// Copyright 2024, Command Line Inc.
// SPDX-License-Identifier: Apache-2.0

import { LayoutTreeActionType, LayoutTreeInsertNodeAction, newLayoutNode } from "@/faraday/index";
import { getLayoutStateAtomForTab } from "@/faraday/lib/layoutAtom";
import { layoutTreeStateReducer } from "@/faraday/lib/layoutState";

import * as jotai from "jotai";
import * as rxjs from "rxjs";
import * as services from "./services";
import * as WOS from "./wos";
import { WSControl } from "./ws";

// TODO remove the window dependency completely
//   we should have the initialization be more orderly -- proceed directly from wave.ts instead of on its own.
const globalStore = jotai.createStore();
let globalWindowId: string = null;
let globalClientId: string = null;
if (typeof window !== "undefined") {
    // this if statement allows us to use the code in nodejs as well
    const urlParams = new URLSearchParams(window.location.search);
    globalWindowId = urlParams.get("windowid") || "74eba2d0-22fc-4221-82ad-d028dd496342";
    globalClientId = urlParams.get("clientid") || "f4bc1713-a364-41b3-a5c4-b000ba10d622";
}
const windowIdAtom = jotai.atom(null) as jotai.PrimitiveAtom<string>;
const clientIdAtom = jotai.atom(null) as jotai.PrimitiveAtom<string>;
globalStore.set(windowIdAtom, globalWindowId);
globalStore.set(clientIdAtom, globalClientId);
const uiContextAtom = jotai.atom((get) => {
    const windowData = get(windowDataAtom);
    const uiContext: UIContext = {
        windowid: get(atoms.windowId),
        activetabid: windowData?.activetabid,
    };
    return uiContext;
}) as jotai.Atom<UIContext>;
const clientAtom: jotai.Atom<Client> = jotai.atom((get) => {
    const clientId = get(clientIdAtom);
    if (clientId == null) {
        return null;
    }
    return WOS.getObjectValue(WOS.makeORef("client", clientId), get);
});
const windowDataAtom: jotai.Atom<WaveWindow> = jotai.atom((get) => {
    const windowId = get(windowIdAtom);
    if (windowId == null) {
        return null;
    }
    const rtn = WOS.getObjectValue<WaveWindow>(WOS.makeORef("window", windowId), get);
    return rtn;
});
const workspaceAtom: jotai.Atom<Workspace> = jotai.atom((get) => {
    const windowData = get(windowDataAtom);
    if (windowData == null) {
        return null;
    }
    return WOS.getObjectValue(WOS.makeORef("workspace", windowData.workspaceid), get);
});
const tabAtom: jotai.Atom<Tab> = jotai.atom((get) => {
    const windowData = get(windowDataAtom);
    if (windowData == null) {
        return null;
    }
    return WOS.getObjectValue(WOS.makeORef("tab", windowData.activetabid), get);
});

const atoms = {
    // initialized in wave.ts (will not be null inside of application)
    windowId: windowIdAtom,
    clientId: clientIdAtom,
    uiContext: uiContextAtom,
    client: clientAtom,
    waveWindow: windowDataAtom,
    workspace: workspaceAtom,
    tabAtom: tabAtom,
};

// key is "eventType" or "eventType|oref"
const eventSubjects = new Map<string, SubjectWithRef<WSEventType>>();
const fileSubjects = new Map<string, SubjectWithRef<WSFileEventData>>();

function getSubjectInternal(subjectKey: string): SubjectWithRef<WSEventType> {
    let subject = eventSubjects.get(subjectKey);
    if (subject == null) {
        subject = new rxjs.Subject<any>() as any;
        subject.refCount = 0;
        subject.release = () => {
            subject.refCount--;
            if (subject.refCount === 0) {
                subject.complete();
                eventSubjects.delete(subjectKey);
            }
        };
        eventSubjects.set(subjectKey, subject);
    }
    subject.refCount++;
    return subject;
}

function getEventSubject(eventType: string): SubjectWithRef<WSEventType> {
    return getSubjectInternal(eventType);
}

function getEventORefSubject(eventType: string, oref: string): SubjectWithRef<WSEventType> {
    return getSubjectInternal(eventType + "|" + oref);
}

function getFileSubject(zoneId: string, fileName: string): SubjectWithRef<WSFileEventData> {
    const subjectKey = zoneId + "|" + fileName;
    let subject = fileSubjects.get(subjectKey);
    if (subject == null) {
        subject = new rxjs.Subject<any>() as any;
        subject.refCount = 0;
        subject.release = () => {
            subject.refCount--;
            if (subject.refCount === 0) {
                subject.complete();
                fileSubjects.delete(subjectKey);
            }
        };
        fileSubjects.set(subjectKey, subject);
    }
    subject.refCount++;
    return subject;
}

const blockCache = new Map<string, Map<string, any>>();

function useBlockCache<T>(blockId: string, name: string, makeFn: () => T): T {
    let blockMap = blockCache.get(blockId);
    if (blockMap == null) {
        blockMap = new Map<string, any>();
        blockCache.set(blockId, blockMap);
    }
    let value = blockMap.get(name);
    if (value == null) {
        value = makeFn();
        blockMap.set(name, value);
    }
    return value as T;
}

const blockAtomCache = new Map<string, Map<string, jotai.Atom<any>>>();

function useBlockAtom<T>(blockId: string, name: string, makeFn: () => jotai.Atom<T>): jotai.Atom<T> {
    let blockCache = blockAtomCache.get(blockId);
    if (blockCache == null) {
        blockCache = new Map<string, jotai.Atom<any>>();
        blockAtomCache.set(blockId, blockCache);
    }
    let atom = blockCache.get(name);
    if (atom == null) {
        atom = makeFn();
        blockCache.set(name, atom);
        console.log("New BlockAtom", blockId, name);
    }
    return atom as jotai.Atom<T>;
}

function getBackendHostPort(): string {
    // TODO deal with dev/production
    return "http://127.0.0.1:8190";
}

function getBackendWSHostPort(): string {
    return "ws://127.0.0.1:8191";
}

let globalWS: WSControl = null;

function handleWSEventMessage(msg: WSEventType) {
    if (msg.eventtype == null) {
        console.log("unsupported event", msg);
        return;
    }
    if (msg.eventtype == "blockfile") {
        const fileData: WSFileEventData = msg.data;
        const fileSubject = getFileSubject(fileData.zoneid, fileData.filename);
        if (fileSubject != null) {
            fileSubject.next(fileData);
        }
        return;
    }

    // we send to two subjects just eventType and eventType|oref
    // we don't use getORefSubject here because we don't want to create a new subject
    const eventSubject = eventSubjects.get(msg.eventtype);
    if (eventSubject != null) {
        eventSubject.next(msg);
    }
    const eventOrefSubject = eventSubjects.get(msg.eventtype + "|" + msg.oref);
    if (eventOrefSubject != null) {
        eventOrefSubject.next(msg);
    }
}

function handleWSMessage(msg: any) {
    if (msg == null) {
        return;
    }
    if (msg.eventtype != null) {
        handleWSEventMessage(msg);
    }
}

function initWS() {
    globalWS = new WSControl(getBackendWSHostPort(), globalStore, globalWindowId, "", (msg) => {
        handleWSMessage(msg);
    });
    globalWS.connectNow("initWS");
}

function sendWSCommand(command: WSCommandType) {
    globalWS.pushMessage(command);
}

// more code that could be moved into an init
// here we want to set up a "waveobj:update" handler
const waveobjUpdateSubject = getEventSubject("waveobj:update");
waveobjUpdateSubject.subscribe((msg: WSEventType) => {
    const update: WaveObjUpdate = msg.data;
    WOS.updateWaveObject(update);
});

/**
 * Get the preload api.
 */
function getApi(): ElectronApi {
    return (window as any).api;
}

async function createBlock(blockDef: BlockDef) {
    const rtOpts: RuntimeOpts = { termsize: { rows: 25, cols: 80 } };
    const blockId = await services.ObjectService.CreateBlock(blockDef, rtOpts);
    const insertNodeAction: LayoutTreeInsertNodeAction<TabLayoutData> = {
        type: LayoutTreeActionType.InsertNode,
        node: newLayoutNode<TabLayoutData>(undefined, undefined, undefined, { blockId }),
    };
    const activeTabId = globalStore.get(atoms.uiContext).activetabid;
    const layoutStateAtom = getLayoutStateAtomForTab(
        activeTabId,
        WOS.getWaveObjectAtom<Tab>(WOS.makeORef("tab", activeTabId))
    );
    const curState = globalStore.get(layoutStateAtom);
    globalStore.set(layoutStateAtom, layoutTreeStateReducer(curState, insertNodeAction));
}

// when file is not found, returns {data: null, fileInfo: null}
async function fetchWaveFile(
    zoneId: string,
    fileName: string,
    offset?: number
): Promise<{ data: Uint8Array; fileInfo: WaveFile }> {
    let usp = new URLSearchParams();
    usp.set("zoneid", zoneId);
    usp.set("name", fileName);
    if (offset != null) {
        usp.set("offset", offset.toString());
    }
    const resp = await fetch(getBackendHostPort() + "/wave/file?" + usp.toString());
    if (!resp.ok) {
        if (resp.status === 404) {
            return { data: null, fileInfo: null };
        }
        throw new Error("error getting wave file: " + resp.statusText);
    }
    if (resp.status == 204) {
        return { data: null, fileInfo: null };
    }
    let fileInfo64 = resp.headers.get("X-ZoneFileInfo");
    if (fileInfo64 == null) {
        throw new Error(`missing zone file info for ${zoneId}:${fileName}`);
    }
    let fileInfo = JSON.parse(atob(fileInfo64));
    const data = await resp.arrayBuffer();
    return { data: new Uint8Array(data), fileInfo };
}

export {
    WOS,
    atoms,
    createBlock,
    fetchWaveFile,
    getApi,
    getBackendHostPort,
    getEventORefSubject,
    getEventSubject,
    getFileSubject,
    globalStore,
    globalWS,
    initWS,
    sendWSCommand,
    useBlockAtom,
    useBlockCache,
};