import { forwardRef, useEffect, useImperativeHandle, useRef } from 'react'
import { EditorContent, useEditor, useEditorState } from '@tiptap/react'
import StarterKit from '@tiptap/starter-kit'
import Placeholder from '@tiptap/extension-placeholder'
import { docToMarkdown, markdownToDoc, unplacedMedia } from '../journal/document.js'
import { JournalMediaContext, KanshoMedia } from '../journal/KanshoMedia.jsx'

function ToolbarButton({ active, children, disabled, onClick }) {
  return (
    <button type="button" className={active ? 'ghost active' : 'ghost'} disabled={disabled} onClick={onClick}>
      {children}
    </button>
  )
}

const JournalDocumentEditor = forwardRef(function JournalDocumentEditor(
  { body, contentKey, onChange, media, previews, onUpload, onPlaced, onRemoveMedia, disabled },
  ref
) {
  const imageInput = useRef(null)
  const videoInput = useRef(null)
  const editorRef = useRef(null)

  const editor = useEditor({
    immediatelyRender: false,
    shouldRerenderOnTransaction: true,
    editable: !disabled,
    extensions: [
      StarterKit.configure({
        code: false,
        codeBlock: false,
        blockquote: false,
        link: false,
        horizontalRule: false,
        heading: { levels: [2, 3] }
      }),
      Placeholder.configure({ placeholder: 'Schreiben …' }),
      KanshoMedia
    ],
    content: '',
    onUpdate: ({ editor: instance }) => {
      onChange(docToMarkdown(instance.getJSON()))
    }
  })

  editorRef.current = editor

  useImperativeHandle(ref, () => ({
    getMarkdown: () => {
      const instance = editorRef.current
      if (!instance) return body || ''
      return docToMarkdown(instance.getJSON())
    }
  }), [body])

  useEffect(() => {
    if (!editor) return
    editor.setEditable(!disabled)
  }, [editor, disabled])

  useEffect(() => {
    if (!editor) return
    editor.commands.setContent(markdownToDoc(body || ''), { emitUpdate: false })
  }, [editor, contentKey])

  const marks = useEditorState({
    editor,
    selector: ({ editor: instance }) =>
      instance
        ? {
            paragraph: instance.isActive('paragraph'),
            heading: instance.isActive('heading', { level: 2 }),
            subheading: instance.isActive('heading', { level: 3 }),
            bold: instance.isActive('bold'),
            italic: instance.isActive('italic'),
            underline: instance.isActive('underline'),
            bullet: instance.isActive('bulletList'),
            ordered: instance.isActive('orderedList')
          }
        : {}
  })

  const insertFile = async (event) => {
    const file = event.target.files?.[0]
    event.target.value = ''
    if (!file || !editor) return
    const asset = await onUpload(file)
    if (!asset?.id) return
    editor.chain().focus().insertKanshoMedia({
      id: asset.id,
      caption: '',
      kind: asset.kind || (file.type.startsWith('video/') ? 'video' : 'image')
    }).run()
    await onPlaced?.()
  }

  const insertExisting = async (item) => {
    if (!editor) return
    editor.chain().focus().insertKanshoMedia({
      id: item.id,
      caption: '',
      kind: item.kind || 'image'
    }).run()
    await onPlaced?.()
  }

  const unused = unplacedMedia(editor ? docToMarkdown(editor.getJSON()) : body, media)

  return (
    <JournalMediaContext.Provider value={{ previews, media, onRemoveMedia }}>
      <div className="journal-doc">
        <div className="journal-toolbar" role="toolbar" aria-label="Textformat">
          <ToolbarButton
            disabled={disabled || !editor}
            active={marks?.paragraph}
            onClick={() => editor.chain().focus().setParagraph().run()}
          >
            Absatz
          </ToolbarButton>
          <ToolbarButton
            disabled={disabled || !editor}
            active={marks?.heading}
            onClick={() => editor.chain().focus().toggleHeading({ level: 2 }).run()}
          >
            Überschrift
          </ToolbarButton>
          <ToolbarButton
            disabled={disabled || !editor}
            active={marks?.subheading}
            onClick={() => editor.chain().focus().toggleHeading({ level: 3 }).run()}
          >
            Zwischenüberschrift
          </ToolbarButton>
          <ToolbarButton
            disabled={disabled || !editor}
            active={marks?.bold}
            onClick={() => editor.chain().focus().toggleBold().run()}
          >
            Fett
          </ToolbarButton>
          <ToolbarButton
            disabled={disabled || !editor}
            active={marks?.italic}
            onClick={() => editor.chain().focus().toggleItalic().run()}
          >
            Kursiv
          </ToolbarButton>
          <ToolbarButton
            disabled={disabled || !editor}
            active={marks?.underline}
            onClick={() => editor.chain().focus().toggleUnderline().run()}
          >
            Unterstrichen
          </ToolbarButton>
          <ToolbarButton
            disabled={disabled || !editor}
            active={marks?.bullet}
            onClick={() => editor.chain().focus().toggleBulletList().run()}
          >
            Liste
          </ToolbarButton>
          <ToolbarButton
            disabled={disabled || !editor}
            active={marks?.ordered}
            onClick={() => editor.chain().focus().toggleOrderedList().run()}
          >
            Nummerierung
          </ToolbarButton>
          <ToolbarButton disabled={disabled || !editor} onClick={() => imageInput.current?.click()}>
            Bild
          </ToolbarButton>
          <ToolbarButton disabled={disabled || !editor} onClick={() => videoInput.current?.click()}>
            Video
          </ToolbarButton>
          <input
            ref={imageInput}
            className="visually-hidden"
            type="file"
            accept="image/jpeg,image/png,image/gif,image/webp"
            onChange={insertFile}
          />
          <input
            ref={videoInput}
            className="visually-hidden"
            type="file"
            accept="video/mp4,video/webm,video/quicktime"
            onChange={insertFile}
          />
        </div>
        <div className={`journal-flow ${disabled ? 'disabled' : ''}`}>
          <EditorContent editor={editor} />
        </div>
        {unused.length > 0 && (
          <div className="journal-unplaced">
            <p className="muted">Hochgeladen, aber nicht im Text. Dieselbe Datei mehrfach zu wählen erzeugt mehrere Uploads — im Text duplizieren, statt erneut hochzuladen.</p>
            <ul className="stack">
              {unused.map((item) => (
                <li key={item.id} className="row-item">
                <span>{item.filename || item.kind} · {String(item.id).slice(0, 8)}</span>
                <span className="row-actions">
                  <button type="button" className="ghost" disabled={disabled} onClick={() => insertExisting(item)}>
                    Hier einfügen
                  </button>
                  <button
                    type="button"
                    className="ghost"
                    disabled={disabled}
                    onClick={() => onRemoveMedia?.(item.id)}
                  >
                    Verwerfen
                  </button>
                </span>
                </li>
              ))}
            </ul>
          </div>
        )}
      </div>
    </JournalMediaContext.Provider>
  )
})

export default JournalDocumentEditor