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/**
 * Date: 2024/05/09
 * This code creates a radar-like display using Processing, receiving data from a serial port.
 */

import processing.serial.*;

Serial communicationPort;    // Serial communication port
String serialData = "";      // Variable to store serial data
float scanAngle = 0;         // Variable to store scan angle
float scanDistance = 0;      // Variable to store scan distance
int radarRadius = 800;       // Radar radius
int maxDistance = 40;        // Maximum display distance in cm

void setup() {
    size(1920, 1080);                // Set the size of the window
    smooth();                        // Enable anti-aliasing
    String portName = Serial.list()[0]; // Get the first serial port (adjust index as needed)
    communicationPort = new Serial(this, portName, 9600); // Initialize serial communication
    communicationPort.bufferUntil('.'); // Set the buffer until '.' character
    background(0);                   // Set the background to black
}

void draw() {
    drawRadarBackground(); // Draw the radar background
    if (serialData.length() > 0) {
        parseSerialData(); // Parse the incoming serial data
        drawDetection();   // Draw the detected object
    }
    displayInfo(scanDistance, scanAngle); // Update display information
}

void drawRadarBackground() {
    pushMatrix();
    translate(width / 2, height - 200); // Position the radar
    noFill();
    stroke(80);            // Gray grid lines
    strokeWeight(1);
    for (int i = 0; i < 5; i++) {
        float r = radarRadius * (i + 1) / 5.0;
        arc(0, 0, r * 2, r * 2, PI, TWO_PI); // Draw radar arcs
    }
    for (int i = 0; i < 180; i += 10) {
        float x = radarRadius * cos(radians(i));
        float y = radarRadius * sin(radians(i));
        line(0, 0, x, -y); // Draw radar lines
        if (i % 30 == 0) {
            fill(255);
            textSize(16);
            text(i + "°", x + 5, -y + 5); // Display angle labels
        }
    }
    popMatrix();
}

void parseSerialData() {
    String[] tokens = serialData.split(",");
    if (tokens.length >= 2) {
        scanAngle = float(tokens[0]);   // Parse the scan angle
        scanDistance = float(tokens[1]);// Parse the scan distance
    }
}

void drawDetection() {
    float angle = radians(scanAngle);
    float distance = scanDistance;
    float x = distance * 20; // Scale distance for display
    float fullX = radarRadius * cos(angle);
    float fullY = radarRadius * sin(angle);

    pushMatrix();
    translate(width / 2, height - 200);
    strokeWeight(4);

    // Fade effect
    noStroke();
    fill(0, 20);  // Semi-transparent black overlay
    rect(-radarRadius, -radarRadius, radarRadius * 2, radarRadius);

    // Detection line
    if (distance > 0 && distance <= maxDistance) {
        stroke(0, 0, 255);  // Blue for detected area
        line(0, 0, x * cos(angle), -x * sin(angle));
        stroke(255, 165, 0);  // Orange for the remaining area
        line(x * cos(angle), -x * sin(angle), fullX, -fullY);
    } else {
        stroke(0, 0, 255);  // Blue if no detection
        line(0, 0, fullX, -fullY);
    }
    popMatrix();
    serialData = ""; // Clear data after drawing
}

void displayInfo(float distance, float angle) {
    fill(0); // Black background for text area
    noStroke();
    rect(10, 10, 260, 80); // Area for text

    fill(255);
    textSize(20);
    text("Angle: " + nf(angle, 1, 2) + "°", 30, 30); // Display angle information
    text("Distance: " + nf(distance, 1, 2) + " cm", 30, 60); // Display distance information
}

void serialEvent(Serial p) {
    serialData = p.readStringUntil('.'); // Read serial data until '.' character
    serialData = serialData.substring(0, serialData.length() - 1); // Remove the '.' character
}