import React from "react";
import { Accordion, AccordionDetails, AccordionSummary, Alert, Box, Button, Chip, LinearProgress, Typography } from "@mui/material";
import ExpandMoreIcon from "@mui/icons-material/ExpandMore";
import { useI18n } from "../../i18n/I18nProvider";
import { localizeCompletenessLabel } from "./careerCompletenessLabels";
import { PageSection } from "../../layout/PageLayout";

// Display-only slice of the Career Profile page: the completeness meter, the "missing" chips, and the
// version-history accordion. Extracted from CareerProfilePage as the first step of the Phase 1
// component split. It owns no state and makes no API calls — the parent still holds `completeness`
// and `versions` and performs the restore — so save/load behaviour is unchanged.
export type CareerCompletenessView = {
  percent: number;
  missing: string[];
};

export type CareerVersionView = {
  version: number;
  source: string;
  createdAtUtc: string;
  isCurrent: boolean;
};

export default function ProfileCompleteness({
  completeness,
  versions,
  loading,
  onRestore,
  showSummary = true,
  versionsLoading = false,
  versionsError = null,
  onRetryVersions,
  restoreDisabled = false,
  restoreError = null,
}: {
  completeness: CareerCompletenessView | null;
  versions: CareerVersionView[];
  loading: boolean;
  onRestore: (version: number) => void;
  showSummary?: boolean;
  versionsLoading?: boolean;
  versionsError?: string | null;
  onRetryVersions?: () => void;
  restoreDisabled?: boolean;
  restoreError?: string | null;
}) {
  const { language, t } = useI18n();
  const restoreHelpId = React.useId();
  const historyRef = React.useRef<HTMLDivElement>(null);

  const locale = language === "nb" ? "nb-NO" : "en";
  const rows = versions.slice(0, 12).map((v) => (
    <Box key={v.version} sx={{ display: "flex", alignItems: "center", justifyContent: "space-between", gap: 1, flexWrap: "wrap", minWidth: 0 }}>
      <Typography variant="body2" sx={{ color: "text.secondary", overflowWrap: "anywhere" }}>
        v{v.version} · {v.source} · {new Date(v.createdAtUtc).toLocaleString(locale)}{v.isCurrent ? ` · ${t("profileCvVersionCurrent")}` : ""}
      </Typography>
      {!v.isCurrent ? (
        <Button size="small" variant="text" disabled={loading || versionsLoading || restoreDisabled} aria-describedby={restoreDisabled ? restoreHelpId : undefined} onClick={() => { historyRef.current?.focus(); onRestore(v.version); }}>{t("careerRestoreVersion", { version: v.version })}</Button>
      ) : null}
    </Box>
  ));

  return (
    <Box ref={historyRef} role="group" aria-label={t("profileCvVersionHistory", { count: versions.length })} tabIndex={-1} sx={{ mb: 2 }}>
      {showSummary && completeness ? (
        <>
          <Box sx={{ display: "flex", justifyContent: "space-between", alignItems: "baseline", gap: 2, flexWrap: "wrap", mb: 1 }}>
            <Typography variant="subtitle1" sx={{ fontWeight: 900 }}>{t("profileCvCompletenessTitle")}</Typography>
            <Typography variant="h6" sx={{ fontWeight: 900 }}>{completeness.percent}%</Typography>
          </Box>
          <LinearProgress
            aria-label={t("profileCvCompletenessTitle")}
            variant="determinate"
            value={completeness.percent}
            color={completeness.percent >= 80 ? "success" : completeness.percent >= 40 ? "primary" : "warning"}
            sx={{ height: 8, borderRadius: 999 }}
          />
          {completeness.missing.length > 0 ? (
            <Box sx={{ display: "flex", gap: 0.75, flexWrap: "wrap", alignItems: "center", mt: 1.25 }}>
              <Typography variant="body2" sx={{ color: "text.secondary" }}>{t("profileCvCompletenessMissing")}</Typography>
              {completeness.missing.map((label) => (
                <Chip key={label} size="small" label={localizeCompletenessLabel(label, t)} sx={{ height: 22, fontWeight: 700 }} />
              ))}
            </Box>
          ) : (
            <Typography variant="body2" sx={{ color: "success.main", mt: 1.25, fontWeight: 700 }}>{t("profileCvCompletenessComplete")}</Typography>
          )}
        </>
      ) : null}
      <PageSection title={t("profileCvVersionHistory", { count: versions.length })} surface>
        {versionsLoading ? <LinearProgress aria-label={t("careerHistoryLoading")} /> : null}
        {versionsError !== null ? <Alert severity="error" action={onRetryVersions ? <Button color="inherit" disabled={versionsLoading} onClick={() => { historyRef.current?.focus(); onRetryVersions(); }}>{t("retry")}</Button> : undefined}>
          <Typography component="p" variant="body2" sx={{ fontWeight: 600 }}>{t("careerHistoryLoadFailed")}</Typography>
          {versionsError ? <Typography component="p" variant="body2" sx={{ overflowWrap: "anywhere" }}>{versionsError}</Typography> : null}
        </Alert> : null}
        {restoreError !== null ? <Alert severity="error">
          <Typography component="p" variant="body2" sx={{ fontWeight: 600 }}>{t("careerRestoreFailed")}</Typography>
          {restoreError ? <Typography component="p" variant="body2" sx={{ overflowWrap: "anywhere" }}>{restoreError}</Typography> : null}
        </Alert> : null}
        {restoreDisabled ? <Typography id={restoreHelpId} variant="body2" color="text.secondary">{t("careerSaveBeforeRestore")}</Typography> : null}
        {versions.length > 1 ? (
        <Accordion disableGutters elevation={0} sx={{ mt: showSummary ? 1.5 : 0, "&:before": { display: "none" }, backgroundColor: "transparent" }}>
          <AccordionSummary expandIcon={<ExpandMoreIcon />} sx={{ px: 0, minHeight: 0 }}>
            <Typography variant="body2" sx={{ fontWeight: 700 }}>{t("profileCvVersionHistory", { count: versions.length })}</Typography>
          </AccordionSummary>
          <AccordionDetails sx={{ px: 0, pt: 0 }}>
            <Box sx={{ display: "grid", gap: 0.75 }}>
              {rows}
            </Box>
          </AccordionDetails>
        </Accordion>
        ) : rows}
        {versions.length === 0 && !versionsLoading && versionsError === null ? <Typography variant="body2" color="text.secondary">{t("careerHistoryEmpty")}</Typography> : null}
      </PageSection>
    </Box>
  );
}