// SPDX-FileCopyrightText: 2021 Johannes Loher
// SPDX-FileCopyrightText: 2021 Oliver Rümpelein
//
// SPDX-License-Identifier: MIT

import { DialogWithListeners } from "../apps/dialog-with-listeners";
import { DS4 } from "../config";
import { getGame } from "../helpers";

/**
 * Provides default values for all arguments the `CheckFactory` expects.
 */
class DefaultCheckOptions implements DS4CheckFactoryOptions {
    readonly maximumCoupResult = 1;
    readonly minimumFumbleResult = 20;
    readonly useSlayingDice = false;
    readonly rollMode: keyof CONFIG.Dice.RollModes = "publicroll";
    readonly flavor: undefined;

    mergeWith(other: Partial<DS4CheckFactoryOptions>): DS4CheckFactoryOptions {
        return { ...this, ...other };
    }
}

/**
 * Singleton reference for default value extraction.
 */
const defaultCheckOptions = new DefaultCheckOptions();

/**
 * Most basic class responsible for generating the chat formula and passing it to the chat as roll.
 */
class CheckFactory {
    constructor(
        private checkTargetNumber: number,
        private checkModifier: number,
        options: Partial<DS4CheckFactoryOptions> = {},
    ) {
        this.options = defaultCheckOptions.mergeWith(options);
    }

    private options: DS4CheckFactoryOptions;

    async execute(): Promise<ChatMessage | undefined> {
        const innerFormula = ["ds", this.createCheckTargetNumberModifier(), this.createCoupFumbleModifier()].filterJoin(
            "",
        );
        const formula = this.options.useSlayingDice ? `{${innerFormula}}x` : innerFormula;
        const roll = Roll.create(formula);
        const speaker = this.options.speaker ?? ChatMessage.getSpeaker();

        return roll.toMessage(
            {
                speaker,
                flavor: this.options.flavor,
                flags: this.options.flavorData ? { ds4: { flavorData: this.options.flavorData } } : undefined,
            },
            { rollMode: this.options.rollMode, create: true },
        );
    }

    createCheckTargetNumberModifier(): string {
        const totalCheckTargetNumber = Math.max(this.checkTargetNumber + this.checkModifier, 0);
        return `v${totalCheckTargetNumber}`;
    }

    createCoupFumbleModifier(): string | null {
        const isMinimumFumbleResultRequired =
            this.options.minimumFumbleResult !== defaultCheckOptions.minimumFumbleResult;
        const isMaximumCoupResultRequired = this.options.maximumCoupResult !== defaultCheckOptions.maximumCoupResult;

        if (isMinimumFumbleResultRequired || isMaximumCoupResultRequired) {
            return `c${this.options.maximumCoupResult ?? ""}:${this.options.minimumFumbleResult ?? ""}`;
        } else {
            return null;
        }
    }
}

/**
 * Asks the user for all unknown/necessary information and passes them on to perform a roll.
 * @param checkTargetNumber - The Check Target Number ("CTN")
 * @param options           - Options changing the behavior of the roll and message.
 */
export async function createCheckRoll(
    checkTargetNumber: number,
    options: Partial<DS4CheckFactoryOptions> = {},
): Promise<ChatMessage | unknown> {
    // Ask for additional required data;
    const interactiveRollData = await askForInteractiveRollData(checkTargetNumber, options);

    const newTargetValue = interactiveRollData.checkTargetNumber ?? checkTargetNumber;
    const checkModifier = interactiveRollData.checkModifier ?? 0;
    const newOptions: Partial<DS4CheckFactoryOptions> = {
        maximumCoupResult: interactiveRollData.maximumCoupResult ?? options.maximumCoupResult,
        minimumFumbleResult: interactiveRollData.minimumFumbleResult ?? options.minimumFumbleResult,
        useSlayingDice: getGame().settings.get("ds4", "useSlayingDiceForAutomatedChecks"),
        rollMode: interactiveRollData.rollMode ?? options.rollMode,
        flavor: options.flavor,
        flavorData: options.flavorData,
        speaker: options.speaker,
    };

    // Create Factory
    const cf = new CheckFactory(newTargetValue, checkModifier, newOptions);

    // Possibly additional processing

    // Execute roll
    return cf.execute();
}

/**
 * Responsible for rendering the modal interface asking for the check modifier and (currently) additional
 * data.
 *
 * @notes
 * At the moment, this asks for more data than it will do after some iterations.
 *
 * @returns The data given by the user.
 */
async function askForInteractiveRollData(
    checkTargetNumber: number,
    options: Partial<DS4CheckFactoryOptions> = {},
    { template, title }: { template?: string; title?: string } = {},
): Promise<Partial<IntermediateInteractiveRollData>> {
    const usedTemplate = template ?? "systems/ds4/templates/dialogs/roll-options.hbs";
    const usedTitle = title ?? getGame().i18n.localize("DS4.DialogRollOptionsDefaultTitle");
    const id = foundry.utils.randomID();
    const templateData = {
        title: usedTitle,
        checkTargetNumber: checkTargetNumber,
        maximumCoupResult: options.maximumCoupResult ?? defaultCheckOptions.maximumCoupResult,
        minimumFumbleResult: options.minimumFumbleResult ?? defaultCheckOptions.minimumFumbleResult,
        rollMode: options.rollMode ?? getGame().settings.get("core", "rollMode"),
        rollModes: CONFIG.Dice.rollModes,
        checkModifiers: Object.entries(DS4.i18n.checkModifiers).map(([key, translation]) => {
            if (key in DS4.checkModifiers) {
                const value = DS4.checkModifiers[key as keyof typeof DS4.checkModifiers];
                const label = `${translation} (${value >= 0 ? `+${value}` : value})`;
                return { value, label };
            }
            return { value: key, label: translation };
        }),
        id,
    };
    const renderedHtml = await renderTemplate(usedTemplate, templateData);

    const dialogPromise = new Promise<HTMLFormElement>((resolve) => {
        new DialogWithListeners(
            {
                title: usedTitle,
                content: renderedHtml,
                buttons: {
                    ok: {
                        icon: '<i class="fas fa-check"></i>',
                        label: getGame().i18n.localize("DS4.GenericOkButton"),
                        callback: (html) => {
                            if (!("jquery" in html)) {
                                throw new Error(
                                    getGame().i18n.format("DS4.ErrorUnexpectedHtmlType", {
                                        exType: "JQuery",
                                        realType: "HTMLElement",
                                    }),
                                );
                            } else {
                                const innerForm = html[0]?.querySelector("form");
                                if (!innerForm) {
                                    throw new Error(
                                        getGame().i18n.format("DS4.ErrorCouldNotFindHtmlElement", {
                                            htmlElement: "form",
                                        }),
                                    );
                                }
                                resolve(innerForm);
                            }
                        },
                    },
                    cancel: {
                        icon: '<i class="fas fa-times"></i>',
                        label: getGame().i18n.localize("DS4.GenericCancelButton"),
                    },
                },
                default: "ok",
            },
            {
                activateAdditionalListeners: (html, app) => {
                    const checkModifierCustomFormGroup = html
                        .find(`#check-modifier-custom-${id}`)
                        .parent(".form-group");
                    html.find(`#check-modifier-${id}`).on("change", (event) => {
                        if (
                            (event.currentTarget as HTMLSelectElement).value === "custom" &&
                            checkModifierCustomFormGroup.hasClass("ds4-hidden")
                        ) {
                            checkModifierCustomFormGroup.removeClass("ds4-hidden");
                            app.setPosition({ height: "auto" });
                        } else if (!checkModifierCustomFormGroup.hasClass("ds4-hidden")) {
                            checkModifierCustomFormGroup.addClass("ds4-hidden");
                            app.setPosition({ height: "auto" });
                        }
                    });
                },
                id,
            },
        ).render(true);
    });
    const dialogForm = await dialogPromise;
    return parseDialogFormData(dialogForm);
}

/**
 * Extracts Dialog data from the returned DOM element.
 * @param formData - The filed dialog
 */
function parseDialogFormData(formData: HTMLFormElement): Partial<IntermediateInteractiveRollData> {
    const chosenCheckTargetNumber = parseInt(formData["check-target-number"]?.value);
    const chosenCheckModifier = formData["check-modifier"]?.value;

    const chosenCheckModifierValue =
        chosenCheckModifier === "custom"
            ? parseInt(formData["check-modifier-custom"]?.value)
            : parseInt(chosenCheckModifier);

    const chosenMaximumCoupResult = parseInt(formData["maximum-coup-result"]?.value);
    const chosenMinimumFumbleResult = parseInt(formData["minimum-fumble-result"]?.value);
    const chosenRollMode = formData["roll-mode"]?.value;

    return {
        checkTargetNumber: Number.isSafeInteger(chosenCheckTargetNumber) ? chosenCheckTargetNumber : undefined,
        checkModifier: Number.isSafeInteger(chosenCheckModifierValue) ? chosenCheckModifierValue : undefined,
        maximumCoupResult: Number.isSafeInteger(chosenMaximumCoupResult) ? chosenMaximumCoupResult : undefined,
        minimumFumbleResult: Number.isSafeInteger(chosenMinimumFumbleResult) ? chosenMinimumFumbleResult : undefined,
        rollMode: Object.keys(CONFIG.Dice.rollModes).includes(chosenRollMode) ? chosenRollMode : undefined,
    };
}

/**
 * Contains data that needs retrieval from an interactive Dialog.
 */
interface InteractiveRollData {
    checkModifier: number;
    rollMode: keyof CONFIG.Dice.RollModes;
}

/**
 * Contains *CURRENTLY* necessary Data for drafting a roll.
 *
 * @deprecated
 * Quite a lot of this information is requested due to a lack of automation:
 *  - maximumCoupResult
 *  - minimumFumbleResult
 *  - checkTargetNumber
 *
 * They will and should be removed once effects and data retrieval is in place.
 * If a "raw" roll dialog is necessary, create another pre-processing Dialog
 * class asking for the required information.
 * This interface should then be replaced with the `InteractiveRollData`.
 */
interface IntermediateInteractiveRollData extends InteractiveRollData {
    checkTargetNumber: number;
    maximumCoupResult: number;
    minimumFumbleResult: number;
}

/**
 * The minimum behavioral options that need to be passed to the factory.
 */
export interface DS4CheckFactoryOptions {
    maximumCoupResult: number;
    minimumFumbleResult: number;
    useSlayingDice: boolean;
    rollMode: keyof CONFIG.Dice.RollModes;
    flavor?: string;
    flavorData?: Record<string, string | number | null>;
    speaker?: ReturnType<typeof ChatMessage.getSpeaker>;
}