import React, { useState, useRef, useCallback, useEffect } from "react";
import {
  View,
  Text,
  StyleSheet,
  TouchableOpacity,
  TouchableWithoutFeedback,
  Modal,
  Platform,
  useWindowDimensions,
} from "react-native";
import { Ionicons } from "@expo/vector-icons";
import { useTheme } from "../utils/theme";

interface Props {
  hlsUrl: string;
  flvUrl?: string;
  isLive: boolean;
  qualities?: { qn: number; desc: string }[];
  currentQn?: number;
  onQualityChange?: (qn: number) => void;
}

const HIDE_DELAY = 3000;

const HEADERS = {};

export function LivePlayer({
  hlsUrl,
  flvUrl,
  isLive,
  qualities = [],
  currentQn = 0,
  onQualityChange,
}: Props) {
  const { width: SCREEN_W, height: SCREEN_H } = useWindowDimensions();
  const VIDEO_H = SCREEN_W * 0.5625;

  if (Platform.OS === "web") {
    return (
      <View style={[styles.container, { width: SCREEN_W, height: VIDEO_H }]}>
        <Text style={styles.webHint}>请在手机端观看直播</Text>
      </View>
    );
  }

  if (!isLive || !hlsUrl) {
    return (
      <View style={[styles.container, { width: SCREEN_W, height: VIDEO_H }]}>
        <Ionicons name="tv-outline" size={40} color="#555" />
        <Text style={styles.offlineText}>暂未开播</Text>
      </View>
    );
  }

  return (
    <NativeLivePlayer
      hlsUrl={hlsUrl}
      screenW={SCREEN_W}
      screenH={SCREEN_H}
      videoH={VIDEO_H}
      qualities={qualities}
      currentQn={currentQn}
      onQualityChange={onQualityChange}
    />
  );
}

function NativeLivePlayer({
  hlsUrl,
  screenW,
  screenH,
  videoH,
  qualities,
  currentQn,
  onQualityChange,
}: {
  hlsUrl: string;
  screenW: number;
  screenH: number;
  videoH: number;
  qualities: { qn: number; desc: string }[];
  currentQn: number;
  onQualityChange?: (qn: number) => void;
}) {
  const Video = require("react-native-video").default;
  const theme = useTheme();

  const [showControls, setShowControls] = useState(true);
  const [paused, setPaused] = useState(false);
  const [isFullscreen, setIsFullscreen] = useState(false);
  const [buffering, setBuffering] = useState(true);
  const [showQualityPanel, setShowQualityPanel] = useState(false);
  const hideTimer = useRef<ReturnType<typeof setTimeout> | null>(null);
  const videoRef = useRef<any>(null);
  const currentTimeRef = useRef(0);

  const resetHideTimer = useCallback(() => {
    if (hideTimer.current) clearTimeout(hideTimer.current);
    hideTimer.current = setTimeout(() => setShowControls(false), HIDE_DELAY);
  }, []);

  useEffect(() => {
    resetHideTimer();
    return () => {
      if (hideTimer.current) clearTimeout(hideTimer.current);
    };
  }, []);

  // Lock/unlock orientation on fullscreen toggle
  useEffect(() => {
    (async () => {
      try {
        const ScreenOrientation = require("expo-screen-orientation");
        if (isFullscreen) {
          await ScreenOrientation.lockAsync(
            ScreenOrientation.OrientationLock.LANDSCAPE_RIGHT,
          );
        } else {
          await ScreenOrientation.lockAsync(
            ScreenOrientation.OrientationLock.PORTRAIT_UP,
          );
        }
      } catch {
        /* graceful degradation in Expo Go */
      }
    })();
  }, [isFullscreen]);

  // Restore portrait on unmount
  useEffect(() => {
    return () => {
      (async () => {
        try {
          const ScreenOrientation = require("expo-screen-orientation");
          await ScreenOrientation.lockAsync(
            ScreenOrientation.OrientationLock.PORTRAIT_UP,
          );
        } catch {
          /* ignore */
        }
      })();
    };
  }, []);

  const handleTap = useCallback(() => {
    setShowControls((prev) => {
      if (!prev) {
        resetHideTimer();
        return true;
      }
      if (hideTimer.current) clearTimeout(hideTimer.current);
      return false;
    });
  }, [resetHideTimer]);

  const fsW = Math.max(screenW, screenH);
  const fsH = Math.min(screenW, screenH);
  const containerStyle = isFullscreen
    ? { position: 'absolute' as const, top: 0, left: 0, width: fsW, height: fsH, zIndex: 999, elevation: 999 }
    : { width: screenW, height: videoH };

  const currentQnDesc = qualities.find((q) => q.qn === currentQn)?.desc ?? "";

  const videoContent = (
    <View style={[styles.container, containerStyle]}>
      <Video
        key={hlsUrl}
        ref={videoRef}
        source={{ uri: hlsUrl, headers: HEADERS }}
        style={StyleSheet.absoluteFill}
        resizeMode="contain"
        controls={false}
        paused={paused}
        onProgress={({ currentTime: ct }: { currentTime: number }) => {
          currentTimeRef.current = ct;
        }}
        onBuffer={({ isBuffering }: { isBuffering: boolean }) =>
          setBuffering(isBuffering)
        }
        onLoad={() => {
          setBuffering(false);
          if (currentTimeRef.current > 0) {
            videoRef.current?.seek(currentTimeRef.current);
          }
        }}
      />

      {buffering && (
        <View style={styles.bufferingOverlay} pointerEvents="none">
          <Text style={styles.bufferingText}>缓冲中...</Text>
        </View>
      )}

      <TouchableWithoutFeedback onPress={handleTap}>
        <View style={StyleSheet.absoluteFill} />
      </TouchableWithoutFeedback>

      {showControls && (
        <>
          {/* Center play/pause */}
          <TouchableOpacity
            style={styles.centerBtn}
            onPress={() => {
              setPaused((p) => !p);
              resetHideTimer();
            }}
          >
            <View style={styles.centerBtnBg}>
              <Ionicons
                name={paused ? "play" : "pause"}
                size={28}
                color="#fff"
              />
            </View>
          </TouchableOpacity>

          {/* Bottom controls */}
          <View style={styles.bottomBar}>
            <TouchableOpacity
              style={styles.ctrlBtn}
              onPress={() => {
                setPaused((p) => !p);
                resetHideTimer();
              }}
            >
              <Ionicons
                name={paused ? "play" : "pause"}
                size={16}
                color="#fff"
              />
            </TouchableOpacity>
            <View style={{ flex: 1 }} />
            {qualities.length > 0 && (
              <TouchableOpacity
                style={styles.qualityBtn}
                onPress={() => {
                  setShowQualityPanel(true);
                  resetHideTimer();
                }}
              >
                <Text style={styles.qualityText}>
                  {currentQnDesc || "清晰度"}
                </Text>
              </TouchableOpacity>
            )}
            <TouchableOpacity
              style={styles.ctrlBtn}
              onPress={() => {
                if (isFullscreen) setPaused(true);
                setIsFullscreen((fs) => !fs);
                resetHideTimer();
              }}
            >
              <Ionicons
                name={isFullscreen ? "contract" : "expand"}
                size={16}
                color="#fff"
              />
            </TouchableOpacity>
          </View>
        </>
      )}

      {/* Quality selector panel */}
      <Modal
        visible={showQualityPanel}
        transparent
        animationType="fade"
        onRequestClose={() => setShowQualityPanel(false)}
      >
        <TouchableOpacity
          style={styles.qualityOverlay}
          activeOpacity={1}
          onPress={() => setShowQualityPanel(false)}
        >
          <TouchableOpacity activeOpacity={1} onPress={() => {}}>
            <View style={[styles.qualityPanel, { backgroundColor: theme.modalBg }]}>
              <Text style={[styles.qualityPanelTitle, { color: theme.modalText }]}>清晰度</Text>
              {qualities.map((q) => (
                <TouchableOpacity
                  key={q.qn}
                  style={[styles.qualityItem, { borderTopColor: theme.modalBorder }]}
                  onPress={() => {
                    onQualityChange?.(q.qn);
                    setShowQualityPanel(false);
                  }}
                >
                  <Text
                    style={[
                      styles.qualityItemText,
                      { color: theme.modalTextSub },
                      currentQn === q.qn && styles.qualityItemTextActive,
                    ]}
                  >
                    {q.desc}
                  </Text>
                  {currentQn === q.qn && (
                    <Ionicons name="checkmark" size={14} color="#00AEEC" />
                  )}
                </TouchableOpacity>
              ))}
            </View>
          </TouchableOpacity>
        </TouchableOpacity>
      </Modal>
    </View>
  );

  return videoContent;
}

const styles = StyleSheet.create({
  container: {
    backgroundColor: "#000",
    alignItems: "center",
    justifyContent: "center",
  },
  webHint: { color: "#fff", fontSize: 15 },
  offlineText: { color: "#999", fontSize: 14, marginTop: 10 },
  bufferingOverlay: {
    ...StyleSheet.absoluteFillObject,
    alignItems: "center",
    justifyContent: "center",
  },
  bufferingText: { color: "#fff", fontSize: 13, opacity: 0.8 },
  liveBadge: {
    position: "absolute",
    top: 10,
    left: 12,
    flexDirection: "row",
    alignItems: "center",
    backgroundColor: "rgba(0,0,0,0.5)",
    paddingHorizontal: 8,
    paddingVertical: 3,
    borderRadius: 4,
  },
  liveDot: {
    width: 6,
    height: 6,
    borderRadius: 3,
    backgroundColor: "#f00",
    marginRight: 5,
  },
  liveText: {
    color: "#fff",
    fontSize: 11,
    fontWeight: "700",
    letterSpacing: 1,
  },
  centerBtn: {
    position: "absolute",
    top: "50%",
    left: "50%",
    transform: [{ translateX: -28 }, { translateY: -28 }],
  },
  centerBtnBg: {
    width: 56,
    height: 56,
    borderRadius: 28,
    backgroundColor: "rgba(0,0,0,0.45)",
    alignItems: "center",
    justifyContent: "center",
  },
  bottomBar: {
    position: "absolute",
    bottom: 0,
    left: 0,
    right: 0,
    flexDirection: "row",
    alignItems: "center",
    paddingHorizontal: 8,
    paddingBottom: 8,
    paddingTop: 24,
    backgroundColor: "rgba(0,0,0,0)",
  },
  ctrlBtn: { paddingHorizontal: 8, paddingVertical: 4 },
  qualityBtn: {
    paddingHorizontal: 8,
    paddingVertical: 4,
    backgroundColor: "rgba(0,0,0,0.4)",
    borderRadius: 4,
    marginRight: 4,
  },
  qualityText: { color: "#fff", fontSize: 11, fontWeight: "600" },
  qualityOverlay: {
    flex: 1,
    backgroundColor: "rgba(0,0,0,0.5)",
    justifyContent: "center",
    alignItems: "center",
  },
  qualityPanel: {
    backgroundColor: "#fff",
    borderRadius: 12,
    paddingVertical: 8,
    paddingHorizontal: 16,
    minWidth: 180,
  },
  qualityPanelTitle: {
    fontSize: 15,
    fontWeight: "700",
    color: "#212121",
    paddingVertical: 10,
    textAlign: "center",
  },
  qualityItem: {
    flexDirection: "row",
    alignItems: "center",
    justifyContent: "space-between",
    paddingVertical: 12,
    borderTopWidth: StyleSheet.hairlineWidth,
    borderTopColor: "#eee",
  },
  qualityItemText: { fontSize: 14, color: "#333" },
  qualityItemTextActive: { color: "#00AEEC", fontWeight: "700" },
});