const axios = require('axios');
const fs = require('fs');
const path = require('path');
const FormData = require('form-data');

class ILoveImgRemoveBG {
    BASE_URL = 'https://www.iloveimg.com';

    constructor() {
        this.token = null;
        this.taskId = null;
        this.workerServer = null;
        this.apiVersion = 'v1';
    }

    async getInitialConfig() {
        console.log('[*] Fetching initial config...');

        const resp = await axios.get(
            'https://www.iloveimg.com/remove-background',
            {
                headers: {
                    'User-Agent':
                        'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36',
                    Accept:
                        'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8'
                }
            }
        );

        const html = resp.data;

        const tokenMatch = html.match(/"token":"([^"]+)"/);

        if (tokenMatch) {
            this.token = tokenMatch[1];
            console.log(
                `[+] Token found: ${this.token.substring(0, 50)}...`
            );
        }

        const taskMatch = html.match(
            /ilovepdfConfig\.taskId\s*=\s*'([^']+)'/
        );

        if (taskMatch) {
            this.taskId = taskMatch[1];
            console.log(
                `[+] Task ID found: ${this.taskId.substring(0, 30)}...`
            );
        }

        const serversMatch = html.match(/"servers":\s*\[([^\]]+)\]/);

        if (serversMatch) {
            const servers = JSON.parse('[' + serversMatch[1] + ']');
            this.workerServer = `https://${servers[0]}.iloveimg.com`;

            console.log(`[+] Worker server: ${this.workerServer}`);
        }

        if (!this.token || !this.taskId || !this.workerServer) {
            throw new Error('Failed to extract config from page');
        }

        return true;
    }

    async uploadFile(filePath) {
        console.log(`[*] Uploading ${filePath}...`);

        const form = new FormData();

        form.append('task', this.taskId);
        form.append('v', '2.5.0');
        form.append('preview', '1');

        form.append(
            'file',
            fs.createReadStream(filePath),
            path.basename(filePath)
        );

        const resp = await axios.post(
            `${this.workerServer}/${this.apiVersion}/upload`,
            form,
            {
                headers: {
                    Authorization: `Bearer ${this.token}`,
                    ...form.getHeaders()
                },
                maxBodyLength: Infinity,
                validateStatus: () => true
            }
        );

        if (resp.status !== 200) {
            throw new Error(
                `Upload failed: ${resp.status} - ${JSON.stringify(resp.data)}`
            );
        }

        console.log(
            `[+] Upload success: ${JSON.stringify(resp.data).substring(
                0,
                100
            )}`
        );

        return resp.data.server_filename;
    }

    async removeBackground(serverFilename) {
        console.log('[*] Removing background...');

        const form = new FormData();

        form.append('task', this.taskId);
        form.append('server_filename', serverFilename);

        const resp = await axios.post(
            `${this.workerServer}/${this.apiVersion}/removebackground`,
            form,
            {
                headers: {
                    Authorization: `Bearer ${this.token}`,
                    ...form.getHeaders()
                },
                responseType: 'arraybuffer',
                validateStatus: () => true
            }
        );

        if (resp.status !== 200) {
            throw new Error(`Remove background failed: ${resp.status}`);
        }

        const buffer = Buffer.from(resp.data);

        console.log('[+] Remove background success');

        return buffer;
    }

    async process(inputFile, outputFile = null) {
        if (!outputFile) {
            const ext = path.extname(inputFile);
            const base = path.basename(inputFile, ext);
            outputFile = `${base}_nobg.png`;
        }

        await this.getInitialConfig();

        const serverFilename = await this.uploadFile(inputFile);

        console.log(`[+] Server filename: ${serverFilename}`);

        const result = await this.removeBackground(serverFilename);

        fs.writeFileSync(outputFile, result);

        console.log(`[+] Result saved to: ${outputFile}`);

        return outputFile;
    }
}

async function main() {
    const args = process.argv.slice(2);

    if (args.length < 1) {
        console.log(
            `Usage: node ${path.basename(__filename)} <image_file> [output_file]`
        );

        console.log('');
        console.log('Examples:');
        console.log(`node ${path.basename(__filename)} photo.jpg`);
        console.log(
            `node ${path.basename(__filename)} photo.jpg result.png`
        );

        process.exit(1);
    }

    const inputFile = args[0];
    const outputFile = args[1] || null;

    if (!fs.existsSync(inputFile)) {
        console.error(`Error: File not found: ${inputFile}`);
        process.exit(1);
    }

    const scraper = new ILoveImgRemoveBG();

    try {
        const result = await scraper.process(
            inputFile,
            outputFile
        );

        console.log(`\n[SUCCESS] Output saved to: ${result}`);
    } catch (err) {
        console.error('\n[ERROR]', err.message);

        if (err.response) {
            console.error('Status:', err.response.status);
            console.error('Response:', err.response.data);
        }

        process.exit(1);
    }
}

main();