </div>
      </div>
    `;
  }

  private renderPriorContractItem(priorContract: plugins.sdInterfaces.IPortableContract, index: number): TemplateResult {
    return html`
      <div class="prior-contract-item">
        <div class="prior-contract-icon">
          <dees-icon .icon=${'lucide:FileText'}></dees-icon>
        </div>
        <div class="prior-contract-info">
          <div class="prior-contract-title">${priorContract.title}</div>
          <div class="prior-contract-context">${priorContract.context || 'No description'}</div>
        </div>
        <div class="prior-contract-actions">
          <button class="btn btn-secondary btn-sm">
            <dees-icon .icon=${'lucide:ExternalLink'}></dees-icon>
            View
          </button>
          ${!this.readonly
            ? html`
                <button
                  class="btn btn-ghost btn-danger"
                  @click=${() => this.handleRemovePriorContract(index)}
                >
                  <dees-icon .icon=${'lucide:Unlink'}></dees-icon>
                </button>
              `
            : ''}
        </div>
      </div>
    `;
  }
}