import { ModifiableData } from "../common/common-data";
import { DS4 } from "../config";
import { DS4Item } from "../item/item";
import { DS4ItemData, ItemType } from "../item/item-data";
import { DS4ActorData } from "./actor-data";

/**
 * The Actor class for DS4
 */
export class DS4Actor extends Actor<DS4ActorData, DS4Item> {
    /** @override */
    prepareData(): void {
        this.data = duplicate(this._data) as DS4ActorData;
        if (!this.data.img) this.data.img = CONST.DEFAULT_TOKEN;
        if (!this.data.name) this.data.name = "New " + this.entity;
        this.prepareBaseData();
        this.prepareEmbeddedEntities();
        this.applyActiveEffectsToNonDerivedData();
        this.prepareDerivedData();
        this.applyActiveEffectsToDerivedData();
    }

    /** @override */
    prepareBaseData(): void {
        const data = this.data;
        const attributes = data.data.attributes;
        Object.values(attributes).forEach(
            (attribute: ModifiableData<number>) => (attribute.total = attribute.base + attribute.mod),
        );

        const traits = data.data.traits;
        Object.values(traits).forEach((trait: ModifiableData<number>) => (trait.total = trait.base + trait.mod));
    }

    applyActiveEffectsToNonDerivedData(): void {
        this.applyActiveEffectsFiltered((change) => !this.derivedDataProperties.includes(change.key));
    }

    applyActiveEffectsToDerivedData(): void {
        this.applyActiveEffectsFiltered((change) => this.derivedDataProperties.includes(change.key));
    }

    /**
     * Apply ActiveEffectChanges to the Actor data which are caused by ActiveEffects and satisfy the given predicate.
     *
     * @param predicate - The predicate that ActiveEffectChanges need to satisfy in order to be applied
     */
    applyActiveEffectsFiltered(predicate: (change: ActiveEffectChange) => boolean): void {
        const overrides: Record<string, unknown> = {};

        // Organize non-disabled effects by their application priority
        const changes = this.effects.reduce(
            (changes: Array<ActiveEffectChange & { effect: ActiveEffect<DS4Actor> }>, e) => {
                if (e.data.disabled) return changes;

                return changes.concat(
                    e.data.changes.filter(predicate).map((c) => {
                        const duplicatedChange = duplicate(c) as ActiveEffect.Change;
                        duplicatedChange.priority = duplicatedChange.priority ?? duplicatedChange.mode * 10;
                        return { ...duplicatedChange, effect: e };
                    }),
                );
            },
            [],
        );
        changes.sort((a, b) => a.priority - b.priority);

        // Apply all changes
        for (const change of changes) {
            const result = change.effect.apply(this, change);
            if (result !== null) overrides[change.key] = result;
        }

        // Expand the set of final overrides
        this.overrides = expandObject({ ...flattenObject(this.overrides ?? {}), ...overrides });
    }

    /** @override */
    prepareDerivedData(): void {
        this._prepareCombatValues();
    }

    /** The list of properties that are derived from others, given in dot notation */
    get derivedDataProperties(): Array<string> {
        return Object.keys(DS4.i18n.combatValues)
            .map((combatValue) => `data.combatValues.${combatValue}.total`)
            .concat("data.combatValues.hitPoints.max");
    }

    /**
     * The list of item types that can be owned by this actor.
     */
    get ownableItemTypes(): Array<ItemType> {
        switch (this.data.type) {
            case "character":
                return [
                    "weapon",
                    "armor",
                    "shield",
                    "trinket",
                    "equipment",
                    "spell",
                    "talent",
                    "racialAbility",
                    "language",
                    "alphabet",
                ];
            case "creature":
                return ["weapon", "armor", "shield", "trinket", "equipment", "spell", "specialCreatureAbility"];
            default:
                return [];
        }
    }

    /**
     * Checks whether or not the given item type can be owned by the actor.
     * @param itemType - The item type to check
     */
    canOwnItemType(itemType: ItemType): boolean {
        return this.ownableItemTypes.includes(itemType);
    }

    /**
     *  Prepares the combat values of the actor.
     */
    private _prepareCombatValues(): void {
        const data = this.data.data;
        const armorValueOfEquippedItems = this._calculateArmorValueOfEquippedItems();
        data.combatValues.hitPoints.base =
            (data.attributes.body.total ?? 0) + (data.traits.constitution.total ?? 0) + 10;

        data.combatValues.defense.base =
            (data.attributes.body.total ?? 0) + (data.traits.constitution.total ?? 0) + armorValueOfEquippedItems;
        data.combatValues.initiative.base = (data.attributes.mobility.total ?? 0) + (data.traits.agility.total ?? 0);
        data.combatValues.movement.base = (data.attributes.mobility.total ?? 0) / 2 + 1;
        data.combatValues.meleeAttack.base = (data.attributes.body.total ?? 0) + (data.traits.strength.total ?? 0);
        data.combatValues.rangedAttack.base =
            (data.attributes.mobility.total ?? 0) + (data.traits.dexterity.total ?? 0);
        data.combatValues.spellcasting.base =
            (data.attributes.mind.total ?? 0) + (data.traits.aura.total ?? 0) - armorValueOfEquippedItems;
        data.combatValues.targetedSpellcasting.base =
            (data.attributes.mind.total ?? 0) + (data.traits.dexterity.total ?? 0) - armorValueOfEquippedItems;

        Object.values(data.combatValues).forEach(
            (combatValue: ModifiableData<number>) => (combatValue.total = combatValue.base + combatValue.mod),
        );

        data.combatValues.hitPoints.max = data.combatValues.hitPoints.total;
    }

    /**
     * Calculates the total armor value of all equipped items.
     */
    private _calculateArmorValueOfEquippedItems(): number {
        return this.items
            .map((item) => {
                if (item.data.type === "armor" || item.data.type === "shield") {
                    return item.data.data.equipped ? item.data.data.armorValue : 0;
                } else {
                    return 0;
                }
            })
            .reduce((a, b) => a + b, 0);
    }

    /**
     * Handle how changes to a Token attribute bar are applied to the Actor.
     * This only differs from the base implementation by also allowing negative values.
     * @override
     */
    async modifyTokenAttribute(attribute: string, value: number, isDelta = false, isBar = true): Promise<this> {
        const current = getProperty(this.data.data, attribute);

        // Determine the updates to make to the actor data
        let updates: Record<string, number>;
        if (isBar) {
            if (isDelta) value = Math.min(Number(current.value) + value, current.max);
            updates = { [`data.${attribute}.value`]: value };
        } else {
            if (isDelta) value = Number(current) + value;
            updates = { [`data.${attribute}`]: value };
        }

        // Call a hook to handle token resource bar updates
        const allowed = Hooks.call("modifyTokenAttribute", { attribute, value, isDelta, isBar }, updates);
        return allowed !== false ? this.update(updates) : this;
    }

    /** @override */
    // TODO(types): Improve typing once it's fixed in upstream (arrays can be passed!)
    createEmbeddedEntity(
        embeddedName: "OwnedItem",
        data: DeepPartial<DS4ItemData>,
        options?: Record<string, unknown>,
    ): Promise<DS4ItemData>;
    createEmbeddedEntity(
        embeddedName: "ActiveEffect",
        data: DeepPartial<DS4ItemData>,
        options?: Record<string, unknown>,
    ): Promise<ActiveEffect.Data>;
    createEmbeddedEntity(
        embeddedName: "OwnedItem" | "ActiveEffect",
        data: DeepPartial<DS4ItemData> | DeepPartial<ActiveEffect.Data>,
        options?: Record<string, unknown>,
    ): Promise<DS4ItemData> | Promise<ActiveEffect.Data> {
        if (embeddedName === "OwnedItem") {
            preCreateOwnedItem.bind(this)(data);
            return super.createEmbeddedEntity(embeddedName, data, options);
        }
        return super.createEmbeddedEntity(embeddedName, data, options);
    }

    /** @override */
    // TODO(types): Improve typing once it's fixed in upstream
    updateEmbeddedEntity(embeddedName: string, data: unknown[], options?: Entity.UpdateOptions): Promise<unknown[]>;
    updateEmbeddedEntity(embeddedName: string, data: unknown, options?: Entity.UpdateOptions): Promise<unknown>;
    updateEmbeddedEntity(
        embeddedName: string,
        updateData: unknown | unknown[],
        options?: Record<string, unknown>,
    ): Promise<unknown> {
        if (embeddedName === "OwnedItem") {
            preUpdateOwnedItem.bind(this)(updateData as DeepPartial<DS4ItemData> | Array<DeepPartial<DS4ItemData>>);
        }
        return super.updateEmbeddedEntity(embeddedName, updateData, options);
    }
}

/**
 * If the item that is going to be created is equipable, set it to be non equipped and disable all ActiveEffects
 * contained in the item
 * @param itemData - The data of the item to be created
 */
function preCreateOwnedItem(itemData: DeepPartial<DS4ItemData> | DeepPartial<DS4ItemData>[]): void {
    const dataArray = itemData instanceof Array ? itemData : [itemData];
    dataArray.forEach((data) => {
        if (data.data && "equipped" in data.data) {
            data.effects = data.effects?.map((effect) => ({ ...effect, disabled: true }));
            data.data.equipped = false;
        }
    });
    console.log(itemData);
}

/**
 * If the equipped flag of one or more items changed, update all ActiveEffects originating from those items
 * accordingly.
 * @param updateData - The change that is going to be applied to the owned item(s)
 */
function preUpdateOwnedItem<T extends Actor>(
    this: T,
    updateData: DeepPartial<DS4ItemData> | Array<DeepPartial<DS4ItemData>>,
): void {
    const dataArray = updateData instanceof Array ? updateData : [updateData];
    dataArray.forEach((data) => {
        if (data.data && "equipped" in data.data) {
            const equipped = data.data.equipped;
            const origin = `Actor.${this.id}.OwnedItem.${data._id}`;
            const effects = this.effects
                .filter((e) => e.data.origin === origin)
                .map((e) => {
                    const effectData = duplicate(e.data);
                    effectData.disabled = !(equipped ?? true);
                    return effectData;
                });
            if (effects.length > 0)
                this.updateEmbeddedEntity("ActiveEffect", (effects as unknown) as Record<string, unknown>);
        }
    });
}

const oldTokenCreateEmbeddedEntity = ActorTokenHelpers.prototype.createEmbeddedEntity;
const oldTokenUpdateEmbeddedEntity = ActorTokenHelpers.prototype.updateEmbeddedEntity;

function tokenCreateEmbeddedEntity<T extends Actor, U>(
    this: T,
    embeddedName: "OwnedItem" | "ActiveEffect",
    data: Expanded<U> extends DeepPartial<ActiveEffect.Data> | DeepPartial<DS4ItemData>
        ? U | U[]
        :
              | DeepPartial<ActiveEffect.Data>
              | DeepPartial<ActiveEffect.Data>[]
              | DeepPartial<DS4ItemData>
              | DeepPartial<DS4ItemData>[],
    options?: Entity.UpdateOptions,
) {
    if (embeddedName === "OwnedItem") {
        const itemDataArray =
            data instanceof Array
                ? data.map((it) => expandObject(it) as DS4ItemData)
                : [expandObject(data as Record<string, unknown>) as DS4ItemData];
        preCreateOwnedItem.bind(this)(itemDataArray);
        // eslint-disable-next-line
        // @ts-ignore
        return oldTokenCreateEmbeddedEntity.bind(this)(embeddedName, itemDataArray, options);
    }
    // eslint-disable-next-line
    // @ts-ignore
    return oldTokenCreateEmbeddedEntity.bind(this)(embeddedName, data, options);
}

function tokenUpdateEmbeddedEntity<T extends Actor, U>(
    this: T,
    embeddedName: "OwnedItem" | "ActiveEffect",
    data: Expanded<U> extends
        | (DeepPartial<ActiveEffect.Data> & { _id: string })
        | (DeepPartial<DS4ItemData> & { _id: string })
        ? U | U[]
        :
              | (DeepPartial<ActiveEffect.Data> & { _id: string })
              | (DeepPartial<ActiveEffect.Data> & { _id: string })[]
              | (DeepPartial<DS4ItemData> & { _id: string })
              | (DeepPartial<DS4ItemData> & { _id: string })[],
    options?: Entity.UpdateOptions,
) {
    if (embeddedName === "OwnedItem") {
        const itemDataArray =
            data instanceof Array
                ? data.map((it) => expandObject(it) as DS4ItemData)
                : [expandObject(data as Record<string, unknown>) as DS4ItemData];
        preUpdateOwnedItem.bind(this)(itemDataArray);
        // eslint-disable-next-line
        // @ts-ignore
        return oldTokenUpdateEmbeddedEntity.bind(this)(embeddedName, itemDataArray, options);
    }
    // eslint-disable-next-line
    // @ts-ignore
    return oldTokenUpdateEmbeddedEntity.bind(this)(embeddedName, data, options);
}

ActorTokenHelpers.prototype.createEmbeddedEntity = tokenCreateEmbeddedEntity;
ActorTokenHelpers.prototype.updateEmbeddedEntity = tokenUpdateEmbeddedEntity;