/**
 * A demo of insertion sort.
 * @author Sean Barker
 */
public class InsertionSort {

    public static void insertionSort(int[] data) {
        for (int numSorted = 1; numSorted < data.length; numSorted++) {
            // take the first unsorted value
            int toInsert = data[numSorted];

            // find where it goes among the sorted
            int checkIndex = numSorted - 1;
            while (checkIndex >= 0 && toInsert < data[checkIndex]) {
                // make room for the new value
                data[checkIndex + 1] = data[checkIndex];
                checkIndex--;
            }

            // reinsert value
            data[checkIndex + 1] = toInsert;
        }
    }

    public static void main(String[] args) {
        insertionSortDemo(10, 100);
    }

    /**
     * Runs a demo of insertion sort (same algorithm as above, but uses the SortSim
     * class to display the steps of the sort).
     */
    public static void insertionSortDemo(int dataSize, int maxVal) {
        SortSim s = new SortSim(dataSize, maxVal);
        int[] data = s.getData();

        s.update(false, -1, -1, "starting insertion sort");
        for (int numSorted = 1; numSorted < data.length; numSorted++) {
            // take the first unsorted value
            int toInsert = data[numSorted];
            s.update(false, numSorted, -1, "next value to insert is " + data[numSorted]);
            data[numSorted] = -1;

            // find where it goes among the sorted
            int checkIndex = numSorted - 1;
            s.update(false, numSorted, checkIndex + 1, "looking for insertion point for " + toInsert);
            while (checkIndex >= 0 && toInsert < data[checkIndex]) {
                // make room for the new value
                data[checkIndex + 1] = data[checkIndex];
                data[checkIndex] = -1;
                s.update(false, checkIndex, -1, "looking for insertion point for " + toInsert);
                checkIndex--;
            }

            // reinsert value
            data[checkIndex + 1] = toInsert;
            s.update(true, -1, checkIndex + 1, "reinserted value " + toInsert);
        }
        s.finish();
    }
}