const fs = require('fs');
const path = require('path');

const systemNames = [
    'uint32', 'uint64', 'int32', 'int64', 'sint32', 'sint64',
    'fixed32', 'fixed64', 'sfixed32', 'sfixed64', 'float', 'double',
    'bool', 'string', 'bytes'
];

const protoFilePath = "deobf.proto";
const outputPath1 = "./unimplemented";
const outputPath2 = "./proto";
const ntPath = '';
const version = `5.0`;

var cmdid_gen = [];

// Read the skip list
const skipFilePath = './skip2.txt';
let skipList;
try {
    const skipFileContent = fs.readFileSync(skipFilePath, 'utf-8');
    skipList = skipFileContent.split('\n').map(line => line.trim()).filter(line => line.length > 0);
} catch (err) {
    console.error('Error reading skip file:', err);
    skipList = [];
}

function splitProtoFile(protoFilePath, nameTranslationPath = null, version = "0.0") {

    let ntMap = {};
    const lines = fs.readFileSync(protoFilePath, 'utf-8').split('\n');

    if (nameTranslationPath) {
        const ntLines = fs.readFileSync(nameTranslationPath, 'utf-8').split('\n');
        for (let ntLine of ntLines) {
            if (ntLine.trim().startsWith('#')) continue;
            const [key, value] = ntLine.trim().split(' -> ');
            ntMap[key] = value;
        }
    }

    let currentContent = [];
    let currentName = null;
    let cmdid = null;

    for (let i = 0; i < lines.length; i++) {
        const line = lines[i].trim();

        if (line.startsWith('// CmdID: ')) {
            cmdid = line;
        } else if (line.startsWith("message") || line.startsWith("enum")) {
            currentName = line.split(' ')[1];
            currentContent.push(lines[i]);
        } else if (line.startsWith("}")) {

            currentContent.push(lines[i]);

            // save
            saveContent(currentName, currentContent, ntMap, cmdid, version);

            if (cmdid) {
                var d = new Object();
                d["name"] = currentName;
                d["id"] = parseInt(cmdid.replace(`// CmdID: `, ""));
                cmdid_gen.push(d)
            }

            // clear
            currentContent = [];
            currentName = null;
            cmdid = null;

        } else if (currentName) {
            currentContent.push(lines[i]);
        }
    }

    save_json(cmdid_gen, `cmdid.json`);

}

function saveContent(name, content, ntMap = {}, cmdid = "", version = "") {
    if (name in ntMap && !/[a-z]/.test(name)) {
        name = ntMap[name];
    }

    const filename = `${name}.proto`;
    const nestedMessages = findNestedMessages(content);

    var isEnum = false
    for (let i = 0; i < content.length; i++) {
        let line = content[i];
        if (isEnum && line.includes("_")) {
            content[i] = renameConstant(line);
        }
        if (line.startsWith('enum')) {
            isEnum = true;
        }
    }

    let contentStr = content.join('\n');
    for (const [key, value] of Object.entries(ntMap)) {
        if (/[a-z]/.test(key)) continue;
        contentStr = contentStr.replace(new RegExp(key, 'g'), value);
    }

    let output = `syntax = "proto3";\n\noption java_package = "emu.grasscutter.net.proto";\n// Version: ${version}\n`;
    if (cmdid) {
        //console.log(cmdid)
        output += `${cmdid}\n`;
    }

    if (nestedMessages.length > 0) {
        const importStatements = nestedMessages.map(nm => `import "${nm}.proto";`).join('\n');
        output += `\n${importStatements}\n\n`;
    } else {
        output += '\n';
    }
    output += contentStr;

    // update file proto
    const filePath2 = path.join(outputPath2, filename);
    const filePath1 = path.join(outputPath1, filename);
    if (fs.existsSync(filePath2)) {

        // skip update if file skip or broke
        if (skipList.includes(filename.replace(".proto", ""))) {
            console.log('Skipping update file:', filePath2);
            // TODO: fix it
        } else {
            console.log(`File exist add to implemented: ${filePath2}`);
            fs.writeFileSync(filePath2, output);
        }

    } else {
        //console.log(`File does not exist add to unimplemented: ${filePath1}`);
        fs.writeFileSync(filePath1, output);
    }

}

function checkForNestedMessages(line) {
    const nestedMessages = new Set();
    if (line.startsWith('map<')) {
        const mapsplit = line.replace('map<', '').replace('>', '').replace(',', '').split(' =')[0].split(' ').slice(0, -1);
        for (const item of mapsplit) {
            if (!systemNames.includes(item)) {
                nestedMessages.add(item);
            }
        }
    } else if (line.startsWith('repeated')) {
        const part1 = line.split(' ')[1];
        if (!systemNames.includes(part1)) {
            nestedMessages.add(part1);
        }
    } else {
        const part1 = line.split(' ')[0];
        if (!systemNames.includes(part1)) {
            nestedMessages.add(part1);
        }
    }
    return nestedMessages;
}

function findNestedMessages(content) {
    const nestedMessages = new Set();
    const messageType = content[0].trim().split(' ')[0];
    if (messageType === 'enum') return nestedMessages;
    for (let line of content) {
        line = line.trim();
        if (line.startsWith('message') || line === '}' || line === '') continue;
        const lineSplit = line.split(' ');
        if (lineSplit[0] === 'oneof') continue;
        const nested = checkForNestedMessages(line);
        nested.forEach(nm => nestedMessages.add(nm));
    }
    return [...nestedMessages];
}

// save json
function save_json(raw, file) {
    var j = JSON.stringify(raw, null, 4);
    save(j, file);
}

function save(raw, file) {
    fs.writeFile(file, raw, "utf8", function (err) {
        if (err) {
            console.log("An error occured while writing to File.");
            return console.log(err);
        }
        console.log("File has been saved: " + file);
    });
}

function renameConstant(declaration) {
    // Split the declaration into the name and value parts
    const [name, value] = declaration.split(" = ");

    // Extract the relevant parts before and after the first underscore
    const [prefix, relevantPart] = name.split("_", 2);

    // Combine the prefix and the relevant part, and then convert to uppercase and replace camelCase with underscores
    const newName = `${prefix}_${relevantPart}`.replace(/([a-z])([A-Z])/g, '$1_$2').toUpperCase();

    // Return the renamed declaration
    return `${newName} = ${value}`;
}

splitProtoFile(protoFilePath, ntPath, version);

console.log("Proto file split successfully!");