"use client";

import React, { useState, useEffect, useRef } from 'react';
import { Image, FileText, Link, List, Plus } from 'lucide-react';
import { useRouter } from 'next/navigation';
import { useSession } from 'next-auth/react';
import { noteContentCache } from '@/lib/cache-utils';
import { HealthForm } from './health-form';

interface Note {
  id: string;
  title: string;
  content: string;
  lastModified: string;
  type: string;
  mime: string;
  etag: string;
}

interface EditorProps {
  note?: Note | null;
  onSave?: (note: Note) => void;
  currentFolder?: string;
  onRefresh?: () => void;
}

export const Editor: React.FC<EditorProps> = ({ note, onSave, currentFolder = 'Notes', onRefresh }) => {
  const [title, setTitle] = useState<string>(note?.title || '');
  const [content, setContent] = useState<string>(note?.content || '');
  const [isSaving, setIsSaving] = useState(false);
  const [isLoading, setIsLoading] = useState(false);
  const [error, setError] = useState<string | null>(null);
  const saveTimeout = useRef<NodeJS.Timeout>();
  const router = useRouter();
  const { data: session, status } = useSession();

  useEffect(() => {
    // Redirect to login if not authenticated
    if (status === 'unauthenticated') {
      router.push('/signin');
    }
  }, [status, router]);

  useEffect(() => {
    const fetchNoteContent = async () => {
      if (note?.id) {
        // If content is already provided (e.g., for mission files), use it directly
        if (note.content !== undefined && note.content !== '') {
          setContent(note.content);
          setIsLoading(false);
          return;
        }
        
        setIsLoading(true);
        setError(null);
        
        // Check cache first
        const cachedContent = noteContentCache.get<string>(note.id);
        if (cachedContent) {
          console.log(`Using cached content for note ${note.title}`);
          setContent(cachedContent);
          setIsLoading(false);
          return;
        }
        
        // For mission files, don't try to fetch via storage API
        if (note.id.startsWith('missions/')) {
          console.warn('Mission file content should be provided directly, not fetched');
          setIsLoading(false);
          return;
        }
        
        // If cache miss, fetch from API
        try {
          const response = await fetch(`/api/storage/files/content?path=${encodeURIComponent(note.id)}`);
          if (response.status === 401) {
            console.error('Authentication error, redirecting to login');
            router.push('/signin');
            return;
          }
          if (!response.ok) {
            const errorData = await response.json().catch(() => ({}));
            const errorMessage = errorData.message || errorData.error || `Failed to fetch note content: ${response.status}`;
            throw new Error(errorMessage);
          }
          const data = await response.json();
          setContent(data.content || '');
          
          // Update cache
          noteContentCache.set(note.id, data.content || '');
        } catch (error) {
          console.error('Error fetching note content:', error);
          const errorMessage = error instanceof Error ? error.message : 'Failed to load note content. Please try again later.';
          setError(errorMessage);
        } finally {
          setIsLoading(false);
        }
      }
    };

    if (note) {
      // For Diary and Health, if it's a new note (no id), set title to today's date
      if ((currentFolder === 'Diary' || currentFolder === 'Health') && !note.id) {
        const today = new Date();
        // Use French locale for date formatting: "16 janvier 2026"
        const dateStr = today.toLocaleDateString('fr-FR', { 
          day: 'numeric', 
          month: 'long', 
          year: 'numeric' 
        });
        setTitle(dateStr);
      } else {
        setTitle(note.title || '');
      }
      // Set content from note if provided, otherwise it will be fetched
      if (note.content !== undefined) {
        setContent(note.content);
      }
      if (note.id) {
        fetchNoteContent();
      } else {
        if (note.content === undefined) {
          setContent('');
        }
      }
    } else {
      setTitle('');
      setContent('');
    }
  }, [note, router, currentFolder]);

  const handleTitleChange = (e: React.ChangeEvent<HTMLInputElement>) => {
    setTitle(e.target.value);
    debouncedSave();
  };

  const handleContentChange = (e: React.ChangeEvent<HTMLTextAreaElement>) => {
    setContent(e.target.value);
    debouncedSave();
  };

  // Handle content change from HealthForm (direct string update)
  const handleHealthContentChange = (newContent: string) => {
    setContent(newContent);
    debouncedSave();
  };

  const debouncedSave = () => {
    if (saveTimeout.current) {
      clearTimeout(saveTimeout.current);
    }
    saveTimeout.current = setTimeout(() => {
      handleSave();
    }, 1000); // Save after 1 second of inactivity
  };

  const handleSave = async () => {
    if (!title || !content) return;
    if (!session) {
      console.error('No active session, cannot save');
      setError('You must be logged in to save notes');
      return;
    }
    
    // For Health folder, don't save if content is just empty JSON
    if (currentFolder === 'Health') {
      try {
        const parsed = JSON.parse(content);
        const isEmpty = Object.keys(parsed).length === 0 || (Object.keys(parsed).length === 1 && parsed.date);
        if (isEmpty) {
          return; // Don't save empty health forms
        }
      } catch {
        // If not valid JSON, continue with save
      }
    }
    
    setIsSaving(true);
    setError(null);
    try {
      // Construct the full note ID if it doesn't exist yet
      const noteId = note?.id || `user-${session.user.id}/${currentFolder.toLowerCase()}/${title}${title.endsWith('.md') ? '' : '.md'}`;
      
      const endpoint = '/api/storage/files';
      const method = note?.id ? 'PUT' : 'POST';
      
      console.log('Saving note:', {
        id: noteId,
        title,
        folder: currentFolder,
        contentLength: content.length
      });
      
      const response = await fetch(endpoint, {
        method,
        headers: {
          'Content-Type': 'application/json',
        },
        body: JSON.stringify({
          id: noteId,
          title,
          content,
          folder: currentFolder.toLowerCase()
        }),
      });

      if (response.status === 401) {
        console.error('Authentication error, redirecting to login');
        router.push('/signin');
        return;
      }

      if (!response.ok) {
        const errorData = await response.text();
        console.error('Failed to save note:', {
          status: response.status,
          statusText: response.statusText,
          data: errorData
        });
        setError(`Failed to save note: ${response.statusText}`);
        throw new Error(`Failed to save note: ${response.status} ${response.statusText}`);
      }

      const savedNote = await response.json();
      console.log('Note saved successfully:', savedNote);
      
      // Update content cache after successful save
      noteContentCache.set(noteId, content);
      
      setError(null);
      onSave?.({
        ...savedNote,
        content
      });
      // Note: onRefresh is called, but handleSaveNote already calls fetchNotes
      // So we don't need to call onRefresh here to avoid double fetch
      // onRefresh?.();
    } catch (error) {
      console.error('Error saving note:', error);
    } finally {
      setIsSaving(false);
    }
  };

  if (!session && status !== 'loading') {
    return (
      <div className="flex flex-col h-full bg-carnet-bg items-center justify-center">
        <div className="text-center">
          <h2 className="text-xl font-semibold text-carnet-text-primary mb-2">
            Authentication Required
          </h2>
          <p className="text-carnet-text-muted mb-4">
            Please log in to access your notes
          </p>
          <button 
            onClick={() => router.push('/signin')}
            className="px-4 py-2 bg-blue-500 text-white rounded hover:bg-blue-600"
          >
            Go to Login
          </button>
        </div>
      </div>
    );
  }

  if (!note) {
    return (
      <div className="flex flex-col h-full bg-carnet-bg items-center justify-center">
        <div className="text-center">
          <FileText className="h-12 w-12 text-carnet-text-muted mx-auto mb-4" />
          <h2 className="text-xl font-semibold text-carnet-text-primary mb-2">
            Sélectionnez une note
          </h2>
          <p className="text-carnet-text-muted">
            Choisissez une note existante ou créez-en une nouvelle
          </p>
        </div>
      </div>
    );
  }

  return (
    <div className="flex flex-col h-full bg-carnet-bg">
      {/* Title Bar */}
      <div className="p-4 border-b border-carnet-border">
        <input
          type="text"
          value={title ?? ''}
          onChange={handleTitleChange}
          placeholder="Titre"
          disabled={currentFolder === 'Diary' || currentFolder === 'Health'}
          className={`w-full text-xl font-semibold text-carnet-text-primary placeholder-carnet-text-muted focus:outline-none bg-transparent ${
            (currentFolder === 'Diary' || currentFolder === 'Health') ? 'opacity-60 cursor-not-allowed' : ''
          }`}
          title={currentFolder === 'Diary' || currentFolder === 'Health' ? 'Le titre est automatiquement la date du jour pour les journaux' : ''}
        />
      </div>

      {/* Error Display */}
      {error && (
        <div className="p-2 m-2 bg-red-100 border border-red-400 text-red-700 rounded">
          {error}
        </div>
      )}

      {/* Editor Area */}
      <div className="flex-1 overflow-y-auto">
        {isLoading ? (
          <div className="flex items-center justify-center h-full">
            <div className="animate-spin rounded-full h-8 w-8 border-t-2 border-b-2 border-primary"></div>
          </div>
        ) : currentFolder === 'Health' ? (
          // Use HealthForm for Health folder
          <HealthForm
            content={content}
            onContentChange={handleHealthContentChange}
            date={note?.lastModified}
          />
        ) : (
          <div className="p-4">
            <textarea
              value={content ?? ''}
              onChange={handleContentChange}
              placeholder="Ecrire..."
              className="w-full h-full resize-none focus:outline-none bg-transparent text-carnet-text-primary placeholder-carnet-text-muted"
              style={{ minHeight: '400px' }}
            />
          </div>
        )}
      </div>
      {isSaving && (
        <div className="absolute bottom-4 right-4 text-sm text-carnet-text-muted">
          Enregistrement...
        </div>
      )}
    </div>
  );
};