import React, { useState, useEffect } from "react";

const ChatBox = ({ activeThread }) => {
  const [messages, setMessages] = useState([]);
  const [userInput, setUserInput] = useState("");
  const [isStreaming, setIsStreaming] = useState(false);

  const FLASK_API_URL = process.env.FLASK_API_URL;

  // useEffect(() => {
  //   // Fetch existing messages for the active thread
  //   fetch(`http://127.0.0.1:5000/api/chat/${activeThread}`)
  //     .then((response) => response.json())
  //     .then((data) => setMessages(data));
  // }, [activeThread]);

  const sendMessage = async () => {
    if (!userInput.trim()) return;

    const newMessage = { sender: "user", message: userInput };
    setMessages((prevMessages) => [...prevMessages, newMessage]);
    setUserInput("");

    try {
      setIsStreaming(true);
      const response = await fetch(FLASK_API_URL, {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ thread_id: activeThread, prompt: userInput }),
      });

      if (!response.ok) {
        console.error("Failed to stream response");
        setIsStreaming(false);
        return;
      }

      const reader = response.body.getReader();
      const decoder = new TextDecoder("utf-8");
      let streamingMessage = "";

      while (true) {
        const { done, value } = await reader.read();
        if (done) break;

        const chunk = decoder.decode(value, { stream: true });
        streamingMessage += chunk;

        setMessages((prevMessages) => {
          const updatedMessages = [...prevMessages];
          const lastMessage = updatedMessages[updatedMessages.length - 1];

          if (lastMessage && lastMessage.sender === "bot") {
            lastMessage.message = streamingMessage;
          } else {
            updatedMessages.push({ sender: "bot", message: streamingMessage });
          }

          return updatedMessages;
        });
      }

      setIsStreaming(false);
    } catch (error) {
      console.error("Error during streaming:", error);
      setIsStreaming(false);
    }
  };

  const renderMessage = (message) => {
    if (message.message.includes("```")) {
      // Handle code block
      const parts = message.message.split(/```/g);
      return parts.map((part, index) => (
        <div key={index}>
          {index % 2 === 0 ? (
            <p style={{ whiteSpace: "pre-wrap", margin: "5px 0" }}>{part}</p>
          ) : (
            <pre
              style={{
                backgroundColor: "#333",
                color: "#f5f5f5",
                padding: "10px",
                borderRadius: "5px",
                margin: "5px 0",
                overflowX: "auto",
              }}
            >
              <code>{part}</code>
            </pre>
          )}
        </div>
      ));
    }

    // Plain text message
    return <p style={{ whiteSpace: "pre-wrap", margin: "5px 0" }}>{message.message}</p>;
  };

  const handleKeyDown = (event) => {
    if (event.key === "Enter") {
      sendMessage();
    }
  };

  return (
    <div
      style={{
        width: "80%",
        display: "flex",
        flexDirection: "column",
        padding: "10px",
        backgroundColor: "#1e1e1e",
        color: "#f5f5f5",
      }}
    >
      <div
        style={{
          flex: 1,
          overflowY: "auto",
          border: "1px solid #333",
          borderRadius: "5px",
          marginBottom: "10px",
          padding: "10px",
          backgroundColor: "#121212",
        }}
      >
        {messages.map((msg, index) => (
          <div
            key={index}
            style={{
              display: "flex",
              justifyContent: msg.sender === "user" ? "flex-end" : "flex-start",
              marginBottom: "10px",
            }}
          >
            <div
              style={{
                maxWidth: "70%",
                padding: "10px",
                backgroundColor: msg.sender === "user" ? "#333" : "#444",
                color: msg.sender === "user" ? "#ffa726" : "#f5f5f5",
                borderRadius: "10px",
                textAlign: "left",
              }}
            >
              {renderMessage(msg)}
            </div>
          </div>
        ))}
        {isStreaming && (
          <div style={{ color: "#64b5f6" }}>
            <em>Bot is typing...</em>
          </div>
        )}
      </div>
      <div style={{ display: "flex" }}>
        <input
          type="text"
          value={userInput}
          onChange={(e) => setUserInput(e.target.value)}
          onKeyDown={handleKeyDown}
          placeholder="Type your message..."
          style={{
            flex: 1,
            padding: "10px",
            border: "1px solid #333",
            borderRadius: "5px",
            backgroundColor: "#333",
            color: "#f5f5f5",
          }}
        />
        <button
          onClick={sendMessage}
          style={{
            marginLeft: "10px",
            padding: "10px",
            backgroundColor: "#333",
            color: "#f5f5f5",
            border: "none",
            borderRadius: "5px",
            cursor: "pointer",
          }}
        >
          Send
        </button>
      </div>
    </div>
  );
};

export default ChatBox;