package com.ncu.list;

/**
 * 
 * 順序結構線性列表
 * 
 * 
 */
public class SquenceList<T> {
    private int size; // 線性表的長度
    private Object[] listArray;
    private int currenSize = 0; // 當前線性表中的數據

    public SquenceList() {

    }

    public SquenceList(int size) {
        this.size = size;
        listArray = new Object[size];
    }

    public void arrayCopy(int index) {
        Object newArray[] = new Object[size];
        for (int i = 0; i < currenSize; i++) {
            if (i >= index) {
                newArray[i] = listArray[i + 1];
            } else {
                newArray[i] = listArray[i];
            }
        }
        listArray = newArray;
        newArray = null; // 釋放資源
    }

    /**
     * 根據索引位置移除元素
     * 
     * @param index
     */
    public void remove(int index) {
        index = index - 1;
        if (index < 0 || index > currenSize) {
            System.out.println("線性表索引越界");
        }
        if (currenSize == 0) {
            System.out.println("線性表為空");
        } else {
            currenSize--;
            arrayCopy(index);
            if (currenSize == 0) {
                listArray = null;
            }
        }
    }

    /**
     * 根據元素內容移除元素
     * 
     * @param element
     */
    public void removeLocate(T element) {
        for (int i = 0; i < currenSize;) {
            if (element.equals(listArray[i])) {
                remove(i + 1);
            } else {
                i++;
            }
        }
    }

    /**
     * 從線性表尾段插入數據
     * 
     * @param element
     */
    public void add(T element) {
        if (currenSize > size || currenSize < 0) {
            System.out.println("線性表索引越界");
        } else {
            listArray[currenSize] = element;
            currenSize++;
        }
    }

    private void insert(T element, int index) {
        index = index - 1;
        if (currenSize > size || currenSize < 0 || index < 0
                || index >= currenSize) {
            System.out.println("線性表索引越界");
        } else {
            Object newArray[] = new Object[size];
            for (int i = 0; i < currenSize; i++) {
                if (i >= index) {
                    newArray[index] = element;
                    newArray[i + 1] = listArray[i];
                } else {
                    newArray[i] = listArray[i];
                }

            }
            listArray = newArray;
            newArray = null;
            currenSize++;
        }
    }

    /**
     * 在指定索引位置插入數據
     * 
     * @param element
     * @param index
     */
    public void add(T element, int index) {
        if (index == size) {
            add(element);
        } else {
            insert(element, index);
        }
    }

    /**
     * 刪除線性表最后一個元素
     */
    public void delete() {
        if (isEmpty()) {
            System.out.println("線性表為空，不能刪除");
        } else {
            listArray[currenSize - 1] = null;
            currenSize--;
        }
    }

    /**
     * 判讀線性表是否為空
     * 
     * @return
     */
    public boolean isEmpty() {
        if (currenSize == 0) {
            return true;
        } else {
            return false;
        }
    }

    /**
     * 根據索引找到相應的元素
     * 
     * @param index
     * @return
     */
    public T get(int index) {
        T obj = null;
        if (isEmpty() || index > currenSize || index < 0) {
            System.out.println("線性表為空，不能刪除");
        } else {
            obj = (T) listArray[index - 1];
        }

        return obj;
    }

    /**
     * 清空線性表
     */
    public void clear() {
        size = 0;
        currenSize = 0;
    }

    /**
     * 得到線性表當前的元素的個數
     * 
     * @return
     */
    public int size() {
        return currenSize;
    }

    public void showList() {
        if (currenSize > 0) {
            for (int i = 0; i < currenSize; i++) {
                System.out.println(listArray[i]);

            }
        } else {
            System.out.println("線性表為空");
        }

        System.out.println("------------");
    }

    public static void main(String[] args) {
        SquenceList<Integer> list = new SquenceList<Integer>(10);
    }
}