import cp from "child_process";
import express from "express";
import chalk from "chalk";
import path from "path";
import md5 from "md5";
import fs from "fs";
import os from "os";
import {
    fileURLToPath
} from "node:url";
import {
    dirname
} from "node:path";
import crypto from "crypto";

const __filename = fileURLToPath(import.meta.url);
const __dirname = dirname(__filename);

const app = express();

const DIR = process.env.NODE_ENV === "development" ? path.join(__dirname, "../") : path.join(os.homedir(), ".ncicd");

if (process.env.NODE_ENV !== "development" && !fs.existsSync(DIR)) {
    fs.mkdirSync(DIR, {
        recursive: true
    });
}

app.get("/", async (req, res) => {
    const password = req.query.password;
    const name = req.query.name;

    if (!name) {
        res.status(400).send("Access denied.");
        return;
    }

    console.log(
        chalk.cyan(`${name} - Pipeline is running`)
    );

    const file = fs.readFileSync(path.join(DIR, "ncicd.conf")).toString();
    const json = JSON.parse(file);

    const currentData = json.find(item => item.name === name);

    if (!currentData) {
        console.error(chalk.red(`Error: No configuration found for pipeline '${name}'`));
        res.status(400).send(`Error: Pipeline '${name}' not found`);
        return;
    }

    const pass = password as string;

    let unencryptedKey = currentData.rsaKeys.privateKey;
    try {
        const privateKeyObj = crypto.createPrivateKey({
            key: currentData.rsaKeys.privateKey,
            format: "pem",
            passphrase: pass
        });
        unencryptedKey = privateKeyObj.export({
            type: "pkcs1",
            format: "pem"
        });
    } catch (e) {
        console.error(chalk.yellow("Note: Could not decrypt private key. It might already be unencrypted or the password is wrong."));
    }

    const uniqueKeyFile = path.join(DIR, `privateKey_${name}_${Date.now()}.pem`);
    fs.writeFileSync(uniqueKeyFile, unencryptedKey, {
        mode: "600"
    });
    fs.chmodSync(uniqueKeyFile, "0600");

    try {
        await new Promise<void>((resolve, reject) => {
            const gitPuller = cp.exec(`cd ${path.join(currentData.targetPath, currentData.name)} && GIT_SSH_COMMAND="ssh -o StrictHostKeyChecking=no -i ${uniqueKeyFile}" git fetch origin ${currentData.branch} && git reset --hard FETCH_HEAD`, {
                maxBuffer: 1024 * 1024 * 500
            }, (error, stdout, stderr) => {
                if (error) {
                    console.error(chalk.red(`Git pull failed for ${name}:`), error);
                    reject(error);
                } else {
                    console.log(chalk.green(`Git pull successful for ${name}:`), stdout);
                    resolve();
                }
            });

            gitPuller.stdout?.on("data", (data) => {
                const output = data.toString();
                console.log(chalk.gray(`[git stdout]: ${output}`));
            });

            gitPuller.stderr?.on("data", (data) => {
                const output = data.toString();
                console.log(chalk.gray(`[git stderr]: ${output}`));
                if (output.toLowerCase().includes("passphrase")) {
                    console.error(chalk.red("Incorrect password provided, SSH key could not be decrypted."));
                    gitPuller.kill();
                }
            });
        });
    } catch (err) {
        res.status(500).send(`Failed to pull repository for ${name}`);
        return;
    } finally {
        if (fs.existsSync(uniqueKeyFile)) {
            fs.unlinkSync(uniqueKeyFile);
        }
    }

    const directory = path.join(currentData.targetPath, currentData.name);

    if (currentData.nodeVersion) {
        cp.execSync(`export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \\. "$NVM_DIR/nvm.sh" && nvm install ${currentData.nodeVersion} && nvm use ${currentData.nodeVersion} && npm i -g yarn pm2 && cd ${directory} && yarn install --check-files --ignore-engines && yarn ${currentData.buildCommand ? currentData.buildCommand : "build"}`, {
            maxBuffer: 1024 * 1024 * 50,
            stdio: "inherit"
        });
    } else {
        cp.execSync(`cd ${directory} && yarn install --ignore-engines && yarn ${currentData.buildCommand ? currentData.buildCommand : "build"}`, {
            maxBuffer: 1024 * 1024 * 20,
            stdio: "inherit"
        });
    }

    let pm2RestartCommand = `npx pm2 restart ${currentData.name} --update-env`;
    let pm2StartCommand = `cd ${directory} && npx pm2 start yarn --name ${currentData.name} --time --log-date-format "YYYY-MM-DDTHH:mm:ss.SSSZ" -l ${currentData.name}-combined.log -- ${currentData.command ? currentData.command : "start:prod"}`;

    if (currentData.nodeVersion) {
        pm2RestartCommand = `export NVM_DIR="$HOME/.nvm"\n[ -s "$NVM_DIR/nvm.sh" ] && \\. "$NVM_DIR/nvm.sh" && nvm use ${currentData.nodeVersion} && ${pm2RestartCommand}`;
        pm2StartCommand = `export NVM_DIR="$HOME/.nvm"\n[ -s "$NVM_DIR/nvm.sh" ] && \\. "$NVM_DIR/nvm.sh" && nvm use ${currentData.nodeVersion} && ${pm2StartCommand}`;
    }

    try {
        cp.execSync(pm2RestartCommand);
    } catch {
        cp.execSync(pm2StartCommand);
    }

    if (process.platform !== "win32") {
        cp.execSync("pm2 startup");
    }

    cp.execSync("pm2 save");

    console.log(
        chalk.green(`${name} - Pipeline is completed successfully`)
    );

    res.send(`${name} - OK`);
    return;
});

app.post("/", async (req, res) => {
    const password = req.query.password;
    const name = req.query.name;

    if (!name) {
        res.status(403).send("Access denied.");
        return;
    }

    console.log(
        chalk.cyan(`${name} - Pipeline is running`)
    );

    const file = fs.readFileSync(path.join(DIR, "ncicd.conf")).toString();
    const json = JSON.parse(file);

    const currentData = json.find(item => item.name === name);

    if (!currentData) {
        console.error(chalk.red(`Error: No configuration found for pipeline '${name}'`));
        res.status(400).send(`Error: Pipeline '${name}' not found`);
        return;
    }

    const pass = password as string;

    let unencryptedKey = currentData.rsaKeys.privateKey;
    try {
        const privateKeyObj = crypto.createPrivateKey({
            key: currentData.rsaKeys.privateKey,
            format: "pem",
            passphrase: pass
        });
        unencryptedKey = privateKeyObj.export({
            type: "pkcs1",
            format: "pem"
        });
    } catch (e) {
        console.error(chalk.yellow("Note: Could not decrypt private key. It might already be unencrypted or the password is wrong."));
    }

    const uniqueKeyFile = path.join(DIR, `privateKey_${name}_${Date.now()}.pem`);
    fs.writeFileSync(uniqueKeyFile, unencryptedKey, {
        mode: "600"
    });
    fs.chmodSync(uniqueKeyFile, "0600");

    try {
        await new Promise<void>((resolve, reject) => {
            const gitPuller = cp.exec(`cd ${path.join(currentData.targetPath, currentData.name)} && GIT_SSH_COMMAND="ssh -o StrictHostKeyChecking=no -i ${uniqueKeyFile}" git fetch origin ${currentData.branch} && git reset --hard FETCH_HEAD`, {
                maxBuffer: 1024 * 1024 * 500
            }, (error, stdout, stderr) => {
                if (error) {
                    console.error(chalk.red(`Git pull failed for ${name}:`), error);
                    reject(error);
                } else {
                    console.log(chalk.green(`Git pull successful for ${name}:`), stdout);
                    resolve();
                }
            });

            gitPuller.stdout?.on("data", (data) => {
                const output = data.toString();
                console.log(chalk.gray(`[git stdout]: ${output}`));
            });

            gitPuller.stderr?.on("data", (data) => {
                const output = data.toString();
                console.log(chalk.gray(`[git stderr]: ${output}`));
                if (output.toLowerCase().includes("passphrase")) {
                    console.error(chalk.red("Incorrect password provided, SSH key could not be decrypted."));
                    gitPuller.kill();
                }
            });
        });
    } catch (err) {
        res.status(500).send(`Failed to pull repository for ${name}`);
        return;
    } finally {
        if (fs.existsSync(uniqueKeyFile)) {
            fs.unlinkSync(uniqueKeyFile);
        }
    }

    const directory = path.join(currentData.targetPath, currentData.name);

    if (currentData.nodeVersion) {
        cp.execSync(`export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \\. "$NVM_DIR/nvm.sh" && nvm install ${currentData.nodeVersion} && nvm use ${currentData.nodeVersion} && npm i -g yarn pm2 && cd ${directory} && yarn install --check-files --ignore-engines && yarn ${currentData.buildCommand ? currentData.buildCommand : "build"}`, {
            maxBuffer: 1024 * 1024 * 50,
            stdio: "inherit"
        });
    } else {
        cp.execSync(`cd ${directory} && yarn && yarn ${currentData.buildCommand ? currentData.buildCommand : "build"}`, {
            maxBuffer: 1024 * 1024 * 20,
            stdio: "inherit"
        });
    }

    let pm2RestartCommand2 = `npx pm2 restart ${currentData.name} --update-env`;
    let pm2StartCommand2 = `cd ${directory} && npx pm2 start yarn --name ${currentData.name} --time --log-date-format "YYYY-MM-DDTHH:mm:ss.SSSZ" -l ${currentData.name}-combined.log -- ${currentData.command ? currentData.command : "start:prod"}`;

    if (currentData.nodeVersion) {
        pm2RestartCommand2 = `export NVM_DIR="$HOME/.nvm"\n[ -s "$NVM_DIR/nvm.sh" ] && \\. "$NVM_DIR/nvm.sh" && nvm use ${currentData.nodeVersion} && ${pm2RestartCommand2}`;
        pm2StartCommand2 = `export NVM_DIR="$HOME/.nvm"\n[ -s "$NVM_DIR/nvm.sh" ] && \\. "$NVM_DIR/nvm.sh" && nvm use ${currentData.nodeVersion} && ${pm2StartCommand2}`;
    }

    try {
        cp.execSync(pm2RestartCommand2);
    } catch {
        cp.execSync(pm2StartCommand2);
    }

    if (process.platform !== "win32") {
        cp.execSync("pm2 startup");
    }

    cp.execSync("pm2 save");

    console.log(
        chalk.green(`${name} - Pipeline is completed successfully`)
    );

    res.send(`${name} - OK`);
    return;
});

const ncicdJSON = JSON.parse(fs.readFileSync(path.join(DIR, "ncicd.conf.json")).toString());

app.listen(ncicdJSON.PORT, ncicdJSON.bind, () => {
    console.log("System working on", ncicdJSON.bind, ":", ncicdJSON.PORT);
});