const { apiClientBaseURL } = require("../config-client")

/**
 * convert object to string
 * @param {any} obj object
 * @returns {string} string
 */
function obj2str(obj) {
    if (Array.isArray(obj)) {
        return JSON.stringify(
            obj.map(function (idx) {
                return obj2str(idx)
            })
        )
    } else if (typeof obj === "object" && obj !== null) {
        var elements = Object.keys(obj)
            .sort()
            .map(function (key) {
                var val = obj2str(obj[key])
                if (val) {
                    return key + ":" + val
                }
            })

        var elementsCleaned = []
        for (var i = 0; i < elements.length; i++) {
            if (elements[i]) elementsCleaned.push(elements[i])
        }

        return "{" + elementsCleaned.join("|") + "}"
    }

    if (obj) return obj
}

/**
 * api request via client or server
 * server function ssrRequest is called via context.ssrRequest, binded in ssr hook
 *
 * @param {string} endpoint
 * @param {ApiOptions} options
 * @param {any} body
 * @param {import("../../../frontend/src/sentry")} sentry
 * @param {typeof fetch} _fetch
 * @returns {Promise<ApiResult<any>>}
 */
function apiRequest(endpoint, options, body, sentry, _fetch) {
    // TODO cache only for GET

    // first check cache if on client
    const cacheKey = obj2str({ endpoint: endpoint, options: options })
    console.log("SSR CHECK", cacheKey)

    let method = options?.method || "GET"

    // @ts-ignore
    if (typeof window !== "undefined" && window.__SSR_CACHE__ && method === "GET") {
        // @ts-ignore
        const cache = window.__SSR_CACHE__[cacheKey]
        console.log("SSR HIT:", cacheKey, cache)
        if (cache) {
            return Promise.resolve(cache)
        }
    }

    let query = "&count=1"
    if (options?.filter) query += "&filter=" + encodeURIComponent(JSON.stringify(options.filter))
    if (options?.sort) query += "&sort=" + options.sort + "&sort=_id"
    if (options?.limit) query += "&limit=" + options.limit
    if (options?.offset) query += "&offset=" + options.offset
    if (options?.projection) query += "&projection=" + options.projection
    if (options?.lookup) query += "&lookup=" + options.lookup

    if (options?.params) {
        Object.keys(options.params).forEach((p) => {
            query += "&" + p + "=" + encodeURIComponent(options.params[p])
        })
    }

    /** @type {{[key: string]: string}} */
    let headers = {
        "Content-Type": "application/json",
    }

    if (options?.headers) headers = { ...headers, ...options.headers }

    if (typeof window === "undefined" && method === "GET") {
        // server

        // reference via context from get hook to tree shake in client
        // @ts-ignore
        const d = context.ssrRequest(cacheKey, endpoint, query, Object.assign({}, options, { method, headers }))
        return d
    } else {
        // client
        let url = apiClientBaseURL + endpoint + (query ? "?" + query : "")

        const span = sentry.currentTransaction()?.startChild({
            op: "fetch",
            description: method + " " + url,
            data: Object.assign({}, options, { url }),
        })
        const trace_id = span?.toTraceparent()
        if (trace_id) {
            headers["sentry-trace"] = trace_id
        }

        /** @type {{[key: string]: any}} */
        const requestOptions = {
            method,
            mode: "cors",
            headers,
        }

        if (method === "POST" || method === "PUT") {
            requestOptions.body = JSON.stringify(body)
        }

        const response = _fetch(url, requestOptions).then((response) => {
            return response?.json().then((json) => {
                if (response?.status < 200 || response?.status >= 400) {
                    return Promise.reject({ response, data: json })
                }
                return Promise.resolve({ data: json || null, count: response.headers?.get("x-results-count") || 0 })
            })
        })

        span?.end()

        // @ts-ignore
        return response
    }
}

module.exports = {
    obj2str,
    apiRequest,
}