// 2D vector class to make some of the math easier
class Vec2D {
    constructor(x, y) {
        this.x = x;
        this.y = y;
    }

    magnitude() {
        return Math.sqrt(this.x * this.x + this.y * this.y);
    }

    angle() {
        return Math.atan2(this.y, this.x);
    }
}

// Swerve module class to represent a single wheel
class SwerveModule {
    constructor(x, y, name) {
        this.position = new Vec2D(x, y);
        this.velocity = new Vec2D(0, 0);
        this.angle = 0;
        this.speed = 0;
        this.name = name;
    }

    calculateState(velocityX, velocityY, turnSpeed) {
        // Take the requested speed and turn rate of the robot and calculate
        // speed and angle of this module to achieve it

        // Calculate rotation contribution (perpendicular to position vector)
        const rotX = -this.position.y * omega;
        const rotY = this.position.x * omega;

        // Combine translation and rotation
        this.velocity.x = velocityX + rotX;
        this.velocity.y = velocityY + rotY;

        // Calculate speed and angle
        this.speed = this.velocity.magnitude();
        this.angle = this.velocity.angle();
    }
}

// Swerve drive class to represent the robot as a whole
class SwerveDrive {
    constructor(modulePositionsAndNames) {
        // Take an array of module positions with a name and create an array of SwerveModule objects
        this.modules = modulePositionsAndNames.map(module =>
            new SwerveModule(module.x, module.y, module.name)
        );
    }

    drive(velocityX, velocityY, turnSpeed, maxSpeed) {
        // Take in a requested speeds and update every module
        this.modules.forEach(module =>
            module.calculateState(velocityX, velocityY, turnSpeed)
        );

        // If any speeds exceed the max speed, normalize down so we don't effect movement direction
        const maxCalculated = Math.max(...this.modules.map(m => m.speed), 0);
        if (maxCalculated > maxSpeed) {
            const scale = maxSpeed / maxCalculated;
            this.modules.forEach(module => {
                module.speed *= scale;
            });
        }
    }
}

// Get all control elements
const vxSlider = document.getElementById('vx-slider');
const vySlider = document.getElementById('vy-slider');
const omegaSlider = document.getElementById('omega-slider');
const maxSpeedSlider = document.getElementById('max-speed-slider');
const moduleCountInput = document.getElementById('module-count');

// Get all output elements
const vxOutput = document.getElementById('vx-value');
const vyOutput = document.getElementById('vy-value');
const omegaOutput = document.getElementById('omega-value');
const maxSpeedOutput = document.getElementById('max-speed-value');

// Get button elements
const resetBtn = document.getElementById('reset-btn');
const generateInputsBtn = document.getElementById('generate-inputs-btn');
const applyCustomBtn = document.getElementById('apply-custom-btn');

// Preset buttons
const preset2WheelBtn = document.getElementById('preset-2wheel');
const preset3WheelBtn = document.getElementById('preset-3wheel');
const preset4WheelBtn = document.getElementById('preset-4wheel');
const preset4RectBtn = document.getElementById('preset-4rect');
const preset6WheelBtn = document.getElementById('preset-6wheel');
const preset8WheelBtn = document.getElementById('preset-8wheel');

// Add event listeners for drive controls
vxSlider.addEventListener('input', (e) => {
    vxOutput.textContent = parseFloat(e.target.value).toFixed(1);
});

vySlider.addEventListener('input', (e) => {
    vyOutput.textContent = parseFloat(e.target.value).toFixed(1);
});

omegaSlider.addEventListener('input', (e) => {
    omegaOutput.textContent = parseFloat(e.target.value).toFixed(1);
});

maxSpeedSlider.addEventListener('input', (e) => {
    maxSpeedOutput.textContent = parseFloat(e.target.value).toFixed(1);
});