import { D, I } from "./engine/public.ts";
import { AlignX, AlignY, Point, Rect, Size } from "./engine/datatypes.ts";
import { withCamera } from "./layout.ts";
import { VNScene, VNSceneMessage, VNScenePart } from "./vnscene.ts";
import { C } from "./colors.ts";
import { DrawPile } from "./drawpile.ts";
import { wipeSaves } from "./save.ts";
import { SaveFileV1 } from "./saveformat.ts";
import { addButton } from "./button.ts";
import { getStateManager } from "./statemanager.ts";

const WIDTH = 384;
const HEIGHT = 384;

export class VNModal {
  #scene: VNScene | null;
  #nextIndex = 0;
  #cathexis: SceneCathexis | null;

  constructor() {
    this.#scene = null;
    this.#nextIndex = 0;
    this.#cathexis = null;
  }

  get blocksHud(): boolean {
    return true;
  }

  get isShown(): boolean {
    return this.#scene != null;
  }

  play(scene: VNScene) {
    this.#scene = scene;
    this.#nextIndex = 0;
    this.#cathexis = null;

    this.#fixCathexis();
  }

  #fixCathexis() {
    while (true) {
      if (this.#cathexis?.isDone()) {
        this.#cathexis = null;
      }
      if (this.#cathexis != null) {
        return;
      }

      if (this.#scene == null) {
        return;
      }
      if (this.#cathexis == null) {
        let ix = this.#nextIndex;
        if (ix < this.#scene?.length) {
          this.#cathexis = createCathexis(this.#scene[ix]);
          this.#nextIndex += 1;
        } else {
          this.#scene = null;
        }
      }
    }
  }

  update() {
    this.#fixCathexis();
    withCamera("FullscreenPopover", () => this.#update());
  }

  draw() {
    withCamera("FullscreenPopover", () => this.#draw());
  }

  #update() {
    this.#cathexis?.update();
  }

  #draw() {
    this.#cathexis?.draw();
  }
}

interface SceneCathexis {
  isDone(): boolean;
  update(): void;
  draw(): void;
}

function createCathexis(part: VNScenePart): SceneCathexis {
  switch (part.type) {
    case "message":
      part?.sfx?.play({ volume: 0.5 });
      return new SceneMessageCathexis(part);
    case "callback":
      part?.callback();
      return new SkipCathexis();
    case "saveGameScreen":
      return new SaveGameCathexis(part.file, part.error);
  }
}

class SceneMessageCathexis {
  #message: VNSceneMessage;
  #done: boolean;
  #gotOneFrame: boolean;

  constructor(message: VNSceneMessage) {
    this.#message = message;
    this.#done = false;
    this.#gotOneFrame = false;
  }

  isDone() {
    return this.#done;
  }

  update() {
    let firstFrame = !this.#gotOneFrame;
    this.#gotOneFrame = true;

    if (!firstFrame && I.isMouseClicked("leftMouse")) {
      this.#done = true;
    }
  }

  draw() {
    D.drawText(
      this.#message.text,
      new Point(WIDTH / 2, HEIGHT / 2),
      C.FG_BOLD,
      {
        alignX: AlignX.Center,
        alignY: AlignY.Middle,
        forceWidth: WIDTH,
      },
    );
  }
}

let active: VNModal = new VNModal();
export function getVNModal() {
  return active;
}

class SkipCathexis {
  constructor() {}

  isDone() {
    return true;
  }

  update() {
    throw new Error("shouldn't be updated");
  }

  draw() {
    throw new Error("shouldn't ever be drawn");
  }
}

class SaveGameCathexis {
  #drawpile: DrawPile;
  #file: SaveFileV1 | null;
  #error: string | null;
  #done: boolean;

  constructor(file: SaveFileV1 | null, error: string | null) {
    this.#drawpile = new DrawPile();
    this.#file = file;
    this.#error = error;
    this.#done = false;
  }

  isDone() {
    return this.#done;
  }

  update() {
    let name = this.#file?.name;
    let turn = this.#file?.turn ?? 0;
    let turnText = turn < 9 ? `${name}, Turn ${turn + 1}` : "Sentence of Fate";
    this.#drawpile.clear();
    this.#drawpile.add(0, () => {
      D.drawText(
        this.#error && this.#file
          ? `A save was invalid. Continue from an alternate save?

${this.#error}`
          : this.#error
            ? `Your save was invalid:

${this.#error}`
          : "Resume from save?",
        new Point(WIDTH / 2, HEIGHT / 2),
        C.FG_BOLD,
        {
          alignX: AlignX.Center,
          alignY: AlignY.Middle,
          forceWidth: WIDTH,
        },
      );
    });

    addButton(
      this.#drawpile,
      "Clear Save",
      new Rect(new Point(0, HEIGHT - 32), new Size(128, 32)),
      this.#file != null,
      () => {
        wipeSaves();
        this.#file = null;
      },
    );
    if (this.#file) {
      let file = this.#file;
      addButton(
        this.#drawpile,
        `Continue (${turnText})`,
        new Rect(new Point(128, HEIGHT - 32), new Size(WIDTH - 128, 32)),
        true,
        () => {
          getStateManager().resumeGame(file);
          this.#done = true;
        },
      );
    } else {
      addButton(
        this.#drawpile,
        `Start New Game`,
        new Rect(new Point(128, HEIGHT - 32), new Size(WIDTH - 128, 32)),
        true,
        () => {
          getStateManager().startFirstGame();
          this.#done = true;
        },
      );
    }
    this.#drawpile.executeOnClick();
  }

  draw() {
    this.#drawpile.draw();
  }
}