MalaiseWorm.cs

using Terraria;
using Terraria.ModLoader;
using Terraria.ID;
using static Terraria.ModLoader.ModContent;
using Microsoft.Xna.Framework;
using System;
using System.Diagnostics;
using Microsoft.Xna.Framework.Graphics;
using System.IO;

namespace Malaise.NPCs.Bosses
{

    [AutoloadBossHead]
    public class MalaiseSoul : ModNPC
    {
        private int ai;
        private int attackTimer = 0;
        private bool fastSpeed = false;

        private bool stunned;
        private int stunnedTimer;

        private int frame = 1;
        private double counting;

        private const int Sphere = 50;
        private bool Phase2;

        public override void SetStaticDefaults()
        {
            DisplayName.SetDefault("Malaise Soul");
            Main.npcFrameCount[npc.type] = 4;
        }

        public override void SetDefaults()
        {
            npc.width = 64;
            npc.height = 64;

            npc.boss = true;
            npc.aiStyle = -1;
            npc.npcSlots = 5f;

            npc.lifeMax =  8500;
            npc.damage = 15;
            npc.defense = 4;
            npc.knockBackResist = 0f;

            npc.value = Item.buyPrice(gold: 10);

            npc.lavaImmune = true;
            npc.noTileCollide = true;
            npc.noGravity = true;

            npc.HitSound = SoundID.NPCHit1;
            npc.DeathSound = SoundID.NPCDeath1;
            music = MusicID.Boss2;

            bossBag = ItemType<Items.BossBags.Unconfigured.MalaiseSoulBag>();
        }

        public override void ScaleExpertStats(int numPlayers, float bossLifeScale)
        {
            npc.lifeMax = (int)(npc.lifeMax * bossLifeScale);
            npc.damage = (int)(npc.damage * 1.3f);
        }

        public override void AI()
        {
            npc.TargetClosest(true);
            Player player = Main.player[npc.target];
            Vector2 target = npc.HasPlayerTarget ? player.Center : Main.npc[npc.target].Center;
            npc.rotation = 0.0f;
            npc.netAlways = true;
            npc.TargetClosest(true);
            if(npc.life <= 4000)
            {
                npc.defense = 100;
                npc.damage = 100000;
            }
            if (npc.target < 0 || npc.target == 255 || player.dead || !player.active)
            {
                npc.TargetClosest(false);
                npc.direction = 1;
                npc.velocity.Y = npc.velocity.Y - 0.1f;
                if(npc.timeLeft > 20)
                {
                    npc.timeLeft = 20;
                    return;
                }
            }
            if(stunned)
            {
                npc.velocity.X = 0.0f;
                npc.velocity.Y = 0.0f;
                stunnedTimer++;
                if(stunnedTimer >= 100)
                {
                    stunned = false;
                    stunnedTimer = 0;
                }
            }

            ai++;
            npc.ai[0] = (float)ai * 1f;
            int distance = (int)Vector2.Distance(target, npc.Center);
            if((double)npc.ai[0] < 300)
            {
                frame = 0;
                MoveTowards(npc, target, (float)(distance > 300 ? 13f : 7f), 30f);
                npc.netUpdate = true;
            }
            else if ((double)npc.ai[0] >= 300 && (double)npc.ai[0] < 450.0)
            {
                stunned = true;
                frame = 0;
                npc.defense = 15;
                npc.damage = 15;
                MoveTowards(npc, target, (float)(distance > 300 ? 13f : 7f), 30f);
                if(npc.life <= 4000)
                {
                    npc.defense = 100;        // to be configured
                    npc.damage = 100000;      // to be configured
                }
                npc.netUpdate = true;
            }
            else if((double)npc.ai[0] >= 450.0)
            {
                frame = 0;
                stunned = false;
                npc.damage = (int)(15 * 1.3f);
                npc.defense = 5;
                if(npc.life <= 4000)
                {
                    npc.defense = 1000;    // to be configured
                    npc.damage = 1000000;  // to be configured
                }
                if(!fastSpeed)
                {
                    fastSpeed = true;
                }
                else
                {
                    if((double)npc.ai[0] % 50 == 0)
                    {
                        float speed = 12f;
                        Vector2 vector = new Vector2(npc.position.X + (float)npc.width * 0.5f, npc.position.Y + (float)npc.height * 0.5f);
                        float x = player.position.X + (float)(player.width / 2) - vector.X;
                        float y = player.position.Y + (float)(player.height / 2) - vector.Y;
                        float distance2 = (float)Math.Sqrt(x * x + y + y);
                        float factor = speed / distance2;
                        npc.velocity.X = x * factor;
                        npc.velocity.Y = y * factor;
                    }
                }
                npc.netUpdate = true;
            }

            if((double)npc.ai[0] % (Main.expertMode ? 100 : 150) == 0 && !stunned && !fastSpeed)
            {
                attackTimer++;
                if(attackTimer <= 2)
                {
                    frame = 0;
                    npc.velocity.X = 0f;
                    npc.velocity.Y = 0f;
                    Vector2 shootPos = npc.Center;
                    float accuracy = 5f * (npc.life / npc.lifeMax);
                    Vector2 shootVel = target - shootPos + new Vector2(Main.rand.NextFloat(-accuracy, accuracy), Main.rand.NextFloat(-accuracy, accuracy));
                    shootVel.Normalize();
                    shootVel *= 7.5f;
                    for(int i = 0; i < (Main.expertMode ? 5 : 3); i++)
                    {
                        Projectile.NewProjectile(shootPos.X + (float)(-100 * npc.direction) + (float)Main.rand.Next(-40, 41), shootPos.Y - (float)Main.rand.Next(-50, 40), shootVel.X, shootVel.Y, ProjectileType<Projectiles.BossProjectiles.MalaiseSoulProjectile>(), npc.damage / 3, 5f);
                    }
                }
                else
                {
                    attackTimer = 0;
                }
            }

            if((double)npc.ai[0] >= 650.0)
            {
                ai = 0;
                npc.alpha = 0;
                fastSpeed = false;
            }
        }

        public override void FindFrame(int frameHeight)
        {
            if(frame == 0)
            {
                counting += 1.0;
                if(counting < 8.0)
                {
                    npc.frame.Y = 0;
                }
                else if(counting < 24.0)
                {
                    npc.frame.Y = frameHeight;
                }
                else if(counting < 24.0)
                {
                    npc.frame.Y = frameHeight * 2;
                }
                else if(counting <32.0)
                {
                    npc.frame.Y = frameHeight * 3;
                }
                else
                {
                    counting = 0.0;
                }
            }
            else if(frame == 1)
            {
                npc.frame.Y = frameHeight * 4;
            }
            else
            {
                npc.frame.Y = frameHeight * 5;
            }
        }

        private void MoveTowards(NPC npc, Vector2 playerTarget, float speed, float turnResistance)
        {
            var move = playerTarget - npc.Center;
            float length = move.Length();
            if(length > speed)
            {
                move *= speed / length;
            }
            move = (npc.velocity * turnResistance + move) / (turnResistance + 1f);
            length = move.Length();
            if(length > speed)
            {
                move *= speed / length;
            }
            npc.velocity = move;
        }

        public override void NPCLoot()
        {
            MalaiseWorld.downedMalaiseSoul = true;
            if(Main.expertMode)
            {
                npc.DropBossBags();
            }
            else
            {
                Item.NewItem((int)npc.position.X, (int)npc.position.Y, npc.width, npc.height, ItemID.LifeCrystal, Main.rand.Next(1, 3));
                Item.NewItem((int)npc.position.X, (int)npc.position.Y, npc.width, npc.height, ItemType<Items.Drops.Malaiseite>(), Main.rand.Next(1, 3));
                if(Main.rand.Next(7) == 0)
                {
                    Item.NewItem((int)npc.position.X, (int)npc.position.Y, npc.width, npc.height, ItemType<Items.BossSummons.Unconfigured.MalaiseSoulSummon>());
                }
            }
        }

        public override void BossLoot(ref string name, ref int potionType)
        {
            potionType = ItemID.HealingPotion;
        }

        public override bool PreDraw(SpriteBatch spriteBatch, Color drawColor)
        {
            if (npc.life <= 4000)
            {
                spriteBatch.Draw(mod.GetTexture("NPCs/Bosses/Malaise1"), npc.Center - Main.screenPosition, null, Color.White * (70f / 255f), 0f, new Vector2(Sphere, Sphere), 3f, SpriteEffects.None, 0f);
            }
            return true;
        }
    }
}