import {describe, expect, it} from "bun:test";
import {classifyLines} from "../src/markdownStructure";

describe("classifyLines – plain content", () => {
	it("classifies all lines as content when there is no frontmatter or code", () => {
		const input = "# Title\n\n- [ ] open\n- text\n";
		expect(classifyLines(input)).toEqual([
			"content",
			"content",
			"content",
			"content",
			"content",
		]);
	});
});

describe("classifyLines – fenced code blocks", () => {
	it("classifies backtick-fenced lines as code", () => {
		const input = ["before", "```", "- [ ] not a task", "```", "after"].join("\n");
		expect(classifyLines(input)).toEqual(["content", "code", "code", "code", "content"]);
	});

	it("classifies tilde-fenced lines as code", () => {
		const input = ["before", "~~~", "- [ ] not a task", "~~~", "after"].join("\n");
		expect(classifyLines(input)).toEqual(["content", "code", "code", "code", "content"]);
	});

	it("supports info strings on the opening fence", () => {
		const input = ["```markdown", "- [ ] not a task", "```"].join("\n");
		expect(classifyLines(input)).toEqual(["code", "code", "code"]);
	});

	it("does not close on a shorter fence", () => {
		const input = ["````", "```", "still in code", "````"].join("\n");
		expect(classifyLines(input)).toEqual(["code", "code", "code", "code"]);
	});

	it("does not treat tilde and backtick fences as matching", () => {
		const input = ["```", "~~~", "still code"].join("\n");
		expect(classifyLines(input)).toEqual(["code", "code", "code"]);
	});

	it("treats a closing fence with trailing whitespace as a closer", () => {
		const input = ["```", "x", "```   ", "after"].join("\n");
		expect(classifyLines(input)).toEqual(["code", "code", "code", "content"]);
	});

	it("does not treat a fence with info string as a closer", () => {
		const input = ["```", "x", "``` not-a-closer", "still", "```"].join("\n");
		expect(classifyLines(input)).toEqual(["code", "code", "code", "code", "code"]);
	});

	it("permits up to 3 spaces of indentation on the fence", () => {
		const input = ["   ```", "- [ ] not a task", "   ```", "after"].join("\n");
		expect(classifyLines(input)).toEqual(["code", "code", "code", "content"]);
	});
});

describe("classifyLines – frontmatter", () => {
	it("treats opening --- only at the very first line", () => {
		const input = ["---", "Pending tasks: true", "---", "- [ ] open"].join("\n");
		expect(classifyLines(input)).toEqual([
			"frontmatter",
			"frontmatter",
			"frontmatter",
			"content",
		]);
	});

	it("does not treat a --- elsewhere as frontmatter", () => {
		const input = ["# Title", "---", "- [ ] open"].join("\n");
		expect(classifyLines(input)).toEqual(["content", "content", "content"]);
	});

	it("supports the YAML ... terminator", () => {
		const input = ["---", "key: value", "...", "- [ ] open"].join("\n");
		expect(classifyLines(input)).toEqual([
			"frontmatter",
			"frontmatter",
			"frontmatter",
			"content",
		]);
	});
});

describe("classifyLines – combined", () => {
	it("handles frontmatter followed by content with a code block", () => {
		const input = [
			"---",
			"foo: bar",
			"---",
			"- [ ] real task",
			"```",
			"- [ ] not a task",
			"```",
			"- [ ] another real task",
		].join("\n");
		expect(classifyLines(input)).toEqual([
			"frontmatter",
			"frontmatter",
			"frontmatter",
			"content",
			"code",
			"code",
			"code",
			"content",
		]);
	});
});