import { getCsrfToken } from "$lib/auth";

export const API_BASE_URL = "http://localhost:8000/api";

export async function fetchAPI<T>(endpoint: string, options: RequestInit = {}): Promise<T> {
    let csrfToken = await getCsrfToken();
    if (!csrfToken) {
        console.warn("CSRF token not found, using empty string.");
        csrfToken = "";
    }
    const url = `${API_BASE_URL}${endpoint}`;
    options.credentials = "include"; // Include cookies in the request
    options.headers = {
        ...options.headers,
        "Content-Type": "application/json",
        "X-CSRFToken": csrfToken,
    };
    try {
        const response = await fetch(url, options);
        if (!response.ok) {
            let errorText = await response.json();
            if (
                errorText &&
                typeof errorText === "object" &&
                ("detail" in errorText || "field_errors" in errorText || "non_field_errors" in errorText)
            ) {
                // Handle structured error responses
                if ("detail" in errorText) {
                    errorText = errorText.detail;
                } else if ("field_errors" in errorText) {
                    errorText = Object.values(errorText.field_errors).join(", ");
                } else if ("non_field_errors" in errorText) {
                    errorText = errorText.non_field_errors.join(", ");
                }
            } else {
                errorText = `Unexpected error: ${response.statusText}`;
            }
            throw new Error(`${errorText}`);
        }
        if (response.status === 204) {
            // No content response
            return {} as T; // Return an empty object for 204 responses
        }
        return (await response.json()) as T;
    } catch (error) {
        console.error(`Error fetching ${url}:`, error);
        if (error instanceof Error) {
            // If the error is an instance of Error, rethrow it
            return Promise.reject(new Error(`${error.message}`));
        }
        return Promise.reject(new Error(`${error}`));
    }
}

export function postAPI<T>(endpoint: string, data: any): Promise<T> {
    return fetchAPI<T>(endpoint, {
        method: "POST",
        headers: {
            "Content-Type": "application/json",
        },
        body: JSON.stringify(data),
    });
}

export function getAPI<T>(endpoint: string): Promise<T> {
    return fetchAPI<T>(endpoint, {
        method: "GET",
    });
}

export function putAPI<T>(endpoint: string, data: any): Promise<T> {
    return fetchAPI<T>(endpoint, {
        method: "PUT",
        headers: {
            "Content-Type": "application/json",
        },
        body: JSON.stringify(data),
    });
}

export function deleteAPI<T>(endpoint: string): Promise<T> {
    return fetchAPI<T>(endpoint, {
        method: "DELETE",
    });
}