engine/gavania-core/src/game/content/objects/npc.rs

use std::{
    collections::{hash_map::Iter, HashMap},
    path::Path,
};

use crate::game::content::prelude::*;
use crate::{game::game::GameHandle, Rarities};

use anyhow::Result;
use assetpath::AssetPath;
use cgmath::{vec3, Deg, InnerSpace, Vector3, Zero};
use engine::prelude::*;

const NPC_BASE_STATS: u32 = 2;

create_settings_section!(
    NPCMetaInfo,
    "Meta",
    {
        entity_file: String,
        name: String,
        movement_speed: f32,
        aggro_radius: f32,
        deaggro_radius: f32,
        scale: f32,

        mob_type: NPCType,

        strength_per_level: f32,
        intelligence_per_level: f32,
        agility_per_level: f32,
    }
);

create_settings_section!(
    AbilitySlot0,
    "AbilitySlot_0",
    {
        used: bool,
        name: String,
        rarity: Rarities,
        level: f32,
        [addons: String],
    }
);

create_settings_section!(
    AbilitySlot1,
    "AbilitySlot_1",
    {
        used: bool,
        name: String,
        rarity: Rarities,
        level: f32,
        [addons: String],
    }
);

create_settings_section!(
    AbilitySlot2,
    "AbilitySlot_2",
    {
        used: bool,
        name: String,
        rarity: Rarities,
        level: f32,
        [addons: String],
    }
);

create_settings_section!(
    AbilitySlot3,
    "AbilitySlot_3",
    {
        used: bool,
        name: String,
        rarity: Rarities,
        level: f32,
        [addons: String],
    }
);

pub trait NPCAbilitySlot {
    fn used(&mut self) -> &mut bool;
    fn name(&mut self) -> &mut String;
    fn rarity(&mut self) -> &mut Rarities;
    fn level(&mut self) -> &mut f32;
    fn addons(&mut self) -> &mut [String];
}

impl NPCAbilitySlot for AbilitySlot0 {
    fn used(&mut self) -> &mut bool {
        &mut self.used
    }

    fn name(&mut self) -> &mut String {
        &mut self.name
    }

    fn rarity(&mut self) -> &mut Rarities {
        &mut self.rarity
    }

    fn level(&mut self) -> &mut f32 {
        &mut self.level
    }

    fn addons(&mut self) -> &mut [String] {
        &mut self.addons
    }
}

impl NPCAbilitySlot for AbilitySlot1 {
    fn used(&mut self) -> &mut bool {
        &mut self.used
    }

    fn name(&mut self) -> &mut String {
        &mut self.name
    }

    fn rarity(&mut self) -> &mut Rarities {
        &mut self.rarity
    }

    fn level(&mut self) -> &mut f32 {
        &mut self.level
    }

    fn addons(&mut self) -> &mut [String] {
        &mut self.addons
    }
}

impl NPCAbilitySlot for AbilitySlot2 {
    fn used(&mut self) -> &mut bool {
        &mut self.used
    }

    fn name(&mut self) -> &mut String {
        &mut self.name
    }

    fn rarity(&mut self) -> &mut Rarities {
        &mut self.rarity
    }

    fn level(&mut self) -> &mut f32 {
        &mut self.level
    }

    fn addons(&mut self) -> &mut [String] {
        &mut self.addons
    }
}

impl NPCAbilitySlot for AbilitySlot3 {
    fn used(&mut self) -> &mut bool {
        &mut self.used
    }

    fn name(&mut self) -> &mut String {
        &mut self.name
    }

    fn rarity(&mut self) -> &mut Rarities {
        &mut self.rarity
    }

    fn level(&mut self) -> &mut f32 {
        &mut self.level
    }

    fn addons(&mut self) -> &mut [String] {
        &mut self.addons
    }
}

create_settings_container!(
    NPCSettings,
    {
        meta: NPCMetaInfo,

        ability_0: AbilitySlot0,
        ability_1: AbilitySlot1,
        ability_2: AbilitySlot2,
        ability_3: AbilitySlot3,
    }
);

pub struct NPCFactory {
    elite_npcs: HashMap<String, NPCSettings>,
    normal_npcs: HashMap<String, NPCSettings>,
    boss_npcs: HashMap<String, NPCSettings>,
}

impl NPCFactory {
    pub fn new(npc_directory: AssetPath) -> Result<Self> {
        let files = search_dir_recursively(&npc_directory.full_path(), ".npc")?;

        let mut elite_npcs = HashMap::new();
        let mut normal_npcs = HashMap::new();
        let mut boss_npcs = HashMap::new();

        for npc_file in files {
            let npc_name = Path::new(&npc_file.full_path())
                .file_stem()
                .unwrap()
                .to_str()
                .unwrap()
                .to_string();

            let npc_setting = NPCSettings::load(npc_file)?;

            match npc_setting.meta.mob_type {
                NPCType::Normal => normal_npcs.insert(npc_name, npc_setting),
                NPCType::Elite => elite_npcs.insert(npc_name, npc_setting),
                NPCType::Boss => boss_npcs.insert(npc_name, npc_setting),
            };
        }

        Ok(Self {
            elite_npcs,
            normal_npcs,
            boss_npcs,
        })
    }

    pub fn npc(&self, name: &String, npc_type: impl Into<NPCType>) -> Option<&NPCSettings> {
        match npc_type.into() {
            NPCType::Normal => self.normal_npcs.get(name),
            NPCType::Elite => self.elite_npcs.get(name),
            NPCType::Boss => self.boss_npcs.get(name),
        }
    }

    pub fn npcs(&self, npc_type: impl Into<NPCType>) -> Iter<'_, String, NPCSettings> {
        match npc_type.into() {
            NPCType::Normal => self.normal_npcs.iter(),
            NPCType::Elite => self.elite_npcs.iter(),
            NPCType::Boss => self.boss_npcs.iter(),
        }
    }

    fn find_setting(&self, npc: &String) -> Result<&NPCSettings> {
        self.normal_npcs
            .get(npc)
            .or(self.elite_npcs.get(npc))
            .or(self.boss_npcs.get(npc))
            .ok_or(anyhow::Error::msg(format!("NPC file not found {}", npc)))
    }

    pub fn create_npc(
        &self,
        entity_manager: &mut EntityManager,
        game_handle: &GameHandle,
        npc: &String,
        level: u32,
        position: Vector3<f32>,
    ) -> Result<EntityObject> {
        let game = game_handle.upgrade();
        let npc_settings = self.find_setting(npc)?;

        let mut entity_object =
            entity_manager.load_entity(game.engine().assets(), &npc_settings.meta.entity_file)?;

        // ========== create components ==========

        // location
        let location = Location::new_and_setup(&mut entity_object)?;
        location.update_raw(position, Deg(Random::range_f32(0.0, 360.0)));

        // scale
        let scale = npc_settings.meta.scale;
        location.set_scale(vec3(scale, scale, scale));

        let hitbox = entity_object.get_component_mut::<HitBox>()?;
        hitbox.set_radius(hitbox.radius() * scale);
        hitbox.set_height(hitbox.height() * scale);

        // movement
        let movement = Movement::new(
            npc_settings.meta.movement_speed,
            entity_object.get_component_mut::<Audio>().ok(),
        );

        // attributes
        let strength = (level as f32 * npc_settings.meta.strength_per_level) as u32;
        let intelligence = (level as f32 * npc_settings.meta.intelligence_per_level) as u32;
        let agility = (level as f32 * npc_settings.meta.agility_per_level) as u32;

        let mut attributes = Attributes::load(
            NPC_BASE_STATS + strength,
            NPC_BASE_STATS + agility,
            NPC_BASE_STATS + intelligence,
        );

        // statistics
        let mut stats = Statistics::default();
        stats.update(&mut attributes, &game.attribute_settings, None);

        // character status
        let character_status = CharacterStatus::new_full(&stats);

        // name
        let npc_name = NPCName::new(npc);

        // entity faction
        entity_object.insert_component(FactionNPC);

        // npc type
        match npc_settings.meta.mob_type {
            NPCType::Normal => {
                entity_object.insert_component(NPCNormal);
            }
            NPCType::Elite => {
                entity_object.insert_component(NPCElite);
            }
            NPCType::Boss => {
                entity_object.insert_component(NPCBoss);
            }
        }

        // health bar
        match npc_settings.meta.mob_type {
            NPCType::Boss => {
                let name = npc_name.name.clone();
                entity_object.insert_component(BossHealthBar::new(&game, name)?);
            }

            _ => (),
        }

        // level
        let level = Level::load(level, 0, &game.experience_settings);

        // ai

        let ai = SimpleAI::new(6.0, 9.0, entity_object.as_entity());

        // abilities
        let abilities =
            AbilitySlots::load_for_npc(level.level(), npc_settings, game_handle.clone())?;

        // ========== insert components ==========
        entity_object.insert_component(movement);
        entity_object.insert_component(attributes);
        entity_object.insert_component(stats);
        entity_object.insert_component(character_status);
        entity_object.insert_component(level);
        entity_object.insert_component(abilities);
        entity_object.insert_component(npc_name);

        entity_object.insert_component(ai);

        // set hit box event
        entity_object
            .get_component_mut::<HitBox>()
            .unwrap()
            .set_event(move |scene, me, collider| {
                let mut entity_multi_mut = scene.entities_multi_mut();

                if let Ok(my_object) = entity_multi_mut.get(me) {
                    if let Ok(collider_object) = entity_multi_mut.get(collider) {
                        if collider_object.get_component::<FactionNPC>().is_ok() {
                            // if we hit an allied NPC, move both in parallel
                            let my_movement = my_object.get_component_mut::<Movement>().unwrap();
                            let other_movement =
                                collider_object.get_component_mut::<Movement>().unwrap();

                            if my_movement.direction().is_zero()
                                || other_movement.direction().is_zero()
                            {
                                return Ok(CollisionEventType::Block);
                            }

                            let common_dir =
                                (my_movement.direction() + other_movement.direction()).normalize();

                            my_movement.set_direction(common_dir);
                            other_movement.set_direction(common_dir);

                            return Ok(CollisionEventType::Ignore);
                        } else if collider_object.get_component::<FactionFriendly>().is_ok() {
                            // friendly NPCs are ignored
                            return Ok(CollisionEventType::Ignore);
                        }
                    }
                }

                Ok(CollisionEventType::Block)
            });

        Ok(entity_object)
    }
}