import { describe, expect, it } from "vitest";
import { recallKnowledge } from "../recall-knowledge.js";

describe("recallKnowledge", () => {
	it("returns null when no type trait is recognized", () => {
		expect(recallKnowledge(5, ["small", "goblin"])).toBeNull();
	});

	it("calculates DC for a common creature from the DC-by-level table", () => {
		const result = recallKnowledge(5, ["humanoid"]);
		expect(result).toEqual({ dc: 20, type: "humanoid", skills: ["Society"] });
	});

	it("calculates DC for level -1", () => {
		const result = recallKnowledge(-1, ["humanoid"]);
		expect(result).toEqual({ dc: 13, type: "humanoid", skills: ["Society"] });
	});

	it("calculates DC for level 0", () => {
		const result = recallKnowledge(0, ["animal"]);
		expect(result).toEqual({ dc: 14, type: "animal", skills: ["Nature"] });
	});

	it("calculates DC for level 25 (max table entry)", () => {
		const result = recallKnowledge(25, ["dragon"]);
		expect(result).toEqual({ dc: 50, type: "dragon", skills: ["Arcana"] });
	});

	it("clamps DC for levels beyond the table", () => {
		const result = recallKnowledge(30, ["dragon"]);
		expect(result).toEqual({ dc: 50, type: "dragon", skills: ["Arcana"] });
	});

	it("adjusts DC for uncommon rarity (+2)", () => {
		const result = recallKnowledge(5, ["uncommon", "medium", "undead"]);
		expect(result).toEqual({
			dc: 22,
			type: "undead",
			skills: ["Religion"],
		});
	});

	it("adjusts DC for rare rarity (+5)", () => {
		const result = recallKnowledge(5, ["rare", "large", "dragon"]);
		expect(result).toEqual({ dc: 25, type: "dragon", skills: ["Arcana"] });
	});

	it("adjusts DC for unique rarity (+10)", () => {
		const result = recallKnowledge(5, ["unique", "medium", "humanoid"]);
		expect(result).toEqual({
			dc: 30,
			type: "humanoid",
			skills: ["Society"],
		});
	});

	it("returns multiple skills for beast type", () => {
		const result = recallKnowledge(3, ["beast"]);
		expect(result).toEqual({
			dc: 18,
			type: "beast",
			skills: ["Arcana", "Nature"],
		});
	});

	it("returns multiple skills for construct type", () => {
		const result = recallKnowledge(1, ["construct"]);
		expect(result).toEqual({
			dc: 15,
			type: "construct",
			skills: ["Arcana", "Crafting"],
		});
	});

	it("matches type traits case-insensitively", () => {
		const result = recallKnowledge(5, ["Humanoid"]);
		expect(result).toEqual({ dc: 20, type: "Humanoid", skills: ["Society"] });
	});

	it("uses the first matching type trait when multiple are present", () => {
		const result = recallKnowledge(7, ["large", "monitor", "protean"]);
		expect(result).toEqual({
			dc: 23,
			type: "monitor",
			skills: ["Religion"],
		});
	});

	it("preserves original trait casing in the returned type", () => {
		const result = recallKnowledge(1, ["Fey"]);
		expect(result?.type).toBe("Fey");
	});

	it("ignores common rarity (no adjustment)", () => {
		// "common" is not included in traits by the normalization pipeline
		const result = recallKnowledge(5, ["medium", "humanoid"]);
		expect(result?.dc).toBe(20);
	});
});