shader_type canvas_item;

uniform bool time_slowed = false;
uniform float effect_mixture : hint_range(0.0, 1.0) = 0.0;
uniform float alpha_multiplier = 1.0;
uniform float color_offset = 0.0;  // 颜色偏移值

uniform float glow_intensity = 1.2;
uniform float inner_glow_width = 0.5;
uniform float outer_glow_width = 2.0;
uniform float pulse_speed = 2.0;
uniform float pulse_strength = 0.2;
uniform bool high_quality = true;  // 性能开关

// HSV转RGB函数
vec3 hsv2rgb(vec3 c) {
    vec4 K = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
    vec3 p = abs(fract(c.xxx + K.xyz) * 6.0 - K.www);
    return c.z * mix(K.xxx, clamp(p - K.xxx, 0.0, 1.0), c.y);
}

void fragment() {
    vec4 texture_color = texture(TEXTURE, UV);

    if (texture_color.a > 0.0) {
        vec3 blue_base = vec3(0.2, 0.6, 1.5);
        float luminance = dot(texture_color.rgb, vec3(0.299, 0.587, 0.114));

        // 脉冲动画效果
        float pulse = (sin(TIME * pulse_speed) * 0.5 + 0.5) * pulse_strength;

        // 内发光效果
        float inner_glow = pow(luminance, inner_glow_width) * glow_intensity;

        // 外发光效果
        float outer_glow = 0.0;
        if (high_quality) {
            // 高质量模式 - 完整采样
            vec2 size = 1.0 / TEXTURE_PIXEL_SIZE;
            vec2 pixel_size = 1.0 / size;
            for(float x = -outer_glow_width; x <= outer_glow_width; x += 1.0) {
                for(float y = -outer_glow_width; y <= outer_glow_width; y += 1.0) {
                    vec2 offset = vec2(x, y) * pixel_size;
                    float sample_alpha = texture(TEXTURE, UV + offset).a;
                    float distance = length(vec2(x, y)) / outer_glow_width;
                    outer_glow += sample_alpha * (1.0 - distance);
                }
            }
            outer_glow = outer_glow / (outer_glow_width * outer_glow_width * 4.0);
        } else {
            // 性能模式 - 简化采样
            float sample_distance = outer_glow_width * 0.5;
            vec2 pixel_size = 1.0 / (1.0 / TEXTURE_PIXEL_SIZE);
            for(float i = 0.0; i < 4.0; i++) {
                float angle = i * PI * 0.5;
                vec2 offset = vec2(cos(angle), sin(angle)) * sample_distance * pixel_size;
                outer_glow += texture(TEXTURE, UV + offset).a;
            }
            outer_glow = outer_glow * 0.25;
        }

        float total_glow = inner_glow + outer_glow + pulse;

        // 基于color_offset生成颜色，范围集中在黄色系
        float hue = fract(color_offset) * 0.4 + 0.1;  // 0.1-0.5范围，集中在黄色区域
        vec3 rainbow_color = hsv2rgb(vec3(hue, 0.9, 0.95));  // 高饱和度，稍微降低亮度

        // 混合发光效果
        vec3 final_color = mix(blue_base, rainbow_color, total_glow);
        final_color += rainbow_color * total_glow * 0.5;

        // 最终颜色混合
        vec3 mixed_color = mix(texture_color.rgb, final_color, effect_mixture);
        COLOR = vec4(mixed_color, texture_color.a * alpha_multiplier);
    } else {
        COLOR = vec4(texture_color.rgb, texture_color.a * alpha_multiplier);
    }
}