import { Component, inject, signal, OnInit } from '@angular/core';
import { CommonModule } from '@angular/common';
import { FormsModule } from '@angular/forms';
import { debounceTime, distinctUntilChanged, Subject, switchMap, of } from 'rxjs';
import { CodesService, CodeEntry, PagedResult } from '../../core/services/codes.service';

type Tab = 'all' | 'icd10' | 'cpt';

@Component({
  selector: 'app-codes-search',
  standalone: true,
  imports: [CommonModule, FormsModule],
  template: `
    <div class="codes-page">
      <header class="page-header">
        <div>
          <h1>Code Search</h1>
          <p>Search ICD-10 diagnostic codes and CPT procedure codes</p>
        </div>
      </header>

      <!-- Search bar -->
      <div class="search-section">
        <div class="search-box">
          <svg class="search-icon" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2">
            <circle cx="11" cy="11" r="8"/><path d="m21 21-4.35-4.35"/>
          </svg>
          <input
            class="search-input"
            type="text"
            [(ngModel)]="query"
            (ngModelChange)="onSearch($event)"
            placeholder="Search by code or description (e.g. J18.9, pneumonia, 99213...)"
          />
          @if (query) {
            <button class="clear-btn" (click)="clear()">✕</button>
          }
        </div>

        <div class="tabs">
          @for (tab of tabs; track tab.id) {
            <button class="tab" [class.active]="activeTab() === tab.id" (click)="switchTab(tab.id)">
              {{ tab.label }}
              @if (tab.id === 'icd10' && icd10Results()?.total) {
                <span class="badge">{{ icd10Results()!.total }}</span>
              }
              @if (tab.id === 'cpt' && cptResults()?.total) {
                <span class="badge">{{ cptResults()!.total }}</span>
              }
            </button>
          }
        </div>
      </div>

      <!-- Loading -->
      @if (loading()) {
        <div class="loading-state">
          <div class="spinner"></div>
          <span>Searching codes...</span>
        </div>
      }

      <!-- Global results (all tab) -->
      @if (!loading() && activeTab() === 'all' && query) {
        <div class="results-split">
          <div class="results-col">
            <div class="col-header">
              <span class="col-badge icd10">ICD-10</span>
              <span class="col-count">{{ globalResults()?.icd10?.length || 0 }} results</span>
            </div>
            @for (code of globalResults()?.icd10; track code._id) {
              <div class="code-card" (click)="selectCode(code)">
                <div class="code-tag icd10">{{ code.code }}</div>
                <div class="code-body">
                  <p class="code-desc">{{ code.description }}</p>
                  @if (code.category) { <p class="code-cat">{{ code.category }}</p> }
                </div>
                <div class="code-badge" [class.billable]="code.billable">
                  {{ code.billable ? 'Billable' : 'Non-billable' }}
                </div>
              </div>
            }
            @if (!globalResults()?.icd10?.length) {
              <div class="empty-col">No ICD-10 results</div>
            }
          </div>

          <div class="results-col">
            <div class="col-header">
              <span class="col-badge cpt">CPT</span>
              <span class="col-count">{{ globalResults()?.cpt?.length || 0 }} results</span>
            </div>
            @for (code of globalResults()?.cpt; track code._id) {
              <div class="code-card" (click)="selectCode(code)">
                <div class="code-tag cpt">{{ code.code }}</div>
                <div class="code-body">
                  <p class="code-desc">{{ code.description }}</p>
                  @if (code.category) { <p class="code-cat">{{ code.category }}</p> }
                </div>
                <div class="code-badge" [class.billable]="code.billable">
                  {{ code.billable ? 'Billable' : 'Non-billable' }}
                </div>
              </div>
            }
            @if (!globalResults()?.cpt?.length) {
              <div class="empty-col">No CPT results</div>
            }
          </div>
        </div>
      }

      <!-- ICD-10 tab -->
      @if (!loading() && activeTab() === 'icd10') {
        <div class="results-list">
          @for (code of icd10Results()?.data; track code._id) {
            <div class="code-card" (click)="selectCode(code)">
              <div class="code-tag icd10">{{ code.code }}</div>
              <div class="code-body">
                <p class="code-desc">{{ code.description }}</p>
                @if (code.category) { <p class="code-cat">{{ code.category }}</p> }
              </div>
              <div class="code-badge" [class.billable]="code.billable">
                {{ code.billable ? 'Billable' : 'Non-billable' }}
              </div>
            </div>
          }
          @if (icd10Results()?.pages && icd10Results()!.pages > 1) {
            <div class="pagination">
              <button [disabled]="icd10Page() === 1" (click)="changePage('icd10', -1)">← Prev</button>
              <span>Page {{ icd10Page() }} of {{ icd10Results()?.pages }}</span>
              <button [disabled]="icd10Page() === icd10Results()?.pages" (click)="changePage('icd10', 1)">Next →</button>
            </div>
          }
        </div>
      }

      <!-- CPT tab -->
      @if (!loading() && activeTab() === 'cpt') {
        <div class="results-list">
          @for (code of cptResults()?.data; track code._id) {
            <div class="code-card" (click)="selectCode(code)">
              <div class="code-tag cpt">{{ code.code }}</div>
              <div class="code-body">
                <p class="code-desc">{{ code.description }}</p>
                @if (code.category) { <p class="code-cat">{{ code.category }}</p> }
              </div>
              <div class="code-badge" [class.billable]="code.billable">
                {{ code.billable ? 'Billable' : 'Non-billable' }}
              </div>
            </div>
          }
          @if (cptResults()?.pages && cptResults()!.pages > 1) {
            <div class="pagination">
              <button [disabled]="cptPage() === 1" (click)="changePage('cpt', -1)">← Prev</button>
              <span>Page {{ cptPage() }} of {{ cptResults()?.pages }}</span>
              <button [disabled]="cptPage() === cptResults()?.pages" (click)="changePage('cpt', 1)">Next →</button>
            </div>
          }
        </div>
      }

      <!-- Empty state -->
      @if (!loading() && !query) {
        <div class="empty-state">
          <svg viewBox="0 0 64 64" fill="none">
            <circle cx="28" cy="28" r="20" stroke="#cbd5e1" stroke-width="3"/>
            <path d="m44 44 12 12" stroke="#cbd5e1" stroke-width="3" stroke-linecap="round"/>
            <path d="M20 28h16M28 20v16" stroke="#94a3b8" stroke-width="2.5" stroke-linecap="round"/>
          </svg>
          <h3>Start searching</h3>
          <p>Enter a code like <strong>J18.9</strong> or keyword like <strong>pneumonia</strong></p>
        </div>
      }

      <!-- Code detail modal -->
      @if (selectedCode()) {
        <div class="modal-overlay" (click)="selectedCode.set(null)">
          <div class="modal" (click)="$event.stopPropagation()">
            <div class="modal-header">
              <div class="code-tag" [class.icd10]="selectedCode()!.type === 'ICD-10'" [class.cpt]="selectedCode()!.type === 'CPT' || !selectedCode()!.type">
                {{ selectedCode()?.code }}
              </div>
              <button class="modal-close" (click)="selectedCode.set(null)">✕</button>
            </div>
            <div class="modal-body">
              <h2>{{ selectedCode()?.description }}</h2>
              @if (selectedCode()?.category) {
                <div class="detail-row"><span>Category</span><strong>{{ selectedCode()?.category }}</strong></div>
              }
              <div class="detail-row">
                <span>Billable</span>
                <strong [style.color]="selectedCode()?.billable ? '#16a34a' : '#dc2626'">
                  {{ selectedCode()?.billable ? 'Yes' : 'No' }}
                </strong>
              </div>
              <div class="detail-row"><span>Type</span><strong>{{ selectedCode()?.type || 'ICD-10' }}</strong></div>
            </div>
            <div class="modal-footer">
              <button class="btn-copy" (click)="copyCode(selectedCode()!.code)">
                {{ copied() ? '✓ Copied!' : 'Copy code' }}
              </button>
            </div>
          </div>
        </div>
      }
    </div>
  `,
  styles: [`
    .codes-page { padding:2rem; max-width:1200px; font-family:'Inter',system-ui,sans-serif; }
    .page-header { margin-bottom:1.5rem; }
    .page-header h1 { font-size:1.75rem; font-weight:700; color:#0f172a; margin:0 0 0.25rem; }
    .page-header p { color:#64748b; margin:0; }

    .search-section { margin-bottom:1.5rem; }
    .search-box { position:relative; margin-bottom:1rem; }
    .search-icon { position:absolute; left:1rem; top:50%; transform:translateY(-50%); width:20px; height:20px; color:#94a3b8; }
    .search-input {
      width:100%; padding:0.9rem 3rem; border:1px solid #e2e8f0; border-radius:12px;
      font-size:1rem; background:white; box-sizing:border-box; outline:none;
      transition:border-color 0.15s, box-shadow 0.15s; box-shadow:0 1px 3px rgba(0,0,0,0.06);
    }
    .search-input:focus { border-color:#0EA5E9; box-shadow:0 0 0 3px rgba(14,165,233,0.15); }
    .clear-btn { position:absolute; right:1rem; top:50%; transform:translateY(-50%); background:none; border:none; cursor:pointer; color:#94a3b8; font-size:1rem; }

    .tabs { display:flex; gap:0.5rem; }
    .tab {
      padding:0.5rem 1.25rem; border:1px solid #e2e8f0; border-radius:8px; background:white;
      font-size:0.875rem; font-weight:500; color:#64748b; cursor:pointer; display:flex; align-items:center; gap:0.5rem;
      transition:all 0.15s;
    }
    .tab.active { background:#0EA5E9; color:white; border-color:#0EA5E9; }
    .badge { background:rgba(255,255,255,0.3); border-radius:999px; padding:0.1rem 0.5rem; font-size:0.75rem; }
    .tab:not(.active) .badge { background:#e0f2fe; color:#0369a1; }

    .loading-state { display:flex; align-items:center; gap:0.75rem; padding:3rem; color:#64748b; justify-content:center; }
    .spinner { width:24px; height:24px; border:2px solid #e2e8f0; border-top-color:#0EA5E9; border-radius:50%; animation:spin 0.6s linear infinite; }
    @keyframes spin { to { transform:rotate(360deg); } }

    .results-split { display:grid; grid-template-columns:1fr 1fr; gap:1.5rem; }
    .results-col { display:flex; flex-direction:column; gap:0.5rem; }
    .col-header { display:flex; align-items:center; gap:0.75rem; margin-bottom:0.5rem; }
    .col-count { font-size:0.8rem; color:#94a3b8; }
    .col-badge { padding:0.25rem 0.75rem; border-radius:999px; font-size:0.75rem; font-weight:700; }
    .col-badge.icd10 { background:#eff6ff; color:#1d4ed8; }
    .col-badge.cpt { background:#f0fdf4; color:#15803d; }
    .empty-col { color:#94a3b8; font-size:0.875rem; padding:1rem; text-align:center; background:white; border-radius:8px; border:1px dashed #e2e8f0; }

    .results-list { display:flex; flex-direction:column; gap:0.5rem; }
    .code-card {
      background:white; border:1px solid #e2e8f0; border-radius:10px; padding:1rem;
      display:flex; align-items:center; gap:1rem; cursor:pointer; transition:border-color 0.15s, box-shadow 0.15s;
    }
    .code-card:hover { border-color:#0EA5E9; box-shadow:0 0 0 3px rgba(14,165,233,0.08); }
    .code-tag {
      padding:0.35rem 0.75rem; border-radius:6px; font-size:0.85rem; font-weight:700;
      white-space:nowrap; font-family:'JetBrains Mono',monospace;
    }
    .code-tag.icd10 { background:#eff6ff; color:#1d4ed8; }
    .code-tag.cpt { background:#f0fdf4; color:#15803d; }
    .code-body { flex:1; min-width:0; }
    .code-desc { margin:0; font-size:0.9rem; color:#1e293b; font-weight:500; }
    .code-cat { margin:0.2rem 0 0; font-size:0.775rem; color:#94a3b8; }
    .code-badge { padding:0.2rem 0.6rem; border-radius:999px; font-size:0.7rem; font-weight:600; background:#f1f5f9; color:#64748b; white-space:nowrap; }
    .code-badge.billable { background:#f0fdf4; color:#16a34a; }

    .pagination { display:flex; align-items:center; justify-content:center; gap:1rem; padding:1rem; }
    .pagination button { padding:0.5rem 1rem; border:1px solid #e2e8f0; border-radius:6px; background:white; cursor:pointer; font-size:0.875rem; }
    .pagination button:disabled { opacity:0.4; cursor:not-allowed; }
    .pagination span { color:#64748b; font-size:0.875rem; }

    .empty-state { display:flex; flex-direction:column; align-items:center; padding:5rem 2rem; color:#94a3b8; }
    .empty-state svg { width:80px; height:80px; margin-bottom:1.5rem; }
    .empty-state h3 { font-size:1.1rem; color:#475569; margin:0 0 0.5rem; }
    .empty-state p { margin:0; font-size:0.9rem; text-align:center; }
    .empty-state strong { color:#475569; }

    .modal-overlay { position:fixed; inset:0; background:rgba(15,23,42,0.5); display:flex; align-items:center; justify-content:center; z-index:100; }
    .modal { background:white; border-radius:16px; width:100%; max-width:480px; box-shadow:0 25px 50px rgba(0,0,0,0.25); overflow:hidden; }
    .modal-header { display:flex; align-items:center; justify-content:space-between; padding:1.25rem 1.5rem; border-bottom:1px solid #f1f5f9; }
    .modal-close { background:none; border:none; cursor:pointer; color:#94a3b8; font-size:1.2rem; }
    .modal-body { padding:1.5rem; }
    .modal-body h2 { font-size:1.1rem; font-weight:600; color:#0f172a; margin:0 0 1.25rem; }
    .detail-row { display:flex; justify-content:space-between; padding:0.6rem 0; border-bottom:1px solid #f8fafc; font-size:0.875rem; }
    .detail-row span { color:#64748b; }
    .modal-footer { padding:1rem 1.5rem; border-top:1px solid #f1f5f9; display:flex; justify-content:flex-end; }
    .btn-copy { padding:0.6rem 1.5rem; background:#0EA5E9; color:white; border:none; border-radius:8px; font-weight:600; cursor:pointer; font-size:0.9rem; }
    .btn-copy:hover { background:#0284c7; }

    @media (max-width: 768px) { .results-split { grid-template-columns:1fr; } }
  `],
})
export class CodesSearchComponent implements OnInit {
  private codesService = inject(CodesService);
  private search$ = new Subject<string>();

  query = '';
  activeTab = signal<Tab>('all');
  loading = signal(false);
  globalResults = signal<any>(null);
  icd10Results = signal<PagedResult<CodeEntry> | null>(null);
  cptResults = signal<PagedResult<CodeEntry> | null>(null);
  icd10Page = signal(1);
  cptPage = signal(1);
  selectedCode = signal<CodeEntry | null>(null);
  copied = signal(false);

  tabs = [
    { id: 'all' as Tab, label: 'All' },
    { id: 'icd10' as Tab, label: 'ICD-10' },
    { id: 'cpt' as Tab, label: 'CPT' },
  ];

  ngOnInit() {
    this.search$.pipe(
      debounceTime(300),
      distinctUntilChanged(),
      switchMap(q => {
        if (!q.trim()) return of(null);
        this.loading.set(true);
        if (this.activeTab() === 'all') return this.codesService.globalSearch(q);
        if (this.activeTab() === 'icd10') return this.codesService.searchICD10(q, this.icd10Page());
        return this.codesService.searchCPT(q, this.cptPage());
      }),
    ).subscribe(res => {
      this.loading.set(false);
      if (!res) return;
      if (this.activeTab() === 'all') this.globalResults.set(res);
      else if (this.activeTab() === 'icd10') this.icd10Results.set(res as any);
      else this.cptResults.set(res as any);
    });

    // Load all ICD-10 and CPT on startup for browsing
    this.codesService.searchICD10('', 1).subscribe(r => this.icd10Results.set(r));
    this.codesService.searchCPT('', 1).subscribe(r => this.cptResults.set(r));
  }

  onSearch(q: string) { this.search$.next(q); }

  switchTab(tab: Tab) {
    this.activeTab.set(tab);
    if (this.query) this.search$.next(this.query);
  }

  changePage(type: 'icd10' | 'cpt', delta: number) {
    if (type === 'icd10') {
      this.icd10Page.update(p => p + delta);
      this.codesService.searchICD10(this.query, this.icd10Page()).subscribe(r => this.icd10Results.set(r));
    } else {
      this.cptPage.update(p => p + delta);
      this.codesService.searchCPT(this.query, this.cptPage()).subscribe(r => this.cptResults.set(r));
    }
  }

  selectCode(code: CodeEntry) { this.selectedCode.set(code); }

  clear() {
    this.query = '';
    this.globalResults.set(null);
    this.icd10Results.set(null);
    this.cptResults.set(null);
  }

  copyCode(code: string) {
    navigator.clipboard.writeText(code);
    this.copied.set(true);
    setTimeout(() => this.copied.set(false), 2000);
  }
}