import type { PlayerCharacter } from "@initiative/domain";
import { playerCharacterId } from "@initiative/domain";
import { beforeEach, describe, expect, it } from "vitest";
import {
	loadPlayerCharacters,
	savePlayerCharacters,
} from "../player-character-storage.js";

const STORAGE_KEY = "initiative:player-characters";

function createMockLocalStorage() {
	const store = new Map<string, string>();
	return {
		getItem: (key: string) => store.get(key) ?? null,
		setItem: (key: string, value: string) => store.set(key, value),
		removeItem: (key: string) => store.delete(key),
		clear: () => store.clear(),
		get length() {
			return store.size;
		},
		key: (_index: number) => null,
		store,
	};
}

function makePC(overrides?: Partial<PlayerCharacter>): PlayerCharacter {
	return {
		id: playerCharacterId("pc-1"),
		name: "Aragorn",
		ac: 16,
		maxHp: 120,
		color: "green",
		icon: "sword",
		...overrides,
	};
}

describe("player-character-storage", () => {
	let mockStorage: ReturnType<typeof createMockLocalStorage>;

	beforeEach(() => {
		mockStorage = createMockLocalStorage();
		Object.defineProperty(globalThis, "localStorage", {
			value: mockStorage,
			writable: true,
		});
	});

	describe("round-trip save/load", () => {
		it("saves and loads a single character", () => {
			const pc = makePC();
			savePlayerCharacters([pc]);
			const loaded = loadPlayerCharacters();
			expect(loaded).toEqual([pc]);
		});

		it("saves and loads multiple characters", () => {
			const pcs = [
				makePC({ id: playerCharacterId("pc-1"), name: "Aragorn" }),
				makePC({
					id: playerCharacterId("pc-2"),
					name: "Legolas",
					ac: 14,
					maxHp: 90,
					color: "blue",
					icon: "eye",
				}),
			];
			savePlayerCharacters(pcs);
			const loaded = loadPlayerCharacters();
			expect(loaded).toEqual(pcs);
		});
	});

	describe("empty storage", () => {
		it("returns empty array when no data exists", () => {
			expect(loadPlayerCharacters()).toEqual([]);
		});
	});

	describe("corrupt JSON", () => {
		it("returns empty array for invalid JSON", () => {
			mockStorage.setItem(STORAGE_KEY, "not-json{{{");
			expect(loadPlayerCharacters()).toEqual([]);
		});

		it("returns empty array for non-array JSON", () => {
			mockStorage.setItem(STORAGE_KEY, '{"foo": "bar"}');
			expect(loadPlayerCharacters()).toEqual([]);
		});
	});

	describe("per-character validation", () => {
		it("discards character with missing name", () => {
			mockStorage.setItem(
				STORAGE_KEY,
				JSON.stringify([
					{ id: "pc-1", ac: 10, maxHp: 50, color: "blue", icon: "sword" },
				]),
			);
			expect(loadPlayerCharacters()).toEqual([]);
		});

		it("discards character with empty name", () => {
			mockStorage.setItem(
				STORAGE_KEY,
				JSON.stringify([
					{
						id: "pc-1",
						name: "",
						ac: 10,
						maxHp: 50,
						color: "blue",
						icon: "sword",
					},
				]),
			);
			expect(loadPlayerCharacters()).toEqual([]);
		});

		it("discards character with invalid color", () => {
			mockStorage.setItem(
				STORAGE_KEY,
				JSON.stringify([
					{
						id: "pc-1",
						name: "Test",
						ac: 10,
						maxHp: 50,
						color: "neon",
						icon: "sword",
					},
				]),
			);
			expect(loadPlayerCharacters()).toEqual([]);
		});

		it("discards character with invalid icon", () => {
			mockStorage.setItem(
				STORAGE_KEY,
				JSON.stringify([
					{
						id: "pc-1",
						name: "Test",
						ac: 10,
						maxHp: 50,
						color: "blue",
						icon: "banana",
					},
				]),
			);
			expect(loadPlayerCharacters()).toEqual([]);
		});

		it("discards character with negative AC", () => {
			mockStorage.setItem(
				STORAGE_KEY,
				JSON.stringify([
					{
						id: "pc-1",
						name: "Test",
						ac: -1,
						maxHp: 50,
						color: "blue",
						icon: "sword",
					},
				]),
			);
			expect(loadPlayerCharacters()).toEqual([]);
		});

		it("discards character with maxHp of 0", () => {
			mockStorage.setItem(
				STORAGE_KEY,
				JSON.stringify([
					{
						id: "pc-1",
						name: "Test",
						ac: 10,
						maxHp: 0,
						color: "blue",
						icon: "sword",
					},
				]),
			);
			expect(loadPlayerCharacters()).toEqual([]);
		});

		it("keeps valid characters and discards invalid ones", () => {
			mockStorage.setItem(
				STORAGE_KEY,
				JSON.stringify([
					{
						id: "pc-1",
						name: "Valid",
						ac: 10,
						maxHp: 50,
						color: "blue",
						icon: "sword",
					},
					{
						id: "pc-2",
						name: "",
						ac: 10,
						maxHp: 50,
						color: "blue",
						icon: "sword",
					},
				]),
			);
			const loaded = loadPlayerCharacters();
			expect(loaded).toHaveLength(1);
			expect(loaded[0].name).toBe("Valid");
		});
	});

	describe("storage errors", () => {
		it("save silently catches errors", () => {
			Object.defineProperty(globalThis, "localStorage", {
				value: {
					setItem: () => {
						throw new Error("QuotaExceeded");
					},
					getItem: () => null,
				},
				writable: true,
			});
			expect(() => savePlayerCharacters([makePC()])).not.toThrow();
		});
	});
});