const STATE = {
    id: 0,
    chat_id: "",
    observer: null,
    is_loading: false,
    stream_element: null,
    last_message_time: 0,
    replying_to: undefined,
    last_read_receipt_load: 0,
};

function create_streamer(chat_id, hook_element) {
    STATE.chat_id = chat_id;
    STATE.stream_element = hook_element.parentElement;
    clear_notifications();

    STATE.observer = new IntersectionObserver(
        (entries) => {
            load_messages();
        },
        {
            root: document.body,
            rootMargin: "0px",
            scrollMargin: "0px",
            threshold: 1.0,
        },
    );

    STATE.observer.observe(hook_element);
    read_receipt();
}

function load_messages() {
    if (STATE.is_loading) {
        return;
    }

    STATE.is_loading = true;
    STATE.id += 1;

    fetch(
        `/chats/_templates/chat/${STATE.chat_id}/messages/before/${STATE.last_message_time}?use_id=${STATE.id}`,
    )
        .then((res) => res.text())
        .then((res) => {
            setTimeout(() => {
                STATE.is_loading = false;
            }, 2000);

            STATE.stream_element.innerHTML += res;
            STATE.last_message_time = Number.parseInt(
                document
                    .getElementById(`msgs_data_${STATE.id}`)
                    .getAttribute("data-first-message-time"),
            );

            if (document.getElementById(`msgs_quit_${STATE.id}`)) {
                STATE.observer.disconnect();
                console.log("quit");
            } else {
                STATE.observer.unobserve(
                    STATE.stream_element.querySelector(
                        "[ui_ident=data_marker]",
                    ),
                );

                STATE.stream_element
                    .querySelector("[ui_ident=data_marker]")
                    .remove();

                const element = document.createElement("div");
                element.setAttribute("ui_ident", "data_marker");
                STATE.stream_element.append(element);
                STATE.observer.observe(element);
            }
        });
}

function render_message(id) {
    STATE.is_loading = true;
    fetch(`/chats/_templates/message/${id}`)
        .then((res) => res.text())
        .then((res) => {
            STATE.is_loading = false;
            STATE.stream_element.innerHTML = `${res}${STATE.stream_element.innerHTML}`;
            mark_message_read();
            scroll_bottom();

            if (document.getElementById("delivered_read_status")) {
                document.getElementById("delivered_read_status").remove(); // clear read receipt box
            }
        });
}

function scroll_bottom() {
    STATE.stream_element.parentElement.scrollTo(
        0,
        STATE.stream_element.parentElement.scrollHeight,
    );
}

function sock_con() {
    const socket = new WebSocket(
        `//${window.location.origin.split("//")[1]}/api/v1/chats/${STATE.chat_id}/_connect`,
    );

    socket.addEventListener("message", async (event) => {
        if (event.data === "Ping") {
            return socket.send("Pong");
        }

        const msg = JSON.parse(event.data);

        if (msg.method === "MessageCreate") {
            render_message(msg.body);

            setTimeout(() => {
                clear_notifications();
            }, 150);
        } else if (msg.method === "MessageDelete") {
            if (document.getElementById(`message_${msg.body}`)) {
                document.getElementById(`message_${msg.body}`).remove();
            }
        } else if (msg.method === "MessageUpdate") {
            const [id, content] = JSON.parse(msg.body);
            document.getElementById(`${id}_body`).innerHTML =
                await render_markdown(content);
        } else if (msg.method === "ReadReceipt") {
            setTimeout(() => {
                read_receipt();
            }, 150);
        }
    });
}

function create_message(e) {
    e.preventDefault();

    const body = new FormData();

    // attach images
    if (e.target.images) {
        for (const file of e.target.images.files) {
            body.append(file.name, file);
        }
    }

    // add json body
    body.append(
        "body",
        JSON.stringify({
            content: e.target.content.value,
            replying_to: STATE.replying_to,
        }),
    );

    // send request
    fetch(`/api/v1/messages/${STATE.chat_id}`, { method: "POST", body })
        .then((res) => res.json())
        .then((res) => {
            if (res.ok) {
                e.target.reset();
                document.getElementById("images_zone").classList.add("hidden");
                clear_replying_to();
            } else {
                show_message(res.message, res.ok);
            }
        });
}

function mark_message_read() {
    fetch(`/api/v1/chats/${STATE.chat_id}/read_message`, {
        method: "POST",
    })
        .then((res) => res.json())
        .then((res) => {
            if (!res.ok) {
                show_message(res.message, res.ok);
            }
        });
}

function read_receipt() {
    if (new Date().getTime() - STATE.last_read_receipt_load < 150) {
        console.log("too soon");
        return;
    }

    STATE.last_read_receipt_load = new Date().getTime();

    if (document.getElementById("delivered_read_status")) {
        document.getElementById("delivered_read_status").remove();
    }

    fetch(`/chats/_templates/chat/${STATE.chat_id}/read_receipt`)
        .then((res) => res.text())
        .then((res) => {
            document.getElementById("read_receipt_zone").innerHTML = res;
        });
}

function delete_message(id) {
    if (!confirm("Are you sure you want to do this?")) {
        return;
    }

    fetch(`/api/v1/messages/${id}`, {
        method: "DELETE",
    })
        .then((res) => res.json())
        .then((res) => {
            if (!res.ok) {
                show_message(res.message, res.ok);
            }
        });
}

async function render_markdown(content) {
    return await (
        await fetch("/api/v1/markdown", {
            method: "POST",
            headers: { "Content-Type": "application/json" },
            body: JSON.stringify({ content }),
        })
    ).text();
}

function edit_message_ui(id) {
    document.getElementById(`${id}_body`).classList.add("hidden");
    document.getElementById(`${id}_edit_area`).classList.remove("hidden");
}

function edit_message(id, e) {
    e.preventDefault();

    fetch(`/api/v1/messages/${id}`, {
        method: "PUT",
        headers: {
            "Content-Type": "application/json",
        },
        body: JSON.stringify({
            content: e.target.content.value,
        }),
    })
        .then((res) => res.json())
        .then(async (res) => {
            if (!res.ok) {
                show_message(res.message, res.ok);
            } else {
                document
                    .getElementById(`${id}_body`)
                    .classList.remove("hidden");
                document
                    .getElementById(`${id}_edit_area`)
                    .classList.add("hidden");
            }
        });
}

function leave_chat(id) {
    if (!confirm("Are you sure you would like to do this?")) {
        return;
    }

    fetch(`/api/v1/chats/${id}/leave`, {
        method: "POST",
    })
        .then((res) => res.json())
        .then((res) => {
            show_message(res.message, res.ok);
        });
}

function add_member_to_chat(e, chat_id) {
    e.preventDefault();
    document.getElementById("add_user_dialog").close();
    fetch(`/api/v1/chats/${chat_id}/members/add/${e.target.username.value}`, {
        method: "POST",
    })
        .then((res) => res.json())
        .then((res) => {
            show_message(res.message, res.ok);
        });
}

function update_chat_info(id, info) {
    fetch(`/api/v1/chats/${id}/info`, {
        method: "POST",
        headers: {
            "Content-Type": "application/json",
        },
        body: JSON.stringify({
            info,
        }),
    })
        .then((res) => res.json())
        .then((res) => {
            show_message(res.message, res.ok);
        });
}

function rename_chat(id, info) {
    const new_name = prompt("New name:");

    if (!new_name) {
        return;
    }

    info.name = new_name;
    update_chat_info(id, info);
}

function remove_member_from_chat(chat_id, uid) {
    if (!confirm("Are you sure you would like to do this?")) {
        return;
    }

    fetch(`/api/v1/chats/${chat_id}/members/remove/${uid}`, {
        method: "POST",
    })
        .then((res) => res.json())
        .then((res) => {
            show_message(res.message, res.ok);
        });
}

function create_direct_chat_with_user(id) {
    fetch(`/api/v1/chats`, {
        method: "POST",
        headers: {
            "Content-Type": "application/json",
        },
        body: JSON.stringify({
            style: "Direct",
            members: [id],
        }),
    })
        .then((res) => res.json())
        .then((res) => {
            if (!res.ok) {
                show_message(res.message, res.ok);
            } else {
                window.location.href = `/chats/${res.payload}`;
            }
        });
}

function pin_message(e, id) {
    fetch(`/api/v1/chats/${STATE.chat_id}/pins/${id}`, {
        method: "POST",
    })
        .then((res) => res.json())
        .then((res) => {
            show_message(res.message, res.ok);

            if (res.ok) {
                e.target.remove();
            }
        });
}

function unpin_message(id) {
    fetch(`/api/v1/chats/${STATE.chat_id}/pins/${id}`, {
        method: "DELETE",
    })
        .then((res) => res.json())
        .then((res) => {
            show_message(res.message, res.ok);
        });
}

function display_pending_images(e) {
    document.getElementById("images_zone").innerHTML = "";
    document.getElementById("images_zone").classList.remove("hidden");

    if (e.target.files.length < 1) {
        document.getElementById("images_zone").classList.add("hidden");
        return;
    }

    let idx = 0;
    for (const file of e.target.files) {
        document.getElementById("images_zone").innerHTML +=
            `<button class="button surface" onclick="remove_file_from_picker('images', ${idx})">${file.name}</button>`;
        idx += 1;
    }
}

function remove_file_from_picker(input_id, idx) {
    const input = document.getElementById(input_id);
    const files = Array.from(input.files);
    files.splice(idx - 1, 1);

    // update files
    const list = new DataTransfer();

    for (item of files) {
        list.items.add(item);
    }

    input.files = list.files;

    // render
    display_pending_images({ target: input });
}

function reply_to_message(id) {
    STATE.replying_to = id;
    document.getElementById("replying_to_zone").classList.remove("hidden");
    document.getElementById(`message_${id}`).classList.add("card");
    document.getElementById(`message_${id}`).classList.add("surface");
    scroll_bottom();
}

function clear_replying_to() {
    if (STATE.replying_to) {
        document
            .getElementById(`message_${STATE.replying_to}`)
            .classList.remove("card");
        document
            .getElementById(`message_${STATE.replying_to}`)
            .classList.remove("surface");
    }

    STATE.replying_to = undefined;
    document.getElementById("replying_to_zone").classList.add("hidden");
}

function clear_notifications() {
    fetch(`/api/v1/chats/${STATE.chat_id}/notifications`, {
        method: "DELETE",
    })
        .then((res) => res.json())
        .then((res) => {
            if (!res.ok) {
                show_message(res.message, res.ok);
            }
        });
}