import React, { useId, useMemo, useState } from "react";
import CheckCircleIcon from "@mui/icons-material/CheckCircle";
import { Box, Button, Chip, Paper, Stack, Typography } from "@mui/material";

import { CvTheme, getVisibleCvThemes } from "../cvBuilder";
import { useI18n } from "../i18n/I18nProvider";
import type { TranslationKey } from "../i18n/translations";
import CvTemplateThumbnail from "./CvTemplateThumbnail";

type Props = {
  themes: CvTheme[];
  selectedId: string;
  onSelect: (theme: CvTheme) => void;
  previewHeight?: number;
  showDescriptions?: boolean;
  disabled?: boolean;
};

const templateLabels = new Map<string, [TranslationKey, TranslationKey, TranslationKey]>([
  ["modern", ["cvTemplateModernName", "cvTemplateCategoryModern", "cvTemplateModernDescription"]],
  ["minimal", ["cvTemplateMinimalName", "cvTemplateCategoryMinimal", "cvTemplateMinimalDescription"]],
  ["executive", ["cvTemplateExecutiveName", "cvTemplateCategoryExecutive", "cvTemplateExecutiveDescription"]],
  ["technical", ["cvTemplateTechnicalName", "cvTemplateCategoryTechnical", "cvTemplateTechnicalDescription"]],
  ["ats-classic", ["cvTemplateAtsClassicName", "cvTemplateCategoryAts", "cvTemplateAtsClassicDescription"]],
  ["nordic", ["cvTemplateNordicName", "cvTemplateCategoryModern", "cvTemplateNordicDescription"]],
  ["elegant", ["cvTemplateElegantName", "cvTemplateCategoryCreative", "cvTemplateElegantDescription"]],
  ["creative", ["cvTemplateCreativeName", "cvTemplateCategoryCreative", "cvTemplateCreativeDescription"]],
  ["code", ["cvTemplateCodeName", "cvTemplateCategoryTechnical", "cvTemplateCodeDescription"]],
]);

export default function CvTemplateGallery({ themes, selectedId, onSelect, previewHeight = 170, showDescriptions = true, disabled = false }: Props) {
  const { t, language } = useI18n();
  const id = useId();
  const [atsOnly, setAtsOnly] = useState(true);
  const visibleThemes = useMemo(() => getVisibleCvThemes(themes, atsOnly, selectedId), [atsOnly, selectedId, themes]);

  return (
    <Stack spacing={1.25}>
      <Stack direction="row" spacing={0.75} alignItems="center" flexWrap="wrap" useFlexGap>
        <Button size="small" disabled={disabled} aria-pressed={atsOnly} variant={atsOnly ? "contained" : "outlined"} onClick={() => setAtsOnly(true)}>{t("cvEditorAtsTemplates")}</Button>
        <Button size="small" disabled={disabled} aria-pressed={!atsOnly} variant={!atsOnly ? "contained" : "outlined"} onClick={() => setAtsOnly(false)}>{t("cvEditorAllTemplates")}</Button>
        {atsOnly && <Typography variant="caption" color="text.secondary">{t("cvEditorAtsTemplateHelp")}</Typography>}
      </Stack>
      <Box sx={{ display: "grid", gridTemplateColumns: "repeat(auto-fit, minmax(150px, 1fr))", gap: 1.25 }}>
        {visibleThemes.map((theme) => {
          const active = theme.id === selectedId;
          const locked = theme.available === false;
          const unavailable = locked || disabled;
          const labels = language === "nb" ? templateLabels.get(theme.id) : undefined;
          const name = labels ? t(labels[0]) : theme.name;
          return (
            <Paper key={theme.id} variant="outlined" role="button" tabIndex={unavailable ? -1 : 0} aria-label={name} aria-describedby={`${id}-${theme.id}-category ${showDescriptions ? `${id}-${theme.id}-description ` : ""}${id}-${theme.id}-features`} aria-disabled={unavailable} aria-pressed={active}
              onClick={() => { if (!unavailable) onSelect(theme); }}
              onKeyDown={(event) => { if (!unavailable && (event.key === "Enter" || event.key === " ")) { event.preventDefault(); onSelect(theme); } }}
              sx={{ p: 1, cursor: unavailable ? "not-allowed" : "pointer", position: "relative", minWidth: 0, overflowWrap: "anywhere", borderColor: active ? "primary.main" : "divider", borderWidth: active ? 2 : 1, "&:hover": unavailable ? undefined : { borderColor: "primary.main" } }}>
              {active && <CheckCircleIcon aria-label={t("cvEditorSelectedTemplate")} color="primary" sx={{ position: "absolute", zIndex: 2, top: 6, right: 6, bgcolor: "background.paper", borderRadius: "50%" }} />}
              <Box sx={{ mb: 1 }}><CvTemplateThumbnail theme={theme} height={previewHeight} /></Box>
              <Typography variant="body2" sx={{ fontWeight: 750 }}>{name}</Typography>
              <Typography id={`${id}-${theme.id}-category`} variant="caption" color="text.secondary" sx={{ display: "block" }}>{labels ? t(labels[1]) : theme.category}</Typography>
              {showDescriptions && <Typography id={`${id}-${theme.id}-description`} variant="caption" color="text.secondary" sx={{ display: "block", mt: 0.25, lineHeight: 1.35 }}>{labels ? t(labels[2]) : theme.description}</Typography>}
              <Stack id={`${id}-${theme.id}-features`} direction="row" spacing={0.5} alignItems="center" flexWrap="wrap" useFlexGap sx={{ mt: 0.75 }}>
                {theme.atsFriendly && <Chip size="small" label={t("cvEditorAtsFriendly")} color="success" variant="outlined" sx={{ height: 20, fontSize: 10 }} />}
                {theme.requiresPro && <Chip size="small" label={locked ? t("cvEditorPro") : t("cvEditorProUnlocked")} color="secondary" variant="outlined" sx={{ height: 20, fontSize: 10 }} />}
                <Stack direction="row" spacing={0.35} sx={{ ml: "auto" }} aria-hidden>
                  {theme.swatches.slice(0, 3).map((colour, index) => <Box key={`${colour}-${index}`} sx={{ width: 10, height: 10, borderRadius: "50%", bgcolor: colour, border: "1px solid", borderColor: "divider" }} />)}
                </Stack>
              </Stack>
            </Paper>
          );
        })}
      </Box>
    </Stack>
  );
}