import React, { useState, useCallback, useRef } from 'react';
import {
  Tabs,
  Tab,
  Box,
} from '@mui/material';
import { SxProps } from '@mui/material';

import { ChatQuery, Query } from './ChatQuery';
import { MessageList, BackstoryMessage } from './Message';
import { Conversation } from './Conversation';
import { BackstoryPageProps } from './BackstoryTab';

import './ResumeBuilderPage.css';

/**
 * ResumeBuilder component
 * 
 * A responsive component that displays job descriptions, generated resumes and fact checks
 * with different layouts for mobile and desktop views.
 */
const ResumeBuilderPage: React.FC<BackstoryPageProps> = (props: BackstoryPageProps) => {
  const {
    sx,
    sessionId,
    setSnack,
    submitQuery,
  } = props
  // State for editing job description
  const [hasJobDescription, setHasJobDescription] = useState<boolean>(false);
  const [hasResume, setHasResume] = useState<boolean>(false);
  const [hasFacts, setHasFacts] = useState<boolean>(false);
  const jobConversationRef = useRef<any>(null);
  const resumeConversationRef = useRef<any>(null);
  const factsConversationRef = useRef<any>(null);

  const [activeTab, setActiveTab] = useState<number>(0);

  /**
   * Handle tab change for mobile view
   */
  const handleTabChange = (_event: React.SyntheticEvent, newValue: number): void => {
    setActiveTab(newValue);
  };

  const handleJobQuery = (query: Query) => {
    console.log(`handleJobQuery: ${query.prompt} -- `, jobConversationRef.current ? ' sending' : 'no handler');
    jobConversationRef.current?.submitQuery(query);
  };

  const handleResumeQuery = (query: Query) => {
    console.log(`handleResumeQuery: ${query.prompt} -- `, resumeConversationRef.current ? ' sending' : 'no handler');
    resumeConversationRef.current?.submitQuery(query);
  };

  const handleFactsQuery = (query: Query) => {
    console.log(`handleFactsQuery: ${query.prompt} -- `, factsConversationRef.current ? ' sending' : 'no handler');
    factsConversationRef.current?.submitQuery(query);
  };

  const filterJobDescriptionMessages = useCallback((messages: MessageList): MessageList => {
    if (messages === undefined || messages.length === 0) {
      return [];
    }

    if (messages.length > 0) {
      messages[0].role = 'content';
      messages[0].title = 'Job Description';
      messages[0].disableCopy = false;
      messages[0].expandable = true;
    }

    if (-1 !== messages.findIndex(m => m.status === 'done')) {
      setHasResume(true);
      setHasFacts(true);
    }

    return messages;

    if (messages.length > 1) {
      setHasResume(true);
      setHasFacts(true);
    }


    if (messages.length > 3) {
      // messages[2] is Show job requirements
      messages[3].role = 'job-requirements';
      messages[3].title = 'Job Requirements';
      messages[3].disableCopy = false;
      messages[3].expanded = false;
      messages[3].expandable = true;
    }

    /* Filter out the 2nd and 3rd (0-based) */
    const filtered = messages;//.filter((m, i) => i !== 1 && i !== 2);
    console.warn("Set filtering back on");

    return filtered;
  }, [setHasResume, setHasFacts]);

  const filterResumeMessages = useCallback((messages: MessageList): MessageList => {
    if (messages === undefined || messages.length === 0) {
      return [];
    }

    return messages;

    if (messages.length > 1) {
      // messages[0] is Show Qualifications
      messages[1].role = 'qualifications';
      messages[1].title = 'Candidate qualifications';
      messages[1].disableCopy = false;
      messages[1].expanded = false;
      messages[1].expandable = true;
    }

    if (messages.length > 3) {
      // messages[2] is Show Resume
      messages[3].role = 'resume';
      messages[3].title = 'Generated Resume';
      messages[3].disableCopy = false;
      messages[3].expanded = true;
      messages[3].expandable = true;
    }

    /* Filter out the 1st and 3rd messages (0-based) */
    const filtered = messages.filter((m, i) => i !== 0 && i !== 2);

    return filtered;
  }, []);

  const filterFactsMessages = useCallback((messages: MessageList): MessageList => {
    if (messages === undefined || messages.length === 0) {
      return [];
    }

    if (messages.length > 1) {
      // messages[0] is Show verification
      messages[1].role = 'fact-check';
      messages[1].title = 'Fact Check';
      messages[1].disableCopy = false;
      messages[1].expanded = true;
      messages[1].expandable = true;
    }

    /* Filter out the 1st (0-based) */
    const filtered = messages.filter((m, i) => i !== 0);

    return filtered;
  }, []);

  const jobResponse = useCallback(async (message: BackstoryMessage) => {
    console.log('onJobResponse', message);
    if (message.actions && message.actions.includes("job_description")) {
      await jobConversationRef.current.fetchHistory();
    }
    if (message.actions && message.actions.includes("resume_generated")) {
      await resumeConversationRef.current.fetchHistory();
      setHasResume(true);
      setActiveTab(1); // Switch to Resume tab
    }
    if (message.actions && message.actions.includes("facts_checked")) {
      await factsConversationRef.current.fetchHistory();
      setHasFacts(true);
    }
  }, [setHasFacts, setHasResume, setActiveTab]);

  const resumeResponse = useCallback((message: BackstoryMessage): void => {
    console.log('onResumeResponse', message);
    setHasFacts(true);
  }, [setHasFacts]);

  const factsResponse = useCallback((message: BackstoryMessage): void => {
    console.log('onFactsResponse', message);
  }, []);

  const resetJobDescription = useCallback(() => {
    setHasJobDescription(false);
    setHasResume(false);
    setHasFacts(false);
  }, [setHasJobDescription, setHasResume, setHasFacts]);

  const resetResume = useCallback(() => {
    setHasResume(false);
    setHasFacts(false);
  }, [setHasResume, setHasFacts]);

  const resetFacts = useCallback(() => {
    setHasFacts(false);
  }, [setHasFacts]);

  const renderJobDescriptionView = useCallback((sx: SxProps) => {
    console.log('renderJobDescriptionView');
    const jobDescriptionQuestions = [
      <Box sx={{ display: "flex", flexDirection: "column" }}>
        <ChatQuery query={{ prompt: "What are the key skills necessary for this position?", tunables: { enable_tools: false } }} submitQuery={handleJobQuery} />
        <ChatQuery query={{ prompt: "How much should this position pay (accounting for inflation)?", tunables: { enable_tools: false } }} submitQuery={handleJobQuery} />
      </Box>,
    ];

    const jobDescriptionPreamble: MessageList = [{
      role: 'info',
      content: `Once you paste a job description and press **Generate Resume**, Backstory will perform the following actions:

1. **Job Analysis**: LLM extracts requirements from '\`Job Description\`' to generate a list of desired '\`Skills\`'.
2. **Candidate Analysis**: LLM determines candidate qualifications by performing skill assessments.
    
    For each '\`Skill\`' from **Job Analysis** phase:

    1. **RAG**: Retrieval Augmented Generation collection is queried for context related content for each '\`Skill\`'.
    2. **Evidence Creation**: LLM is queried to generate supporting evidence of '\`Skill\`' from the '\`RAG\`' and '\`Candidate Resume\`'.
3. **Resume Generation**: LLM is provided the output from the **Candidate Analysis:Evidence Creation** phase and asked to generate a professional resume.

See [About > Resume Generation Architecture](/about/resume-generation) for more details.
`,
      disableCopy: true
    }];


    if (!hasJobDescription) {
      return <Conversation
        ref={jobConversationRef}
        {...{
          type: "job_description",
          actionLabel: "Generate Resume",
          preamble: jobDescriptionPreamble,
          hidePreamble: true,
          placeholder: "Paste a job description, then click Generate...",
          multiline: true,
          resetLabel: `job description${hasFacts ? ", resume, and fact check" : hasResume ? " and resume" : ""}`,
          messageFilter: filterJobDescriptionMessages,
          resetAction: resetJobDescription,
          onResponse: jobResponse,
          sessionId,
          setSnack,
          submitQuery,
          sx,
        }}
      />

    } else {
      return <Conversation
        ref={jobConversationRef}
        {...{
          type: "job_description",
          actionLabel: "Send",
          placeholder: "Ask a question about this job description...",
          resetLabel: `job description${hasFacts ? ", resume, and fact check" : hasResume ? " and resume" : ""}`,
          messageFilter: filterJobDescriptionMessages,
          defaultPrompts: jobDescriptionQuestions,
          resetAction: resetJobDescription,
          onResponse: jobResponse,
          sessionId,
          setSnack,
          submitQuery,
          sx,
        }}
      />
    }
  }, [filterJobDescriptionMessages, hasJobDescription, sessionId, setSnack, jobResponse, resetJobDescription, hasFacts, hasResume, submitQuery]);

  /**
   * Renders the resume view with loading indicator
   */
  const renderResumeView = useCallback((sx: SxProps) => {
    const resumeQuestions = [
      <Box sx={{ display: "flex", flexDirection: "column" }}>
        <ChatQuery query={{ prompt: "Is this resume a good fit for the provided job description?", tunables: { enable_tools: false } }} submitQuery={handleResumeQuery} />
        <ChatQuery query={{ prompt: "Provide a more concise resume.", tunables: { enable_tools: false } }} submitQuery={handleResumeQuery} />
      </Box>,
    ];

    if (!hasFacts) {
      return <Conversation
        ref={resumeConversationRef}
        {...{
          type: "resume",
          actionLabel: "Fact Check",
          defaultQuery: "Fact check the resume.",
          resetLabel: `job description${hasFacts ? ", resume, and fact check" : hasResume ? " and resume" : ""}`,
          messageFilter: filterResumeMessages,
          onResponse: resumeResponse,
          resetAction: resetResume,
          sessionId,
          setSnack,
          submitQuery,
          sx,
        }}
      />
    } else {
      return <Conversation
        ref={resumeConversationRef}
        {...{
          type: "resume",
          actionLabel: "Send",
          placeholder: "Ask a question about this job resume...",
          resetLabel: `job description${hasFacts ? ", resume, and fact check" : hasResume ? " and resume" : ""}`,
          messageFilter: filterResumeMessages,
          onResponse: resumeResponse,
          resetAction: resetResume,
          sessionId,
          setSnack,
          defaultPrompts: resumeQuestions,
          submitQuery,
          sx,
        }}
      />
    }
  }, [filterResumeMessages, hasFacts, sessionId, setSnack, resumeResponse, resetResume, hasResume, submitQuery]);

  /**
   * Renders the fact check view
   */
  const renderFactCheckView = useCallback((sx: SxProps) => {
    const factsQuestions = [
      <Box sx={{ display: "flex", flexDirection: "column" }}>
        <ChatQuery query={{ prompt: "Rewrite the resume to address any discrepancies.", tunables: { enable_tools: false } }} submitQuery={handleFactsQuery} />
      </Box>,
    ];

    return <Conversation
      ref={factsConversationRef}
      {...{
        type: "fact_check",
        actionLabel: "Send",
        placeholder: "Ask a question about any discrepencies...",
        resetLabel: `job description${hasFacts ? ", resume, and fact check" : hasResume ? " and resume" : ""}`,
        messageFilter: filterFactsMessages,
        defaultPrompts: factsQuestions,
        resetAction: resetFacts,
        onResponse: factsResponse,
        sessionId,
        submitQuery,
        setSnack,
        sx,
      }}
    />
  }, [ sessionId, setSnack, factsResponse, filterFactsMessages, resetFacts, hasResume, hasFacts, submitQuery]);

  return (
    <Box className="ResumeBuilder"
      sx={{
      p: 0,
      m: 0,
      display: "flex",
      flexGrow: 1,
      margin: "0 auto",
      overflow: "hidden",
      backgroundColor: "#F5F5F5",
      flexDirection: "column",
      maxWidth: "1024px",
    }}
    >
      {/* Tabs */}
      <Tabs
        value={activeTab}
        onChange={handleTabChange}
        variant="fullWidth"
        sx={{ bgcolor: 'background.paper' }}
      >
        <Tab value={0} label="Job Description" />
        {hasResume && <Tab value={1} label="Resume" />}
        {hasFacts && <Tab value={2} label="Fact Check" />}
      </Tabs>

      {/* Document display area */}
      <Box sx={{
        display: 'flex', flexDirection: 'column', flexGrow: 1, p: 0, width: "100%", ...sx,
        overflow: "hidden"
      }}>
        <Box sx={{ display: activeTab === 0 ? "flex" : "none" }}>{renderJobDescriptionView({ height: "calc(100vh - 72px - 48px)" })}</Box>
        <Box sx={{ display: activeTab === 1 ? "flex" : "none" }}>{renderResumeView({ height: "calc(100vh - 72px - 48px)" })}</Box>
        <Box sx={{ display: activeTab === 2 ? "flex" : "none" }}>{renderFactCheckView({ height: "calc(100vh - 72px - 48px)" })}</Box>
      </Box>
    </Box>
  );
};

export {
  ResumeBuilderPage
};