//! # Conversations controller
//!
//! @author Pierre Hubert

use std::collections::HashMap;

use crate::api_data::conversation_api::ConversationAPI;
use crate::api_data::conversation_message_api::ConversationMessageAPI;
use crate::api_data::conversations_refresh_api::ConversationRefreshResultAPI;
use crate::api_data::list_unread_conversations_api::UnreadConversationAPI;
use crate::api_data::res_count_unread_conversations::ResultCountUnreadConversations;
use crate::api_data::res_create_conversation::ResCreateConversation;
use crate::api_data::res_find_private_conversations::ResFindPrivateConversations;
use crate::controllers::routes::RequestResult;
use crate::data::http_request_handler::HttpRequestHandler;
use crate::data::new_conversation::NewConversation;
use crate::data::new_conversation_message::NewConversationMessage;
use crate::data::user::UserID;
use crate::helpers::{conversations_helper, user_helper};
use crate::utils::string_utils::remove_html_nodes;

/// Create a new conversation
pub fn create(r: &mut HttpRequestHandler) -> RequestResult {
    let name = r.post_string("name")?;
    let mut members = r.post_numbers_list("users", 1)?
        .iter()
        .map(|f| UserID::new(f.clone()))
        .collect::<Vec<UserID>>();

    // Adapt name
    let name = match name.as_str() {
        "false" => None,
        s => Some(s.to_string())
    };

    // Check if members exists
    for user in &members {
        if !user_helper::exists(user)? {
            r.not_found(format!("User {} not found!", user.id()))?;
        }
    }

    // Add current user ID if required
    let curr_user_id = r.user_id()?;
    if !members.contains(&curr_user_id) {
        members.push(curr_user_id);
    }

    let conv = NewConversation {
        owner_id: r.user_id()?,
        name,
        owner_following: r.post_bool("follow")?,
        members,
        can_everyone_add_members: r.post_bool_opt("canEveryoneAddMembers", true),
    };

    // Create the conversation
    let conv_id = conversations_helper::create(&conv)?;
    r.set_response(ResCreateConversation::new(conv_id))
}

/// Get the list of conversations of a user
pub fn get_list(r: &mut HttpRequestHandler) -> RequestResult {
    let list = conversations_helper::get_list_user(&r.user_id()?)?;

    r.set_response(list.iter().map(|c| ConversationAPI::new(c)).collect::<Vec<ConversationAPI>>())
}

/// Get information about a single conversation
pub fn get_single(r: &mut HttpRequestHandler) -> RequestResult {
    let conversation_id = r.post_conv_id("conversationID")?;
    let conv = conversations_helper::get_single(conversation_id, &r.user_id()?)?;

    r.set_response(ConversationAPI::new(&conv))
}

/// Update the settings of a conversation
pub fn update_settings(r: &mut HttpRequestHandler) -> RequestResult {
    let conv_id = r.post_conv_id("conversationID")?;
    let is_moderator = conversations_helper::is_user_moderator(&r.user_id()?, conv_id)?;

    // Update following state, if required
    if r.has_post_parameter("following") {
        conversations_helper::set_following(
            &r.user_id()?,
            conv_id,
            r.post_bool("following")?,
        )?;
    }

    // Update members list
    if r.has_post_parameter("members") {
        let mut members = r.post_numbers_list("members", 1)?
            .iter()
            .map(|f| UserID::new(f.clone()))
            .collect::<Vec<UserID>>();

        let can_everyone_add_members = conversations_helper::can_everyone_add_members(conv_id)?;

        if !is_moderator && !can_everyone_add_members {
            r.forbidden("You can not update the list of members of this conversation!".to_string())?;
        }

        // Check if the members of the conversation really exists
        for member in &members {
            if !user_helper::exists(member)? {
                r.not_found(format!("User {} not found!", member.id()))?;
            }
        }

        if !members.contains(&r.user_id()?) {
            members.push(r.user_id()?);
        }

        conversations_helper::set_members(conv_id, &members, is_moderator)?;
    }

    // Change moderator settings
    if r.has_post_parameter("name") || r.has_post_parameter("canEveryoneAddMembers") {
        if !is_moderator {
            r.forbidden("You are not allowed to perform changes on this conversation!".to_string())?;
        }

        // Change conversation name
        if r.has_post_parameter("name") {
            let name = r.post_string_opt("name", 0, true)?;
            let name = if name.eq("false") || name.is_empty() {
                None
            } else {
                Some(remove_html_nodes(&name))
            };

            conversations_helper::set_name(conv_id, name)?;
        }


        // Change "canEveryoneAddMembers" parameter
        if r.has_post_parameter("canEveryoneAddMembers") {
            conversations_helper::set_can_everyone_add_members(
                conv_id, r.post_bool("canEveryoneAddMembers")?)?;
        }
    }

    r.success("Conversation information successfully updated!")
}

/// Find a private conversation
pub fn find_private(r: &mut HttpRequestHandler) -> RequestResult {
    let other_user = r.post_user_id("otherUser")?;
    let allow_create = r.post_bool_opt("allowCreate", false);

    // Query the database
    let mut list = conversations_helper::find_private(&r.user_id()?, &other_user)?;

    if list.is_empty() {
        if !allow_create {
            return r.not_found(format!("Not any private conversation was found. The server was not allowed to create a new one..."));
        }

        let new_conv = NewConversation {
            owner_id: r.user_id()?,
            name: None,
            owner_following: true,
            members: vec![r.user_id()?, other_user],
            can_everyone_add_members: true,
        };
        let conv_id = conversations_helper::create(&new_conv)?;
        list.push(conv_id);
    }

    r.set_response(ResFindPrivateConversations::new(list))
}

/// DEPRECATED : refresh current user conversations
///
/// This method was used only by ComunicWeb before the introduction of WebSockets
pub fn refresh_list(r: &mut HttpRequestHandler) -> RequestResult {
    let mut list = HashMap::new();

    // Check for new conversations
    if r.has_post_parameter("newConversations") {
        for conv_id in r.post_numbers_list("newConversations", 0)? {
            if !conversations_helper::does_user_belongs_to(&r.user_id()?, conv_id)? {
                r.forbidden(format!("Your do not belongs to conversation {} !", conv_id))?;
            }

            let list_conv = conversations_helper::get_last_messages(conv_id , 10)?;
            list.insert(conv_id as u64, list_conv);

            conversations_helper::mark_user_seen(conv_id as u64, &r.user_id()?)?;
        }
    }

    // Check for refresh of already initialized conversations
    if r.has_post_parameter("toRefresh") {
        let v: HashMap<String, HashMap<String, serde_json::Value>> =
            serde_json::from_str(r.post_string("toRefresh")?.as_str())?;

        for (k, v) in v {
            // Get conversation ID
            if !k.starts_with("conversation-") {
                return r.bad_request("Entries of 'toRefresh' must start with 'conversation-'!".to_string());
            }
            let conv_id = k.replace("conversation-", "").parse::<u64>()?;

            // Extract last message id
            if !v.contains_key("last_message_id") {
                return r.bad_request(format!("Missing 'last_message_id' in conversation {}!", conv_id));
            }
            let last_message_id = v["last_message_id"].as_u64().unwrap_or(0);

            // Check user rights
            if !conversations_helper::does_user_belongs_to(&r.user_id()?, conv_id)? {
                return r.forbidden(format!("You do not belong to conversation {}!", conv_id));
            }

            let list_conv = conversations_helper::get_new_messages(conv_id, last_message_id)?;
            list.insert(conv_id, list_conv);

            conversations_helper::mark_user_seen(conv_id as u64, &r.user_id()?)?;
        }
    }

    r.set_response(ConversationRefreshResultAPI::new(list))
}

/// Refresh a single conversation
pub fn refresh_single(r: &mut HttpRequestHandler) -> RequestResult {
    let conv_id = r.post_conv_id("conversationID")?;
    let last_message_id = r.post_u64("last_message_id")?;

    let messages = match last_message_id {
        // Get latest messages of the conversation
        0 => conversations_helper::get_last_messages(conv_id, 10)?,

        // Get new messages
        _ => conversations_helper::get_new_messages(conv_id, last_message_id)?,
    };

    conversations_helper::mark_user_seen(conv_id, &r.user_id()?)?;

    r.set_response(ConversationMessageAPI::for_list(&messages))
}

/// Get older messages of a conversation
pub fn get_older_messages(r: &mut HttpRequestHandler) -> RequestResult {
    let conv_id = r.post_conv_id("conversationID")?;
    let max_id = r.post_u64("oldest_message_id")? - 1;

    // Determine limit
    let limit = r.post_u64("limit")?;
    let limit = match limit {
        0 => 1,
        1..=60 => limit,
        _ => 60
    };

    let messages = conversations_helper::get_older_messages(conv_id, max_id, limit)?;

    r.set_response(ConversationMessageAPI::for_list(&messages))
}

/// Send a new message
pub fn send_message(r: &mut HttpRequestHandler) -> RequestResult {
    let conv_id = r.post_conv_id("conversationID")?;
    let message = r.post_string_without_html("message", 0, false)?;

    // Get image
    let image_path = match r.has_file("image") {
        false => None,
        true => Some(r.save_post_image("image", "conversations", 1200, 1200)?)
    };

    if image_path == None && message.len() < 3 {
        r.bad_request("Message is empty!".to_string())?;
    }

    conversations_helper::send_message(&NewConversationMessage {
        user_id: r.user_id()?,
        conv_id,
        message,
        image_path,
    })?;

    r.success("Conversation message was successfully sent!")
}

/// Count the number of unread conversation of the user
pub fn count_unread(r: &mut HttpRequestHandler) -> RequestResult {
    let num = conversations_helper::count_unread_for_user(&r.user_id()?)?;

    r.set_response(ResultCountUnreadConversations::new(num))
}

/// Get the list of unread conversations of a user
pub fn list_unread(r: &mut HttpRequestHandler) -> RequestResult {
    let list = conversations_helper::get_list_unread(&r.user_id()?)?;

    r.set_response(UnreadConversationAPI::for_list(&list))
}

/// Delete a conversation
pub fn delete_conversation(r: &mut HttpRequestHandler) -> RequestResult {
    let conv_id = r.post_conv_id("conversationID")?;

    conversations_helper::remove_user_from_conversation(&r.user_id()?, conv_id)?;

    r.success("The conversation has been deleted")
}

/// Update a single conversation message
pub fn update_message(r: &mut HttpRequestHandler) -> RequestResult {
    let msg_id = r.post_u64("messageID")?;
    let new_content = r.post_string_opt("content", 3, true)?;

    if !conversations_helper::is_message_owner(&r.user_id()?, msg_id)? {
        r.forbidden("You are not the owner of this message!".to_string())?;
    }

    conversations_helper::update_message_content(msg_id, &new_content)?;

    r.success("Conversation message content successfully updated")
}

/// Delete a conversation message
pub fn delete_message(r: &mut HttpRequestHandler) -> RequestResult {
    let msg_id = r.post_u64("messageID")?;

    if !conversations_helper::is_message_owner(&r.user_id()?, msg_id)? {
        r.forbidden("You are not the owner of this message!".to_string())?;
    }

    conversations_helper::delete_message_by_id(msg_id)?;

    r.success("The message has been successfully deleted!")
}