import { router } from 'expo-router';
import React, { useState } from 'react';
import {
  ActivityIndicator, Pressable, RefreshControl, ScrollView, StyleSheet, Text,
  TextInput, View,
} from 'react-native';
import { useSafeAreaInsets } from 'react-native-safe-area-context';
import { clearCache } from '../lib/api';
import { C } from '../lib/theme';
import type { Priority } from '../lib/types';

/* Scrollable screen shell with pull-to-refresh (clears the API cache) */
export function Screen({
  children, onRefresh,
}: {
  children: React.ReactNode;
  onRefresh?: () => void;
}) {
  const insets = useSafeAreaInsets();
  const [refreshing, setRefreshing] = useState(false);
  return (
    <ScrollView
      style={{ flex: 1, backgroundColor: C.bg }}
      contentContainerStyle={{ padding: 16, paddingBottom: insets.bottom + 48 }}
      refreshControl={
        onRefresh ? (
          <RefreshControl
            refreshing={refreshing}
            tintColor={C.muted}
            colors={[C.accent]}
            progressBackgroundColor={C.surface2}
            onRefresh={() => {
              setRefreshing(true);
              clearCache();
              onRefresh();
              setTimeout(() => setRefreshing(false), 400);
            }}
          />
        ) : undefined
      }>
      {children}
    </ScrollView>
  );
}

export function Loading() {
  return (
    <View style={{ padding: 24, alignItems: 'center' }}>
      <ActivityIndicator color={C.muted} />
    </View>
  );
}

export function ErrBox({ msg }: { msg: string }) {
  return (
    <View style={s.errBox}>
      <Text style={{ color: C.red, fontSize: 13 }}>
        Could not load data — {msg}. Pull down to retry.
      </Text>
    </View>
  );
}

export function Sec({ title, count }: { title: string; count?: number | string }) {
  return (
    <Text style={s.sec}>
      {title.toUpperCase()}
      {count != null && <Text style={{ color: C.dim }}>  {count}</Text>}
    </Text>
  );
}

export function TileGrid({ children }: { children: React.ReactNode }) {
  return <View style={s.tiles}>{children}</View>;
}

export function Tile({
  label, value, unit, sub, delta, deltaTone,
}: {
  label: string;
  value: string;
  unit?: string;
  sub?: string;
  delta?: string;
  deltaTone?: 'good' | 'bad' | 'neutral';
}) {
  const toneColor = deltaTone === 'good' ? C.green : deltaTone === 'bad' ? C.red : C.muted;
  return (
    <View style={s.tile}>
      <Text style={s.tileLbl}>{label.toUpperCase()}</Text>
      <Text style={s.tileVal}>
        {value}
        {unit ? <Text style={s.tileUnit}> {unit}</Text> : null}
      </Text>
      {delta ? <Text style={{ fontSize: 11.5, marginTop: 5, color: toneColor }}>{delta}</Text> : null}
      {sub ? <Text style={s.tileSub}>{sub}</Text> : null}
    </View>
  );
}

/* Today-screen navigation card */
export function NavCard({
  title, big, unit, note, flagline, okline, href,
}: {
  title: string;
  big: string;
  unit?: string;
  note?: string;
  flagline?: string;
  okline?: string;
  href: string;
}) {
  return (
    <Pressable
      style={({ pressed }) => [s.navcard, pressed && { borderColor: C.accent }]}
      onPress={() => router.push(href as any)}>
      <View style={s.navHead}>
        <Text style={s.navT}>{title.toUpperCase()}</Text>
        <Text style={{ color: C.dim, fontSize: 13 }}>›</Text>
      </View>
      <Text style={s.navBig}>
        {big}
        {unit ? <Text style={s.tileUnit}> {unit}</Text> : null}
      </Text>
      {flagline ? <Text style={{ fontSize: 11.5, marginTop: 4, color: C.red }}>{flagline}</Text> : null}
      {okline ? <Text style={{ fontSize: 11.5, marginTop: 4, color: C.green }}>{okline}</Text> : null}
      {note ? (
        <Text numberOfLines={2} style={s.navNote}>
          {note}
        </Text>
      ) : null}
    </Pressable>
  );
}

export function Panel({
  title, sub, children,
}: {
  title?: string;
  sub?: string;
  children: React.ReactNode;
}) {
  return (
    <View style={s.panel}>
      {title ? (
        <View style={s.panelHead}>
          <Text style={{ color: C.text, fontSize: 13, fontWeight: '600' }}>{title}</Text>
          {sub ? <Text style={{ color: C.muted, fontSize: 11 }}>{sub}</Text> : null}
        </View>
      ) : null}
      {children}
    </View>
  );
}

export function PriorityCard({ p, rank }: { p: Priority; rank: number }) {
  const color = p.severity === 'flag' ? C.red : C.yellow;
  const border = p.severity === 'flag' ? 'rgba(255,69,58,0.35)' : 'rgba(245,197,66,0.35)';
  return (
    <View style={[s.priority, { borderColor: border }]}>
      <Text style={{ color, fontSize: 10.5, fontWeight: '700', marginBottom: 4 }}>
        #{rank} · {String(p.severity).toUpperCase()}
      </Text>
      <Text style={{ color: C.text, fontSize: 13.5, fontWeight: '600', marginBottom: 4 }}>
        {p.title}
      </Text>
      <Text style={{ color: C.muted, fontSize: 12, lineHeight: 17 }}>{p.detail}</Text>
    </View>
  );
}

export function SearchInput({
  value, onChange, placeholder,
}: {
  value: string;
  onChange: (v: string) => void;
  placeholder: string;
}) {
  return (
    <TextInput
      style={s.search}
      value={value}
      onChangeText={onChange}
      placeholder={placeholder}
      placeholderTextColor={C.dim}
      autoCapitalize="none"
      autoCorrect={false}
      clearButtonMode="while-editing"
    />
  );
}

export function SrcNote({ children }: { children: React.ReactNode }) {
  return <Text style={s.srcNote}>{children}</Text>;
}

export function LegendRow({ items }: { items: [string, string][] }) {
  return (
    <View style={{ flexDirection: 'row', flexWrap: 'wrap', gap: 14, marginTop: 10 }}>
      {items.map(([label, color]) => (
        <View key={label} style={{ flexDirection: 'row', alignItems: 'center', gap: 5 }}>
          <View style={{ width: 8, height: 8, borderRadius: 3, backgroundColor: color }} />
          <Text style={{ color: C.muted, fontSize: 11 }}>{label}</Text>
        </View>
      ))}
    </View>
  );
}

const s = StyleSheet.create({
  errBox: {
    borderWidth: 1, borderColor: 'rgba(255,69,58,0.3)', backgroundColor: C.redDim,
    borderRadius: 12, padding: 14, marginVertical: 12,
  },
  sec: {
    fontSize: 11, fontWeight: '600', letterSpacing: 0.8, color: C.muted,
    marginTop: 26, marginBottom: 10,
  },
  tiles: { flexDirection: 'row', flexWrap: 'wrap', gap: 10 },
  tile: {
    backgroundColor: C.surface, borderWidth: 1, borderColor: C.border, borderRadius: 14,
    padding: 14, flexBasis: '47%', flexGrow: 1,
  },
  tileLbl: { fontSize: 11, color: C.muted, letterSpacing: 0.5, marginBottom: 6 },
  tileVal: { fontSize: 24, fontWeight: '300', letterSpacing: -0.6, color: C.text },
  tileUnit: { fontSize: 12, color: C.muted, fontWeight: '400', letterSpacing: 0 },
  tileSub: { fontSize: 11.5, color: C.muted, marginTop: 5 },
  navcard: {
    backgroundColor: C.surface, borderWidth: 1, borderColor: C.border, borderRadius: 14,
    padding: 14, flexBasis: '47%', flexGrow: 1,
  },
  navHead: {
    flexDirection: 'row', justifyContent: 'space-between', alignItems: 'center', marginBottom: 8,
  },
  navT: { fontSize: 12, fontWeight: '600', color: C.muted, letterSpacing: 0.6 },
  navBig: { fontSize: 22, fontWeight: '300', letterSpacing: -0.5, color: C.text },
  navNote: { fontSize: 11.5, color: C.muted, marginTop: 4 },
  panel: {
    backgroundColor: C.surface, borderWidth: 1, borderColor: C.border, borderRadius: 14,
    padding: 14, marginBottom: 10,
  },
  panelHead: {
    flexDirection: 'row', justifyContent: 'space-between', alignItems: 'baseline', marginBottom: 10,
  },
  priority: {
    borderWidth: 1, borderRadius: 12, paddingVertical: 13, paddingHorizontal: 14,
    backgroundColor: C.surface, marginBottom: 8,
  },
  search: {
    paddingVertical: 10, paddingHorizontal: 14, borderRadius: 12, borderWidth: 1,
    borderColor: C.border, backgroundColor: C.surface, color: C.text, fontSize: 14,
    marginTop: 4, marginBottom: 12,
  },
  srcNote: { fontSize: 11, color: C.dim, marginTop: 12, lineHeight: 16 },
});