refactor(prd-editor): modularize PRD editor with typed feature modules

Break the legacy PRDEditor.jsx monolith into a feature-based TypeScript architecture under src/components/prd-editor while keeping behavior parity and readability.

Key changes:

- Replace PRDEditor.jsx with a typed orchestrator component and a compatibility export bridge at src/components/PRDEditor.tsx.

- Split responsibilities into dedicated hooks: document loading/init, existing PRD registry fetching, save workflow with overwrite detection, and keyboard shortcuts.

- Split UI into focused view components: header, editor/preview body, footer stats, loading state, generate-tasks modal, and overwrite-confirm modal.

- Move filename concerns into utility helpers (sanitize, extension handling, default naming) and centralize template/constants.

- Keep component-local state close to the UI that owns it (workspace controls/modal toggles), while shared workflow state remains in the feature container.

- Reuse the existing MarkdownPreview component for safer markdown rendering instead of ad-hoc HTML conversion.

- Update TaskMasterPanel integration to consume typed PRDEditor directly (remove any-cast) and pass isExisting metadata for correct overwrite behavior.

- Keep all new/changed files below 300 lines and add targeted comments where behavior needs clarification.

Validation:

- npm run typecheck

- npm run build

src/components/prd-editor/PRDEditor.tsx

@@ -0,0 +1,138 @@
+import { useCallback, useMemo, useState } from 'react';
+import type { Project } from '../../types/app';
+import { usePrdDocument } from './hooks/usePrdDocument';
+import { usePrdKeyboardShortcuts } from './hooks/usePrdKeyboardShortcuts';
+import { usePrdRegistry } from './hooks/usePrdRegistry';
+import { usePrdSave } from './hooks/usePrdSave';
+import type { PrdFile } from './types';
+import { ensurePrdExtension } from './utils/fileName';
+import OverwriteConfirmModal from './view/OverwriteConfirmModal';
+import PrdEditorLoadingState from './view/PrdEditorLoadingState';
+import PrdEditorWorkspace from './view/PrdEditorWorkspace';
+
+type PRDEditorProps = {
+  file?: PrdFile | null;
+  onClose: () => void;
+  projectPath?: string;
+  project?: Project | null;
+  initialContent?: string;
+  isNewFile?: boolean;
+  onSave?: () => Promise<void> | void;
+};
+
+export default function PRDEditor({
+  file,
+  onClose,
+  projectPath,
+  project,
+  initialContent = '',
+  isNewFile = false,
+  onSave,
+}: PRDEditorProps) {
+  const [showOverwriteConfirm, setShowOverwriteConfirm] = useState<boolean>(false);
+  const [overwriteFileName, setOverwriteFileName] = useState<string>('');
+
+  const { content, setContent, fileName, setFileName, loading, loadError } = usePrdDocument({
+    file,
+    isNewFile,
+    initialContent,
+    projectPath,
+  });
+
+  const { existingPrds, refreshExistingPrds } = usePrdRegistry({
+    projectName: project?.name,
+  });
+
+  const isExistingFile = useMemo(() => !isNewFile || Boolean(file?.isExisting), [file?.isExisting, isNewFile]);
+
+  const { savePrd, saving, saveSuccess } = usePrdSave({
+    projectName: project?.name,
+    existingPrds,
+    isExistingFile,
+    onAfterSave: async () => {
+      await refreshExistingPrds();
+      await onSave?.();
+    },
+  });
+
+  const handleDownload = useCallback(() => {
+    const blob = new Blob([content], { type: 'text/markdown' });
+    const url = URL.createObjectURL(blob);
+    const anchor = document.createElement('a');
+    const downloadedFileName = ensurePrdExtension(fileName || 'prd');
+
+    anchor.href = url;
+    anchor.download = downloadedFileName;
+    document.body.appendChild(anchor);
+    anchor.click();
+    document.body.removeChild(anchor);
+    URL.revokeObjectURL(url);
+  }, [content, fileName]);
+
+  const handleSave = useCallback(
+    async (allowOverwrite = false) => {
+      const result = await savePrd({
+        content,
+        fileName,
+        allowOverwrite,
+      });
+
+      if (result.status === 'needs-overwrite') {
+        setOverwriteFileName(result.fileName);
+        setShowOverwriteConfirm(true);
+        return;
+      }
+
+      if (result.status === 'failed') {
+        alert(result.message);
+      }
+    },
+    [content, fileName, savePrd],
+  );
+
+  const confirmOverwrite = useCallback(async () => {
+    setShowOverwriteConfirm(false);
+    await handleSave(true);
+  }, [handleSave]);
+
+  usePrdKeyboardShortcuts({
+    onSave: () => {
+      void handleSave();
+    },
+    onClose,
+  });
+
+  if (loading) {
+    return <PrdEditorLoadingState />;
+  }
+
+  return (
+    <>
+      <PrdEditorWorkspace
+        content={content}
+        onContentChange={setContent}
+        fileName={fileName}
+        onFileNameChange={setFileName}
+        isNewFile={isNewFile}
+        saving={saving}
+        saveSuccess={saveSuccess}
+        onSave={() => {
+          void handleSave();
+        }}
+        onDownload={handleDownload}
+        onClose={onClose}
+        loadError={loadError}
+      />
+
+      <OverwriteConfirmModal
+        isOpen={showOverwriteConfirm}
+        fileName={overwriteFileName || ensurePrdExtension(fileName || 'prd')}
+        saving={saving}
+        onCancel={() => setShowOverwriteConfirm(false)}
+        onConfirm={() => {
+          void confirmOverwrite();
+        }}
+      />
+    </>
+  );
+}

src/components/prd-editor/constants.ts

@@ -0,0 +1,67 @@
+export const PRD_TEMPLATE = `# Product Requirements Document
+
+## 1. Overview
+- Product Name:
+- Owner:
+- Last Updated:
+- Version:
+
+Describe what problem this product solves and who it serves.
+
+## 2. Objectives
+- Primary objective:
+- Secondary objective:
+- Out-of-scope:
+
+## 3. User Stories
+- As a <role>, I want <capability>, so that <benefit>.
+- As a <role>, I want <capability>, so that <benefit>.
+
+## 4. Functional Requirements
+### Core Requirements
+- Requirement 1
+- Requirement 2
+
+### Edge Cases
+- Edge case 1
+- Edge case 2
+
+## 5. Non-Functional Requirements
+- Performance:
+- Security:
+- Reliability:
+- Accessibility:
+
+## 6. Success Metrics
+- Metric 1:
+- Metric 2:
+
+## 7. Technical Notes
+- Architecture constraints:
+- Dependencies:
+- Integration points:
+
+## 8. Release Plan
+### Milestone 1
+- Scope:
+- Exit criteria:
+
+### Milestone 2
+- Scope:
+- Exit criteria:
+
+## 9. Risks and Mitigations
+- Risk:
+  - Impact:
+  - Mitigation:
+
+## 10. Open Questions
+- Question 1
+- Question 2
+`;
+
+export const PRD_DOCS_URL =
+  'https://github.com/eyaltoledano/claude-task-master/blob/main/docs/examples.md';
+
+export const INVALID_FILE_NAME_CHARACTERS = /[<>:"/\\|?*]/g;
+export const PRD_EXTENSION_PATTERN = /\.(txt|md)$/i;

src/components/prd-editor/hooks/usePrdDocument.ts

@@ -0,0 +1,132 @@
+import { useCallback, useEffect, useState } from 'react';
+import { api } from '../../../utils/api';
+import { PRD_TEMPLATE } from '../constants';
+import type { PrdFile } from '../types';
+import { createDefaultPrdName, sanitizeFileName, stripPrdExtension } from '../utils/fileName';
+
+type UsePrdDocumentArgs = {
+  file?: PrdFile | null;
+  isNewFile: boolean;
+  initialContent: string;
+  projectPath?: string;
+};
+
+type UsePrdDocumentResult = {
+  content: string;
+  setContent: (nextContent: string) => void;
+  fileName: string;
+  setFileName: (nextFileName: string) => void;
+  loading: boolean;
+  loadError: string | null;
+};
+
+export function usePrdDocument({
+  file,
+  isNewFile,
+  initialContent,
+  projectPath,
+}: UsePrdDocumentArgs): UsePrdDocumentResult {
+  const [content, setContent] = useState<string>(initialContent || '');
+  const [fileName, setFileNameState] = useState<string>('');
+  const [loading, setLoading] = useState<boolean>(!isNewFile);
+  const [loadError, setLoadError] = useState<string | null>(null);
+
+  const setFileName = useCallback((nextFileName: string) => {
+    setFileNameState(sanitizeFileName(nextFileName));
+  }, []);
+
+  useEffect(() => {
+    let isMounted = true;
+
+    const initialize = async () => {
+      const defaultName = file?.name
+        ? stripPrdExtension(file.name)
+        : createDefaultPrdName(new Date());
+
+      if (isMounted) {
+        setFileNameState(defaultName);
+      }
+
+      // Loading precedence:
+      // 1) new file -> initial content or template
+      // 2) provided content -> use it directly
+      // 3) legacy file path -> fetch from API
+      if (isNewFile) {
+        if (!isMounted) {
+          return;
+        }
+
+        setContent(initialContent || PRD_TEMPLATE);
+        setLoadError(null);
+        setLoading(false);
+        return;
+      }
+
+      if (file?.content) {
+        if (!isMounted) {
+          return;
+        }
+
+        setContent(file.content);
+        setLoadError(null);
+        setLoading(false);
+        return;
+      }
+
+      if (!file?.projectName || !file?.path) {
+        if (!isMounted) {
+          return;
+        }
+
+        setContent(initialContent || PRD_TEMPLATE);
+        setLoadError(null);
+        setLoading(false);
+        return;
+      }
+
+      try {
+        setLoading(true);
+
+        const response = await api.readFile(file.projectName, file.path);
+        if (!response.ok) {
+          throw new Error(`Failed to load file: ${response.status} ${response.statusText}`);
+        }
+
+        const data = (await response.json()) as { content?: string };
+        if (!isMounted) {
+          return;
+        }
+
+        setContent(data.content || PRD_TEMPLATE);
+        setLoadError(null);
+      } catch (error) {
+        const message = error instanceof Error ? error.message : 'Unknown error';
+        if (!isMounted) {
+          return;
+        }
+
+        setContent(initialContent || PRD_TEMPLATE);
+        setLoadError(`Unable to load file content: ${message}`);
+      } finally {
+        if (isMounted) {
+          setLoading(false);
+        }
+      }
+    };
+
+    void initialize();
+
+    return () => {
+      isMounted = false;
+    };
+  }, [file, initialContent, isNewFile, projectPath]);
+
+  return {
+    content,
+    setContent,
+    fileName,
+    setFileName,
+    loading,
+    loadError,
+  };
+}

src/components/prd-editor/hooks/usePrdKeyboardShortcuts.ts

@@ -0,0 +1,34 @@
+import { useEffect } from 'react';
+
+type UsePrdKeyboardShortcutsArgs = {
+  onSave: () => void;
+  onClose: () => void;
+};
+
+export function usePrdKeyboardShortcuts({
+  onSave,
+  onClose,
+}: UsePrdKeyboardShortcutsArgs): void {
+  useEffect(() => {
+    // Keep shortcuts global so the editor behaves consistently in fullscreen and modal mode.
+    const handleKeyDown = (event: KeyboardEvent) => {
+      const loweredKey = event.key.toLowerCase();
+
+      if ((event.ctrlKey || event.metaKey) && loweredKey === 's') {
+        event.preventDefault();
+        onSave();
+        return;
+      }
+
+      if (event.key === 'Escape') {
+        event.preventDefault();
+        onClose();
+      }
+    };
+
+    document.addEventListener('keydown', handleKeyDown);
+    return () => {
+      document.removeEventListener('keydown', handleKeyDown);
+    };
+  }, [onClose, onSave]);
+}

src/components/prd-editor/hooks/usePrdRegistry.ts

@@ -0,0 +1,50 @@
+import { useCallback, useEffect, useState } from 'react';
+import { api } from '../../../utils/api';
+import type { ExistingPrdFile, PrdListResponse } from '../types';
+
+type UsePrdRegistryArgs = {
+  projectName?: string;
+};
+
+type UsePrdRegistryResult = {
+  existingPrds: ExistingPrdFile[];
+  refreshExistingPrds: () => Promise<void>;
+};
+
+function getPrdFiles(data: PrdListResponse): ExistingPrdFile[] {
+  return data.prdFiles || data.prds || [];
+}
+
+export function usePrdRegistry({ projectName }: UsePrdRegistryArgs): UsePrdRegistryResult {
+  const [existingPrds, setExistingPrds] = useState<ExistingPrdFile[]>([]);
+
+  const refreshExistingPrds = useCallback(async () => {
+    if (!projectName) {
+      setExistingPrds([]);
+      return;
+    }
+
+    try {
+      const response = await api.get(`/taskmaster/prd/${encodeURIComponent(projectName)}`);
+      if (!response.ok) {
+        setExistingPrds([]);
+        return;
+      }
+
+      const data = (await response.json()) as PrdListResponse;
+      setExistingPrds(getPrdFiles(data));
+    } catch (error) {
+      console.error('Failed to fetch existing PRDs:', error);
+      setExistingPrds([]);
+    }
+  }, [projectName]);
+
+  useEffect(() => {
+    void refreshExistingPrds();
+  }, [refreshExistingPrds]);
+
+  return {
+    existingPrds,
+    refreshExistingPrds,
+  };
+}

src/components/prd-editor/hooks/usePrdSave.ts

@@ -0,0 +1,111 @@
+import { useCallback, useEffect, useRef, useState } from 'react';
+import { authenticatedFetch } from '../../../utils/api';
+import type { ExistingPrdFile, SavePrdInput, SavePrdResult } from '../types';
+import { ensurePrdExtension } from '../utils/fileName';
+
+type UsePrdSaveArgs = {
+  projectName?: string;
+  existingPrds: ExistingPrdFile[];
+  isExistingFile: boolean;
+  onAfterSave?: () => Promise<void>;
+};
+
+type UsePrdSaveResult = {
+  savePrd: (input: SavePrdInput) => Promise<SavePrdResult>;
+  saving: boolean;
+  saveSuccess: boolean;
+};
+
+export function usePrdSave({
+  projectName,
+  existingPrds,
+  isExistingFile,
+  onAfterSave,
+}: UsePrdSaveArgs): UsePrdSaveResult {
+  const [saving, setSaving] = useState<boolean>(false);
+  const [saveSuccess, setSaveSuccess] = useState<boolean>(false);
+  const saveSuccessTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null);
+
+  useEffect(() => {
+    return () => {
+      if (saveSuccessTimeoutRef.current) {
+        clearTimeout(saveSuccessTimeoutRef.current);
+      }
+    };
+  }, []);
+
+  const savePrd = useCallback(
+    async ({ content, fileName, allowOverwrite = false }: SavePrdInput): Promise<SavePrdResult> => {
+      if (!content.trim()) {
+        return { status: 'failed', message: 'Please add content before saving.' };
+      }
+
+      if (!fileName.trim()) {
+        return { status: 'failed', message: 'Please provide a filename for the PRD.' };
+      }
+
+      if (!projectName) {
+        return { status: 'failed', message: 'No project selected. Please reopen the editor.' };
+      }
+
+      const finalFileName = ensurePrdExtension(fileName.trim());
+      const hasConflict = existingPrds.some((prd) => prd.name === finalFileName);
+
+      // Overwrite confirmation is only required when creating a brand-new PRD.
+      if (hasConflict && !allowOverwrite && !isExistingFile) {
+        return { status: 'needs-overwrite', fileName: finalFileName };
+      }
+
+      setSaving(true);
+
+      try {
+        const response = await authenticatedFetch(`/api/taskmaster/prd/${encodeURIComponent(projectName)}`, {
+          method: 'POST',
+          body: JSON.stringify({
+            fileName: finalFileName,
+            content,
+          }),
+        });
+
+        if (!response.ok) {
+          const fallbackMessage = `Save failed: ${response.status}`;
+
+          try {
+            const errorData = (await response.json()) as { message?: string };
+            return { status: 'failed', message: errorData.message || fallbackMessage };
+          } catch {
+            return { status: 'failed', message: fallbackMessage };
+          }
+        }
+
+        if (saveSuccessTimeoutRef.current) {
+          clearTimeout(saveSuccessTimeoutRef.current);
+        }
+
+        setSaveSuccess(true);
+        saveSuccessTimeoutRef.current = setTimeout(() => {
+          setSaveSuccess(false);
+          saveSuccessTimeoutRef.current = null;
+        }, 2000);
+
+        if (onAfterSave) {
+          await onAfterSave();
+        }
+
+        return { status: 'saved', fileName: finalFileName };
+      } catch (error) {
+        const message = error instanceof Error ? error.message : 'Unknown error';
+        return { status: 'failed', message: `Error saving PRD: ${message}` };
+      } finally {
+        setSaving(false);
+      }
+    },
+    [existingPrds, isExistingFile, onAfterSave, projectName],
+  );
+
+  return {
+    savePrd,
+    saving,
+    saveSuccess,
+  };
+}

src/components/prd-editor/index.ts

@@ -0,0 +1 @@
+export { default } from './PRDEditor';

src/components/prd-editor/types.ts

@@ -0,0 +1,30 @@
+export type PrdFile = {
+  name?: string;
+  path?: string;
+  projectName?: string;
+  content?: string;
+  isExisting?: boolean;
+};
+
+export type ExistingPrdFile = {
+  name: string;
+  content?: string;
+  isExisting?: boolean;
+  [key: string]: unknown;
+};
+
+export type PrdListResponse = {
+  prdFiles?: ExistingPrdFile[];
+  prds?: ExistingPrdFile[];
+};
+
+export type SavePrdInput = {
+  content: string;
+  fileName: string;
+  allowOverwrite?: boolean;
+};
+
+export type SavePrdResult =
+  | { status: 'saved'; fileName: string }
+  | { status: 'needs-overwrite'; fileName: string }
+  | { status: 'failed'; message: string };

src/components/prd-editor/utils/fileName.ts

@@ -0,0 +1,18 @@
+import { INVALID_FILE_NAME_CHARACTERS, PRD_EXTENSION_PATTERN } from '../constants';
+
+export function sanitizeFileName(value: string): string {
+  return value.replace(INVALID_FILE_NAME_CHARACTERS, '');
+}
+
+export function stripPrdExtension(value: string): string {
+  return value.replace(PRD_EXTENSION_PATTERN, '');
+}
+
+export function ensurePrdExtension(value: string): string {
+  return PRD_EXTENSION_PATTERN.test(value) ? value : `${value}.txt`;
+}
+
+export function createDefaultPrdName(date: Date): string {
+  const isoDate = date.toISOString().split('T')[0];
+  return `prd-${isoDate}`;
+}

src/components/prd-editor/view/GenerateTasksModal.tsx

@@ -0,0 +1,77 @@
+import { Sparkles, X } from 'lucide-react';
+import { PRD_DOCS_URL } from '../constants';
+
+type GenerateTasksModalProps = {
+  isOpen: boolean;
+  fileName: string;
+  onClose: () => void;
+};
+
+export default function GenerateTasksModal({
+  isOpen,
+  fileName,
+  onClose,
+}: GenerateTasksModalProps) {
+  if (!isOpen) {
+    return null;
+  }
+
+  return (
+    <div className="fixed inset-0 bg-black/50 backdrop-blur-sm flex items-center justify-center z-[300] p-4">
+      <div className="bg-white dark:bg-gray-800 rounded-lg shadow-xl w-full max-w-md border border-gray-200 dark:border-gray-700">
+        <div className="flex items-center justify-between p-6 border-b border-gray-200 dark:border-gray-700">
+          <div className="flex items-center gap-3">
+            <div className="w-8 h-8 bg-purple-100 dark:bg-purple-900/50 rounded-lg flex items-center justify-center">
+              <Sparkles className="w-4 h-4 text-purple-600 dark:text-purple-400" />
+            </div>
+            <h3 className="text-lg font-semibold text-gray-900 dark:text-white">
+              Generate Tasks from PRD
+            </h3>
+          </div>
+          <button
+            onClick={onClose}
+            className="p-2 text-gray-400 hover:text-gray-600 dark:hover:text-gray-300 rounded-md hover:bg-gray-100 dark:hover:bg-gray-700"
+          >
+            <X className="w-5 h-5" />
+          </button>
+        </div>
+
+        <div className="p-6 space-y-4">
+          <div className="bg-purple-50 dark:bg-purple-900/20 rounded-lg p-4 border border-purple-200 dark:border-purple-800">
+            <h4 className="font-semibold text-purple-900 dark:text-purple-100 mb-2">
+              Ask Claude Code directly
+            </h4>
+            <p className="text-sm text-purple-800 dark:text-purple-200 mb-3">
+              Save this PRD, then ask Claude Code in chat to parse the file and create your initial tasks.
+            </p>
+
+            <div className="bg-white dark:bg-gray-800 rounded border border-purple-200 dark:border-purple-700 p-3">
+              <p className="text-xs font-medium text-gray-600 dark:text-gray-400 mb-1">Example prompt</p>
+              <p className="text-xs text-gray-900 dark:text-white font-mono">
+                I have a PRD at .taskmaster/docs/{fileName}. Parse it and create the initial tasks.
+              </p>
+            </div>
+          </div>
+
+          <div className="text-center pt-4 border-t border-gray-200 dark:border-gray-700">
+            <a
+              href={PRD_DOCS_URL}
+              target="_blank"
+              rel="noopener noreferrer"
+              className="inline-block text-sm text-purple-600 dark:text-purple-400 hover:text-purple-700 dark:hover:text-purple-300 underline font-medium"
+            >
+              View TaskMaster documentation
+            </a>
+          </div>
+
+          <button
+            onClick={onClose}
+            className="w-full px-4 py-2 text-sm font-medium text-gray-700 dark:text-gray-300 bg-white dark:bg-gray-700 border border-gray-300 dark:border-gray-600 rounded-lg hover:bg-gray-50 dark:hover:bg-gray-600 transition-colors"
+          >
+            Got it
+          </button>
+        </div>
+      </div>
+    </div>
+  );
+}

src/components/prd-editor/view/OverwriteConfirmModal.tsx

@@ -0,0 +1,60 @@
+import { AlertTriangle, Save } from 'lucide-react';
+
+type OverwriteConfirmModalProps = {
+  isOpen: boolean;
+  fileName: string;
+  saving: boolean;
+  onCancel: () => void;
+  onConfirm: () => void;
+};
+
+export default function OverwriteConfirmModal({
+  isOpen,
+  fileName,
+  saving,
+  onCancel,
+  onConfirm,
+}: OverwriteConfirmModalProps) {
+  if (!isOpen) {
+    return null;
+  }
+
+  return (
+    <div className="fixed inset-0 z-[300] flex items-center justify-center p-4">
+      <div className="fixed inset-0 bg-black/50" onClick={onCancel} />
+
+      <div className="relative bg-white dark:bg-gray-800 rounded-lg shadow-xl max-w-md w-full border border-gray-200 dark:border-gray-700">
+        <div className="p-6">
+          <div className="flex items-center mb-4">
+            <div className="p-2 rounded-full mr-3 bg-yellow-100 dark:bg-yellow-900">
+              <AlertTriangle className="w-5 h-5 text-yellow-600 dark:text-yellow-400" />
+            </div>
+            <h3 className="text-lg font-semibold text-gray-900 dark:text-white">File Already Exists</h3>
+          </div>
+
+          <p className="text-sm text-gray-600 dark:text-gray-400 mb-6">
+            A PRD named "{fileName}" already exists. Do you want to overwrite it?
+          </p>
+
+          <div className="flex justify-end gap-3">
+            <button
+              onClick={onCancel}
+              disabled={saving}
+              className="px-4 py-2 text-sm text-gray-700 dark:text-gray-300 bg-white dark:bg-gray-700 border border-gray-300 dark:border-gray-600 rounded-md hover:bg-gray-50 dark:hover:bg-gray-600 transition-colors"
+            >
+              Cancel
+            </button>
+            <button
+              onClick={onConfirm}
+              disabled={saving}
+              className="px-4 py-2 text-sm text-white bg-yellow-600 hover:bg-yellow-700 rounded-md flex items-center gap-2 transition-colors disabled:opacity-50"
+            >
+              <Save className="w-4 h-4" />
+              <span>{saving ? 'Saving...' : 'Overwrite'}</span>
+            </button>
+          </div>
+        </div>
+      </div>
+    </div>
+  );
+}

src/components/prd-editor/view/PrdEditorBody.tsx

@@ -0,0 +1,61 @@
+import { useMemo } from 'react';
+import { markdown } from '@codemirror/lang-markdown';
+import { oneDark } from '@codemirror/theme-one-dark';
+import { EditorView } from '@codemirror/view';
+import CodeMirror from '@uiw/react-codemirror';
+import MarkdownPreview from '../../code-editor/view/subcomponents/markdown/MarkdownPreview';
+
+type PrdEditorBodyProps = {
+  content: string;
+  onContentChange: (nextContent: string) => void;
+  previewMode: boolean;
+  isDarkMode: boolean;
+  wordWrap: boolean;
+};
+
+export default function PrdEditorBody({
+  content,
+  onContentChange,
+  previewMode,
+  isDarkMode,
+  wordWrap,
+}: PrdEditorBodyProps) {
+  const extensions = useMemo(
+    () => [markdown(), ...(wordWrap ? [EditorView.lineWrapping] : [])],
+    [wordWrap],
+  );
+
+  if (previewMode) {
+    return (
+      <div className="h-full overflow-y-auto p-6 prose prose-gray dark:prose-invert max-w-none">
+        <MarkdownPreview content={content} />
+      </div>
+    );
+  }
+
+  return (
+    <CodeMirror
+      value={content}
+      onChange={onContentChange}
+      extensions={extensions}
+      theme={isDarkMode ? oneDark : undefined}
+      height="100%"
+      style={{
+        fontSize: '14px',
+        height: '100%',
+      }}
+      basicSetup={{
+        lineNumbers: true,
+        foldGutter: true,
+        dropCursor: false,
+        allowMultipleSelections: false,
+        indentOnInput: true,
+        bracketMatching: true,
+        closeBrackets: true,
+        autocompletion: true,
+        highlightSelectionMatches: true,
+        searchKeymap: true,
+      }}
+    />
+  );
+}

src/components/prd-editor/view/PrdEditorFooter.tsx

@@ -0,0 +1,36 @@
+import { useMemo } from 'react';
+
+type PrdEditorFooterProps = {
+  content: string;
+};
+
+type ContentStats = {
+  lines: number;
+  characters: number;
+  words: number;
+};
+
+function getContentStats(content: string): ContentStats {
+  return {
+    lines: content.split('\n').length,
+    characters: content.length,
+    words: content.split(/\s+/).filter(Boolean).length,
+  };
+}
+
+export default function PrdEditorFooter({ content }: PrdEditorFooterProps) {
+  const stats = useMemo(() => getContentStats(content), [content]);
+
+  return (
+    <div className="flex items-center justify-between p-3 border-t border-gray-200 dark:border-gray-700 bg-gray-50 dark:bg-gray-800 flex-shrink-0">
+      <div className="flex items-center gap-4 text-sm text-gray-600 dark:text-gray-400">
+        <span>Lines: {stats.lines}</span>
+        <span>Characters: {stats.characters}</span>
+        <span>Words: {stats.words}</span>
+        <span>Format: Markdown</span>
+      </div>
+
+      <div className="text-sm text-gray-500 dark:text-gray-400">Press Ctrl+S to save and Esc to close</div>
+    </div>
+  );
+}

src/components/prd-editor/view/PrdEditorHeader.tsx

@@ -0,0 +1,228 @@
+import { useRef } from 'react';
+import type { ReactNode } from 'react';
+import {
+  Download,
+  Eye,
+  FileText,
+  Maximize2,
+  Minimize2,
+  Moon,
+  Save,
+  Sparkles,
+  Sun,
+  X,
+} from 'lucide-react';
+import { cn } from '../../../lib/utils';
+
+type PrdEditorHeaderProps = {
+  fileName: string;
+  onFileNameChange: (nextFileName: string) => void;
+  isNewFile: boolean;
+  previewMode: boolean;
+  onTogglePreview: () => void;
+  wordWrap: boolean;
+  onToggleWordWrap: () => void;
+  isDarkMode: boolean;
+  onToggleTheme: () => void;
+  onDownload: () => void;
+  onOpenGenerateTasks: () => void;
+  canGenerateTasks: boolean;
+  onSave: () => void;
+  saving: boolean;
+  saveSuccess: boolean;
+  isFullscreen: boolean;
+  onToggleFullscreen: () => void;
+  onClose: () => void;
+};
+
+type HeaderIconButtonProps = {
+  title: string;
+  onClick: () => void;
+  icon: ReactNode;
+  active?: boolean;
+};
+
+function HeaderIconButton({ title, onClick, icon, active = false }: HeaderIconButtonProps) {
+  return (
+    <button
+      onClick={onClick}
+      title={title}
+      className={cn(
+        'p-2 rounded-md min-w-[44px] min-h-[44px] md:min-w-0 md:min-h-0 flex items-center justify-center transition-colors',
+        active
+          ? 'text-purple-600 dark:text-purple-400 bg-purple-50 dark:bg-purple-900/50'
+          : 'text-gray-600 dark:text-gray-400 hover:text-gray-900 dark:hover:text-white hover:bg-gray-100 dark:hover:bg-gray-800',
+      )}
+    >
+      {icon}
+    </button>
+  );
+}
+
+export default function PrdEditorHeader({
+  fileName,
+  onFileNameChange,
+  isNewFile,
+  previewMode,
+  onTogglePreview,
+  wordWrap,
+  onToggleWordWrap,
+  isDarkMode,
+  onToggleTheme,
+  onDownload,
+  onOpenGenerateTasks,
+  canGenerateTasks,
+  onSave,
+  saving,
+  saveSuccess,
+  isFullscreen,
+  onToggleFullscreen,
+  onClose,
+}: PrdEditorHeaderProps) {
+  const fileNameInputRef = useRef<HTMLInputElement | null>(null);
+
+  return (
+    <div className="flex items-center justify-between p-4 border-b border-gray-200 dark:border-gray-700 flex-shrink-0 min-w-0">
+      <div className="flex items-center gap-3 min-w-0 flex-1">
+        <div className="w-8 h-8 bg-purple-600 rounded flex items-center justify-center flex-shrink-0">
+          <FileText className="w-4 h-4 text-white" />
+        </div>
+
+        <div className="min-w-0 flex-1">
+          <div className="flex flex-col sm:flex-row sm:items-center gap-2 min-w-0">
+            <div className="flex items-center gap-1 min-w-0 flex-1">
+              <div className="flex items-center min-w-0 flex-1 bg-gray-50 dark:bg-gray-700 border border-gray-200 dark:border-gray-600 rounded-md px-3 py-2 focus-within:ring-2 focus-within:ring-purple-500 focus-within:border-purple-500 dark:focus-within:ring-purple-400 dark:focus-within:border-purple-400">
+                <input
+                  ref={fileNameInputRef}
+                  type="text"
+                  value={fileName}
+                  onChange={(event) => onFileNameChange(event.target.value)}
+                  className="font-medium text-gray-900 dark:text-white bg-transparent border-none outline-none min-w-0 flex-1 text-base sm:text-sm placeholder-gray-400 dark:placeholder-gray-500"
+                  placeholder="Enter PRD filename"
+                  maxLength={100}
+                />
+                <span className="text-sm sm:text-xs text-gray-500 dark:text-gray-400 whitespace-nowrap ml-1">
+                  .txt
+                </span>
+              </div>
+
+              <button
+                onClick={() => fileNameInputRef.current?.focus()}
+                className="p-1 text-gray-400 hover:text-purple-600 dark:hover:text-purple-400 transition-colors"
+                title="Focus filename input"
+              >
+                <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                  <path
+                    strokeLinecap="round"
+                    strokeLinejoin="round"
+                    strokeWidth={2}
+                    d="M15.232 5.232l3.536 3.536m-2.036-5.036a2.5 2.5 0 113.536 3.536L6.5 21.036H3v-3.572L16.732 3.732z"
+                  />
+                </svg>
+              </button>
+            </div>
+
+            <div className="flex items-center gap-2 flex-shrink-0">
+              <span className="text-xs bg-purple-100 dark:bg-purple-900 text-purple-600 dark:text-purple-300 px-2 py-1 rounded whitespace-nowrap">
+                PRD
+              </span>
+              {isNewFile && (
+                <span className="text-xs bg-green-100 dark:bg-green-900 text-green-600 dark:text-green-300 px-2 py-1 rounded whitespace-nowrap">
+                  New
+                </span>
+              )}
+            </div>
+          </div>
+
+          <p className="text-xs sm:text-sm text-gray-500 dark:text-gray-400 truncate mt-1">
+            Product Requirements Document
+          </p>
+        </div>
+      </div>
+
+      <div className="flex items-center gap-1 md:gap-2 flex-shrink-0">
+        <HeaderIconButton
+          title={previewMode ? 'Switch to edit mode' : 'Preview markdown'}
+          onClick={onTogglePreview}
+          icon={<Eye className="w-5 h-5 md:w-4 md:h-4" />}
+          active={previewMode}
+        />
+
+        <HeaderIconButton
+          title={wordWrap ? 'Disable word wrap' : 'Enable word wrap'}
+          onClick={onToggleWordWrap}
+          icon={<span className="text-sm md:text-xs font-mono font-bold">WRAP</span>}
+          active={wordWrap}
+        />
+
+        <HeaderIconButton
+          title="Toggle theme"
+          onClick={onToggleTheme}
+          icon={
+            isDarkMode ? (
+              <Sun className="w-5 h-5 md:w-4 md:h-4" />
+            ) : (
+              <Moon className="w-5 h-5 md:w-4 md:h-4" />
+            )
+          }
+        />
+
+        <HeaderIconButton
+          title="Download PRD"
+          onClick={onDownload}
+          icon={<Download className="w-5 h-5 md:w-4 md:h-4" />}
+        />
+
+        <button
+          onClick={onOpenGenerateTasks}
+          disabled={!canGenerateTasks}
+          className={cn(
+            'px-3 py-2 rounded-md disabled:opacity-50 flex items-center gap-2 transition-colors text-sm font-medium text-white min-h-[44px] md:min-h-0',
+            'bg-purple-600 hover:bg-purple-700',
+          )}
+          title="Generate tasks from PRD content"
+        >
+          <Sparkles className="w-4 h-4" />
+          <span className="hidden md:inline">Generate Tasks</span>
+        </button>
+
+        <button
+          onClick={onSave}
+          disabled={saving}
+          className={cn(
+            'px-3 py-2 text-white rounded-md disabled:opacity-50 flex items-center gap-2 transition-colors min-h-[44px] md:min-h-0',
+            saveSuccess ? 'bg-green-600 hover:bg-green-700' : 'bg-purple-600 hover:bg-purple-700',
+          )}
+        >
+          {saveSuccess ? (
+            <>
+              <svg className="w-5 h-5 md:w-4 md:h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M5 13l4 4L19 7" />
+              </svg>
+              <span className="hidden sm:inline">Saved!</span>
+            </>
+          ) : (
+            <>
+              <Save className="w-5 h-5 md:w-4 md:h-4" />
+              <span className="hidden sm:inline">{saving ? 'Saving...' : 'Save PRD'}</span>
+            </>
+          )}
+        </button>
+
+        <button
+          onClick={onToggleFullscreen}
+          className="hidden md:flex p-2 text-gray-600 dark:text-gray-400 hover:text-gray-900 dark:hover:text-white rounded-md hover:bg-gray-100 dark:hover:bg-gray-800 items-center justify-center"
+          title={isFullscreen ? 'Exit fullscreen' : 'Fullscreen'}
+        >
+          {isFullscreen ? <Minimize2 className="w-4 h-4" /> : <Maximize2 className="w-4 h-4" />}
+        </button>
+
+        <HeaderIconButton
+          title="Close"
+          onClick={onClose}
+          icon={<X className="w-6 h-6 md:w-4 md:h-4" />}
+        />
+      </div>
+    </div>
+  );
+}

src/components/prd-editor/view/PrdEditorLoadingState.tsx

@@ -0,0 +1,12 @@
+export default function PrdEditorLoadingState() {
+  return (
+    <div className="fixed inset-0 z-[200] md:bg-black/50 md:flex md:items-center md:justify-center">
+      <div className="w-full h-full md:rounded-lg md:w-auto md:h-auto p-8 flex items-center justify-center bg-white dark:bg-gray-900">
+        <div className="flex items-center gap-3">
+          <div className="animate-spin rounded-full h-6 w-6 border-b-2 border-blue-600" />
+          <span className="text-gray-900 dark:text-white">Loading PRD...</span>
+        </div>
+      </div>
+    </div>
+  );
+}

src/components/prd-editor/view/PrdEditorWorkspace.tsx

@@ -0,0 +1,114 @@
+import { useState } from 'react';
+import { cn } from '../../../lib/utils';
+import { ensurePrdExtension } from '../utils/fileName';
+import GenerateTasksModal from './GenerateTasksModal';
+import PrdEditorBody from './PrdEditorBody';
+import PrdEditorFooter from './PrdEditorFooter';
+import PrdEditorHeader from './PrdEditorHeader';
+
+type PrdEditorWorkspaceProps = {
+  content: string;
+  onContentChange: (nextContent: string) => void;
+  fileName: string;
+  onFileNameChange: (nextFileName: string) => void;
+  isNewFile: boolean;
+  saving: boolean;
+  saveSuccess: boolean;
+  onSave: () => void;
+  onDownload: () => void;
+  onClose: () => void;
+  loadError: string | null;
+};
+
+export default function PrdEditorWorkspace({
+  content,
+  onContentChange,
+  fileName,
+  onFileNameChange,
+  isNewFile,
+  saving,
+  saveSuccess,
+  onSave,
+  onDownload,
+  onClose,
+  loadError,
+}: PrdEditorWorkspaceProps) {
+  const [isFullscreen, setIsFullscreen] = useState<boolean>(false);
+  const [isDarkMode, setIsDarkMode] = useState<boolean>(true);
+  const [previewMode, setPreviewMode] = useState<boolean>(false);
+  const [wordWrap, setWordWrap] = useState<boolean>(true);
+  const [showGenerateModal, setShowGenerateModal] = useState<boolean>(false);
+
+  const handleOpenGenerateTasks = () => {
+    if (!content.trim()) {
+      alert('Please add content to the PRD before generating tasks.');
+      return;
+    }
+
+    setShowGenerateModal(true);
+  };
+
+  return (
+    <div
+      className={cn(
+        'fixed inset-0 z-[200] md:bg-black/50 md:flex md:items-center md:justify-center',
+        isFullscreen ? 'md:p-0' : 'md:p-4',
+      )}
+    >
+      <div
+        className={cn(
+          'bg-white dark:bg-gray-900 shadow-2xl flex flex-col',
+          'w-full h-full md:rounded-lg md:shadow-2xl',
+          isFullscreen
+            ? 'md:w-full md:h-full md:rounded-none'
+            : 'md:w-full md:max-w-6xl md:h-[85vh] md:max-h-[85vh]',
+        )}
+      >
+        {loadError && (
+          <div className="px-4 py-3 border-b border-yellow-200 dark:border-yellow-800 bg-yellow-50 dark:bg-yellow-900/20 text-yellow-800 dark:text-yellow-200 text-sm">
+            {loadError}
+          </div>
+        )}
+
+        <PrdEditorHeader
+          fileName={fileName}
+          onFileNameChange={onFileNameChange}
+          isNewFile={isNewFile}
+          previewMode={previewMode}
+          onTogglePreview={() => setPreviewMode((current) => !current)}
+          wordWrap={wordWrap}
+          onToggleWordWrap={() => setWordWrap((current) => !current)}
+          isDarkMode={isDarkMode}
+          onToggleTheme={() => setIsDarkMode((current) => !current)}
+          onDownload={onDownload}
+          onOpenGenerateTasks={handleOpenGenerateTasks}
+          canGenerateTasks={Boolean(content.trim())}
+          onSave={onSave}
+          saving={saving}
+          saveSuccess={saveSuccess}
+          isFullscreen={isFullscreen}
+          onToggleFullscreen={() => setIsFullscreen((current) => !current)}
+          onClose={onClose}
+        />
+
+        <div className="flex-1 overflow-hidden">
+          <PrdEditorBody
+            content={content}
+            onContentChange={onContentChange}
+            previewMode={previewMode}
+            isDarkMode={isDarkMode}
+            wordWrap={wordWrap}
+          />
+        </div>
+
+        <PrdEditorFooter content={content} />
+      </div>
+
+      <GenerateTasksModal
+        isOpen={showGenerateModal}
+        fileName={ensurePrdExtension(fileName || 'prd')}
+        onClose={() => setShowGenerateModal(false)}
+      />
+    </div>
+  );
+}