import React, { useEffect, useState } from "react";
import { useNavigate } from "react-router-dom";

import { Box, Button, IconButton, LinearProgress, Paper, Stack, Typography } from "@mui/material";
import CheckCircleIcon from "@mui/icons-material/CheckCircle";
import CloseIcon from "@mui/icons-material/Close";
import RadioButtonUncheckedIcon from "@mui/icons-material/RadioButtonUnchecked";
import { alpha, useTheme } from "@mui/material/styles";

import { api } from "../api";
import { useI18n } from "../i18n/I18nProvider";
import { getUserKeyFromToken } from "../themePrefs";

type MeResponse = {
  email?: string | null;
  firstName?: string | null;
  lastName?: string | null;
  displayName?: string | null;
};
type CareerProfileResponse = {
  cvText?: string | null;
  profile?: {
    summary?: string[];
    jobs?: unknown[];
    education?: unknown[];
    projects?: unknown[];
    certifications?: unknown[];
    languages?: unknown[];
    otherSections?: unknown[];
    skills?: string[];
    interests?: string[];
  };
};
type ConnectionStatus = { connected?: boolean };

export default function OnboardingChecklist({ hasJobs }: { hasJobs: boolean }) {
  const theme = useTheme();
  const navigate = useNavigate();
  const { t } = useI18n();
  const dismissalKey = `onboardingDismissed:${getUserKeyFromToken()}`;
  const [dismissed, setDismissed] = useState(() => window.localStorage.getItem(dismissalKey) === "true");
  const [status, setStatus] = useState<{ profile: boolean; cv: boolean; email: boolean } | null>(null);

  useEffect(() => {
    let active = true;
    Promise.all([
      api.get<MeResponse>("/auth/me"),
      api.get<CareerProfileResponse>("/career/profile"),
      Promise.all(["/gmail/status", "/microsoft-graph/status", "/imap/status"].map((url) =>
        api.get<ConnectionStatus>(url).then((r) => Boolean(r.data?.connected)).catch(() => false),
      )),
    ]).then(([me, career, connections]) => {
      if (!active) return;
      const profile = career.data?.profile;
      const structuredCount = [
        ...(profile?.summary ?? []),
        ...(profile?.jobs ?? []),
        ...(profile?.education ?? []),
        ...(profile?.projects ?? []),
        ...(profile?.certifications ?? []),
        ...(profile?.languages ?? []),
        ...(profile?.otherSections ?? []),
        ...(profile?.skills ?? []),
        ...(profile?.interests ?? []),
      ].length;
      setStatus({
        profile: Boolean(me.data?.displayName?.trim() || me.data?.firstName?.trim() || me.data?.lastName?.trim()),
        cv: structuredCount > 0 || Boolean(career.data?.cvText?.trim()),
        email: connections.some(Boolean),
      });
    }).catch(() => { if (active) setStatus({ profile: false, cv: false, email: false }); });
    return () => { active = false; };
  }, []);

  if (!status || dismissed) return null;

  const steps = [
    { done: true, label: t("onboardingStepSignup"), actionLabel: "" },
    { done: true, label: t("onboardingStepVerify"), actionLabel: "" },
    { done: status.profile, label: t("onboardingStepProfile"), action: () => navigate("/profile"), actionLabel: t("onboardingStepProfileAction") },
    { done: status.cv, label: t("onboardingStepCv"), action: () => navigate("/career"), actionLabel: t("onboardingStepCvAction") },
    { done: status.email, label: t("onboardingStepEmail"), action: () => navigate("/settings/connected-accounts"), actionLabel: t("onboardingStepEmailAction") },
    { done: hasJobs, label: t("onboardingStepJob"), action: () => navigate("/jobs"), actionLabel: t("onboardingStepJobAction") },
  ];
  const completed = steps.filter((step) => step.done).length;
  if (completed === steps.length) return null;

  return (
    <Paper sx={{ p: 2.25, mb: 2, borderRadius: 4, border: "1px solid", borderColor: alpha(theme.palette.primary.main, 0.25), background: alpha(theme.palette.primary.main, 0.04) }}>
      <Box sx={{ display: "flex", alignItems: "flex-start", justifyContent: "space-between", gap: 1 }}>
        <Typography sx={{ fontWeight: 900, mb: 0.25 }}>{t("onboardingTitle")}</Typography>
        <IconButton
          size="small"
          aria-label={t("onboardingDismiss")}
          onClick={() => {
            window.localStorage.setItem(dismissalKey, "true");
            setDismissed(true);
          }}
        >
          <CloseIcon fontSize="small" />
        </IconButton>
      </Box>
      <Typography variant="body2" sx={{ color: "text.secondary" }}>{t("onboardingBody")}</Typography>
      <Typography variant="caption" sx={{ color: "text.secondary" }}>{completed} / {steps.length}</Typography>
      <LinearProgress
        variant="determinate"
        value={(completed / steps.length) * 100}
        aria-label={t("checklistProgress", { completed, total: steps.length })}
        sx={{ my: 1.5, borderRadius: 2 }}
      />
      <Stack spacing={1}>
        {steps.map((step) => (
          <Box key={step.label} sx={{ display: "flex", alignItems: "center", justifyContent: "space-between", gap: 1.5, flexWrap: "wrap" }}>
            <Box sx={{ display: "flex", alignItems: "center", gap: 1 }}>
              {step.done ? <CheckCircleIcon fontSize="small" color="success" /> : <RadioButtonUncheckedIcon fontSize="small" sx={{ color: "text.secondary" }} />}
              <Typography variant="body2" sx={{ fontWeight: step.done ? 400 : 700, color: step.done ? "text.secondary" : "text.primary", textDecoration: step.done ? "line-through" : "none" }}>
                {step.label}
              </Typography>
            </Box>
            {!step.done && step.action ? <Button size="small" variant="text" onClick={step.action}>{step.actionLabel}</Button> : null}
          </Box>
        ))}
      </Stack>
    </Paper>
  );
}