import React, { useRef, useState, useCallback } from 'react';
import Image from 'next/image';
import { ArrowDown, CircleDashed } from 'lucide-react';
import { Button } from '@/components/ui/button';
import { Markdown } from '@/components/ui/markdown';
import { UnifiedMessage, ParsedContent, ParsedMetadata } from '@/components/thread/types';
import { safeJsonParse } from '@/components/thread/utils';
import { FileAttachmentGrid } from '@/components/thread/file-attachment';

// Define the set of tags whose raw XML should be hidden during streaming
const HIDE_STREAMING_XML_TAGS = new Set([
    'execute-command',
    'create-file',
    'delete-file',
    'full-file-rewrite',
    'str-replace',
    'browser-click-element',
    'browser-close-tab',
    'browser-drag-drop',
    'browser-get-dropdown-options',
    'browser-go-back',
    'browser-input-text',
    'browser-navigate-to',
    'browser-scroll-down',
    'browser-scroll-to-text',
    'browser-scroll-up',
    'browser-select-dropdown-option',
    'browser-send-keys',
    'browser-switch-tab',
    'browser-wait',
    'deploy',
    'ask',
    'complete',
    'crawl-webpage',
    'web-search'
]);

// Helper function to render attachments
export function renderAttachments(attachments: string[], fileViewerHandler?: (filePath?: string) => void, sandboxId?: string) {
    if (!attachments || attachments.length === 0) return null;
    return <FileAttachmentGrid
        attachments={attachments}
        onFileClick={fileViewerHandler}
        showPreviews={true}
        sandboxId={sandboxId}
    />;
}

// Render Markdown content while preserving XML tags that should be displayed as tool calls
export function renderMarkdownContent(
    content: string,
    handleToolClick: (assistantMessageId: string | null, toolName: string) => void,
    messageId: string | null,
    fileViewerHandler?: (filePath?: string) => void,
    sandboxId?: string
) {
    const xmlRegex = /<(?!inform\b)([a-zA-Z\-_]+)(?:\s+[^>]*)?>(?:[\s\S]*?)<\/\1>|<(?!inform\b)([a-zA-Z\-_]+)(?:\s+[^>]*)?\/>/g;
    let lastIndex = 0;
    const contentParts: React.ReactNode[] = [];
    let match;

    // If no XML tags found, just return the full content as markdown
    if (!content.match(xmlRegex)) {
        return <Markdown className="text-sm prose prose-sm dark:prose-invert chat-markdown max-w-none break-words">{content}</Markdown>;
    }

    while ((match = xmlRegex.exec(content)) !== null) {
        // Add text before the tag as markdown
        if (match.index > lastIndex) {
            const textBeforeTag = content.substring(lastIndex, match.index);
            contentParts.push(
                <Markdown key={`md-${lastIndex}`} className="text-sm prose prose-sm dark:prose-invert chat-markdown max-w-none inline-block mr-1 break-words">{textBeforeTag}</Markdown>
            );
        }

        const rawXml = match[0];
        const toolName = match[1] || match[2];
        const toolCallKey = `tool-${match.index}`;

        if (toolName === 'ask') {
            // Extract attachments from the XML attributes
            const attachmentsMatch = rawXml.match(/attachments=["']([^"']*)["']/i);
            const attachments = attachmentsMatch
                ? attachmentsMatch[1].split(',').map(a => a.trim())
                : [];

            // Extract content from the ask tag
            const contentMatch = rawXml.match(/<ask[^>]*>([\s\S]*?)<\/ask>/i);
            const askContent = contentMatch ? contentMatch[1] : '';

            // Render <ask> tag content with attachment UI (using the helper)
            contentParts.push(
                <div key={`ask-${match.index}`} className="space-y-3">
                    <Markdown className="text-sm prose prose-sm dark:prose-invert chat-markdown max-w-none break-words [&>:first-child]:mt-0 prose-headings:mt-3">{askContent}</Markdown>
                    {renderAttachments(attachments, fileViewerHandler, sandboxId)}
                </div>
            );
        } else {
            // Import dynamically to avoid circular dependencies
            const { getToolIcon, extractPrimaryParam } = require('@/components/thread/utils');
            const IconComponent = getToolIcon(toolName);
            const paramDisplay = extractPrimaryParam(toolName, rawXml);

            // Render tool button as a clickable element
            contentParts.push(
                <button
                    key={toolCallKey}
                    onClick={() => handleToolClick(messageId, toolName)}
                    className="inline-flex items-center gap-1.5 py-1 px-2.5 my-1 text-xs text-muted-foreground bg-muted hover:bg-muted/80 rounded-md transition-colors cursor-pointer border border-border"
                >
                    <IconComponent className="h-3.5 w-3.5 text-muted-foreground flex-shrink-0" />
                    <span className="font-mono text-xs text-foreground">{toolName}</span>
                    {paramDisplay && <span className="ml-1 text-muted-foreground truncate max-w-[200px]" title={paramDisplay}>{paramDisplay}</span>}
                </button>
            );
        }
        lastIndex = xmlRegex.lastIndex;
    }

    // Add text after the last tag
    if (lastIndex < content.length) {
        contentParts.push(
            <Markdown key={`md-${lastIndex}`} className="text-sm prose prose-sm dark:prose-invert chat-markdown max-w-none break-words">{content.substring(lastIndex)}</Markdown>
        );
    }

    return contentParts;
}

export interface ThreadContentProps {
    messages: UnifiedMessage[];
    streamingTextContent?: string;
    streamingToolCall?: any;
    agentStatus: 'idle' | 'running' | 'connecting' | 'error';
    handleToolClick: (assistantMessageId: string | null, toolName: string) => void;
    handleOpenFileViewer: (filePath?: string) => void;
    readOnly?: boolean;
    visibleMessages?: UnifiedMessage[]; // For playback mode
    streamingText?: string; // For playback mode
    isStreamingText?: boolean; // For playback mode
    currentToolCall?: any; // For playback mode
    streamHookStatus?: string; // Add this prop
    sandboxId?: string; // Add sandboxId prop
}

export const ThreadContent: React.FC<ThreadContentProps> = ({
    messages,
    streamingTextContent = "",
    streamingToolCall,
    agentStatus,
    handleToolClick,
    handleOpenFileViewer,
    readOnly = false,
    visibleMessages,
    streamingText = "",
    isStreamingText = false,
    currentToolCall,
    streamHookStatus = "idle",
    sandboxId
}) => {
    const messagesEndRef = useRef<HTMLDivElement>(null);
    const messagesContainerRef = useRef<HTMLDivElement>(null);
    const latestMessageRef = useRef<HTMLDivElement>(null);
    const [showScrollButton, setShowScrollButton] = useState(false);
    const [userHasScrolled, setUserHasScrolled] = useState(false);

    // In playback mode, we use visibleMessages instead of messages
    const displayMessages = readOnly && visibleMessages ? visibleMessages : messages;

    const handleScroll = () => {
        if (!messagesContainerRef.current) return;
        const { scrollTop, scrollHeight, clientHeight } = messagesContainerRef.current;
        const isScrolledUp = scrollHeight - scrollTop - clientHeight > 100;
        setShowScrollButton(isScrolledUp);
        setUserHasScrolled(isScrolledUp);
    };

    const scrollToBottom = useCallback((behavior: ScrollBehavior = 'smooth') => {
        messagesEndRef.current?.scrollIntoView({ behavior });
    }, []);

    return (
        <>
            <div
                ref={messagesContainerRef}
                className="flex-1 overflow-y-auto px-6 py-4 pb-24 bg-background/95 backdrop-blur supports-[backdrop-filter]:bg-background/60"
                onScroll={handleScroll}
            >
                <div className="mx-auto max-w-3xl">
                    {displayMessages.length === 0 && !streamingTextContent && !streamingToolCall &&
                        !streamingText && !currentToolCall && agentStatus === 'idle' ? (
                        <div className="flex h-full items-center justify-center">
                            <div className="text-center text-muted-foreground">
                                {readOnly ? "No messages to display." : "Send a message to start."}
                            </div>
                        </div>
                    ) : (
                        <div className="space-y-8">
                            {(() => {
                                // Group messages logic
                                type MessageGroup = {
                                    type: 'user' | 'assistant_group';
                                    messages: UnifiedMessage[];
                                    key: string;
                                };
                                const groupedMessages: MessageGroup[] = [];
                                let currentGroup: MessageGroup | null = null;

                                displayMessages.forEach((message, index) => {
                                    const messageType = message.type;
                                    const key = message.message_id || `msg-${index}`;

                                    if (messageType === 'user') {
                                        if (currentGroup) {
                                            groupedMessages.push(currentGroup);
                                        }
                                        groupedMessages.push({ type: 'user', messages: [message], key });
                                        currentGroup = null;
                                    } else if (messageType === 'assistant' || messageType === 'tool' || messageType === 'browser_state') {
                                        if (currentGroup && currentGroup.type === 'assistant_group') {
                                            currentGroup.messages.push(message);
                                        } else {
                                            if (currentGroup) {
                                                groupedMessages.push(currentGroup);
                                            }
                                            currentGroup = { type: 'assistant_group', messages: [message], key };
                                        }
                                    } else if (messageType !== 'status') {
                                        if (currentGroup) {
                                            groupedMessages.push(currentGroup);
                                            currentGroup = null;
                                        }
                                    }
                                });

                                if (currentGroup) {
                                    groupedMessages.push(currentGroup);
                                }

                                return groupedMessages.map((group, groupIndex) => {
                                    if (group.type === 'user') {
                                        const message = group.messages[0];
                                        const messageContent = (() => {
                                            try {
                                                const parsed = safeJsonParse<ParsedContent>(message.content, { content: message.content });
                                                return parsed.content || message.content;
                                            } catch {
                                                return message.content;
                                            }
                                        })();

                                        // Extract attachments from the message content
                                        const attachmentsMatch = messageContent.match(/\[Uploaded File: (.*?)\]/g);
                                        const attachments = attachmentsMatch
                                            ? attachmentsMatch.map(match => {
                                                const pathMatch = match.match(/\[Uploaded File: (.*?)\]/);
                                                return pathMatch ? pathMatch[1] : null;
                                            }).filter(Boolean)
                                            : [];

                                        // Remove attachment info from the message content
                                        const cleanContent = messageContent.replace(/\[Uploaded File: .*?\]/g, '').trim();

                                        return (
                                            <div key={group.key} className="flex justify-end">
                                                <div className="inline-flex max-w-[85%] rounded-lg bg-primary/10 px-4 py-3">
                                                    <div className="space-y-3">
                                                        {cleanContent && (
                                                            <Markdown className="text-sm prose prose-sm dark:prose-invert chat-markdown max-w-none [&>:first-child]:mt-0 prose-headings:mt-3">{cleanContent}</Markdown>
                                                        )}

                                                        {/* Use the helper function to render user attachments */}
                                                        {renderAttachments(attachments as string[], handleOpenFileViewer, sandboxId)}
                                                    </div>
                                                </div>
                                            </div>
                                        );
                                    } else if (group.type === 'assistant_group') {
                                        return (
                                            <div key={group.key} ref={groupIndex === groupedMessages.length - 1 ? latestMessageRef : null}>
                                                <div className="flex items-start gap-3">
                                                    <div className="flex-shrink-0 w-5 h-5 mt-2 rounded-md flex items-center justify-center overflow-hidden ml-auto mr-2">
                                                        <Image src="/kortix-symbol.svg" alt="Kortix" width={14} height={14} className="object-contain invert dark:invert-0 opacity-70" />
                                                    </div>
                                                    <div className="flex-1">
                                                        <div className="inline-flex max-w-[90%] rounded-lg bg-muted/5 px-4 py-3 text-sm">
                                                            <div className="space-y-2">
                                                                {(() => {
                                                                    const toolResultsMap = new Map<string | null, UnifiedMessage[]>();
                                                                    group.messages.forEach(msg => {
                                                                        if (msg.type === 'tool') {
                                                                            const meta = safeJsonParse<ParsedMetadata>(msg.metadata, {});
                                                                            const assistantId = meta.assistant_message_id || null;
                                                                            if (!toolResultsMap.has(assistantId)) {
                                                                                toolResultsMap.set(assistantId, []);
                                                                            }
                                                                            toolResultsMap.get(assistantId)?.push(msg);
                                                                        }
                                                                    });

                                                                    const renderedToolResultIds = new Set<string>();
                                                                    const elements: React.ReactNode[] = [];

                                                                    group.messages.forEach((message, msgIndex) => {
                                                                        if (message.type === 'assistant') {
                                                                            const parsedContent = safeJsonParse<ParsedContent>(message.content, {});
                                                                            const msgKey = message.message_id || `submsg-assistant-${msgIndex}`;

                                                                            if (!parsedContent.content) return;

                                                                            const renderedContent = renderMarkdownContent(
                                                                                parsedContent.content,
                                                                                handleToolClick,
                                                                                message.message_id,
                                                                                handleOpenFileViewer,
                                                                                sandboxId
                                                                            );

                                                                            elements.push(
                                                                                <div key={msgKey} className={msgIndex > 0 ? "mt-2" : ""}>
                                                                                    <div className="prose prose-sm dark:prose-invert chat-markdown max-w-none [&>:first-child]:mt-0 prose-headings:mt-3">
                                                                                        {renderedContent}
                                                                                    </div>
                                                                                </div>
                                                                            );
                                                                        }
                                                                    });

                                                                    return elements;
                                                                })()}

                                                                {groupIndex === groupedMessages.length - 1 && !readOnly && (streamHookStatus === 'streaming' || streamHookStatus === 'connecting') && (
                                                                    <div className="mt-2">
                                                                        {(() => {
                                                                            let detectedTag: string | null = null;
                                                                            let tagStartIndex = -1;
                                                                            if (streamingTextContent) {
                                                                                for (const tag of HIDE_STREAMING_XML_TAGS) {
                                                                                    const openingTagPattern = `<${tag}`;
                                                                                    const index = streamingTextContent.indexOf(openingTagPattern);
                                                                                    if (index !== -1) {
                                                                                        detectedTag = tag;
                                                                                        tagStartIndex = index;
                                                                                        break;
                                                                                    }
                                                                                }
                                                                            }

                                                                            const textToRender = streamingTextContent || '';
                                                                            const textBeforeTag = detectedTag ? textToRender.substring(0, tagStartIndex) : textToRender;
                                                                            const showCursor = (streamHookStatus === 'streaming' || streamHookStatus === 'connecting') && !detectedTag;

                                                                            return (
                                                                                <>
                                                                                    {textBeforeTag && (
                                                                                        <Markdown className="text-sm prose prose-sm dark:prose-invert chat-markdown max-w-none [&>:first-child]:mt-0 prose-headings:mt-3">{textBeforeTag}</Markdown>
                                                                                    )}
                                                                                    {showCursor && (
                                                                                        <span className="inline-block h-4 w-0.5 bg-primary ml-0.5 -mb-1 animate-pulse" />
                                                                                    )}

                                                                                    {detectedTag && (
                                                                                        <div className="mt-2 mb-1">
                                                                                            <button
                                                                                                className="inline-flex items-center gap-1.5 py-1 px-2.5 text-xs font-medium text-primary bg-primary/10 hover:bg-primary/20 rounded-md transition-colors cursor-pointer border border-primary/20"
                                                                                            >
                                                                                                <CircleDashed className="h-3.5 w-3.5 text-primary flex-shrink-0 animate-spin animation-duration-2000" />
                                                                                                <span className="font-mono text-xs text-primary">{detectedTag}</span>
                                                                                            </button>
                                                                                        </div>
                                                                                    )}

                                                                                    {streamingToolCall && !detectedTag && (
                                                                                        <div className="mt-2 mb-1">
                                                                                            {(() => {
                                                                                                // Import dynamically to avoid circular dependencies
                                                                                                const { getToolIcon, extractPrimaryParam } = require('@/components/thread/utils');
                                                                                                const toolName = streamingToolCall.name || streamingToolCall.xml_tag_name || 'Tool';
                                                                                                const IconComponent = getToolIcon(toolName);
                                                                                                const paramDisplay = extractPrimaryParam(toolName, streamingToolCall.arguments || '');
                                                                                                return (
                                                                                                    <button
                                                                                                        className="inline-flex items-center gap-1.5 py-1 px-2.5 text-xs font-medium text-primary bg-primary/10 hover:bg-primary/20 rounded-md transition-colors cursor-pointer border border-primary/20"
                                                                                                    >
                                                                                                        <CircleDashed className="h-3.5 w-3.5 text-primary flex-shrink-0 animate-spin animation-duration-2000" />
                                                                                                        <span className="font-mono text-xs text-primary">{toolName}</span>
                                                                                                        {paramDisplay && <span className="ml-1 text-primary/70 truncate max-w-[200px]" title={paramDisplay}>{paramDisplay}</span>}
                                                                                                    </button>
                                                                                                );
                                                                                            })()}
                                                                                        </div>
                                                                                    )}
                                                                                </>
                                                                            );
                                                                        })()}
                                                                    </div>
                                                                )}

                                                                {/* For playback mode, show streaming text and tool calls */}
                                                                {readOnly && groupIndex === groupedMessages.length - 1 && isStreamingText && (
                                                                    <div className="mt-2">
                                                                        {(() => {
                                                                            let detectedTag: string | null = null;
                                                                            let tagStartIndex = -1;
                                                                            if (streamingText) {
                                                                                for (const tag of HIDE_STREAMING_XML_TAGS) {
                                                                                    const openingTagPattern = `<${tag}`;
                                                                                    const index = streamingText.indexOf(openingTagPattern);
                                                                                    if (index !== -1) {
                                                                                        detectedTag = tag;
                                                                                        tagStartIndex = index;
                                                                                        break;
                                                                                    }
                                                                                }
                                                                            }

                                                                            const textToRender = streamingText || '';
                                                                            const textBeforeTag = detectedTag ? textToRender.substring(0, tagStartIndex) : textToRender;
                                                                            const showCursor = isStreamingText && !detectedTag;

                                                                            return (
                                                                                <>
                                                                                    {textBeforeTag && (
                                                                                        <Markdown className="text-sm prose prose-sm dark:prose-invert chat-markdown max-w-none [&>:first-child]:mt-0 prose-headings:mt-3">{textBeforeTag}</Markdown>
                                                                                    )}
                                                                                    {showCursor && (
                                                                                        <span className="inline-block h-4 w-0.5 bg-primary ml-0.5 -mb-1 animate-pulse" />
                                                                                    )}

                                                                                    {detectedTag && (
                                                                                        <div className="mt-2 mb-1">
                                                                                            <button
                                                                                                className="inline-flex items-center gap-1.5 py-1 px-2.5 text-xs font-medium text-primary bg-primary/10 hover:bg-primary/20 rounded-md transition-colors cursor-pointer border border-primary/20"
                                                                                            >
                                                                                                <CircleDashed className="h-3.5 w-3.5 text-primary flex-shrink-0 animate-spin animation-duration-2000" />
                                                                                                <span className="font-mono text-xs text-primary">{detectedTag}</span>
                                                                                            </button>
                                                                                        </div>
                                                                                    )}
                                                                                </>
                                                                            );
                                                                        })()}
                                                                    </div>
                                                                )}
                                                            </div>
                                                        </div>
                                                    </div>
                                                </div>
                                            </div>
                                        );
                                    }
                                    return null;
                                });
                            })()}
                            {(agentStatus === 'running' || agentStatus === 'connecting') &&
                                !readOnly &&
                                (messages.length === 0 || messages[messages.length - 1].type === 'user') && (
                                    <div ref={latestMessageRef}>
                                        <div className="flex items-start gap-3">
                                            <div className="flex-shrink-0 w-5 h-5 rounded-md flex items-center justify-center overflow-hidden bg-primary/10">
                                                <Image src="/kortix-symbol.svg" alt="Suna" width={14} height={14} className="object-contain" />
                                            </div>
                                            <div className="flex-1 space-y-2">
                                                <div className="max-w-[90%] px-4 py-3 text-sm">
                                                    <div className="flex items-center gap-1.5 py-1">
                                                        <div className="h-1.5 w-1.5 rounded-full bg-primary/50 animate-pulse" />
                                                        <div className="h-1.5 w-1.5 rounded-full bg-primary/50 animate-pulse delay-150" />
                                                        <div className="h-1.5 w-1.5 rounded-full bg-primary/50 animate-pulse delay-300" />
                                                    </div>
                                                </div>
                                            </div>
                                        </div>
                                    </div>
                                )}

                            {/* For playback mode - Show tool call animation if active */}
                            {readOnly && currentToolCall && (
                                <div ref={latestMessageRef}>
                                    <div className="flex items-start gap-3">
                                        <div className="flex-shrink-0 w-5 h-5 mt-2 rounded-md flex items-center justify-center overflow-hidden bg-primary/10">
                                            <Image src="/kortix-symbol.svg" alt="Suna" width={14} height={14} className="object-contain" />
                                        </div>
                                        <div className="flex-1 space-y-2">
                                            <div className="inline-flex items-center gap-1.5 py-1.5 px-3 text-xs font-medium text-primary bg-primary/10 rounded-md border border-primary/20">
                                                <CircleDashed className="h-3.5 w-3.5 text-primary flex-shrink-0 animate-spin animation-duration-2000" />
                                                <span className="font-mono text-xs text-primary">
                                                    {currentToolCall.name || 'Using Tool'}
                                                </span>
                                            </div>
                                        </div>
                                    </div>
                                </div>
                            )}

                            {/* For playback mode - Show streaming indicator if no messages yet */}
                            {readOnly && visibleMessages && visibleMessages.length === 0 && isStreamingText && (
                                <div ref={latestMessageRef}>
                                    <div className="flex items-start gap-3">
                                        <div className="flex-shrink-0 w-5 h-5 mt-2 rounded-md flex items-center justify-center overflow-hidden bg-primary/10">
                                            <Image src="/kortix-symbol.svg" alt="Suna" width={14} height={14} className="object-contain" />
                                        </div>
                                        <div className="flex-1 space-y-2">
                                            <div className="max-w-[90%] px-4 py-3 text-sm">
                                                <div className="flex items-center gap-1.5 py-1">
                                                    <div className="h-1.5 w-1.5 rounded-full bg-primary/50 animate-pulse" />
                                                    <div className="h-1.5 w-1.5 rounded-full bg-primary/50 animate-pulse delay-150" />
                                                    <div className="h-1.5 w-1.5 rounded-full bg-primary/50 animate-pulse delay-300" />
                                                </div>
                                            </div>
                                        </div>
                                    </div>
                                </div>
                            )}
                        </div>
                    )}
                    <div ref={messagesEndRef} className="h-1" />
                </div>
            </div>

            {/* Scroll to bottom button */}
            {showScrollButton && (
                <Button
                    variant="outline"
                    size="icon"
                    className="fixed bottom-20 right-6 z-10 h-8 w-8 rounded-full shadow-md"
                    onClick={() => scrollToBottom('smooth')}
                >
                    <ArrowDown className="h-4 w-4" />
                </Button>
            )}
        </>
    );
};

export default ThreadContent;