// React4xp static-asset file server, with specified cache control headers

const ioLib = require('/lib/xp/io');
const cacheLib = require('/lib/cache');
const { getReact4xpEntry, getReact4xpHashedChunk } = require('/lib/enonic/react4xp/clientCacheResources');
const { getSuffix } = require('/lib/enonic/react4xp/serviceRoots');

// react4xp_constants.json is not part of lib-react4xp-runtime,
// it's an external shared-constants file expected to exist in the react4xp lib build directory.
// Easiest: the NPM package react4xp-buildconstants creates this file and copies it here.
const {
    R4X_TARGETSUBDIR, ENTRIES_FILENAME
} = require('/lib/enonic/react4xp/react4xp_constants.json');

const REACT4XP_ROOT = `/${R4X_TARGETSUBDIR}/`;

const componentsCache = cacheLib.newCache({
    size: 100,
    expire: 108000 // 30 hours
});


const ENTRIES = JSON.parse(
    ioLib.readLines(
        ioLib.getResource(REACT4XP_ROOT + ENTRIES_FILENAME).getStream()
    ).join(" ")
).map(entry => `${entry}.js`);



// Handle all GET requests
exports.get = function (req) {
    //log.info("/react4xp/ service: GET req (" + typeof req + "): " + JSON.stringify(req, null, 2));
    try {
        let target = getSuffix(req.path, 'react4xp').trim();
        //log.info("React4xp service target asset: " + JSON.stringify(target, null, 2));

        if (!target) {
            throw Error(`Missing target asset in URL ('${req.path}')`);
        }

        let resource = ioLib.getResource(REACT4XP_ROOT + target);
        if (!resource || !resource.exists()) {
            resource = ioLib.getResource(REACT4XP_ROOT + target + '.js');

            if (!resource || !resource.exists()) {
                log.warning(`STATUS 404: file not found: ${REACT4XP_ROOT + target}`);
                return {
                    status: 404,
                    body: `File not found: ${target}`,
                    contentType: 'text/plain'
                }

            } else {
                target += ".js";
            }
        }

        if (ENTRIES.indexOf(target) === -1) {
            return componentsCache.get(target, function() {
                //log.info("Caching React4XP component: " + target);
                return getReact4xpHashedChunk(resource);
            });

        } else {
            return componentsCache.get(target, function() {
                //log.info("Caching React4XP entry: " + target);
                return getReact4xpEntry(resource);
            });
        }

    } catch (e) {
        log.warning(`STATUS 400: ${e.message}`);
        return {
            status: 400,
            body: e.message,
            contentType: 'text/plain'
        }
    }
};