// ==UserScript==
// @name         cph-submit.frontend
// @namespace    http://tampermonkey.net/
// @version      0.1.0
// @description  cph-submit 前台脚本
// @author       Andy_hpy
// @match        https://codeforces.com/problemset/submit*
// @match        https://codeforces.com/contest/*/submit*
// @grant        GM_getValue
// @grant        GM_setValue
// @grant        GM_deleteValue
// @grant        GM_addValueChangeListener
// @run-at       document-idle
// @storageName  cph-submit
// ==/UserScript==

// ---------- 工具函数 ----------
function isContestProblem(problemUrl) {
    return problemUrl && problemUrl.includes('contest');
}

function getExpectedSubmitUrl(problemUrl) {
    if (!problemUrl) return null;
    if (!isContestProblem(problemUrl)) {
        return 'https://codeforces.com/problemset/submit';
    }
    const match = problemUrl.match(/contest\/(\d+)/);
    if (match) {
        return `https://codeforces.com/contest/${match[1]}/submit`;
    }
    return null;
}

function isCorrectPage(task) {
    if (!task || !task.url) return false;
    const expected = getExpectedSubmitUrl(task.url);
    return expected && window.location.href.startsWith(expected);
}

function waitForElement(selector, timeout = 5000) {
    return new Promise((resolve, reject) => {
        const start = Date.now();
        const check = () => {
            const el = document.querySelector(selector);
            if (el) resolve(el);
            else if (Date.now() - start > timeout) reject(new Error(`元素 ${selector} 未找到`));
            else setTimeout(check, 200);
        };
        check();
    });
}

// 等待cloudflare验证组件
async function waitForCaptchaIfNeeded(timeout = 60000) {
    const captchaInput = document.querySelector('input[id^="cf-chl-widget-"][id$="_response"]');
    captchaInput.focus(); // 如果需要点击，可以直接按 Enter
    const startTime = Date.now();
    while (Date.now() - startTime < timeout) {
        if (captchaInput.value.trim() !== '') {
            return true;
        }
        await new Promise(resolve => setTimeout(resolve, 500));
    }
    return false;
}


async function fillAndSubmit(task) {
    try {
        const langEl = await waitForElement('select[name="programTypeId"]');
        const codeEl = await waitForElement('#sourceCodeTextarea');

        let problemEl;
        if (isContestProblem(task.url)) {
            problemEl = await waitForElement('select[name="submittedProblemIndex"]');
        } else {
            problemEl = await waitForElement('input[name="submittedProblemCode"]');
        }

        langEl.value = task.languageId;
        langEl.dispatchEvent(new Event('change', { bubbles: true }));
        langEl.dispatchEvent(new Event('blur', { bubbles: true }));

        codeEl.value = task.sourceCode;
        codeEl.dispatchEvent(new Event('input', { bubbles: true }));
        codeEl.dispatchEvent(new Event('blur', { bubbles: true }));

        if (isContestProblem(task.url)) {
            const problemLetter = task.url.split('/problem/')[1];
            problemEl.value = problemLetter;
        } else {
            problemEl.value = task.problemName;
        }
        problemEl.dispatchEvent(new Event('change', { bubbles: true }));
        problemEl.dispatchEvent(new Event('blur', { bubbles: true }));

        const shouldSubmit = await waitForCaptchaIfNeeded(60000);
        if (!shouldSubmit) {
            alert('cloudflare验证组件超时，请手动提交');
            GM_deleteValue('pendingSubmit');
            return;
        }

        const submitBtnOrForm = document.querySelector("#singlePageSubmitButton");
        if (submitBtnOrForm) {
            submitBtnOrForm.click();
        }

        GM_deleteValue('pendingSubmit');
    } catch (err) {
        console.error('自动填充失败', err);
    }
}

GM_addValueChangeListener("pendingSubmit", (name, oldValue, newValue, remote) => {
    if (newValue) {
        try {
            const task = JSON.parse(newValue);
            if (isCorrectPage(task)) {
                fillAndSubmit(task);
            }
        } catch (e) {
            console.error('解析任务失败', e);
        }
    }
});

const taskJson = GM_getValue('pendingSubmit');
if (taskJson) {
    try {
        const task = JSON.parse(taskJson);
        if (Date.now() - task.timestamp > 60000) {
            GM_deleteValue('pendingSubmit');
        } else if (isCorrectPage(task)) {
            fillAndSubmit(task);
        }
    } catch (e) {
        console.error('解析任务失败', e);
    }
}