export async function fetchJson(url) {
	const res = await fetch(url, { cache: "no-store" });
	if (!res.ok) throw new Error(`HTTP ${res.status} for ${url}`);
	return await res.json();
}

export async function fetchText(url) {
	const res = await fetch(url, { cache: "no-store" });
	if (!res.ok) throw new Error(`HTTP ${res.status} for ${url}`);
	return await res.text();
}

export function inferGithubOwnerRepo() {
	const host = location.hostname || "";
	const m = host.match(/^([a-z0-9-]+)\.github\.io$/i);
	if (m) {
		const owner = m[1];
		const parts = (location.pathname || "/").split("/").filter(Boolean);
		const repo = parts.length >= 1 ? parts[0] : `${owner}.github.io`;
		return { owner, repo };
	}
	return { owner: "brennanwilkes", repo: "spirit-tracker" };
}

export function isLocalWriteMode() {
	const h = String(location.hostname || "").toLowerCase();
	return (
		(location.protocol === "http:" || location.protocol === "https:") && (h === "127.0.0.1" || h === "localhost")
	);
}

/* ---- Local disk-backed SKU link API (only on viz/serve.js) ---- */

export async function apiReadSkuMetaFromLocalServer() {
	const r = await fetch("/__stviz/sku-links", { cache: "no-store" });
	if (!r.ok) throw new Error(`HTTP ${r.status}`);
	const j = await r.json();
	return {
		links: Array.isArray(j?.links) ? j.links : [],
		ignores: Array.isArray(j?.ignores) ? j.ignores : [],
	};
}

export async function apiWriteSkuLink(fromSku, toSku) {
	const res = await fetch("/__stviz/sku-links", {
		method: "POST",
		headers: { "content-type": "application/json" },
		body: JSON.stringify({ fromSku, toSku }),
	});
	if (!res.ok) throw new Error(`HTTP ${res.status}`);
	return await res.json();
}

export async function apiWriteSkuIgnore(skuA, skuB) {
	const res = await fetch("/__stviz/sku-ignores", {
		method: "POST",
		headers: { "content-type": "application/json" },
		body: JSON.stringify({ skuA, skuB }),
	});
	if (!res.ok) throw new Error(`HTTP ${res.status}`);
	return await res.json();
}

/**
 * Best-effort read of sku meta:
 *  - On GitHub Pages: expects file at viz/data/sku_links.json
 *  - On local server: reads via /__stviz/sku-links (disk)
 */
export async function loadSkuMetaBestEffort() {
	// 1) GitHub Pages / static deploy inside viz/
	try {
		const j = await fetchJson("./data/sku_links.json");
		return {
			links: Array.isArray(j?.links) ? j.links : [],
			ignores: Array.isArray(j?.ignores) ? j.ignores : [],
		};
	} catch {}

	// 2) alternate static path (in case you later serve viz under a subpath)
	try {
		const j = await fetchJson("/data/sku_links.json");
		return {
			links: Array.isArray(j?.links) ? j.links : [],
			ignores: Array.isArray(j?.ignores) ? j.ignores : [],
		};
	} catch {}

	// 3) Local server API (disk)
	try {
		return await apiReadSkuMetaFromLocalServer();
	} catch {}

	return { links: [], ignores: [] };
}

/* ---- GitHub history helpers ---- */

export async function githubListCommits({ owner, repo, branch, path }) {
	const base = `https://api.github.com/repos/${encodeURIComponent(owner)}/${encodeURIComponent(repo)}/commits`;
	const u1 = `${base}?sha=${encodeURIComponent(branch)}&path=${encodeURIComponent(path)}&per_page=100&page=1`;
	const page1 = await fetchJson(u1);

	if (Array.isArray(page1) && page1.length === 100) {
		const u2 = `${base}?sha=${encodeURIComponent(branch)}&path=${encodeURIComponent(path)}&per_page=100&page=2`;
		const page2 = await fetchJson(u2);
		return [...page1, ...(Array.isArray(page2) ? page2 : [])];
	}

	return Array.isArray(page1) ? page1 : [];
}

export async function githubFetchFileAtSha({ owner, repo, sha, path }) {
	const raw = `https://raw.githubusercontent.com/${encodeURIComponent(owner)}/${encodeURIComponent(repo)}/${encodeURIComponent(sha)}/${path}`;
	const txt = await fetchText(raw);
	return JSON.parse(txt);
}