import React, { useState, useEffect, useRef } from "react";
import { useIntl } from "react-intl";
import { Helmet } from "react-helmet";
import axios from "axios";
import { auth } from "@strapi/helper-plugin";
import {
  Button,
  TextInput,
  SingleSelect,
  SingleSelectOption,
  Layout,
  HeaderLayout,
  ContentLayout,
  Main,
  Box,
  Card,
  CardBody,
  CardContent,
  Grid,
  GridItem,
  ActionLayout,
  Tab,
  Stack,
  Tabs,
  TabGroup,
  TabPanels,
  TabPanel,
  Typography
} from "@strapi/design-system";
import { PaperPlane, Command, Cog, Picture, PlusCircle } from "@strapi/icons";

import CustomTab from "./tab";
import Response from "./response";
import Help from "../Help";
import LoadingOverlay from "../Loading";
import Integration from "../Integration";

const Home = () => {
  const { formatMessage } = useIntl();
  const imageFormats = [
    formatMessage({ id: "strapi-supergpt.homePage.imageFormat" }),
    "1024x1024",
    "1024x1792",
    "1792x1024",
  ];
  const [prompt, setPrompt] = useState("");
  const [highlightedId, setHighlighted] = useState(0);
  const [convos, setConvos] = useState([]);
  const [error, setError] = useState("");
  const [format, setFormat] = useState(imageFormats[0]);
  const [loading, setLoading] = useState(false);
  const messagesEndRef = useRef(null);
  const [isModalVisible, setIsModalVisible] = useState(false);
  const [isApiIntegrationModalVisible, setIsApiIntegrationModalVisible] =
    useState(false);

  const instance = axios.create({
    baseURL: process.env.STRAPI_ADMIN_BACKEND_URL,
    headers: {
      Authorization: `Bearer ${auth.get("jwtToken")}`,
      "Content-Type": "application/json",
    },
  });

  const handlePromptChange = (e) => {
    setError("");
    setPrompt(e.target.value);
  };

  const handleImageSizeChange = (e) => {
    setFormat(e);
  };

  const setSelectedResponse = (index) => {
    if (index >= convos.length) {
      setError(formatMessage({id: "strapi-supergpt.homePage.error.unselectableTab"}));
      return;
    }
    const selectedConvo = convos[index];
    if (!selectedConvo.content.length) {
      instance.get(`/strapi-supergpt/convo/${selectedConvo.id}`)
        .then(content => {
          const updatedConvos = [...convos];
          updatedConvos[index] = { ...selectedConvo, content: content.data };
          setConvos(updatedConvos);
        });
    }
    setHighlighted(index);
  };

  const handleCreateTab = async () => {
    const defaultConvoName = formatMessage({id: "strapi-supergpt.homePage.convo.new.name"})
    const { data: newConvo } = await instance.post(`/strapi-supergpt/convo`, {
      name: `${defaultConvoName} ${convos.length + 1}`
    });
    setConvos(prevConvos => [...prevConvos, newConvo]);
    setHighlighted(newConvo.id);
  };

  const handleSaveTab = async (e) => {
    const id = convos[highlightedId]
    await instance.put(`/strapi-supergpt/convo`, {
      name: id,
      content: convos[highlightedId],
    })
    .then(convo => setConvos([...convos, convo.data]));
  };

  const handleDeleteTab = async (id) => {
    if (convos.length > 1) {
      await instance.delete(`/strapi-supergpt/convo/${id}`);
      setConvos(prevConvos => {
        const updatedConvos = prevConvos.filter(convo => convo.id !== id);
        const newHighlightedId = updatedConvos.length > 0 ? updatedConvos[0].id : null;
        setHighlighted(newHighlightedId);
        return updatedConvos;
      });
    } else {
      await instance.put(`/strapi-supergpt/convo/${id}`, {
        name: formatMessage({ id: "strapi-supergpt.homePage.convo.default.name" }),
        content: [],
      });
      setConvos([{
        id,
        name: formatMessage({ id: "strapi-supergpt.homePage.convo.default.name" }),
        content: [],
      }]);
      setHighlighted(id);
    }
  };

  const handleSubmit = async (e) => {
    e.preventDefault();
    setError("");
    if (!prompt) {
      setError(formatMessage({id: "strapi-supergpt.homePage.error.promptRequired"}));
      return;
    }

    let response;

    try {
      if (e.target.name === "picture") {
        if (format === imageFormats[0]) {
          setError(formatMessage({id: "strapi-supergpt.homePage.error.imageSizeRequired"}));
          return;
        }
        setLoading(true);
        const data = await instance.post("/strapi-supergpt/generateImage", {
          prompt: prompt,
          size: format,
        })
        setLoading(false);
        response = data.data;
      } else {
        setLoading(true);
        const format = formatMessage({ id: "strapi-supergpt.homePage.prompt.format"})
        const data = await instance.post("/strapi-supergpt/prompt", {
          prompt: `${prompt} ${format}?`,
        })
        setLoading(false);
        response = data.data;
      }
    } catch (e) {
      const errorMessage =  e.message || e.response?.data?.error || "An unknown error occurred";
      setError(errorMessage);
      setLoading(false);
    }

    let highlightedConvo = convos[highlightedId];

    highlightedConvo.content = [
      ...highlightedConvo.content,
      {
        name: "you",
        message: prompt
      },
      {
        name: "chatgpt",
        message: response.response,
      }
    ];

    await instance.put(`/strapi-supergpt/convo/${highlightedConvo.id}`, {
      name: highlightedConvo.name,
      content: highlightedConvo.content
    });

    setPrompt("");
  };

  useEffect(() => {
    if (convos.length === 0) {
      instance.get('/strapi-supergpt/convos')
        .then(conversations => {
          if (conversations.data.length > 0) {
            setConvos(conversations.data)
          } else {
            handleCreateTab();
          }
        });
    }
  }, [setConvos]);

  useEffect(() => {
    if (messagesEndRef.current) {
      messagesEndRef.current.scrollIntoView({ behavior: "smooth" });
    }
  }, []);

  return (
    <Layout>
      <Helmet title={"strapi-supergpt"} />
      <Main aria-busy={false}>
        <HeaderLayout
          title={
            <Box display="flex" alignItems="center">
              <Typography variant="alpha" as="h1">
                SuperGPT
              </Typography>
            </Box>
          }
          subtitle={formatMessage({
            id: "strapi-supergpt.homePage.header",
          })}
        />

        <ActionLayout
          startActions={
            <SingleSelect onChange={handleImageSizeChange} value={format}>
              {imageFormats.map((format, idx) => (
                <SingleSelectOption key={idx} value={format}>
                  {format}
                </SingleSelectOption>
              ))}
            </SingleSelect>
          }
          endActions={
            <Stack horizontal gap={2}>
              <Button
                variant="secondary"
                startIcon={<Cog />}
                onClick={() => setIsApiIntegrationModalVisible(true)}
              >
                {formatMessage({ id: "strapi-supergpt.homePage.API_Integration.button" })}
              </Button>
              <Button
                variant="secondary"
                startIcon={<Command />}
                onClick={() => setIsModalVisible(true)}
              >
                {formatMessage({ id: "strapi-supergpt.homePage.help.button" })}
              </Button>
            </Stack>
          }
        />

        <ContentLayout>
          <TabGroup onTabChange={setSelectedResponse}>
            <Tabs>
              {convos.length > 0 && convos.map(convo => (
                <CustomTab
                  key={convo.id}
                  value={convo.id}
                  onRename={handleSaveTab}
                  onDelete={() => handleDeleteTab(convo.id)}
                >
                  {convo.name}
                </CustomTab>
              ))}
              <Tab onClick={handleCreateTab}><PlusCircle /></Tab>
            </Tabs>
            <TabPanels>
              {convos.length > 0 && convos.map((convo) => (
                <TabPanel key={convo.id}>
                  <Card>
                    <CardBody
                      style={{
                        height: "64vh",
                        overflowY: "scroll",
                        width: "100%"
                      }}
                    >
                      <CardContent>
                        <LoadingOverlay isLoading={loading} />
                          {convo.content.map((response, index) => (
                            <Response key={`${index}`}>
                              {response}
                            </Response>
                          ))}
                          <div ref={messagesEndRef} />
                      </CardContent>
                    </CardBody>
                  </Card>
                </TabPanel>
              ))}
            </TabPanels>
          </TabGroup>
          <Box>
            <form>
              <Grid spacing={1} gap={2} paddingTop={4}>
                <GridItem col={11}>
                  <TextInput
                    id="chatInput"
                    placeholder={formatMessage({ id: "strapi-supergpt.homePage.prompt.placeholder" })}
                    aria-label="Content"
                    name="prompt"
                    error={error}
                    onChange={handlePromptChange}
                    value={prompt}
                    disabled={loading}
                    onPaste={handlePromptChange}
                  />
                </GridItem>
                <GridItem style={{ display: 'flex', justifyContent: 'space-between', gap: '0.5rem' }}>
                  <Button
                    size="L"
                    name="prompt"
                    startIcon={<PaperPlane />}
                    value="prompt"
                    loading={loading}
                    onClick={handleSubmit}
                  >
                    {formatMessage({ id: "strapi-supergpt.homePage.prompt.button" })}
                  </Button>
                  <Button
                    size="L"
                    name="picture"
                    value="picture"
                    onClick={handleSubmit}
                    startIcon={<Picture />}
                  >
                    {formatMessage({ id: "strapi-supergpt.homePage.image.button" })}
                  </Button>
                </GridItem>
              </Grid>
            </form>
          </Box>
        </ContentLayout>
        <Help
          isOpen={isModalVisible}
          onClose={() => setIsModalVisible(false)}
        />
        <Integration
          isOpen={isApiIntegrationModalVisible}
          onClose={() => setIsApiIntegrationModalVisible(false)}
        />
      </Main>
    </Layout>
  );
};

export default Home;