// Populate the sidebar
//
// This is a script, and not included directly in the page, to control the total size of the book.
// The TOC contains an entry for each page, so if each page includes a copy of the TOC,
// the total size of the page becomes O(n**2).
class MDBookSidebarScrollbox extends HTMLElement {
    constructor() {
        super();
    }
    connectedCallback() {
        this.innerHTML = '<ol class="chapter"><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="index.html">前言</a></span></li><li class="chapter-item expanded "><li class="spacer"></li></li><li class="chapter-item expanded "><li class="part-title">第一部分：基础架构</li></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part1-foundation/ch01-overview.html"><strong aria-hidden="true">1.</strong> 第 1 章：全景概览</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part1-foundation/ch02-bootstrap.html"><strong aria-hidden="true">2.</strong> 第 2 章：启动流程</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part1-foundation/ch03-type-system.html"><strong aria-hidden="true">3.</strong> 第 3 章：类型系统设计</a></span></li><li class="chapter-item expanded "><li class="part-title">第二部分：核心引擎</li></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part2-core-engine/ch04-query-engine.html"><strong aria-hidden="true">4.</strong> 第 4 章：查询引擎</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part2-core-engine/ch05-message-system.html"><strong aria-hidden="true">5.</strong> 第 5 章：消息系统</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part2-core-engine/ch06-streaming.html"><strong aria-hidden="true">6.</strong> 第 6 章：流式处理</a></span></li><li class="chapter-item expanded "><li class="part-title">第三部分：工具系统</li></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part3-tool-system/ch07-tool-architecture.html"><strong aria-hidden="true">7.</strong> 第 7 章：工具架构</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part3-tool-system/ch08-builtin-tools.html"><strong aria-hidden="true">8.</strong> 第 8 章：内置工具深度解析</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part3-tool-system/ch09-tool-execution.html"><strong aria-hidden="true">9.</strong> 第 9 章：工具执行管线</a></span></li><li class="chapter-item expanded "><li class="part-title">第四部分：Agent 系统</li></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part4-agent/ch10-agent-model.html"><strong aria-hidden="true">10.</strong> 第 10 章：Agent 模型</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part4-agent/ch11-subagent.html"><strong aria-hidden="true">11.</strong> 第 11 章：子 Agent 编排</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part4-agent/ch12-skill-system.html"><strong aria-hidden="true">12.</strong> 第 12 章：Skill 系统</a></span></li><li class="chapter-item expanded "><li class="part-title">第五部分：权限与安全</li></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part5-permission/ch13-permission-model.html"><strong aria-hidden="true">13.</strong> 第 13 章：权限模型</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part5-permission/ch14-bash-security.html"><strong aria-hidden="true">14.</strong> 第 14 章：Bash 安全分析</a></span></li><li class="chapter-item expanded "><li class="part-title">第六部分：MCP 协议</li></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part6-mcp/ch15-mcp-protocol.html"><strong aria-hidden="true">15.</strong> 第 15 章：MCP 协议实现</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part6-mcp/ch16-mcp-auth.html"><strong aria-hidden="true">16.</strong> 第 16 章：MCP 认证体系</a></span></li><li class="chapter-item expanded "><li class="part-title">第七部分：状态管理</li></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part7-state/ch17-state-management.html"><strong aria-hidden="true">17.</strong> 第 17 章：状态管理</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part7-state/ch18-conversation.html"><strong aria-hidden="true">18.</strong> 第 18 章：会话管理与压缩</a></span></li><li class="chapter-item expanded "><li class="part-title">第八部分：终端 UI</li></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part8-ui/ch19-ink-react.html"><strong aria-hidden="true">19.</strong> 第 19 章：React + Ink 终端 UI</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part8-ui/ch20-repl.html"><strong aria-hidden="true">20.</strong> 第 20 章：REPL 实现</a></span></li><li class="chapter-item expanded "><li class="part-title">第九部分：工程实践</li></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part9-engineering/ch21-performance.html"><strong aria-hidden="true">21.</strong> 第 21 章：性能优化</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part9-engineering/ch22-testing.html"><strong aria-hidden="true">22.</strong> 第 22 章：测试策略</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part9-engineering/ch23-build-system.html"><strong aria-hidden="true">23.</strong> 第 23 章：构建系统</a></span></li><li class="chapter-item expanded "><li class="part-title">第十部分：编程思想</li></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part10-philosophy/ch24-design-patterns.html"><strong aria-hidden="true">24.</strong> 第 24 章：设计模式提炼</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="part10-philosophy/ch25-philosophy.html"><strong aria-hidden="true">25.</strong> 第 25 章：工程哲学</a></span></li><li class="chapter-item expanded "><li class="spacer"></li></li><li class="chapter-item expanded "><li class="part-title">附录</li></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="appendix/appendix-a-glossary.html"><strong aria-hidden="true">26.</strong> 附录 A：术语表</a></span></li><li class="chapter-item expanded "><span class="chapter-link-wrapper"><a href="appendix/appendix-b-source-map.html"><strong aria-hidden="true">27.</strong> 附录 B：源码导航</a></span></li></ol>';
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        let current_page = document.location.href.toString().split('#')[0].split('?')[0];
        if (current_page.endsWith('/')) {
            current_page += 'index.html';
        }
        const links = Array.prototype.slice.call(this.querySelectorAll('a'));
        const l = links.length;
        for (let i = 0; i < l; ++i) {
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            const href = link.getAttribute('href');
            if (href && !href.startsWith('#') && !/^(?:[a-z+]+:)?\/\//.test(href)) {
                link.href = path_to_root + href;
            }
            // The 'index' page is supposed to alias the first chapter in the book.
            if (link.href === current_page
                || i === 0
                && path_to_root === ''
                && current_page.endsWith('/index.html')) {
                link.classList.add('active');
                let parent = link.parentElement;
                while (parent) {
                    if (parent.tagName === 'LI' && parent.classList.contains('chapter-item')) {
                        parent.classList.add('expanded');
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                    parent = parent.parentElement;
                }
            }
        }
        // Track and set sidebar scroll position
        this.addEventListener('click', e => {
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                const clientRect = e.target.getBoundingClientRect();
                const sidebarRect = this.getBoundingClientRect();
                sessionStorage.setItem('sidebar-scroll-offset', clientRect.top - sidebarRect.top);
            }
        }, { passive: true });
        const sidebarScrollOffset = sessionStorage.getItem('sidebar-scroll-offset');
        sessionStorage.removeItem('sidebar-scroll-offset');
        if (sidebarScrollOffset !== null) {
            // preserve sidebar scroll position when navigating via links within sidebar
            const activeSection = this.querySelector('.active');
            if (activeSection) {
                const clientRect = activeSection.getBoundingClientRect();
                const sidebarRect = this.getBoundingClientRect();
                const currentOffset = clientRect.top - sidebarRect.top;
                this.scrollTop += currentOffset - parseFloat(sidebarScrollOffset);
            }
        } else {
            // scroll sidebar to current active section when navigating via
            // 'next/previous chapter' buttons
            const activeSection = document.querySelector('#mdbook-sidebar .active');
            if (activeSection) {
                activeSection.scrollIntoView({ block: 'center' });
            }
        }
        // Toggle buttons
        const sidebarAnchorToggles = document.querySelectorAll('.chapter-fold-toggle');
        function toggleSection(ev) {
            ev.currentTarget.parentElement.parentElement.classList.toggle('expanded');
        }
        Array.from(sidebarAnchorToggles).forEach(el => {
            el.addEventListener('click', toggleSection);
        });
    }
}
window.customElements.define('mdbook-sidebar-scrollbox', MDBookSidebarScrollbox);


// ---------------------------------------------------------------------------
// Support for dynamically adding headers to the sidebar.

(function() {
    // This is used to detect which direction the page has scrolled since the
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    let lastKnownScrollPosition = 0;
    // This is the threshold in px from the top of the screen where it will
    // consider a header the "current" header when scrolling down.
    const defaultDownThreshold = 150;
    // Same as defaultDownThreshold, except when scrolling up.
    const defaultUpThreshold = 300;
    // The threshold is a virtual horizontal line on the screen where it
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    // This is used to disable updates while scrolling. This is needed when
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    // is somewhat finicky to detect when the scroll has finished, so this
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    let disableScroll = false;
    // Array of header elements on the page.
    let headers;
    // Array of li elements that are initially collapsed headers in the sidebar.
    // I'm not sure why eslint seems to have a false positive here.
    // eslint-disable-next-line prefer-const
    let headerToggles = [];
    // This is a debugging tool for the threshold which you can enable in the console.
    let thresholdDebug = false;

    // Updates the threshold based on the scroll position.
    function updateThreshold() {
        const scrollTop = window.pageYOffset || document.documentElement.scrollTop;
        const windowHeight = window.innerHeight;
        const documentHeight = document.documentElement.scrollHeight;

        // The number of pixels below the viewport, at most documentHeight.
        // This is used to push the threshold down to the bottom of the page
        // as the user scrolls towards the bottom.
        const pixelsBelow = Math.max(0, documentHeight - (scrollTop + windowHeight));
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        const pixelsAbove = Math.max(0, defaultDownThreshold - scrollTop);
        // How much the threshold should be offset once it gets close to the
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        const bottomAdd = Math.max(0, windowHeight - pixelsBelow - defaultDownThreshold);
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        // Adjusts bottomAdd for a small document. The calculation above
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            const t = 1 - pixelsBelow / Math.max(1, maxPixelsBelow);
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        }

        let scrollingDown = true;
        if (scrollTop < lastKnownScrollPosition) {
            scrollingDown = false;
        }

        if (scrollingDown) {
            // When scrolling down, move the threshold up towards the default
            // downwards threshold position. If near the bottom of the page,
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            const amountScrolledDown = scrollTop - lastKnownScrollPosition;
            const adjustedDefault = defaultDownThreshold + adjustedBottomAdd;
            threshold = Math.max(adjustedDefault, threshold - amountScrolledDown);
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            // When scrolling up, move the threshold down towards the default
            // upwards threshold position. If near the bottom of the page,
            // quickly transition the threshold back up where it normally
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            const amountScrolledUp = lastKnownScrollPosition - scrollTop;
            const adjustedDefault = defaultUpThreshold - pixelsAbove
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            threshold = Math.min(adjustedDefault, threshold + amountScrolledUp);
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        if (documentHeight <= windowHeight) {
            threshold = 0;
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        if (thresholdDebug) {
            const id = 'mdbook-threshold-debug-data';
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                data.id = id;
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                    z-index: 9999;
                    pointer-events: none;
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            data.innerHTML = `
                <table>
                  <tr><td>documentHeight</td><td>${documentHeight.toFixed(1)}</td></tr>
                  <tr><td>windowHeight</td><td>${windowHeight.toFixed(1)}</td></tr>
                  <tr><td>scrollTop</td><td>${scrollTop.toFixed(1)}</td></tr>
                  <tr><td>pixelsAbove</td><td>${pixelsAbove.toFixed(1)}</td></tr>
                  <tr><td>pixelsBelow</td><td>${pixelsBelow.toFixed(1)}</td></tr>
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                </table>
            `;
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            width: 100vw;
            height: 2px;
            background-color: red;
            z-index: 9999;
            pointer-events: none;
        `;
        document.body.appendChild(line);
    }

    function mdbookEnableThresholdDebug() {
        thresholdDebug = true;
        updateThreshold();
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    }

    window.mdbookEnableThresholdDebug = mdbookEnableThresholdDebug;

    // Updates which headers in the sidebar should be expanded. If the current
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    }

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    function updateCurrentHeader() {
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            return;
        }

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        const els = document.getElementsByClassName('current-header');
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                break;
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            const windowHeight = window.innerHeight;
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            return;
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        a.classList.add('current-header');

        updateHeaderExpanded(a);
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    // Updates which header is "current" based on the threshold line.
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            return;
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        updateThreshold();
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    // When clicking on a header in the sidebar, this adjusts the threshold so
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        disableScroll = true;
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        }, 100);
        // requestAnimationFrame is used to delay the update of the "current"
        // header until after the scroll is done, and the header is in the new
        // position.
        requestAnimationFrame(() => {
            requestAnimationFrame(() => {
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                const href = a.getAttribute('href');
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                const targetElement = document.getElementById(targetId);
                if (targetElement) {
                    threshold = targetElement.getBoundingClientRect().bottom;
                    updateCurrentHeader();
                }
            });
        });
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    // Takes the nodes from the given head and copies them over to the
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    function filterHeader(source, dest) {
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            mark.replaceWith(...mark.childNodes);
        });
        dest.append(...clone.childNodes);
    }

    // Scans page for headers and adds them to the sidebar.
    document.addEventListener('DOMContentLoaded', function() {
        const activeSection = document.querySelector('#mdbook-sidebar .active');
        if (activeSection === null) {
            return;
        }

        const main = document.getElementsByTagName('main')[0];
        headers = Array.from(main.querySelectorAll('h2, h3, h4, h5, h6'))
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        if (headers.length === 0) {
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            ol.classList.add('section');
            if (stack.length > 0) {
                stack[stack.length - 1].ol.appendChild(ol);
            }
            stack.push({level: i + 1, ol: ol});
        }

        // The level where it will start folding deeply nested headers.
        const foldLevel = 3;

        for (let i = 0; i < headers.length; i++) {
            const header = headers[i];
            const level = parseInt(header.tagName.charAt(1));

            const currentLevel = stack[stack.length - 1].level;
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                    const ol = document.createElement('ol');
                    ol.classList.add('section');
                    const last = stack[stack.length - 1];
                    const lastChild = last.ol.lastChild;
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                    // level, which doesn't have a list item to place this new
                    // list inside of.
                    if (lastChild) {
                        lastChild.appendChild(ol);
                    } else {
                        last.ol.appendChild(ol);
                    }
                    stack.push({level: nextLevel, ol: ol});
                }
            } else if (level < currentLevel) {
                while (stack.length > 1 && stack[stack.length - 1].level > level) {
                    stack.pop();
                }
            }

            const li = document.createElement('li');
            li.classList.add('header-item');
            li.classList.add('expanded');
            if (level < foldLevel) {
                li.classList.add('expanded');
            }
            const span = document.createElement('span');
            span.classList.add('chapter-link-wrapper');
            const a = document.createElement('a');
            span.appendChild(a);
            a.href = '#' + header.id;
            a.classList.add('header-in-summary');
            filterHeader(header.children[0], a);
            a.addEventListener('click', headerThresholdClick);
            const nextHeader = headers[i + 1];
            if (nextHeader !== undefined) {
                const nextLevel = parseInt(nextHeader.tagName.charAt(1));
                if (nextLevel > level && level >= foldLevel) {
                    const toggle = document.createElement('a');
                    toggle.classList.add('chapter-fold-toggle');
                    toggle.classList.add('header-toggle');
                    toggle.addEventListener('click', () => {
                        li.classList.toggle('expanded');
                    });
                    const toggleDiv = document.createElement('div');
                    toggleDiv.textContent = '❱';
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                    span.appendChild(toggle);
                    headerToggles.push(li);
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            li.appendChild(span);

            const currentParent = stack[stack.length - 1];
            currentParent.ol.appendChild(li);
        }

        const onThisPage = document.createElement('div');
        onThisPage.classList.add('on-this-page');
        onThisPage.append(stack[0].ol);
        const activeItemSpan = activeSection.parentElement;
        activeItemSpan.after(onThisPage);
    });

    document.addEventListener('DOMContentLoaded', reloadCurrentHeader);
    document.addEventListener('scroll', reloadCurrentHeader, { passive: true });
})();

