import React, { useCallback, useMemo, useState, useRef } from 'react';
import ReactMarkdown from 'react-markdown';
import remarkGfm from 'remark-gfm';
import { Check, Copy } from 'lucide-react';
function useCopy(timeoutMs = 900) {
    const [copied, setCopied] = useState(false);
    const copy = async (text) => {
        try {
            await navigator.clipboard.writeText(text);
            setCopied(true);
            window.setTimeout(() => setCopied(false), timeoutMs);
        }
        catch {
            // noop (clipboard may be blocked)
        }
    };
    return { copied, copy };
}
function languageFromClassName(className) {
    if (!className)
        return '';
    const m = /language-([a-z0-9_-]+)/i.exec(className);
    return m?.[1] ?? '';
}
/** Copy-enabled code block with language label */
function CodeBlock({ lang, raw }) {
    const { copied, copy } = useCopy();
    return (<div className="rounded-2xl border border-white/10 bg-black/35 overflow-hidden">
      <div className="flex items-center justify-between px-3 py-2 border-b border-white/10 bg-white/5">
        <div className="text-[11px] tracking-wide text-white/60">
          {lang ? lang.toUpperCase() : 'CODE'}
        </div>
        <button type="button" onClick={() => copy(raw)} className="inline-flex items-center gap-1.5 text-[11px] px-2 py-1 rounded-full bg-white/10 hover:bg-white/15 border border-white/10 hover:border-white/20 text-white/75 hover:text-white transition" title="Copy code">
          {copied ? <Check size={13}/> : <Copy size={13}/>}
          {copied ? 'Copied' : 'Copy'}
        </button>
      </div>
      <pre className="overflow-x-auto p-4">
        <code className="text-[13px] leading-relaxed">{raw}</code>
      </pre>
    </div>);
}
/** Image component with retry + visible error placeholder (no silent hiding). */
function MarkdownImage({ src, alt, rawSrc, onImageClick }) {
    const [state, setState] = useState('loading');
    const retryCount = useRef(0);
    const MAX_RETRIES = 2;
    const handleError = useCallback(() => {
        if (retryCount.current < MAX_RETRIES) {
            retryCount.current += 1;
            // Force re-fetch by appending a cache-bust param
            setState('loading');
        }
        else {
            setState('error');
        }
    }, []);
    if (state === 'error') {
        return (<div className="flex flex-col items-center gap-1.5 w-72 py-4 px-3 rounded-xl border border-white/10 bg-black/20 my-2 text-white/50 text-xs">
        <span>Image failed to load</span>
        {rawSrc && <span className="text-white/30 break-all text-[10px]">{rawSrc}</span>}
        <button type="button" onClick={() => { retryCount.current = 0; setState('loading'); }} className="mt-1 px-2 py-0.5 rounded bg-white/10 hover:bg-white/20 text-white/60 hover:text-white/80 transition text-[11px]">
          Retry
        </button>
      </div>);
    }
    // Append cache-bust on retries so browser re-fetches
    const finalSrc = retryCount.current > 0 && src
        ? `${src}${src.includes('?') ? '&' : '?'}_retry=${retryCount.current}`
        : src;
    return (<img src={finalSrc} alt={alt || 'Photo'} onClick={src ? () => onImageClick?.(src) : undefined} className="w-72 max-h-96 h-auto object-contain rounded-xl my-2 cursor-zoom-in hover:opacity-90 transition-opacity" loading="lazy" onLoad={() => setState('loaded')} onError={handleError}/>);
}
/**
 * Industry-grade Markdown renderer for assistant messages:
 * - GFM tables, task lists, etc.
 * - Safe by default (no raw HTML).
 * - Code blocks have header + language + copy button.
 */
export function MessageMarkdown({ text, onImageClick, backendUrl }) {
    const normalized = useMemo(() => {
        let t = (text ?? '').replace(/\r\n/g, '\n');
        // Fix LLM-wrapped URLs: strip whitespace inside markdown image/link URLs
        // e.g. ![alt](http://host/path/ with-space) → ![alt](http://host/path/with-space)
        t = t.replace(/(!?\[[^\]]*\]\()([^)]+)\)/g, (_m, prefix, url) => `${prefix}${url.replace(/\s+/g, '')})`);
        return t;
    }, [text]);
    /** Resolve backend-relative image paths (e.g. /comfy/view/..., /files/...) to full URLs.
     *  Appends auth token for /files/ paths that require authentication. */
    const resolveImgSrc = useCallback((src) => {
        if (!src)
            return src;
        // Strip whitespace LLMs may inject mid-URL when line-wrapping
        src = src.replace(/\s+/g, '');
        // Resolve media:// refs via backend /media/resolve endpoint
        if (src.startsWith('media://') && backendUrl) {
            const tok = localStorage.getItem('homepilot_auth_token') || '';
            const base = backendUrl.replace(/\/+$/, '');
            const qp = tok ? `&token=${encodeURIComponent(tok)}` : '';
            // Pass current project_id as fallback so malformed LLM refs
            // (e.g. media://persona_1) can still resolve to the correct avatar
            const pid = localStorage.getItem('homepilot_current_project') || '';
            const pidParam = pid ? `&project_id=${encodeURIComponent(pid)}` : '';
            return `${base}/media/resolve?ref=${encodeURIComponent(src)}${qp}${pidParam}`;
        }
        if (src.startsWith('http://') || src.startsWith('https://') || src.startsWith('data:') || src.startsWith('blob:')) {
            // For absolute backend URLs that contain /files/, append token
            if (backendUrl && src.includes('/files/')) {
                const tok = localStorage.getItem('homepilot_auth_token') || '';
                if (tok) {
                    const sep = src.includes('?') ? '&' : '?';
                    return `${src}${sep}token=${encodeURIComponent(tok)}`;
                }
            }
            return src;
        }
        if (backendUrl) {
            const base = backendUrl.replace(/\/+$/, '');
            const path = src.startsWith('/') ? src : `/${src}`;
            const full = `${base}${path}`;
            // Append token for /files/ paths
            if (path.startsWith('/files/')) {
                const tok = localStorage.getItem('homepilot_auth_token') || '';
                if (tok) {
                    const sep = full.includes('?') ? '&' : '?';
                    return `${full}${sep}token=${encodeURIComponent(tok)}`;
                }
            }
            return full;
        }
        return src;
    }, [backendUrl]);
    // Memoize the components object so ReactMarkdown doesn't remount
    // custom elements (especially <img>) on every parent re-render.
    const mdComponents = useMemo(() => ({
        a: ({ children, href, ...props }) => (<a {...props} href={href} target="_blank" rel="noreferrer" className="underline decoration-white/30 hover:decoration-white/70 text-white">
        {children}
      </a>),
        code: ({ children, className }) => {
            const isBlock = !!className;
            const lang = languageFromClassName(className);
            const raw = String(children ?? '').replace(/\n$/, '');
            if (!isBlock) {
                return (<code className="px-1.5 py-0.5 rounded-md bg-white/10 border border-white/10 text-[0.95em]">
            {children}
          </code>);
            }
            return <CodeBlock lang={lang} raw={raw}/>;
        },
        h1: ({ children }) => <h1 className="text-xl font-semibold mt-3 mb-2">{children}</h1>,
        h2: ({ children }) => <h2 className="text-lg font-semibold mt-3 mb-2">{children}</h2>,
        h3: ({ children }) => <h3 className="text-base font-semibold mt-3 mb-2">{children}</h3>,
        ul: ({ children }) => <ul className="list-disc pl-5 space-y-1">{children}</ul>,
        ol: ({ children }) => <ol className="list-decimal pl-5 space-y-1">{children}</ol>,
        li: ({ children }) => <li className="leading-relaxed">{children}</li>,
        blockquote: ({ children }) => (<blockquote className="border-l-2 border-white/15 pl-4 italic text-white/90">{children}</blockquote>),
        table: ({ children }) => (<div className="overflow-x-auto rounded-2xl border border-white/10">
        <table className="w-full text-sm">{children}</table>
      </div>),
        thead: ({ children }) => <thead className="bg-white/5">{children}</thead>,
        th: ({ children }) => <th className="text-left px-3 py-2 font-semibold">{children}</th>,
        td: ({ children }) => <td className="px-3 py-2 border-t border-white/10">{children}</td>,
        img: ({ src, alt }) => {
            const resolved = resolveImgSrc(src);
            return <MarkdownImage src={resolved} alt={alt} rawSrc={src} onImageClick={onImageClick}/>;
        },
        p: ({ children }) => <p className="leading-relaxed">{children}</p>,
    }), [resolveImgSrc, onImageClick]);
    return (<div className="prose prose-invert max-w-none prose-p:my-2 prose-pre:my-2 prose-ul:my-2 prose-ol:my-2 prose-li:my-1 prose-hr:my-4 prose-blockquote:my-3">
      <ReactMarkdown remarkPlugins={[remarkGfm]} components={mdComponents}>
        {normalized}
      </ReactMarkdown>
    </div>);
}