import {getPartLocation, withCamera} from "./layout.ts";
import {AlignX, Point, Rect, Size} from "./engine/datatypes.ts";
import {DrawPile} from "./drawpile.ts";
import {D} from "./engine/public.ts";
import {BG_INSET, FG_BOLD, FG_TEXT} from "./colors.ts";
import {addButton} from "./button.ts";
import {
  getSkills,
} from "./skills.ts";
import {getPlayerProgress} from "./playerprogress.ts";
import {Skill, SkillData} from "./datatypes.ts";

export class SkillsModal {
  #drawpile: DrawPile;
  #shown: boolean;
  #skillSelection: Skill | null;

  constructor() {
    this.#drawpile = new DrawPile();
    this.#shown = false;
    this.#skillSelection = null;
  }

  get #size(): Size {
    // Instead of calculating this here, compute it from outside
    // as it has to be the same for every bottom modal
    return getPartLocation("BottomModal").size
  }

  get isShown(): boolean {
    return this.#shown;
  }

  setShown(shown: boolean) {
    this.#shown = shown
  }

  update() {
    withCamera("BottomModal", () => this.#update())
  }

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

  #update() {
    this.#drawpile.clear();
    let size = this.#size
    this.#drawpile.add(0, () => {
      D.fillRect(new Point(-4, -4), size.add(new Size(8, 8)), BG_INSET)
    })

    // draw skills
    let availableSkills = getPlayerProgress().getAvailableSkills();

    this.#fixSkillSelection(availableSkills);

    let y = 0;
    for (let skill of availableSkills) {
      let data = getSkills().get(skill);
      let cost = getSkills().computeCost(skill);
      let y_ = y;
      let selected = this.#skillSelection?.id == skill.id;
      let skillRect = new Rect(new Point(0,  y_), new Size(160 + 4, 16));
      let enabled = true;

      this.#drawpile.addClickable(
        0,
        (hover) => {
          // two column layout
          let [bg, fg] = [BG_INSET, FG_TEXT];
          if (selected || hover) {
            [bg, fg] = [FG_BOLD, BG_INSET];
          }
          D.fillRect(skillRect.top, skillRect.size, bg);
          D.drawText(data.profile.name, new Point(4, y_), fg);
          D.drawText("" + cost, new Point(160 - 4, y_), fg, {alignX: AlignX.Right});
        },
        skillRect,
        enabled,
        () => {
          this.#skillSelection = skill;
        }
      )
      y += 16;
    }

    // add skill description
    let selection = this.#skillSelection;
    if (selection != null) {
      let data = getSkills().get(selection);
      let cost = getSkills().computeCost(selection);
      let size = this.#size;
      let remainingWidth = size.w - 160;

      this.#drawpile.add(0, () => {
        D.fillRect(new Point(160, 0), new Size(remainingWidth, 96), FG_BOLD)
        D.drawText(createFullDescription(data), new Point(164, 0), BG_INSET, {forceWidth: remainingWidth - 8});
      });

      // add learn button
      let drawButtonRect = new Rect(new Point(160, 96), new Size(remainingWidth, 32))
      let canAfford = getPlayerProgress().getExperience() >= cost;
      let caption = `Learn ${data.profile.name}`
      if (!canAfford) {
        caption = `Can't Afford`;
      }

      addButton(this.#drawpile, caption, drawButtonRect, canAfford, () => {
        getPlayerProgress().spendExperience(cost);
        getPlayerProgress().learnSkill(selection);
      })
    }


    // add close button
    let closeRect = new Rect(new Point(0, 96), new Size(160, 32))
    addButton(this.#drawpile, "Back", closeRect, true, () => {
      this.setShown(false);
    })
    this.#drawpile.executeOnClick();
  }

  #fixSkillSelection(skills: Skill[]) {
    // if we have selected a skill that is really available,
    // that's fine
    for (let s of skills.values()) {
      if (s.id == this.#skillSelection?.id) {
        return;
      }
    }

    // select the first skill if one exists
    if (skills.length == 0) {
      this.#skillSelection = null;
    } else {
      this.#skillSelection = skills[0];
    }
  }

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

let active = new SkillsModal();

export function getSkillsModal(): SkillsModal {
  return active;
}

function createFullDescription(data: SkillData) {
  return data.profile.description + "\n\n" + data.governing.note
}