#!/bin/bash
SHADER_DIR="$HOME/.config/hypr/shaders"
ACTIVE_FILE="$SHADER_DIR/.active"

mapfile -t SHADERS < <(find "$SHADER_DIR" -name "*.glsl" | sort)

if [[ ${#SHADERS[@]} -eq 0 ]]; then
    exit 0
fi

INDEX=$(cat "$ACTIVE_FILE" 2>/dev/null)
[[ "$INDEX" =~ ^[0-9]+$ ]] || INDEX=-1

NEXT=$(( (INDEX + 1) % ${#SHADERS[@]} ))
echo "$NEXT" > "$ACTIVE_FILE"
hyprshade on "${SHADERS[$NEXT]}"