import { describe, expect, it } from "vitest";
import { applyCommand, activePlayer, displays, handLimit, sustainedOn, type GameState, type PlayerId } from "../src/game";
import type { CardInstance } from "../src/cards";
import { newGame, must, giveCard, toRound2, faceOff, castAt } from "./helpers";

/** Display a stone for a player during their turn. */
function displayStone(state: GameState, playerId: PlayerId, stoneId: string, slot = 0): GameState {
  const stone = giveCard(state, playerId, stoneId, "S" + stoneId, slot);
  return must(state, playerId, { type: "cast", instanceId: stone.instanceId });
}

describe("magic stones", () => {
  it("bloodstone shaves one point off every hit", () => {
    let { state } = newGame();
    state = toRound2(state);
    const { attacker, defender } = faceOff(state);
    // Defender displays bloodstone on their own turn first.
    state = must(state, attacker, { type: "endTurn", draw: 0 });
    state = displayStone(state, defender, "bloodstone");
    expect(displays(state.players.find((p) => p.id === defender)!, "bloodstone")).toBe(true);
    state = must(state, defender, { type: "endTurn", draw: 0 });

    const fb = giveCard(state, attacker, "fireball", "F", 1);
    state = castAt(state, attacker, defender, fb);
    expect(state.players.find((p) => p.id === defender)!.life).toBe(11); // 5-1
  });

  it("soulstone keeps the last three points safe from spells", () => {
    let { state } = newGame();
    state = toRound2(state);
    const { attacker, defender } = faceOff(state);
    state = must(state, attacker, { type: "endTurn", draw: 0 });
    state = displayStone(state, defender, "soulstone");
    const d = state.players.find((p) => p.id === defender)!;
    d.life = 5;
    state = must(state, defender, { type: "endTurn", draw: 0 });

    const fb = giveCard(state, attacker, "fireball", "F", 1);
    state = castAt(state, attacker, defender, fb);
    expect(state.players.find((p) => p.id === defender)!.life).toBe(3); // floored, not 0

    // But a punch (physical) can finish the job past the floor.
    state = must(state, attacker, { type: "endTurn", draw: 0 });
    state = must(state, defender, { type: "endTurn", draw: 0 });
    state = must(state, attacker, { type: "punch", targetId: defender });
    state = must(state, defender, { type: "pass" });
    expect(state.players.find((p) => p.id === defender)!.life).toBe(2);
  });

  it("brainstone draws two now and raises the hand limit to nine", () => {
    let { state } = newGame();
    const me = activePlayer(state).id;
    state = displayStone(state, me, "brainstone");
    const p = state.players.find((pl) => pl.id === me)!;
    expect(p.hand.length).toBe(9); // 7 - 1 slot replaced + kept + 2 drawn
    expect(handLimit(p)).toBe(9);
    // Re-displaying is refused (no double draw).
    const again = applyCommand(state, me, { type: "cast", instanceId: "brainstone#Sbrainstone" });
    expect(again.ok).toBe(false);
  });

  it("powerstone adds one to number cards; speedstone adds movement", () => {
    let { state } = newGame();
    state = toRound2(state);
    const { attacker, defender } = faceOff(state);
    state = displayStone(state, attacker, "powerstone");
    const lb = giveCard(state, attacker, "lightning-blast", "L", 1);
    giveCard(state, attacker, "number-3", "N", 2);
    state = castAt(state, attacker, defender, lb, { numberInstanceIds: ["number-3#N"] });
    expect(state.players.find((p) => p.id === defender)!.life).toBe(11); // 3+1

    // Speedstone: allowance 4 on the next turn. (The stunned defender's turn
    // is skipped, so play comes straight back to the attacker.)
    state = displayStone(state, attacker, "speedstone", 1);
    state = must(state, attacker, { type: "endTurn", draw: 0 });
    expect(activePlayer(state).id).toBe(attacker);
    expect(state.turn.movementAllowance).toBe(4);
  });

  it("shieldstone lets number cards counteract spells", () => {
    let { state } = newGame();
    state = toRound2(state);
    const { attacker, defender } = faceOff(state);
    state = must(state, attacker, { type: "endTurn", draw: 0 });
    state = displayStone(state, defender, "shieldstone");
    state = must(state, defender, { type: "endTurn", draw: 0 });

    const fb = giveCard(state, attacker, "fireball", "F", 1);
    giveCard(state, defender, "number-4", "N4", 1);
    state = must(state, attacker, {
      type: "cast", instanceId: fb.instanceId, target: { kind: "player", playerId: defender },
    });
    state = must(state, defender, { type: "counteract", instanceId: "number-4#N4" });
    state = must(state, attacker, { type: "pass" });
    state = must(state, defender, { type: "pass" });
    expect(state.players.find((p) => p.id === defender)!.life).toBe(14); // 5-4
  });

  it("shadowstone feeds physical damage back as life", () => {
    let { state } = newGame();
    state = toRound2(state);
    const { attacker, defender } = faceOff(state);
    state = displayStone(state, attacker, "shadowstone");
    const dagger = giveCard(state, attacker, "dagger", "D", 1);
    state = castAt(state, attacker, defender, dagger);
    expect(state.players.find((p) => p.id === defender)!.life).toBe(12);
    expect(state.players.find((p) => p.id === attacker)!.life).toBe(18); // +3
  });

  it("fireball burns displayed stones off when damage lands", () => {
    let { state } = newGame();
    state = toRound2(state);
    const { attacker, defender } = faceOff(state);
    state = must(state, attacker, { type: "endTurn", draw: 0 });
    state = displayStone(state, defender, "speedstone");
    state = must(state, defender, { type: "endTurn", draw: 0 });

    const fb = giveCard(state, attacker, "fireball", "F", 1);
    state = castAt(state, attacker, defender, fb);
    const d = state.players.find((p) => p.id === defender)!;
    expect(d.hand.some((c) => c.cardId === "speedstone")).toBe(false);
    expect(d.displayed.length).toBe(0);
  });
});

describe("slow death", () => {
  it("bleeds one life per card drawn, forever", () => {
    let { state } = newGame();
    state = toRound2(state);
    const { attacker, defender } = faceOff(state);
    const sd = giveCard(state, attacker, "slow-death");
    state = castAt(state, attacker, defender, sd);
    expect(sustainedOn(state, defender, "slow-death").length).toBe(1);

    state = must(state, attacker, { type: "endTurn", draw: 0 });
    // Defender discards two to make room, then draws two: 2 damage.
    const d = state.players.find((p) => p.id === defender)!;
    const toDiscard = d.hand.slice(0, 2).map((c) => c.instanceId);
    state = must(state, defender, { type: "discard", instanceIds: toDiscard });
    state = must(state, defender, { type: "endTurn", draw: 2 });
    expect(state.players.find((p) => p.id === defender)!.life).toBe(13);

    // It never expires — many turns later it still bleeds.
    for (let i = 0; i < 4; i++) {
      state = must(state, activePlayer(state).id, { type: "endTurn", draw: 0 });
    }
    expect(sustainedOn(state, defender, "slow-death").length).toBe(1);
  });

  it("bloodstone cancels slow death's per-draw point", () => {
    let { state } = newGame();
    state = toRound2(state);
    const { attacker, defender } = faceOff(state);
    const sd = giveCard(state, attacker, "slow-death");
    state = castAt(state, attacker, defender, sd);
    state = must(state, attacker, { type: "endTurn", draw: 0 });

    state = displayStone(state, defender, "bloodstone");
    const d = state.players.find((p) => p.id === defender)!;
    const toDiscard = d.hand.filter((c) => c.cardId !== "bloodstone").slice(0, 2).map((c) => c.instanceId);
    state = must(state, defender, { type: "discard", instanceIds: toDiscard });
    state = must(state, defender, { type: "endTurn", draw: 2 });
    expect(state.players.find((p) => p.id === defender)!.life).toBe(15); // 1-1=0 per draw
  });
});