// coding: UTF-8

import GUI;
import Math;
import tool.Graph2D;   // 2D graph control

// ---- Graph settings ----
const int N = 400;              // number of points
const double X_MIN = -5.0;
const double X_MAX =  5.0;
const double Y_MIN = -10.0;
const double Y_MAX =  10.0;

// Coefficients (initial values)
double a = 1.0;
double b = 0.0;
double c = 0.0;

// ---- Global handles ----
int graph;                      // 2D graph ID
double xData[ N ];
double yData[ N ];

int window;                     // GUI window
int sliderA, sliderB, sliderC;  // slider IDs
int infoLabel;                  // label for showing parameters

// ---- Compute & plot ----
void plotCubic() {
    // place x at equal intervals, compute y = a x^3 + b x^2 + c x
    double dx = (X_MAX - X_MIN) / (N - 1);
    for (int i=0; i<N; i++) {
        double x = X_MIN + dx * i;
        xData[i] = x;
        yData[i] = a*x*x*x + b*x*x + c*x;
    }
    // send data to the graph
    setGraph2DData(graph, xData, yData);
}

// ---- Update the info label ----
void updateInfo() {
    string text = 
        "f(x) = " 
        + round(a, 3, HALF_UP) + " x^3  +  "
        + round(b, 3, HALF_UP) + " x^2  +  "
        + round(c, 3, HALF_UP) + " x";
    setComponentString(infoLabel, text);
    paintComponent(infoLabel);
    paintComponent(window);
}

// ---- Initialization (top-level code runs once on startup) ----

// Launch and configure the 2D graph
graph = newGraph2D( 0, 0, 800, 500, "Cubic Plot" );
setGraph2DAutoRange( graph, false, false );
setGraph2DRange( graph, X_MIN, X_MAX, Y_MIN, Y_MAX );
setGraph2DOption( graph, "WITH_POINTS", false );
setGraph2DOption( graph, "WITH_LINES",  true );
plotCubic();

// Create the GUI window
window = newWindow( 820, 20, 420, 220, "Coefficients a, b, c" );

// Title and current values
int titleLabel = newTextLabel( 10, 10, 380, 18, "Adjust a, b, c with sliders" );
mountComponent( titleLabel, window );

infoLabel = newTextLabel( 10, 35, 380, 18, "" );
mountComponent( infoLabel, window );
updateInfo();

// Slider for a
int labelA = newTextLabel( 10, 65, 30, 18, "a" );
mountComponent( labelA, window );
sliderA = newHorizontalSlider( 40, 65, 350, 20, a, -5.0, 5.0 );
mountComponent( sliderA, window );

// Slider for b
int labelB = newTextLabel( 10, 100, 30, 18, "b" );
mountComponent( labelB, window );
sliderB = newHorizontalSlider( 40, 100, 350, 20, b, -5.0, 5.0 );
mountComponent( sliderB, window );

// Slider for c
int labelC = newTextLabel( 10, 135, 30, 18, "c" );
mountComponent( labelC, window );
sliderC = newHorizontalSlider( 40, 135, 350, 20, c, -5.0, 5.0 );
mountComponent( sliderC, window );

// Redraw the window at the end
paintComponent( window );

// ---- Event handler ----
void onSliderMove(int id, float value) {
    if (id == sliderA) { a = value; }
    if (id == sliderB) { b = value; }
    if (id == sliderC) { c = value; }
    updateInfo();
    plotCubic();
}