package com.gildedrose;

import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertEquals;

class GildedRoseTest {
    private static final int SULFURAS_QUALITY = 80;
    @Test
    public void agedBrieIncreasesInQualityByOneEachDay() {
        Item[] items = new Item[] { new Item(GildedRose.AGED_BRIE, 2, 0) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 1);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 2);
    }

    @Test
    public void sulfurasSellInDateNeverChanges() {
        int sellIn = 10;
        Item[] items = new Item[] { new Item(GildedRose.SULFURAS, sellIn, SULFURAS_QUALITY) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, sellIn);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, sellIn);
    }

    @Test
    public void sulfurasValueNeverChanges() {
        Item[] items = new Item[] { new Item(GildedRose.SULFURAS, 10, SULFURAS_QUALITY) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, SULFURAS_QUALITY);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, SULFURAS_QUALITY);
    }

    @Test
    public void sulfurasValueIsAlways80() {
        Item[] items = new Item[] { new Item(GildedRose.SULFURAS, 10, SULFURAS_QUALITY) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, SULFURAS_QUALITY);
    }

    @Test
    public void backstagePassesQualityIncreasesByTwoWhenThereAreTenDaysOrLessBeforeTheConcert() {
        int quality = 0;
        Item[] items = new Item[] { new Item(GildedRose.BACKSTAGE_PASSES, 10, quality) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 2);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 4);
    }

    @Test
    public void backstagePassesQualityIncreasesByThreeWhenThereAreFiveDaysOrLessBeforeTheConcert() {
        int quality = 0;
        Item[] items = new Item[] { new Item(GildedRose.BACKSTAGE_PASSES, 5, quality) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 3);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 6);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 9);
    }

    @Test
    public void backstagePassesQualityDropsToZeroAfterTheConcert() {
        int quality = 10;
        Item[] items = new Item[] { new Item(GildedRose.BACKSTAGE_PASSES, 1, quality) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 13);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 0);
    }

    @Test
    public void qualityIsNeverNegative() {
        // todo: should add a similar case for conjured
        int quality = 1;
        Item[] items = new Item[] { new Item("generic item", 5, quality) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 0);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 0);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 0);
    }

    @Test
    public void qualityIsNeverOverFiftyForAgedBrie() {
        Item[] items = new Item[] { new Item(GildedRose.AGED_BRIE, 5, 50) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 50);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 50);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 50);
    }

    @Test
    public void qualityIsNeverOverFiftyForBackstagePasses() {
        Item[] items = new Item[] { new Item(GildedRose.BACKSTAGE_PASSES, 5, 50) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 50);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 50);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 50);
    }

    @Test
    public void qualityDecreasesByOneEachDayForGenericItems() {
        Item[] items = new Item[] { new Item("generic item", 5, 5) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 4);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 3);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 2);
    }

    @Test
    public void qualityDecreasesByTwoEachDayForGenericItemsAfterSellInDate() {
        Item[] items = new Item[] { new Item("generic item", 1, 6) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 5);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 3);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 1);
    }

    @Test
    public void sellInDateDecreasesByOneEachDayForAgedBrie() {
        Item[] items = new Item[] { new Item(GildedRose.AGED_BRIE, 5, 1) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, 4);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, 3);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, 2);
    }

    @Test
    public void sellInDateDecreasesByOneEachDayForBackstagePasses() {
        Item[] items = new Item[] { new Item(GildedRose.BACKSTAGE_PASSES, 5, 1) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, 4);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, 3);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, 2);
    }

    @Test
    public void sellInDateDecreasesByOneEachDayForGenericItems() {
        Item[] items = new Item[] { new Item("generic item", 5, 1) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, 4);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, 3);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, 2);
    }

    @Test
    public void sellInDateCanBeNegativeForGenericItems() {
        Item[] items = new Item[] { new Item("generic item", 1, 1) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, 0);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, -1);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, -2);
    }

    @Test
    public void sellInDateCanBeNegativeForAgedBrie() {
        Item[] items = new Item[] { new Item(GildedRose.AGED_BRIE, 1, 1) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, 0);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, -1);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, -2);
    }

    @Test
    public void sellInDateCanBeNegativeForBackStagePasses() {
        Item[] items = new Item[] { new Item(GildedRose.BACKSTAGE_PASSES, 1, 1) };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, 0);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, -1);
        app.updateQuality();
        assertEquals(app.items.get(0).sellIn, -2);
    }

    @Test
    public void itUpdatesAllItemsPassedIn() {
        Item[] items = new Item[] {
            new Item("generic item 1", 5, 5),
            new Item("generic item 2", 5, 10)
        };
        GildedRose app = new GildedRose(items);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 4);
        assertEquals(app.items.get(1).quality, 9);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 3);
        assertEquals(app.items.get(1).quality, 8);
        app.updateQuality();
        assertEquals(app.items.get(0).quality, 2);
        assertEquals(app.items.get(1).quality, 7);
    }
}