import {Temporal} from "@js-temporal/polyfill";
import {clear_session_data} from "$shared/lib/session";
import {resolve_references} from "$shared/lib/helpers";
import {replace} from "svelte-spa-router";
import type {IInternalFetchResponse} from "$shared/lib/models/IInternalFetchResponse";
import type {IInternalFetchRequest} from "$shared/lib/models/IInternalFetchRequest";

export async function http_post(url: string, body?: object|string, timeout = -1, skip_401_check = false, abort_signal: AbortSignal = undefined): Promise<IInternalFetchResponse> {
    const init = {
        method: "post",
    } as RequestInit;

    if (abort_signal) {
        init.signal = abort_signal;
    }

    if (body) {
        init.headers = {
            "Content-Type": "application/json;charset=UTF-8",
        };
        init.body = JSON.stringify(body);
    }

    const response = await internal_fetch({url, init, timeout});
    const result = {} as IInternalFetchResponse;

    if (!skip_401_check && await is_401(response)) return result;

    result.ok = response.ok;
    result.status = response.status;
    result.http_response = response;

    if (response.status !== 204) {
        try {
            const ct = response.headers.get("Content-Type")?.toString() ?? "";
            if (ct.startsWith("application/json")) {
                const data = await response.json();
                result.data = resolve_references(data);
            } else if (ct.startsWith("text/plain")) {
                const text = await response.text();
                result.data = text as string;
            }
        } catch {
            // Ignored
        }
    }

    return result;
}

export async function http_get(url: string, timeout = -1, skip_401_check = false, abort_signal: AbortSignal = undefined): Promise<IInternalFetchResponse> {
    const init = {
        method: "get",
    } as RequestInit;

    if (abort_signal) {
        init.signal = abort_signal;
    }

    const response = await internal_fetch({url, init, timeout});
    const result = {} as IInternalFetchResponse;

    if (!skip_401_check && await is_401(response)) return result;

    result.ok = response.ok;
    result.status = response.status;
    result.http_response = response;

    if (response.status !== 204) {
        try {
            const ct = response.headers.get("Content-Type")?.toString() ?? "";
            if (ct.startsWith("application/json")) {
                const data = await response.json();
                result.data = resolve_references(data);
            } else if (ct.startsWith("text/plain")) {
                const text = await response.text();
                result.data = text as string;
            }
        } catch {
            // Ignored
        }
    }

    return result;
}

export async function http_delete(url: string, body?: object|string, timeout = -1, skip_401_check = false, abort_signal: AbortSignal = undefined): Promise<IInternalFetchResponse> {
    const init = {
        method: "delete",
    } as RequestInit;

    if (abort_signal) {
        init.signal = abort_signal;
    }

    if (body) {
        init.headers = {
            "Content-Type": "application/json;charset=UTF-8",
        };
        init.body = JSON.stringify(body);
    }

    const response = await internal_fetch({url, init, timeout});
    const result = {} as IInternalFetchResponse;

    if (!skip_401_check && await is_401(response)) return result;

    result.ok = response.ok;
    result.status = response.status;
    result.http_response = response;

    if (response.status !== 204) {
        try {
            const ct = response.headers.get("Content-Type")?.toString() ?? "";
            if (ct.startsWith("application/json")) {
                const data = await response.json();
                result.data = resolve_references(data);
            } else if (ct.startsWith("text/plain")) {
                const text = await response.text();
                result.data = text as string;
            }
        } catch (error) {
            // ignored
        }
    }

    return result;
}

async function internal_fetch(request: IInternalFetchRequest): Promise<Response> {
    if (!request.init) request.init = {};
    request.init.credentials = "include";
    request.init.headers = {
        "X-TimeZone": Temporal.Now.timeZone().id,
        ...request.init.headers
    };

    const fetch_request = new Request(request.url, request.init);
    let response: any;

    try {
        if (request.timeout > 500) {
            response = await Promise.race([
                fetch(fetch_request),
                new Promise((_, reject) => setTimeout(() => reject(new Error("Timeout")), request.timeout))
            ]);
        } else {
            response = await fetch(fetch_request);
        }
    } catch (error) {
        if (error.message === "Timeout") {
            console.error("Request timed out");
        } else if (error.message === "Network request failed") {
            console.error("No internet connection");
        } else {
            throw error; // rethrow other unexpected errors
        }
    }

    return response;
}

async function is_401(response: Response): Promise<boolean> {
    if (response.status === 401) {
        clear_session_data();
        await replace("/login");
        return true;
    }
    return false;
}