feat: artifacts panel with tabbed markdown rendering

frontend/src/components/ArtifactsPanel.tsx

@@ -0,0 +1,125 @@
+import { useEffect } from 'react'
+import ReactMarkdown from 'react-markdown'
+import { IconFileText, IconRefresh } from '@tabler/icons-react'
+import { useArtifacts } from '../hooks/useArtifacts'
+
+export interface ArtifactsPanelProps {
+  sessionId: string | null
+}
+
+export function ArtifactsPanel({ sessionId }: ArtifactsPanelProps) {
+  const { artifacts, activeArtifact, refresh, loadArtifact } = useArtifacts(sessionId)
+
+  useEffect(() => {
+    if (sessionId) {
+      refresh()
+    }
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [sessionId])
+
+  if (!sessionId) {
+    return (
+      <div
+        style={{
+          padding: '2rem',
+          color: '#6a6a8a',
+          textAlign: 'center',
+        }}
+      >
+        Select a session to view artifacts
+      </div>
+    )
+  }
+
+  const count = artifacts.length
+  const countLabel = count === 1 ? '1 artifact' : `${count} artifacts`
+
+  return (
+    <div style={{ display: 'flex', flexDirection: 'column', height: '100%' }}>
+      {/* Header bar */}
+      <div
+        style={{
+          padding: '0.5rem 0.75rem',
+          borderBottom: '1px solid #2a2a4a',
+          display: 'flex',
+          justifyContent: 'space-between',
+          alignItems: 'center',
+        }}
+      >
+        <span style={{ fontSize: '0.8rem', color: '#8888aa' }}>{countLabel}</span>
+        <button
+          title="Refresh"
+          onClick={refresh}
+          style={{
+            background: 'none',
+            border: 'none',
+            color: '#7aa2f7',
+            cursor: 'pointer',
+          }}
+        >
+          <IconRefresh size={16} />
+        </button>
+      </div>
+
+      {/* Tab strip — only when there are artifacts */}
+      {artifacts.length > 0 && (
+        <div
+          style={{
+            display: 'flex',
+            gap: '2px',
+            padding: '0.3rem 0.5rem',
+            overflowX: 'auto',
+            borderBottom: '1px solid #2a2a4a',
+          }}
+        >
+          {artifacts.map((artifact) => {
+            const isActive = activeArtifact?.name === artifact.name
+            return (
+              <button
+                key={artifact.name}
+                onClick={() => loadArtifact(artifact.name)}
+                style={{
+                  background: isActive ? '#2a3a5a' : 'transparent',
+                  color: isActive ? '#ffffff' : '#8888aa',
+                  padding: '0.3rem 0.6rem',
+                  borderRadius: '4px',
+                  fontSize: '0.75rem',
+                  whiteSpace: 'nowrap',
+                  border: 'none',
+                  cursor: 'pointer',
+                  display: 'flex',
+                  alignItems: 'center',
+                  gap: '0.3rem',
+                }}
+              >
+                <IconFileText size={14} />
+                {artifact.name}
+              </button>
+            )
+          })}
+        </div>
+      )}
+
+      {/* Content area */}
+      <div style={{ flex: 1, overflowY: 'auto', padding: '1rem' }}>
+        {activeArtifact ? (
+          <div className="chat-message assistant">
+            <ReactMarkdown>{activeArtifact.content}</ReactMarkdown>
+          </div>
+        ) : artifacts.length > 0 ? (
+          <div
+            style={{ color: '#6a6a8a', textAlign: 'center', paddingTop: '2rem' }}
+          >
+            Click an artifact tab to view it
+          </div>
+        ) : (
+          <div
+            style={{ color: '#6a6a8a', textAlign: 'center', paddingTop: '2rem' }}
+          >
+            No artifacts yet. The researcher will create them during research.
+          </div>
+        )}
+      </div>
+    </div>
+  )
+}

frontend/src/test/ArtifactsPanel.test.tsx

@@ -0,0 +1,283 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { render, screen, act } from '@testing-library/react'
+import userEvent from '@testing-library/user-event'
+import type { ArtifactContent, Artifact } from '../lib/types'
+
+// Must be hoisted before imports
+vi.mock('react-markdown', () => ({
+  default: ({ children }: { children: string }) => <div>{children}</div>,
+}))
+
+vi.mock('../hooks/useArtifacts')
+
+import { ArtifactsPanel } from '../components/ArtifactsPanel'
+import { useArtifacts } from '../hooks/useArtifacts'
+
+const mockUseArtifacts = vi.mocked(useArtifacts)
+
+const mockRefresh = vi.fn()
+const mockLoadArtifact = vi.fn()
+
+function makeHookReturn(
+  artifacts: Artifact[] = [],
+  activeArtifact: ArtifactContent | null = null
+) {
+  return {
+    artifacts,
+    activeArtifact,
+    refresh: mockRefresh,
+    loadArtifact: mockLoadArtifact,
+  }
+}
+
+describe('ArtifactsPanel', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    mockUseArtifacts.mockReturnValue(makeHookReturn())
+  })
+
+  // ─── No session placeholder ───────────────────────────────────────────
+
+  describe('no-session placeholder', () => {
+    it('renders placeholder text when sessionId is null', () => {
+      render(<ArtifactsPanel sessionId={null} />)
+      expect(screen.getByText('Select a session to view artifacts')).toBeTruthy()
+    })
+
+    it('placeholder has padding 2rem', () => {
+      const { container } = render(<ArtifactsPanel sessionId={null} />)
+      const div = container.firstElementChild as HTMLElement
+      expect(div.style.padding).toBe('2rem')
+    })
+
+    it('placeholder has color #6a6a8a (rgb(106, 106, 138))', () => {
+      const { container } = render(<ArtifactsPanel sessionId={null} />)
+      const div = container.firstElementChild as HTMLElement
+      expect(div.style.color).toBe('rgb(106, 106, 138)')
+    })
+
+    it('placeholder is text-centered', () => {
+      const { container } = render(<ArtifactsPanel sessionId={null} />)
+      const div = container.firstElementChild as HTMLElement
+      expect(div.style.textAlign).toBe('center')
+    })
+
+    it('does not call refresh when sessionId is null', () => {
+      render(<ArtifactsPanel sessionId={null} />)
+      expect(mockRefresh).not.toHaveBeenCalled()
+    })
+  })
+
+  // ─── With session — useEffect ─────────────────────────────────────────
+
+  describe('with sessionId — useEffect', () => {
+    it('calls refresh when sessionId is set', async () => {
+      await act(async () => {
+        render(<ArtifactsPanel sessionId="sess-1" />)
+      })
+      expect(mockRefresh).toHaveBeenCalledTimes(1)
+    })
+
+    it('does not call refresh when sessionId is null', async () => {
+      await act(async () => {
+        render(<ArtifactsPanel sessionId={null} />)
+      })
+      expect(mockRefresh).not.toHaveBeenCalled()
+    })
+  })
+
+  // ─── Header bar ───────────────────────────────────────────────────────
+
+  describe('header bar', () => {
+    it('shows "0 artifacts" when artifacts is empty', () => {
+      render(<ArtifactsPanel sessionId="sess-1" />)
+      expect(screen.getByText('0 artifacts')).toBeTruthy()
+    })
+
+    it('shows "1 artifact" (singular) when there is one artifact', () => {
+      mockUseArtifacts.mockReturnValue(
+        makeHookReturn([{ name: 'report.md', session_id: 'sess-1', size: 100 }])
+      )
+      render(<ArtifactsPanel sessionId="sess-1" />)
+      expect(screen.getByText('1 artifact')).toBeTruthy()
+    })
+
+    it('shows "2 artifacts" (plural) when there are two artifacts', () => {
+      mockUseArtifacts.mockReturnValue(
+        makeHookReturn([
+          { name: 'report.md', session_id: 'sess-1', size: 100 },
+          { name: 'summary.md', session_id: 'sess-1', size: 200 },
+        ])
+      )
+      render(<ArtifactsPanel sessionId="sess-1" />)
+      expect(screen.getByText('2 artifacts')).toBeTruthy()
+    })
+
+    it('renders Refresh button with title "Refresh"', () => {
+      render(<ArtifactsPanel sessionId="sess-1" />)
+      expect(screen.getByTitle('Refresh')).toBeTruthy()
+    })
+
+    it('Refresh button has color #7aa2f7 (rgb(122, 162, 247))', () => {
+      render(<ArtifactsPanel sessionId="sess-1" />)
+      const btn = screen.getByTitle('Refresh') as HTMLButtonElement
+      expect(btn.style.color).toBe('rgb(122, 162, 247)')
+    })
+
+    it('Refresh button has no background', () => {
+      render(<ArtifactsPanel sessionId="sess-1" />)
+      const btn = screen.getByTitle('Refresh') as HTMLButtonElement
+      // background: 'none' normalized as empty string or 'none'
+      expect(
+        btn.style.background === 'none' || btn.style.background === ''
+      ).toBe(true)
+    })
+
+    it('clicking Refresh button calls refresh()', async () => {
+      render(<ArtifactsPanel sessionId="sess-1" />)
+      await userEvent.click(screen.getByTitle('Refresh'))
+      // refresh is also called on mount, so check at least once from click
+      expect(mockRefresh).toHaveBeenCalled()
+    })
+  })
+
+  // ─── No artifacts empty state ─────────────────────────────────────────
+
+  describe('no artifacts empty state', () => {
+    it('shows "No artifacts yet" message when artifacts array is empty', () => {
+      render(<ArtifactsPanel sessionId="sess-1" />)
+      expect(
+        screen.getByText(
+          'No artifacts yet. The researcher will create them during research.'
+        )
+      ).toBeTruthy()
+    })
+
+    it('does not render tab strip when there are no artifacts', () => {
+      const { container } = render(<ArtifactsPanel sessionId="sess-1" />)
+      // No buttons other than Refresh should be present
+      const buttons = container.querySelectorAll('button')
+      expect(buttons.length).toBe(1) // only the Refresh button
+    })
+  })
+
+  // ─── Tab strip ────────────────────────────────────────────────────────
+
+  describe('tab strip', () => {
+    const artifacts: Artifact[] = [
+      { name: 'report.md', session_id: 'sess-1', size: 100 },
+      { name: 'summary.md', session_id: 'sess-1', size: 200 },
+    ]
+
+    it('renders a tab button for each artifact', () => {
+      mockUseArtifacts.mockReturnValue(makeHookReturn(artifacts))
+      const { container } = render(<ArtifactsPanel sessionId="sess-1" />)
+      const buttons = container.querySelectorAll('button')
+      // Refresh + 2 artifact tabs
+      expect(buttons.length).toBe(3)
+    })
+
+    it('each tab shows the artifact name', () => {
+      mockUseArtifacts.mockReturnValue(makeHookReturn(artifacts))
+      render(<ArtifactsPanel sessionId="sess-1" />)
+      expect(screen.getByText('report.md')).toBeTruthy()
+      expect(screen.getByText('summary.md')).toBeTruthy()
+    })
+
+    it('clicking a tab calls loadArtifact with the artifact name', async () => {
+      mockUseArtifacts.mockReturnValue(makeHookReturn(artifacts))
+      render(<ArtifactsPanel sessionId="sess-1" />)
+      await userEvent.click(screen.getByText('report.md'))
+      expect(mockLoadArtifact).toHaveBeenCalledWith('report.md')
+    })
+
+    it('active tab has background #2a3a5a and color #ffffff', () => {
+      const activeArtifact: ArtifactContent = {
+        name: 'report.md',
+        session_id: 'sess-1',
+        content: '# Report',
+      }
+      mockUseArtifacts.mockReturnValue(makeHookReturn(artifacts, activeArtifact))
+      const { container } = render(<ArtifactsPanel sessionId="sess-1" />)
+      const buttons = container.querySelectorAll('button')
+      // buttons[0] is Refresh, buttons[1] is first artifact tab
+      const activeTab = buttons[1] as HTMLElement
+      expect(activeTab.style.background).toBe('rgb(42, 58, 90)')
+      expect(activeTab.style.color).toBe('rgb(255, 255, 255)')
+    })
+
+    it('inactive tab has transparent background and color #8888aa', () => {
+      const activeArtifact: ArtifactContent = {
+        name: 'report.md',
+        session_id: 'sess-1',
+        content: '# Report',
+      }
+      mockUseArtifacts.mockReturnValue(makeHookReturn(artifacts, activeArtifact))
+      const { container } = render(<ArtifactsPanel sessionId="sess-1" />)
+      const buttons = container.querySelectorAll('button')
+      // buttons[2] is the second (inactive) artifact tab
+      const inactiveTab = buttons[2] as HTMLElement
+      expect(inactiveTab.style.color).toBe('rgb(136, 136, 170)')
+    })
+
+    it('shows "Click an artifact tab to view it" when artifacts exist but none selected', () => {
+      mockUseArtifacts.mockReturnValue(makeHookReturn(artifacts, null))
+      render(<ArtifactsPanel sessionId="sess-1" />)
+      expect(screen.getByText('Click an artifact tab to view it')).toBeTruthy()
+    })
+  })
+
+  // ─── Content area with active artifact ───────────────────────────────
+
+  describe('content area — active artifact', () => {
+    it('renders the artifact content inside ReactMarkdown', () => {
+      const activeArtifact: ArtifactContent = {
+        name: 'report.md',
+        session_id: 'sess-1',
+        content: '# Research Report\n\nFindings here.',
+      }
+      mockUseArtifacts.mockReturnValue(
+        makeHookReturn(
+          [{ name: 'report.md', session_id: 'sess-1', size: 100 }],
+          activeArtifact
+        )
+      )
+      const { container } = render(<ArtifactsPanel sessionId="sess-1" />)
+      // The mock renders children in a div; check text content directly to handle newlines
+      const contentWrapper = container.querySelector('.chat-message.assistant') as HTMLElement
+      expect(contentWrapper).toBeTruthy()
+      expect(contentWrapper.textContent).toContain('# Research Report')
+      expect(contentWrapper.textContent).toContain('Findings here.')
+    })
+
+    it('renders content inside a div with class "chat-message assistant"', () => {
+      const activeArtifact: ArtifactContent = {
+        name: 'report.md',
+        session_id: 'sess-1',
+        content: '# Report',
+      }
+      mockUseArtifacts.mockReturnValue(
+        makeHookReturn(
+          [{ name: 'report.md', session_id: 'sess-1', size: 100 }],
+          activeArtifact
+        )
+      )
+      const { container } = render(<ArtifactsPanel sessionId="sess-1" />)
+      expect(container.querySelector('.chat-message.assistant')).toBeTruthy()
+    })
+  })
+
+  // ─── useArtifacts integration ─────────────────────────────────────────
+
+  describe('useArtifacts integration', () => {
+    it('passes sessionId to useArtifacts', () => {
+      render(<ArtifactsPanel sessionId="sess-42" />)
+      expect(mockUseArtifacts).toHaveBeenCalledWith('sess-42')
+    })
+
+    it('passes null to useArtifacts when sessionId is null', () => {
+      render(<ArtifactsPanel sessionId={null} />)
+      expect(mockUseArtifacts).toHaveBeenCalledWith(null)
+    })
+  })
+})