export function createElement({ innerText, innerHTML, textContent, readOnly, children = [], dataset, style, classList = [], ...attributes }, tagName = 'div') {
    const element = document.createElement(tagName)
    for (const key in attributes) {
        if (key.startsWith('on')) element[key] = attributes[key] // 如果是事件则直接赋值
        else element.setAttribute(key, attributes[key])          // 否则是属性则使用setAttribute
    }
    if (dataset) Object.assign(element.dataset, dataset)
    if (style) Object.assign(element.style, style)
    if (classList.length) element.classList.add(...classList)
    if (textContent) element.textContent = textContent
    if (innerText) element.innerText = innerText
    if (innerHTML) element.innerHTML = innerHTML
    if (readOnly) element.readOnly = readOnly
    if (children) children.forEach(child => element.appendChild(child))
    return element
}

export function List(options) {
    return createElement(options, 'ul')
}

export function ListItem(options) {
    return createElement(options, 'li')
}

export function Span(options) {
    return createElement(options, 'span')
}

export function Button(options) {
    return createElement(options, 'button')
}

export function Input(options) {
    return createElement(options, 'input')
}

export function Avatar(options) {
    const element = createElement(options, 'img')
    element.onerror = () => element.src = '/favicon.ico'
    return element
}

export function UploadMusic(options) {
    let dragStats = null
    const drop = createElement({
        textContent: '点击或拖拽音乐到此处共享您的音乐',
        style: {
            width: '100%',
            color: '#999',
            lineHeight: '5rem',
            textAlign: 'center',
            position: 'absolute',
            top: 0,
            display: 'none'
        }
    })
    return createElement({
        ...options,
        style: {
            width: '100%',
            height: '10rem',
            backdropFilter: 'blur(5px)',
            backgroundColor: '#fcfcfc',
            borderRadius: '1em',
            border: '1px solid #f1f1f1',
            position: 'relative',
            userSelect: 'none',
            cursor: 'pointer',
            ...options.style
        },
        onclick: event => {
            // 临时创建一个input触发input的点击事件
            const input = Input({
                type: 'file',
                multiple: true,
                accept: 'audio/*',
                style: {
                    display: 'none',
                },
                onchange: event => {
                    const files = Array.from(event.target.files)
                    if (files.length === 0) return
                    options.onchange(files)
                }
            })
            input.click()
        },
        onmouseenter: event => {
            drop.style.display = 'block'
        },
        onmouseleave: event => {
            drop.style.display = 'none'
        },
        ondragover: event => {
            console.log('dragover')
            event.preventDefault()
            event.stopPropagation()
            if (dragStats) return
            event.dataTransfer.dropEffect = 'copy'
            drop.style.display = 'block'
        },
        ondragleave: event => {
            event.preventDefault()
            event.stopPropagation()
            if (dragStats) return
            clearTimeout(dragStats)
            dragStats = setTimeout(() => {
                drop.style.display = 'none'
                dragStats = null
            }, 1000)
        },
        ondrop: event => {
            console.log('drop')
            event.preventDefault()
            event.stopPropagation()
            const files = Array.from(event.dataTransfer.files)
            // 检查必须是音乐文件, 移除其它文件
            for (let i = 0; i < files.length; i++) {
                if (!files[i].type.startsWith('audio/')) {
                    files.splice(i, 1)
                    i--
                }
            }
            if (files.length === 0) return console.log('没有文件')
            console.log('files', files)
            options.onchange(files)
        },
        children: [
            // 绘制一个云朵上传图标(别放弃...还有我呢!)
            createElement({
                style: {
                    width: '82px',
                    height: '30px',
                    background: '#e7f4fd',
                    background: '-webkit-linear-gradient(top,#e7f4fd 5%,#ceedfd 100%)',
                    borderRadius: '25px',
                    position: 'relative',
                    margin: '33px auto 5px'
                },
                children: [
                    createElement({
                        style: {
                            width: '45px',
                            height: '45px',
                            top: '-22px',
                            right: '12px',
                            borderRadius: '50px',
                            borderRadius: '25px',
                            background: '#e7f4fd',
                            position: 'absolute',
                            zIndex: '-1'
                        }
                    }),
                    createElement({
                        style: {
                            width: '25px',
                            height: '25px',
                            top: '-12px',
                            left: '12px',
                            borderRadius: '25px',
                            background: '#e7f4fd',
                            position: 'absolute',
                            zIndex: '-1'
                        }
                    }),
                    Span({
                        width: '87px',
                        position: 'absolute',
                        bottom: '-2px',
                        background: '#000',
                        zIndex: '-1',
                        boxShadow: '0 0 6px 2px rgba(0,0,0,0.1)',
                        borderRadius: '50%'
                    }),
                    createElement({
                        textContent: '♫',
                        style: {
                            display: 'flex',
                            justifyContent: 'center',
                            alignItems: 'center',
                            fontSize: '3rem',
                            fontWeight: 'bold',
                            position: 'relative',
                            top: '-1.5rem',
                            color: '#e7f4fd',
                            textShadow: '0 1px 1px #fff'
                            //textShadow: '0 0 5px #000, 0 0 10px #000, 0 0 15px #000, 0 0 20px #000, 0 0 25px #000, 0 0 30px #000, 0 0 35px #000, 0 0 40px #000, 0 0 45px #000, 0 0 50px #000, 0 0 55px #000, 0 0 60px #000, 0 0 65px #000, 0 0 70px #000, 0 0 75px #000'
                        }
                    })
                ]
            }),
            drop
        ]
    })
}

// 弹出窗口, 高斯模糊背景, 进入离开动画过渡
export function Dialog(options) {
    const element = createElement({
        tabIndex: 0,
        style: {
            position: 'fixed',
            top: 0,
            left: 0,
            zIndex: 1000,
            width: '100%',
            height: '100%',
            backdropFilter: 'blur(5px)',
            duration: '0.5s',
            transition: 'all 0.5s'
        },
        onclick: async event => {
            // 判断必须是点击自身, 而不是子元素
            if (event.target !== event.currentTarget) return
            await event.target.animate([{ opacity: 1 }, { opacity: 0 }], { duration: 100 }).finished
            await event.target.remove()
        },
        onkeydown: async event => {
            if (event.key !== 'Escape') return
            await event.target.animate([{ opacity: 1 }, { opacity: 0 }], { duration: 100 }).finished
            await event.target.remove()
        },
        children: [
            createElement({
                ...options,
                style: {
                    position: 'fixed',
                    top: '50%',
                    left: '50%',
                    transform: 'translate(-50%, -50%)',
                    backgroundColor: '#fff',
                    borderRadius: '150px',
                    boxShadow: '0 0 1em #ccc',
                    overflow: 'hidden',
                    display: 'flex',
                    justifyContent: 'center',
                    ...options.style,
                }
            })
        ]
    })
    // 显示时自动聚焦
    const observer = new MutationObserver(mutationsList => {
        for (const mutation of mutationsList) {
            if (mutation.type === 'childList' && mutation.addedNodes.length > 0) {
                element.focus()
                element.animate([{ opacity: 0 }, { opacity: 1 }], { duration: 100 }).finished
                return observer.disconnect()
            }
        }
    })
    observer.observe(document.body, { childList: true, subtree: true })
    return element
}

// 深度代理, 用于监听数据的变化
export function useProxy(data, callback, path = []) {
    if (Array.isArray(data)) {
        const array = class extends Array {
            constructor(args) {
                super(args)
            }
            push(args) {
                super.push(args)
                console.log('push', args)
                this.__notify()
            }
            pop(...args) {
                const result = super.pop(...args)
                console.log('pop')
                this.__notify()
                return result
            }
            shift(...args) {
                const result = super.shift(...args)
                this.__notify()
                return result
            }
            unshift(...args) {
                super.unshift(...args)
                this.__notify()
            }
            splice(...args) {
                super.splice(...args)
                this.__notify()
            }
            deleteProperty(...args) {
                console.log('deleteProperty', ...args)
                super.deleteProperty(...args)
                this.__notify()
            }
            __notify() {
                if (callback) callback()
            }
        }
        //console.log('为数组每项递归创建代理')
        data.forEach((item, index) => {
            data[index] = useProxy(item, callback, [...path, index])
        })
        return new array(...data)
    }
    if (typeof data === 'object' && data !== null) {
        //console.log('为对象属性递归创建代理')
        Object.keys(data).forEach(key => {
            if (typeof data[key] === 'object' && data[key] !== null) {
                data[key] = useProxy(data[key], callback, [...path, key])
            }
        })
        return new Proxy(data, {
            deleteProperty(target, key) {
                console.log('deleteProperty', key)
                return delete target[key]
            }
        })
    }
    console.log('为其它类型直接返回')
    return data
}