"use strict";
var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
    if (k2 === undefined) k2 = k;
    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
}) : (function(o, m, k, k2) {
    if (k2 === undefined) k2 = k;
    o[k2] = m[k];
}));
var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
    Object.defineProperty(o, "default", { enumerable: true, value: v });
}) : function(o, v) {
    o["default"] = v;
});
var __importStar = (this && this.__importStar) || function (mod) {
    if (mod && mod.__esModule) return mod;
    var result = {};
    if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
    __setModuleDefault(result, mod);
    return result;
};
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
    return new (P || (P = Promise))(function (resolve, reject) {
        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
        step((generator = generator.apply(thisArg, _arguments || [])).next());
    });
};
var __importDefault = (this && this.__importDefault) || function (mod) {
    return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
const fs_1 = __importDefault(require("fs"));
const events_1 = require("events");
const sha1_1 = __importDefault(require("sha1"));
const diff = __importStar(require("diff"));
const asyncCall_1 = __importDefault(require("./asyncCall"));
class FileProxy extends events_1.EventEmitter {
    constructor(filePath) {
        super();
        this.alive = true;
        this.filePath = filePath;
        //console.log("File proxy created:", filePath);
        if (!fs_1.default.existsSync(filePath))
            throw new Error(`file not exist: ${filePath}`);
        asyncCall_1.default(fs_1.default.stat, filePath)
            .then(stats => {
            this.diskTimestamp = stats.mtime.getTime();
            this.timestamp = this.diskTimestamp;
            return asyncCall_1.default(fs_1.default.readFile, filePath);
        })
            .then(buffer => {
            this.content = buffer.toString();
            this.fullSync();
        });
        this.fileListener = (current) => __awaiter(this, void 0, void 0, function* () {
            this.diskTimestamp = current.mtime.getTime();
            this.timestamp = this.diskTimestamp;
            const buffer = yield asyncCall_1.default(fs_1.default.readFile, filePath);
            if (!buffer) {
                this.emit("error", { description: "file reading failed" });
                return;
            }
            const newContent = buffer.toString();
            const newHash = sha1_1.default(newContent);
            if (newHash !== this.hash) {
                const patch = diff.createPatch(filePath, this.content, newContent);
                this.emit("increase", {
                    timestamp: this.timestamp,
                    fromHash: this.hash,
                    toHash: newHash,
                    patch,
                });
                this.content = newContent;
            }
        });
        fs_1.default.watchFile(filePath, this.fileListener);
        this.keepWriteFile();
    }
    dispose() {
        this.alive = false;
        if (this.fileListener)
            fs_1.default.unwatchFile(this.filePath, this.fileListener);
    }
    makeWritePromise() {
        return new Promise(resolve => this.writeFile = resolve);
    }
    keepWriteFile() {
        return __awaiter(this, void 0, void 0, function* () {
            let writeSignal = this.makeWritePromise();
            while (this.alive) {
                yield writeSignal;
                writeSignal = this.makeWritePromise();
                //console.debug("keepWriteFile:", this.timestamp, this.diskTimestamp);
                if (this.timestamp > this.diskTimestamp) {
                    yield asyncCall_1.default(fs_1.default.writeFile, this.filePath, this.content);
                }
            }
        });
    }
    get hash() {
        return sha1_1.default(this.content);
    }
    fullSync() {
        this.emit("fullSync", {
            timestamp: this.timestamp,
            content: this.content,
            hash: this.hash,
        });
    }
    increase({ timestamp, fromHash, toHash, patch }) {
        if (this.hash !== fromHash) {
            if (this.timestamp > timestamp)
                // web content is out of date
                this.fullSync();
            else
                console.warn("[FileProxy] disk file content is behind increase base:", this.timestamp, timestamp);
        }
        else {
            this.content = diff.applyPatch(this.content, patch);
            this.timestamp = timestamp;
            console.assert(this.hash === toHash, "[FileProxy] verify failed:", this.hash, toHash, this.content);
            // trigger file writing
            this.writeFile();
        }
    }
}
exports.default = FileProxy;
;