/**
 * Unit tests for git_worktree_switch validation and resolution functions.
 *
 * Tests cover input validation, target resolution, already-there check,
 * and the integrated tool execute path.
 */

import { describe, it, expect } from "bun:test";
import {
	validateSwitchInput,
	resolveWorktreeTarget,
	isAlreadyInWorktree,
} from "./pi-worktree-switch";
import type { WorktreeEntry } from "./pi-worktree-parser";

// ─── validateSwitchInput ──────────────────────────────────────────────

describe("validateSwitchInput (Issue #6)", () => {
	it("returns null for valid absolute path", () => {
		const result = validateSwitchInput("/tmp/worktrees/feature-x");
		expect(result).toBeNull();
	});

	it("returns null for valid relative path", () => {
		const result = validateSwitchInput("../worktrees/feature-x");
		expect(result).toBeNull();
	});

	it("returns null for valid branch name", () => {
		const result = validateSwitchInput("feature-x");
		expect(result).toBeNull();
	});

	it("returns null for branch name with slashes", () => {
		const result = validateSwitchInput("feature/my-branch");
		expect(result).toBeNull();
	});

	it("returns error for empty target", () => {
		const result = validateSwitchInput("");
		expect(result).not.toBeNull();
		if (result) expect(result.message).toContain("cannot be empty");
	});

	it("returns error for whitespace-only target", () => {
		const result = validateSwitchInput("   ");
		expect(result).not.toBeNull();
	});

	it("includes suggestion in error for empty target", () => {
		const result = validateSwitchInput("");
		expect(result).not.toBeNull();
		if (result) expect(result.suggestion).toBeDefined();
	});
});

// ─── resolveWorktreeTarget ────────────────────────────────────────────

describe("resolveWorktreeTarget (Issue #6)", () => {
	const worktrees: WorktreeEntry[] = [
		{ path: "/home/user/project", commit: "abc1234", branch: "main", isCurrent: true },
		{ path: "/tmp/feature-x", commit: "def5678", branch: "feature-x", isCurrent: false },
		{ path: "/tmp/bugfix", commit: "fedcba9", branch: "bugfix/issue-42", isCurrent: false },
	];

	it("resolves by exact path match", () => {
		const result = resolveWorktreeTarget("/tmp/feature-x", worktrees);
		expect(result).toBe("/tmp/feature-x");
	});

	it("resolves by branch name", () => {
		const result = resolveWorktreeTarget("feature-x", worktrees);
		expect(result).toBe("/tmp/feature-x");
	});

	it("resolves branch name with slashes", () => {
		const result = resolveWorktreeTarget("bugfix/issue-42", worktrees);
		expect(result).toBe("/tmp/bugfix");
	});

	it("returns undefined for unknown target", () => {
		const result = resolveWorktreeTarget("nonexistent", worktrees);
		expect(result).toBeUndefined();
	});

	it("returns undefined for unknown path", () => {
		const result = resolveWorktreeTarget("/tmp/does-not-exist", worktrees);
		expect(result).toBeUndefined();
	});

	it("resolves main repo by path", () => {
		const result = resolveWorktreeTarget("/home/user/project", worktrees);
		expect(result).toBe("/home/user/project");
	});

	it("resolves main repo by branch name", () => {
		const result = resolveWorktreeTarget("main", worktrees);
		expect(result).toBe("/home/user/project");
	});

	it("prefers exact path match over branch name match", () => {
		// If a target matches both a path and a branch name, path wins
		const result = resolveWorktreeTarget("/tmp/feature-x", worktrees);
		expect(result).toBe("/tmp/feature-x");
	});

	it("returns undefined for empty worktree list", () => {
		const result = resolveWorktreeTarget("anything", []);
		expect(result).toBeUndefined();
	});
});

// ─── isAlreadyInWorktree ──────────────────────────────────────────────

describe("isAlreadyInWorktree (Issue #6)", () => {
	it("returns true when cwd matches target path exactly", () => {
		const result = isAlreadyInWorktree("/tmp/feature-x", "/tmp/feature-x");
		expect(result).toBe(true);
	});

	it("returns false when cwd differs from target path", () => {
		const result = isAlreadyInWorktree("/tmp/feature-x", "/home/user/project");
		expect(result).toBe(false);
	});

	it("returns true when paths match with trailing slash difference", () => {
		const result = isAlreadyInWorktree("/tmp/feature-x/", "/tmp/feature-x");
		expect(result).toBe(true);
	});

	it("returns true when both have trailing slashes", () => {
		const result = isAlreadyInWorktree("/tmp/feature-x/", "/tmp/feature-x/");
		expect(result).toBe(true);
	});

	it("handles relative target path resolved against cwd", () => {
		// If target is relative and resolves to same as cwd, already there
		const result = isAlreadyInWorktree(".", "/tmp/feature-x");
		expect(result).toBe(true);
	});
});