import { router } from "expo-router";
import { ScrollView, View } from "react-native";
import { useTranslation } from "react-i18next";
import { Badge } from "@/components/ui/Badge";
import { Button } from "@/components/ui/Button";
import { Card } from "@/components/ui/Card";
import { EmptyState } from "@/components/ui/EmptyState";
import { AppHeader } from "@/components/ui/Header";
import { Screen } from "@/components/ui/Screen";
import { Text } from "@/components/ui/Text";
import { usePrescriptionStore } from "@/lib/stores/prescriptionStore";
import { colors, gutter } from "@/lib/theme";
import { routes } from "@/lib/routes";

const statusTone = {
  submitted: "neutral",
  under_review: "warn",
  approved: "brand",
  queried: "info",
  rejected: "danger",
  filled: "brand",
} as const;

export default function RxListScreen() {
  const { t } = useTranslation();
  const prescriptions = usePrescriptionStore((s) => s.prescriptions);

  return (
    <Screen>
      <AppHeader
        title={t("common.prescriptions")}
        subtitle="Scan, track status, refill and remind"
      />
      <ScrollView
        contentContainerStyle={{
          paddingHorizontal: gutter,
          paddingBottom: 40,
        }}
      >
        <Button
          title={t("common.scanRx")}
          icon="scan-outline"
          onPress={() => router.push(routes.rxScan)}
        />

        {prescriptions.length === 0 ? (
          <EmptyState
            icon="document-text-outline"
            title="No prescriptions yet"
            body="Scan or upload a prescription to get started."
            actionTitle="Scan prescription"
            onAction={() => router.push(routes.rxScan)}
          />
        ) : (
          <View style={{ marginTop: 16, gap: 12 }}>
            {prescriptions.map((rx) => {
              const dueIn = (() => {
                if (!rx.lastFilledAt) return null;
                const due = new Date(rx.lastFilledAt);
                due.setDate(due.getDate() + rx.daysSupply);
                return Math.ceil((due.getTime() - Date.now()) / (1000 * 60 * 60 * 24));
              })();

              return (
                <Card key={rx.id} onPress={() => router.push(routes.rxDetail(rx.id))}>
                  <View
                    style={{
                      flexDirection: "row",
                      justifyContent: "space-between",
                      gap: 12,
                    }}
                  >
                    <View style={{ flex: 1 }}>
                      <Text variant="h3">{rx.medicineName}</Text>
                      <Text variant="caption" color={colors.subtle} style={{ marginTop: 4 }}>
                        {rx.patientName} · {rx.medicines.length} item
                        {rx.medicines.length === 1 ? "" : "s"}
                      </Text>
                    </View>
                    <Badge
                      label={rx.status.replace("_", " ")}
                      tone={statusTone[rx.status]}
                    />
                  </View>
                  {dueIn !== null ? (
                    <Text
                      variant="label"
                      color={dueIn <= 3 ? colors.warn : colors.brandText}
                      style={{ marginTop: 10 }}
                    >
                      {dueIn <= 0 ? "Refill overdue" : `Refill in ${dueIn} days`}
                    </Text>
                  ) : (
                    <Text variant="label" color={colors.warn} style={{ marginTop: 10 }}>
                      Waiting for first fill
                    </Text>
                  )}
                  <Text variant="caption" color={colors.subtle} style={{ marginTop: 8 }}>
                    Tap for details, reminders and reorder
                  </Text>
                </Card>
              );
            })}
          </View>
        )}
      </ScrollView>
    </Screen>
  );
}