import type { Result } from "../../types/result";
import { z } from "zod";
import { Err, Ok } from "../../types/result";

const scrapeResponseSchema = z.object({
    success: z.boolean().optional(),
    error: z.union([z.string(), z.object({ message: z.string() })]).optional(),
    message: z.string().optional(),
    data: z.unknown().optional(),
});

export const readFirecrawlResponse = async (response: Response): Promise<Result<string, string>> => {
    const context = `Firecrawl scrape (HTTP ${response.status})`;
    let body: unknown;
    try {
        body = await response.json();
    } catch {
        return Err(`${context}: received a non-JSON or unreadable response.`);
    }

    const parsed = scrapeResponseSchema.safeParse(body);
    if (!parsed.success) {
        return Err(`${context}: received an unexpected response format.`);
    }

    const payload = parsed.data;
    const providerError = typeof payload.error === "string" ? payload.error : payload.error?.message;
    if (!response.ok || payload.success === false || providerError) {
        return Err(`${context}: ${providerError || payload.message || response.statusText || "Scrape failed without an error message."}`);
    }
    const content = z.object({ markdown: z.string() }).safeParse(payload.data);
    if (!content.success || content.data.markdown.trim() === "") {
        return Err(`${context}: no Markdown content was returned for this URL.`);
    }
    return Ok(content.data.markdown);
};