#!/usr/bin/env bun
/**
 * Crawl a manufacturer's website and upsert their products into the GearBox catalog.
 *
 * Usage:
 *   bun run scripts/crawl-manufacturer.ts --manufacturer=apidura
 *   bun run scripts/crawl-manufacturer.ts --manufacturer=canyon --dry-run
 *
 * Env vars required:
 *   ANTHROPIC_API_KEY  — Anthropic API key
 *   GEARBOX_URL        — Base URL of the GearBox instance (default: http://localhost:3000)
 *   GEARBOX_API_KEY    — GearBox API key with write access
 */

import Anthropic from "@anthropic-ai/sdk";
import { CATEGORIES } from "./taxonomy/categories.ts";
import { TAGS } from "./taxonomy/tags.ts";

const GEARBOX_URL = process.env.GEARBOX_URL ?? "http://localhost:3000";
const GEARBOX_API_KEY = process.env.GEARBOX_API_KEY ?? "";
const ANTHROPIC_API_KEY = process.env.ANTHROPIC_API_KEY ?? "";
const MODEL = "claude-haiku-4-5-20251001";
const MAX_TOOL_ROUNDS = 30; // safety limit

// ── Parse CLI args ────────────────────────────────────────────────

const args = Object.fromEntries(
	process.argv
		.slice(2)
		.filter((a) => a.startsWith("--"))
		.map((a) => {
			const [k, v] = a.slice(2).split("=");
			return [k, v ?? "true"];
		}),
);

const manufacturerSlug = args["manufacturer"];
const dryRun = args["dry-run"] === "true";

if (!manufacturerSlug) {
	console.error("Usage: bun run scripts/crawl-manufacturer.ts --manufacturer=<slug>");
	process.exit(1);
}

if (!GEARBOX_API_KEY) {
	console.error("GEARBOX_API_KEY env var is required");
	process.exit(1);
}

if (!ANTHROPIC_API_KEY) {
	console.error("ANTHROPIC_API_KEY env var is required");
	process.exit(1);
}

// ── Fetch manufacturer from GearBox ──────────────────────────────

async function fetchManufacturer(slug: string) {
	const res = await fetch(`${GEARBOX_URL}/api/manufacturers/${slug}`);
	if (!res.ok) {
		throw new Error(`Manufacturer not found: ${slug} (HTTP ${res.status})`);
	}
	return res.json() as Promise<{
		id: number;
		name: string;
		slug: string;
		website: string;
		tier: number;
		country: string | null;
	}>;
}

// ── Tool: fetch a web page ────────────────────────────────────────

async function fetchPage(url: string): Promise<string> {
	try {
		const res = await fetch(url, {
			headers: {
				"User-Agent": "Mozilla/5.0 (compatible; GearBox-Catalog-Bot/1.0)",
				Accept: "text/html,application/xhtml+xml",
			},
			signal: AbortSignal.timeout(15_000),
		});
		if (!res.ok) return `HTTP ${res.status} for ${url}`;
		const html = await res.text();
		// Strip scripts, styles, and excessive whitespace for token efficiency
		return html
			.replace(/<script[^>]*>[\s\S]*?<\/script>/gi, "")
			.replace(/<style[^>]*>[\s\S]*?<\/style>/gi, "")
			.replace(/<!--[\s\S]*?-->/g, "")
			.replace(/\s{3,}/g, "  ")
			.slice(0, 60_000); // cap at 60k chars to stay within context
	} catch (err) {
		return `Error fetching ${url}: ${(err as Error).message}`;
	}
}

// ── Build system prompt ───────────────────────────────────────────

function buildSystemPrompt(manufacturer: Awaited<ReturnType<typeof fetchManufacturer>>) {
	return `You are a product data extraction agent for GearBox, a gear management app for bikepacking, cycling, and hiking.

Your task: crawl ${manufacturer.name}'s website (${manufacturer.website}) and extract their complete product catalog.

For each product, extract:
- model: string (product name WITHOUT the brand prefix)
- category: one of [${CATEGORIES.join(", ")}]
- weightGrams: number | null (weight in grams — convert if shown in oz/lbs/kg)
- priceCents: number | null (MSRP in cents, base currency)
- priceCurrency: string (ISO currency code — "EUR" for DE brands, "USD" for US, "GBP" for GB, etc.)
- description: string | null (1-3 sentence product description)
- sourceUrl: string (direct product page URL)
- tags: string[] (from this list only: [${TAGS.join(", ")}])

Rules:
- model must NOT include the brand name (e.g., "Terrapin System" not "Revelate Designs Terrapin System")
- Only include outdoor/adventure/cycling products. Skip accessories under €5, clothing if not relevant to the target categories.
- If weight is not listed on a product page, use null — do not guess.
- Assign 2-5 relevant tags per item.
- Extract every product in their catalog, not just featured ones. Navigate to all relevant subcategories.

When done, output a JSON array of product objects as your final message. Do not wrap in markdown — raw JSON only.

Example output:
[
  {
    "model": "Expedition Handlebar Pack",
    "category": "bags",
    "weightGrams": 300,
    "priceCents": 16000,
    "priceCurrency": "GBP",
    "description": "14L waterproof handlebar roll bag with internal dry bag and accessory pocket.",
    "sourceUrl": "https://apidura.com/shop/expedition-handlebar-pack/",
    "tags": ["bikepacking", "handlebar-bag", "bike-bag"]
  }
]`;
}

// ── Agentic tool-use loop ─────────────────────────────────────────

type CatalogItem = {
	model: string;
	category: string;
	weightGrams: number | null;
	priceCents: number | null;
	priceCurrency: string;
	description: string | null;
	sourceUrl: string;
	tags: string[];
};

async function runCrawlAgent(manufacturer: Awaited<ReturnType<typeof fetchManufacturer>>): Promise<CatalogItem[]> {
	const client = new Anthropic({ apiKey: ANTHROPIC_API_KEY });

	const tools: Anthropic.Tool[] = [
		{
			name: "fetch_page",
			description: "Fetch the HTML content of a URL. Use this to explore the manufacturer's website and product pages.",
			input_schema: {
				type: "object" as const,
				properties: {
					url: { type: "string", description: "The URL to fetch" },
				},
				required: ["url"],
			},
		},
	];

	const messages: Anthropic.MessageParam[] = [
		{
			role: "user",
			content: `Crawl ${manufacturer.name}'s website at ${manufacturer.website} and extract their complete product catalog. Start with the homepage or sitemap, navigate to all product categories, and return the full product list as JSON.`,
		},
	];

	let rounds = 0;

	while (rounds < MAX_TOOL_ROUNDS) {
		rounds++;
		console.log(`  [round ${rounds}] calling model...`);

		const response = await client.messages.create({
			model: MODEL,
			max_tokens: 8192,
			system: buildSystemPrompt(manufacturer),
			tools,
			messages,
		});

		// Add assistant response to history
		messages.push({ role: "assistant", content: response.content });

		if (response.stop_reason === "end_turn") {
			// Final message — extract JSON from text content
			const textBlock = response.content.find((b) => b.type === "text");
			if (!textBlock || textBlock.type !== "text") {
				throw new Error("Agent finished without text output");
			}
			return parseAgentOutput(textBlock.text);
		}

		if (response.stop_reason !== "tool_use") {
			throw new Error(`Unexpected stop reason: ${response.stop_reason}`);
		}

		// Process tool calls
		const toolResults: Anthropic.ToolResultBlockParam[] = [];
		for (const block of response.content) {
			if (block.type !== "tool_use") continue;
			if (block.name === "fetch_page") {
				const { url } = block.input as { url: string };
				console.log(`  [tool] fetch_page ${url}`);
				const content = await fetchPage(url);
				toolResults.push({
					type: "tool_result",
					tool_use_id: block.id,
					content,
				});
			}
		}

		messages.push({ role: "user", content: toolResults });
	}

	throw new Error(`Agent exceeded ${MAX_TOOL_ROUNDS} tool rounds without finishing`);
}

function parseAgentOutput(text: string): CatalogItem[] {
	// Handle agent wrapping output in markdown code blocks
	const cleaned = text.replace(/^```json\s*/i, "").replace(/\s*```$/i, "").trim();
	const parsed = JSON.parse(cleaned);
	if (!Array.isArray(parsed)) throw new Error("Agent output is not a JSON array");
	return parsed;
}

// ── Upsert to GearBox API ─────────────────────────────────────────

async function upsertItems(
	slug: string,
	items: CatalogItem[],
): Promise<{ created: number; updated: number }> {
	const payload = items.map((item) => ({
		manufacturerSlug: slug,
		model: item.model,
		category: item.category,
		weightGrams: item.weightGrams ?? undefined,
		priceCents: item.priceCents ?? undefined,
		description: item.description ?? undefined,
		sourceUrl: item.sourceUrl,
		tags: item.tags,
	}));

	// Chunk into batches of 100 (API limit)
	let totalCreated = 0;
	let totalUpdated = 0;

	for (let i = 0; i < payload.length; i += 100) {
		const batch = payload.slice(i, i + 100);
		const res = await fetch(`${GEARBOX_URL}/api/global-items/bulk`, {
			method: "POST",
			headers: {
				"Content-Type": "application/json",
				"X-API-Key": GEARBOX_API_KEY,
			},
			body: JSON.stringify({ items: batch }),
		});

		if (!res.ok) {
			const err = await res.text();
			throw new Error(`Bulk upsert failed (HTTP ${res.status}): ${err}`);
		}

		const result = await res.json() as { created: number; updated: number };
		totalCreated += result.created;
		totalUpdated += result.updated;
		console.log(`  batch ${Math.floor(i / 100) + 1}: +${result.created} new, ~${result.updated} updated`);
	}

	return { created: totalCreated, updated: totalUpdated };
}

// ── Main ──────────────────────────────────────────────────────────

async function main() {
	console.log(`\nCrawling manufacturer: ${manufacturerSlug}`);
	if (dryRun) console.log("DRY RUN — products will not be saved\n");

	const manufacturer = await fetchManufacturer(manufacturerSlug);
	console.log(`Found: ${manufacturer.name} (${manufacturer.website})\n`);

	console.log("Starting agent crawl...");
	const items = await runCrawlAgent(manufacturer);
	console.log(`\nAgent extracted ${items.length} products`);

	if (dryRun) {
		console.log("\nDry run output (first 3 items):");
		console.log(JSON.stringify(items.slice(0, 3), null, 2));
		return;
	}

	console.log("\nUpserting to catalog...");
	const { created, updated } = await upsertItems(manufacturerSlug, items);
	console.log(`\nDone: ${created} created, ${updated} updated`);
}

main().catch((err) => {
	console.error(err);
	process.exit(1);
});