/**
 * Voice Floating Action Button Component
 *
 * Positioned at the center of the tab bar.
 * Shows different animations for each voice state:
 * - idle: white mic icon, green background
 * - listening: red background, expanding pulse rings
 * - processing: blue background, spinning indicator
 * - speaking: green background, wave-like pulse
 */

import React, { useRef, useEffect } from 'react';
import {
  StyleSheet,
  TouchableOpacity,
  Animated,
  ViewStyle,
  ActivityIndicator,
} from 'react-native';
import { Ionicons } from '@expo/vector-icons';
import * as Haptics from 'expo-haptics';
import { AppColors, BorderRadius } from '@/constants/theme';
import { useVoiceCall } from '@/contexts/VoiceCallContext';
import { useVoice } from '@/contexts/VoiceContext';

interface VoiceFABProps {
  onPress: () => void;
  style?: ViewStyle;
  disabled?: boolean;
  isListening?: boolean;
}

const FAB_SIZE = 60;

export function VoiceFAB({ onPress, style, disabled = false, isListening = false }: VoiceFABProps) {
  const { isCallActive } = useVoiceCall();
  const { status: voiceStatus } = useVoice();

  // Animation values
  const scale = useRef(new Animated.Value(1)).current;
  const opacity = useRef(new Animated.Value(1)).current;

  // Pulse ring 1 (main expanding ring)
  const pulse1Scale = useRef(new Animated.Value(1)).current;
  const pulse1Opacity = useRef(new Animated.Value(0)).current;

  // Pulse ring 2 (second ring, offset timing)
  const pulse2Scale = useRef(new Animated.Value(1)).current;
  const pulse2Opacity = useRef(new Animated.Value(0)).current;

  // Speaking glow animation
  const glowScale = useRef(new Animated.Value(1)).current;

  // Processing rotation
  const rotation = useRef(new Animated.Value(0)).current;

  // Store animation refs for cleanup
  const animationRef = useRef<Animated.CompositeAnimation | null>(null);

  // Determine effective state
  const effectiveStatus = isListening
    ? (voiceStatus === 'processing' ? 'processing' : voiceStatus === 'speaking' ? 'speaking' : 'listening')
    : 'idle';

  // Hide FAB when call is active
  useEffect(() => {
    if (isCallActive) {
      Animated.parallel([
        Animated.timing(scale, { toValue: 0, duration: 200, useNativeDriver: true }),
        Animated.timing(opacity, { toValue: 0, duration: 200, useNativeDriver: true }),
      ]).start();
    } else {
      Animated.parallel([
        Animated.spring(scale, { toValue: 1, friction: 5, tension: 40, useNativeDriver: true }),
        Animated.timing(opacity, { toValue: 1, duration: 200, useNativeDriver: true }),
      ]).start();
    }
  }, [isCallActive, scale, opacity]);

  // Animations based on voice status
  useEffect(() => {
    // Stop previous animation
    if (animationRef.current) {
      animationRef.current.stop();
      animationRef.current = null;
    }

    // Reset all animation values
    pulse1Scale.setValue(1);
    pulse1Opacity.setValue(0);
    pulse2Scale.setValue(1);
    pulse2Opacity.setValue(0);
    glowScale.setValue(1);
    rotation.setValue(0);

    if (effectiveStatus === 'listening') {
      // Double pulse ring animation - more active/dynamic
      const pulseAnim = Animated.loop(
        Animated.stagger(500, [
          Animated.parallel([
            Animated.timing(pulse1Scale, { toValue: 2.0, duration: 1200, useNativeDriver: true }),
            Animated.timing(pulse1Opacity, { toValue: 0, duration: 1200, useNativeDriver: true }),
          ]),
          Animated.parallel([
            Animated.timing(pulse1Scale, { toValue: 1, duration: 0, useNativeDriver: true }),
            Animated.timing(pulse1Opacity, { toValue: 0.5, duration: 0, useNativeDriver: true }),
          ]),
        ])
      );

      const pulse2Anim = Animated.loop(
        Animated.sequence([
          Animated.delay(400),
          Animated.parallel([
            Animated.timing(pulse2Scale, { toValue: 1.8, duration: 1200, useNativeDriver: true }),
            Animated.timing(pulse2Opacity, { toValue: 0, duration: 1200, useNativeDriver: true }),
          ]),
          Animated.parallel([
            Animated.timing(pulse2Scale, { toValue: 1, duration: 0, useNativeDriver: true }),
            Animated.timing(pulse2Opacity, { toValue: 0.4, duration: 0, useNativeDriver: true }),
          ]),
        ])
      );

      const combined = Animated.parallel([pulseAnim, pulse2Anim]);
      animationRef.current = combined;
      combined.start();

    } else if (effectiveStatus === 'speaking') {
      // Gentle breathing glow when speaking
      const glowAnim = Animated.loop(
        Animated.sequence([
          Animated.timing(glowScale, { toValue: 1.15, duration: 600, useNativeDriver: true }),
          Animated.timing(glowScale, { toValue: 1.0, duration: 600, useNativeDriver: true }),
        ])
      );

      // Soft outer glow
      const softPulse = Animated.loop(
        Animated.sequence([
          Animated.parallel([
            Animated.timing(pulse1Scale, { toValue: 1.4, duration: 800, useNativeDriver: true }),
            Animated.timing(pulse1Opacity, { toValue: 0.3, duration: 400, useNativeDriver: true }),
          ]),
          Animated.parallel([
            Animated.timing(pulse1Scale, { toValue: 1.0, duration: 800, useNativeDriver: true }),
            Animated.timing(pulse1Opacity, { toValue: 0, duration: 400, useNativeDriver: true }),
          ]),
        ])
      );

      const combined = Animated.parallel([glowAnim, softPulse]);
      animationRef.current = combined;
      combined.start();

    } else if (effectiveStatus === 'processing') {
      // Spinning rotation for processing
      const spinAnim = Animated.loop(
        Animated.timing(rotation, { toValue: 1, duration: 1500, useNativeDriver: true })
      );
      animationRef.current = spinAnim;
      spinAnim.start();
    }

    return () => {
      if (animationRef.current) {
        animationRef.current.stop();
        animationRef.current = null;
      }
    };
  }, [effectiveStatus]); // eslint-disable-line react-hooks/exhaustive-deps

  // Press animation with haptic feedback
  const handlePressIn = () => {
    Haptics.impactAsync(Haptics.ImpactFeedbackStyle.Medium);
    Animated.spring(scale, { toValue: 0.85, friction: 5, useNativeDriver: true }).start();
  };

  const handlePressOut = () => {
    Animated.spring(scale, { toValue: 1, friction: 5, useNativeDriver: true }).start();
  };

  if (isCallActive) {
    return null;
  }

  // Determine colors and icon based on state
  let fabBgColor = AppColors.success; // idle: green
  let iconName: 'mic-outline' | 'mic' | 'volume-high' = 'mic-outline';
  let pulseColor = AppColors.error;

  if (effectiveStatus === 'listening') {
    fabBgColor = '#FF3B30'; // red
    iconName = 'mic';
    pulseColor = '#FF3B30';
  } else if (effectiveStatus === 'processing') {
    fabBgColor = AppColors.primary; // blue
    iconName = 'mic';
    pulseColor = AppColors.primary;
  } else if (effectiveStatus === 'speaking') {
    fabBgColor = '#34C759'; // green
    iconName = 'volume-high';
    pulseColor = '#34C759';
  }

  const spin = rotation.interpolate({
    inputRange: [0, 1],
    outputRange: ['0deg', '360deg'],
  });

  return (
    <Animated.View
      style={[
        styles.container,
        {
          transform: [{ scale }],
          opacity,
        },
        style,
      ]}
    >
      {/* Pulse ring 1 */}
      {(effectiveStatus === 'listening' || effectiveStatus === 'speaking') && (
        <Animated.View
          style={[
            styles.pulseRing,
            {
              backgroundColor: pulseColor,
              transform: [{ scale: pulse1Scale }],
              opacity: pulse1Opacity,
            },
          ]}
        />
      )}

      {/* Pulse ring 2 (listening only) */}
      {effectiveStatus === 'listening' && (
        <Animated.View
          style={[
            styles.pulseRing,
            {
              backgroundColor: pulseColor,
              transform: [{ scale: pulse2Scale }],
              opacity: pulse2Opacity,
            },
          ]}
        />
      )}

      <Animated.View
        style={[
          { transform: [{ scale: effectiveStatus === 'speaking' ? glowScale : 1 }] },
        ]}
      >
        <TouchableOpacity
          style={[
            styles.fab,
            { backgroundColor: disabled ? AppColors.surface : fabBgColor },
            disabled && styles.fabDisabled,
          ]}
          onPress={onPress}
          onPressIn={handlePressIn}
          onPressOut={handlePressOut}
          disabled={disabled}
          activeOpacity={0.9}
        >
          {effectiveStatus === 'processing' ? (
            <Animated.View style={{ transform: [{ rotate: spin }] }}>
              <ActivityIndicator size="small" color={AppColors.white} />
            </Animated.View>
          ) : (
            <Ionicons
              name={iconName}
              size={28}
              color={disabled ? AppColors.textMuted : AppColors.white}
            />
          )}
        </TouchableOpacity>
      </Animated.View>
    </Animated.View>
  );
}

const styles = StyleSheet.create({
  container: {
    alignItems: 'center',
    justifyContent: 'center',
  },
  pulseRing: {
    position: 'absolute',
    width: FAB_SIZE,
    height: FAB_SIZE,
    borderRadius: FAB_SIZE / 2,
  },
  fab: {
    width: FAB_SIZE,
    height: FAB_SIZE,
    borderRadius: FAB_SIZE / 2,
    justifyContent: 'center',
    alignItems: 'center',
    shadowColor: '#000',
    shadowOffset: { width: 0, height: 4 },
    shadowOpacity: 0.3,
    shadowRadius: 8,
    elevation: 8,
  },
  fabDisabled: {
    shadowOpacity: 0.1,
  },
});