function parseDate(date) {
    var months = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
                  'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
  
    return months[date.getUTCMonth()] + ' ' + date.getUTCDate() + ', ' + date.getUTCFullYear() + ' ' + date.toLocaleTimeString();
  }

function parseComment(comment) {
    const author = data.users[comment.user]
    if (author === undefined) {
        author = {}
    }
    const html = `
    <div class="comment">
        <a class="pfp">
        
        </a>
        <span>
            <span class="bold mtext">${author.first + ' ' + author.last}</span>
            <p class="mtext">${comment.content}</p>
        </span>
    </div>
    `
    return html
}

function parsePost(post) {
    const author = data.users[post.user]
    if (author === undefined) {
        author = {}
    }
    const html = `
    <div class="post" postid=${post.id}>
        <div class="postheader">
            <a class="pfp">
                
            </a>
            <div class="postname">
                <span class="bold">${author.first + ' ' + author.last}</span>
                <span class="gtext mtext">${parseDate(new Date(post.date))}</span>
            </div>
        </div>
        <p class="mtext">
            ${post.content.replace(/\n/g,'<br>')}
        </p>
        <span class="gtext mtext">
                ${Object.keys(post.likes).map(k => post.likes[k]).filter(v => v !== false).length} Likes
        </span>
        <div class="fullline nb"></div>
        <div class="postbuttons">
            <span onclick="like(this)">
                <i class="icons like ${post.likes[data.user.id] ? 'blue' : ''}"></i>
                <span class="bold ${post.likes[data.user.id] ? 'blue' : ''}">Like</span>
            </span>
            <span onclick="this.parentElement.parentElement.getElementsByClassName('newcomment')[0].focus()">
                <i class="icons comm"></i>
                <span class="bold">Comment</span>
            </span>
        </div>
        <div id="comments">
            <div class="fullline" style="margin-top: 0"></div>
            ${post.comments.map(parseComment).join('')}
            <div class="comment">
                <a class="pfp" href="profile">
                
                </a>
                <form onsubmit="comment(event)">
                    <input type="text" name="text" placeholder="Write a comment..." id="newcomment" class="newcomment">
                </form>
            </div>
        </div>
    </div>  
    `

    return html
}

function getPost(id) {
    for (let i = 0; i < data.posts.length; i++) {
        if (data.posts[i].id === id) {
            return id 
        }
    }
    return -1
}

async function like(span) {
    const id = parseInt(span.parentElement.parentElement.getAttribute('postid'))
    const post = data.posts[getPost(id)]
    const current = post.likes[data.user.id]
    const response = await postlike(id, !current)
    if (response.status != 200) return;
    post.likes[data.user.id] = !currentg
    render()
}

async function comment(event) {
    event.preventDefault();
    const text = event.target.elements.text.value.trim();
    if (text.length < 1) return;
    const id = parseInt(event.target.parentElement.parentElement.parentElement.getAttribute('postid'))
    var index = getPost(id);
    if (index === -1) return;
    const response = await postcomment(id, text)
    if (response.status != 200) return;
    event.target.elements.text.value = '';
    data.posts[index].comments.push({
        user: data.user.id,
        content: text
    })
    render()
}

async function post() {
    const text = document.getElementById("text").value.trim()
    const error = document.getElementsByClassName('error')[0]
    if (text.length < 1) return;
    const response = await createpost(text);
    if (response.status != 200) {
        error.innerHTML = response.msg
        return;
    }
    error.innerHTML = '';
    data.posts.unshift({
        id: response.msg,
        user: data.user.id,
        date: Date.now(),
        content: text,
        likes: [],
        comments: []
    })
    render()
}

function render() {
    const html = `
    <div id="posts">
        <div class="create">
            <a class="pfp" href="profile">
                    
            </a>
            <button class="pfp">
                <p class="gtext" onclick="document.getElementById('popup').classList.remove('hidden')">
                    What's on your mind, ${data.user.first}?
                </p>
            </button>
        </div>
        ${data.posts.map(p => parsePost(p)).join('')}
    </div>
    `
    
    add(html, 'posts')

    const popup = `
    <div id="popup" class="hidden">
        <div class="createpost">
            <div class="close" onclick="document.getElementById('popup').classList.add('hidden')"></div>
            <span class="ltext ctext bold">Create post</span>
            <div class="fullline"></div>
            <div class="postheader">
                <a class="pfp" style="cursor: auto">
                    
                </a>
                <div class="postname">
                    <span class="bold">${data.user.first + ' ' + data.user.last}</span>
                    <span class="gtext mtext">Now</span>
                </div>
            </div>
            <textarea type="text" name="text" id="text" placeholder="What's on your mind, ${data.user.first}?"></textarea>
            <span class="error ctext" style="padding-bottom: 15px; margin-top: -30px;"></span>
            <button class="primary" onclick="post(this)">Post</button>
        </div>
    </div>
    `

    add(popup, 'popup')

    const load = `
    <div id="load">
        <a class="bold gtext" onclick="load()">Load more posts</a>
    </div>
    `

    if (page !== -1) {
        add(load, 'load')
    } else {
        remove('load')
    }
}

var page = 0
const data = {
    user: {},
    users: {},
    posts: []
}

async function load() {
    const posts = (await loadposts(page)).json
    if (posts.length === 0) {
        page = -1
    } else {
        page++
    }
    data.posts.push(... posts)
    const batch = []
    for (const post of posts) {
        for(const comment of post.comments) {
            if (data.users[comment.user] !== undefined) continue
            if (batch.includes(comment.user)) continue
            batch.push(comment.user)
        }
        if (data.users[post.user] !== undefined) continue
        if (batch.includes(post.user)) continue
        batch.push(post.user)
    }
    const users = (await loadusers(batch)).json
    for (const id in users) {
        data.users[id] = users[id]
    }
    render()
}


async function init() {
    header(true, false)
    data.user = (await loadself()).json
    data.users[data.user.id] = data.user
    load()
}