import type React from 'react';
import { useCallback, useEffect, useRef, useState } from 'react';

import styled, { type DefaultTheme } from 'styled-components';

export interface RangeSliderProps {
  min: number;
  max: number;
  step?: number;
  value: [number, number];
  onChange: (value: [number, number]) => void;
  disabled?: boolean;
  showValues?: boolean;
  formatValue?: (value: number) => string;
}

const Container = styled.div`
  width: 100%;
  padding: ${(props: { theme: DefaultTheme }) => props.theme.spacing.md} 0;
`;

const Track = styled.div`
  position: relative;
  height: 6px;
  background: ${(props: { theme: DefaultTheme }) => props.theme.colors.surface};
  border-radius: ${(props: { theme: DefaultTheme }) => props.theme.borderRadius.full};
  margin: ${(props: { theme: DefaultTheme }) => props.theme.spacing.md} 0;
`;

const Range = styled.div<{ $left: number; $width: number }>`
  position: absolute;
  height: 100%;
  background: ${(props: { theme: DefaultTheme }) => props.theme.colors.primary};
  border-radius: ${(props: { theme: DefaultTheme }) => props.theme.borderRadius.full};
  left: ${(props) => props.$left}%;
  width: ${(props) => props.$width}%;
`;

const Thumb = styled.div<{ $position: number; $disabled?: boolean }>`
  position: absolute;
  width: 20px;
  height: 20px;
  background: ${(props: { theme: DefaultTheme }) => props.theme.colors.primary};
  border: 3px solid white;
  border-radius: 50%;
  top: 50%;
  left: ${(props) => props.$position}%;
  transform: translate(-50%, -50%);
  cursor: ${(props) => (props.$disabled ? 'not-allowed' : 'grab')};
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  transition: transform 0.1s;

  &:hover {
    transform: translate(-50%, -50%) scale(1.1);
  }

  &:active {
    cursor: ${(props) => (props.$disabled ? 'not-allowed' : 'grabbing')};
    transform: translate(-50%, -50%) scale(1.15);
  }
`;

const Values = styled.div`
  display: flex;
  justify-content: space-between;
  margin-top: ${(props: { theme: DefaultTheme }) => props.theme.spacing.sm};
  font-size: ${(props: { theme: DefaultTheme }) => props.theme.typography.fontSize.sm};
  color: ${(props: { theme: DefaultTheme }) => props.theme.colors.text.secondary};
`;

const ValueLabel = styled.div`
  font-weight: ${(props: { theme: DefaultTheme }) => props.theme.typography.fontWeight.semibold};
  color: ${(props: { theme: DefaultTheme }) => props.theme.colors.text};
`;

export const RangeSlider: FC<RangeSliderProps> = ({
  min,
  max,
  step = 1,
  value,
  onChange,
  disabled = false,
  showValues = true,
  formatValue = (val) => val.toString(),
}) => {
  const trackRef = useRef<HTMLDivElement>(null);
  const [dragging, setDragging] = useState<'min' | 'max' | null>(null);

  const getPercentage = (val: number) => ((val - min) / (max - min)) * 100;

  const getValueFromPosition = useCallback(
    (clientX: number): number => {
      if (!trackRef.current) {
        return min;
      }

      const rect = trackRef.current.getBoundingClientRect();
      const percentage = (clientX - rect.left) / rect.width;
      const rawValue = min + percentage * (max - min);

      // Round to step
      const steppedValue = Math.round(rawValue / step) * step;

      // Clamp to min/max
      return Math.max(min, Math.min(max, steppedValue));
    },
    [min, max, step],
  );

  const handleMouseMove = useCallback(
    (e: MouseEvent) => {
      if (!dragging) {
        return;
      }

      const newValue = getValueFromPosition(e.clientX);

      if (dragging === 'min') {
        // Don't let min thumb pass max thumb
        onChange([Math.min(newValue, value[1] - step), value[1]]);
      } else {
        // Don't let max thumb pass min thumb
        onChange([value[0], Math.max(newValue, value[0] + step)]);
      }
    },
    [dragging, getValueFromPosition, onChange, value, step],
  );

  const handleMouseUp = useCallback(() => {
    setDragging(null);
  }, []);

  const handleMouseDown = (thumb: 'min' | 'max') => {
    if (!disabled) {
      setDragging(thumb);
    }
  };

  useEffect(() => {
    if (!dragging) {
      return;
    }

    document.addEventListener('mousemove', handleMouseMove);
    document.addEventListener('mouseup', handleMouseUp);

    return () => {
      document.removeEventListener('mousemove', handleMouseMove);
      document.removeEventListener('mouseup', handleMouseUp);
    };
  }, [dragging, handleMouseMove, handleMouseUp]);

  const minPercent = getPercentage(value[0]);
  const maxPercent = getPercentage(value[1]);

  return (
    <Container>
      <Track ref={trackRef}>
        <Range $left={minPercent} $width={maxPercent - minPercent} />
        <Thumb
          $position={minPercent}
          $disabled={disabled}
          onMouseDown={() => handleMouseDown('min')}
        />
        <Thumb
          $position={maxPercent}
          $disabled={disabled}
          onMouseDown={() => handleMouseDown('max')}
        />
      </Track>

      {showValues && (
        <Values>
          <ValueLabel>{formatValue(value[0])}</ValueLabel>
          <ValueLabel>{formatValue(value[1])}</ValueLabel>
        </Values>
      )}
    </Container>
  );
};