#include "TileList.h"

TileList::TileList()
{
    tiles = new Tile[10];
    cur_size = 10;
}

TileList::~TileList()
{
    delete tiles;
}

void TileList::addTile(Tile tile)
{
    if (amount_tiles == cur_size) {
        Tile *expanded_tiles = new Tile[cur_size + 10];
        for (int i = 0; i < cur_size; i++) {
            expanded_tiles[i] = tiles[i];
        }
        cur_size += 10;
        delete tiles;
        tiles = expanded_tiles;
    }
    tiles[amount_tiles++] = tile;
}

void TileList::drawAll(QGraphicsScene* scene) const
{
    for (int i = 0; i < amount_tiles; i++) {
        (tiles + i)->draw(scene);
    }
}

int TileList::indexOfTopTile(int x, int y) const
{
    for (int i = 0; i < amount_tiles; i++) {
        if ((tiles + i)->contains(x, y)) {
            return i;
        }
    }
    return -1;
}

int TileList::indexOfBottomTile(int x, int y) const
{
    int index = -1;
    for (int i = 0; i < amount_tiles; i++) {
        if ((tiles + i)->contains(x, y)) {
            index = i;
        }
    }
    return index;
}

void TileList::shiftRight(int start, int end)
{
    // start is the free value, end is the lost value
    // e.g. when length=5, start=1, end=4:
    // 0 1 2 3 4 5
    // 0 1 1 2 3 5
    for (int i = end; i > start; i--) {
        tiles[i] = tiles[i - 1];
    }
}

void TileList::shiftLeft(int start, int end)
{
    // start is the free value, end is the lost value
    // e.g. when length=5, start=4, end=1:
    // 0 1 2 3 4 5
    // 0 2 3 4 4 5
    for (int i = start; i < end; i++) {
        tiles[i] = tiles[i + 1];
    }
}

void TileList::raise(int x, int y)
{
    // 0 1 2 3 4 5  -
    // 0 1 2 3 4 5  3
    // 0 1 2 4 5 5  3
    // 0 1 2 4 5 3  -
    int index = indexOfTopTile(x, y);
    if (index == -1 || index == amount_tiles - 1) {
        return;
    }
    Tile tmpTile = tiles[index];
    shiftLeft(index, amount_tiles - 1);
    tiles[amount_tiles - 1] = tmpTile;
}

void TileList::lower(int x, int y)
{
    //  0 1 2 3 4 5  -
    //  0 1 2 3 4 5  3
    //  0 0 1 2 4 5  3
    //  3 0 1 2 4 5  -
    int index = indexOfBottomTile(x, y);
    if (index == -1 || index == 0) {
        return;
    }
    Tile tmpTile = tiles[index];
    shiftRight(0, index);
    tiles[0] = tmpTile;
}

void TileList::remove(int x, int y)
{
    int index = indexOfBottomTile(x, y);
    if (index != -1) {
        shiftLeft(index, amount_tiles - 1);
        amount_tiles--;
    }
}

void TileList::removeAll(int x, int y)
{
    int index = indexOfTopTile(x, y);
    while (index != -1) {
        shiftLeft(index, amount_tiles - 1);
        amount_tiles--;
        index = indexOfTopTile(x, y);
    }
}