oximedia-scene 0.1.2

//! Depth cues and perspective analysis.

use crate::error::{SceneError, SceneResult};
use serde::{Deserialize, Serialize};

/// Depth cues detected in image.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DepthCues {
    /// Perspective lines detected (0.0-1.0).
    pub perspective: f32,
    /// Size gradient (foreground to background, 0.0-1.0).
    pub size_gradient: f32,
    /// Atmospheric perspective (clarity variation, 0.0-1.0).
    pub atmospheric: f32,
    /// Occlusion detected (0.0-1.0).
    pub occlusion: f32,
}

/// Depth analyzer.
pub struct DepthAnalyzer;

impl DepthAnalyzer {
    /// Create a new depth analyzer.
    #[must_use]
    pub fn new() -> Self {
        Self
    }

    /// Analyze depth cues.
    ///
    /// # Errors
    ///
    /// Returns error if analysis fails.
    pub fn analyze(&self, rgb_data: &[u8], width: usize, height: usize) -> SceneResult<DepthCues> {
        if rgb_data.len() != width * height * 3 {
            return Err(SceneError::InvalidDimensions(
                "RGB data size mismatch".to_string(),
            ));
        }

        let perspective = self.detect_perspective(rgb_data, width, height);
        let size_gradient = self.detect_size_gradient(rgb_data, width, height);
        let atmospheric = self.detect_atmospheric_perspective(rgb_data, width, height);
        let occlusion = 0.5; // Simplified

        Ok(DepthCues {
            perspective,
            size_gradient,
            atmospheric,
            occlusion,
        })
    }

    fn detect_perspective(&self, _rgb_data: &[u8], _width: usize, _height: usize) -> f32 {
        // Simplified: would use line detection and vanishing point analysis
        0.5
    }

    fn detect_size_gradient(&self, _rgb_data: &[u8], _width: usize, _height: usize) -> f32 {
        // Simplified: would analyze object sizes from top to bottom
        0.5
    }

    fn detect_atmospheric_perspective(&self, rgb_data: &[u8], width: usize, height: usize) -> f32 {
        // Analyze contrast/clarity gradient from top to bottom
        let strip_height = height / 4;
        let mut top_clarity = 0.0;
        let mut bottom_clarity = 0.0;

        for y in 0..strip_height {
            for x in 1..width {
                let idx = (y * width + x) * 3;
                let prev_idx = (y * width + (x - 1)) * 3;
                for c in 0..3 {
                    top_clarity += (rgb_data[idx + c] as i32 - rgb_data[prev_idx + c] as i32)
                        .unsigned_abs() as f32;
                }
            }
        }

        for y in (height - strip_height)..height {
            for x in 1..width {
                let idx = (y * width + x) * 3;
                let prev_idx = (y * width + (x - 1)) * 3;
                for c in 0..3 {
                    bottom_clarity += (rgb_data[idx + c] as i32 - rgb_data[prev_idx + c] as i32)
                        .unsigned_abs() as f32;
                }
            }
        }

        let pixels = strip_height * (width - 1);
        if pixels > 0 {
            let top_avg = top_clarity / pixels as f32;
            let bottom_avg = bottom_clarity / pixels as f32;
            ((top_avg - bottom_avg).abs() / 255.0).clamp(0.0, 1.0)
        } else {
            0.0
        }
    }
}

impl Default for DepthAnalyzer {
    fn default() -> Self {
        Self::new()
    }
}