// ==UserScript==
// @name         Linux.do 帖子浏览记录
// @namespace    http://tampermonkey.net/
// @version      1.5
// @description  记录最近浏览的10-20个帖子并提供快速访问，支持单条删除记录
// @author       LiNFERS
// @match        https://linux.do/*
// @grant        GM_setValue
// @grant        GM_getValue
// ==/UserScript==

(function () {
    'use strict';

    // 工具函数：设置样式
    function setElementStyle(element, styles) {
        for (const [key, value] of Object.entries(styles)) {
            element.style[key] = value;
        }
    }

    // 创建主按钮
    const btn = document.createElement('button');
    btn.innerHTML = '最近浏览';
    setElementStyle(btn, {
        position: 'fixed',
        bottom: GM_getValue('btnBottom', '20px'),
        right: GM_getValue('btnRight', '20px'),
        zIndex: '9999',
        padding: '10px 20px',
        background: 'rgba(255, 255, 255, 0.6)',
        color: '#333',
        border: 'none',
        borderRadius: '25px',
        cursor: 'pointer',
        backdropFilter: 'blur(5px)',
        boxShadow: '0 2px 10px rgba(0,0,0,0.1)',
        transition: 'all 0.3s ease',
    });
    document.body.appendChild(btn);

    // 创建移动按钮
    const moveBtn = document.createElement('button');
    moveBtn.innerHTML = '↑↓';
    setElementStyle(moveBtn, {
        position: 'fixed',
        bottom: GM_getValue('btnBottom', '20px'),
        right: `${parseInt(GM_getValue('btnRight', '20px')) + btn.offsetWidth + 10}px`,
        zIndex: '9999',
        width: '30px',
        height: '30px',
        background: 'rgba(255, 255, 255, 0.6)',
        color: '#333',
        border: 'none',
        borderRadius: '50%',
        cursor: 'pointer',
        backdropFilter: 'blur(5px)',
        boxShadow: '0 2px 10px rgba(0,0,0,0.1)',
        transition: 'all 0.3s ease',
        fontSize: '16px',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
    });
    document.body.appendChild(moveBtn);

    // 创建弹窗
    const popup = document.createElement('div');
    setElementStyle(popup, {
        display: 'none',
        position: 'fixed',
        bottom: '80px',
        right: '20px',
        width: '300px',
        maxHeight: '400px',
        background: 'rgba(255, 255, 255, 0.95)',
        borderRadius: '15px',
        boxShadow: '0 2px 10px rgba(0,0,0,0.1)',
        zIndex: '9999',
        overflowY: 'auto',
        padding: '10px',
        backdropFilter: 'blur(10px)',
    });
    document.body.appendChild(popup);

    // 移动功能
    let isDragging = false;
    let isMovable = false;
    let startX, startY, initialX, initialY;

    moveBtn.addEventListener('click', () => {
        isMovable = !isMovable;
        moveBtn.style.background = isMovable ? 'rgba(255, 68, 68, 0.9)' : 'rgba(255, 255, 255, 0.6)';
        btn.style.cursor = isMovable ? 'move' : 'pointer';
    });

    btn.addEventListener('mousedown', startDragging);
    btn.addEventListener('touchstart', startDragging, { passive: false });

    function startDragging(e) {
        if (!isMovable) return;
        isDragging = true;

        if (e.type === 'mousedown') {
            startX = e.clientX;
            startY = e.clientY;
        } else {
            e.preventDefault();
            startX = e.touches[0].clientX;
            startY = e.touches[0].clientY;
        }

        initialX = btn.offsetLeft;
        initialY = btn.offsetTop;

        document.addEventListener('mousemove', drag);
        document.addEventListener('touchmove', drag, { passive: false });
        document.addEventListener('mouseup', stopDragging);
        document.addEventListener('touchend', stopDragging);
    }

    function drag(e) {
        if (!isDragging) return;
        e.preventDefault();

        let currentX, currentY;
        if (e.type === 'mousemove') {
            currentX = e.clientX;
            currentY = e.clientY;
        } else {
            currentX = e.touches[0].clientX;
            currentY = e.touches[0].clientY;
        }

        const deltaX = currentX - startX;
        const deltaY = currentY - startY;

        const newLeft = initialX + deltaX;
        const newTop = initialY + deltaY;

        // 确保按钮不会超出视窗范围
        const maxX = window.innerWidth - btn.offsetWidth;
        const maxY = window.innerHeight - btn.offsetHeight;

        const btnLeft = Math.min(Math.max(0, newLeft), maxX);
        const btnTop = Math.min(Math.max(0, newTop), maxY);

        // 更新按钮位置
        const rightPos = `${window.innerWidth - btnLeft - btn.offsetWidth}px`;
        const bottomPos = `${window.innerHeight - btnTop - btn.offsetHeight}px`;

        btn.style.right = rightPos;
        btn.style.bottom = bottomPos;

        // 同步更新移动按钮位置
        moveBtn.style.right = `${parseInt(rightPos) + btn.offsetWidth + 10}px`;
        moveBtn.style.bottom = bottomPos;

        // 保存位置
        GM_setValue('btnRight', rightPos);
        GM_setValue('btnBottom', bottomPos);
    }

    function stopDragging() {
        if (isDragging) {
            isDragging = false;
            document.removeEventListener('mousemove', drag);
            document.removeEventListener('touchmove', drag);
            document.removeEventListener('mouseup', stopDragging);
            document.removeEventListener('touchend', stopDragging);
        }
    }

    let lastRecordedId = ''; // 记录最后一次记录的帖子 ID

    function recordVisit() {
        setTimeout(() => {
            const path = window.location.pathname;
            const postId = path.match(/\/t\/(\d+)/)?.[1] || path.match(/\/topic\/(\d+)/)?.[1];
            if (!postId) return;

            const title = document.querySelector('h1')?.textContent || document.title;
            const url = window.location.href;

            if (postId === lastRecordedId) return; // 避免重复记录
            lastRecordedId = postId;

            let history = GM_getValue('postHistory', []);

            // 检查是否存在相同帖子 ID
            const existingIndex = history.findIndex(item => item.id === postId);
            if (existingIndex !== -1) {
                history.splice(existingIndex, 1); // 删除重复记录
            }

            history.unshift({
                id: postId,
                title: title,
                url: url,
                time: new Date().toISOString(),
            });

            const maxRecords = Math.min(GM_getValue('maxRecords', 10), 20);
            if (history.length > maxRecords) {
                history = history.slice(0, maxRecords);
            }

            GM_setValue('postHistory', history);
        }, 1000);
    }

    function showHistory() {
        const history = GM_getValue('postHistory', []);
        popup.innerHTML = '';

        // 设置区域
        const settingsDiv = document.createElement('div');
        setElementStyle(settingsDiv, {
            marginBottom: '10px',
            padding: '5px',
            borderBottom: '1px solid #eee',
            display: 'flex',
            justifyContent: 'space-between',
            alignItems: 'center',
        });

        const settingsLabel = document.createElement('label');
        settingsLabel.textContent = '记录条数: ';
        const settingsInput = document.createElement('input');
        settingsInput.type = 'number';
        settingsInput.min = 1;
        settingsInput.max = 20;
        settingsInput.value = GM_getValue('maxRecords', 10);
        setElementStyle(settingsInput, {
            width: '60px',
            margin: '0 5px',
            padding: '3px',
            borderRadius: '4px',
            border: '1px solid #ddd',
        });
        settingsInput.onchange = (e) => {
            let value = parseInt(e.target.value, 10);
            value = Math.min(20, Math.max(1, value));
            e.target.value = value;
            GM_setValue('maxRecords', value);
        };

        const clearBtn = document.createElement('button');
        clearBtn.textContent = '清空记录';
        setElementStyle(clearBtn, {
            padding: '5px 10px',
            background: 'rgba(255, 68, 68, 0.9)',
            color: 'white',
            border: 'none',
            borderRadius: '15px',
            cursor: 'pointer',
            transition: 'all 0.3s ease',
        });
        clearBtn.onclick = () => {
            if (confirm('确定要清空所有浏览记录吗？')) {
                GM_setValue('postHistory', []);
                showHistory();
            }
        };

        settingsDiv.appendChild(settingsLabel);
        settingsDiv.appendChild(settingsInput);
        settingsDiv.appendChild(clearBtn);
        popup.appendChild(settingsDiv);

        if (history.length === 0) {
            popup.innerHTML += '<p style="text-align:center;color:#666;">暂无浏览记录</p>';
            return;
        }

        // 展示记录
        const ul = document.createElement('ul');
        setElementStyle(ul, {
            listStyle: 'none',
            margin: '0',
            padding: '0',
        });

        history.forEach((item, index) => {
            const li = document.createElement('li');
            setElementStyle(li, {
                padding: '10px',
                borderBottom: '1px solid #eee',
                cursor: 'pointer',
                transition: 'all 0.3s ease',
                borderRadius: '8px',
                display: 'flex',
                justifyContent: 'space-between',
                alignItems: 'center',
            });

            const time = new Date(item.time).toLocaleString();
            const titleDiv = document.createElement('div');
            titleDiv.innerHTML = `
                <div style="font-size:14px;margin-bottom:5px;">${item.title}</div>
                <div style="font-size:12px;color:#666;">${time}</div>
            `;
            titleDiv.style.flex = '1';
            titleDiv.onclick = () => {
                window.location.href = item.url;
            };

            const deleteBtn = document.createElement('button');
            deleteBtn.textContent = '删除';
            setElementStyle(deleteBtn, {
                padding: '5px 10px',
                background: 'rgba(255, 68, 68, 0.9)',
                color: 'white',
                border: 'none',
                borderRadius: '8px',
                cursor: 'pointer',
                marginLeft: '10px',
            });
            deleteBtn.onclick = (e) => {
                e.stopPropagation(); // 防止触发跳转
                if (confirm(`确定删除记录 "${item.title}" 吗？`)) {
                    history.splice(index, 1);
                    GM_setValue('postHistory', history);
                    showHistory();
                }
            };

            li.appendChild(titleDiv);
            li.appendChild(deleteBtn);
            ul.appendChild(li);
        });

        popup.appendChild(ul);
    }

    // 弹窗显示控制
    let isPopupVisible = false;
    btn.onclick = (e) => {
        if (!isMovable) {
            isPopupVisible = !isPopupVisible;
            popup.style.display = isPopupVisible ? 'block' : 'none';
            if (isPopupVisible) {
                // 更新弹窗位置为按钮上方
                const btnRect = btn.getBoundingClientRect();
                const popupRight = window.innerWidth - btnRect.right;
                popup.style.right = `${popupRight}px`;
                popup.style.bottom = `${parseInt(btn.style.bottom) + btn.offsetHeight + 10}px`;
                showHistory();
            }
        }
    };

    // 点击外部关闭弹窗
    document.addEventListener('click', (e) => {
        if (!popup.contains(e.target) && e.target !== btn && e.target !== moveBtn) {
            popup.style.display = 'none';
            isPopupVisible = false;
        }
    });

    // 初始记录
    recordVisit();

    // 监听 URL 变化
    let lastUrl = location.href;
    new MutationObserver(() => {
        if (location.href !== lastUrl) {
            lastUrl = location.href;
            recordVisit();
        }
    }).observe(document.body, { childList: true, subtree: true });
})();