const { query, nonQuery } = require("../db-config/postgresql-common");

//Create User Info

async function updateUser(uid, mid) {
    try {      
        let exists = await query('SELECT row_to_json(username) FROM "User" As obj WHERE username = $1;', [uid]);

        //existiert
        if(exists != undefined) {
            await nonQuery('UPDATE "User" SET message_id = $1 WHERE username = $2', [mid, uid]);
        }

        //existiert nicht
        else {
            await nonQuery('INSERT INTO "User" (username, message_id) VALUES ($1, $2);', [uid, mid]);
        }
    }

    catch (error) {
        console.error(error);
    }
}

async function getmessageids(sl_id) {
    try {
        let members = query('SELECT * FROM "Shoppinglist_member" WHERE sl_id = $1;', [sl_id]);
        let admin = query('SELECT * FROM "Shoppinglist_admin" WHERE sl_id = $1;', [sl_id]);
        return users_to_array(admin, members);
        
    }

    catch(error) {

    }
}

//SELECT own shopping lists
async function getShoppinglistsAdmin(username) {
    try {
        
        let result = await query('SELECT row_to_json("Shoppinglist") AS obj FROM "Shoppinglist" JOIN "Shoppinglist_admin" USING (sl_id) WHERE \
        username = $1', [username]);

        return result;
    }

    catch (error) {
        console.error(error);
    }
}

//SELECT shared shopping lists

async function getShoppinglistsShared(username) {
    try {
        let result = await query('SELECT row_to_json("Shoppinglist") AS obj FROM "Shoppinglist" JOIN "Shoppinglist_member" USING (sl_id) WHERE \
        username = $1', [username]);
        console.log(result);
        return result;
    }

    catch (error) {
        console.error(error);
    }
}

//INSERT new Shoppinglist

async function newShoppinglist(name, description, username, color) {

    //generate sl_id

    let sl_id = generate_sl_id();

    //insert user if not exists

    try {
        await nonQuery('INSERT INTO "User" (username) VALUES ($1);', [username]);
    } 
    
    catch (error) {
        console.error(error);
    }

    //insert shoppinglist
    try {
        await nonQuery('INSERT INTO "Shoppinglist" (sl_id, name, description, color) VALUES ($1, $2, $3, $4);', [sl_id, name, description, color]);
    } 
    
    catch (error) {
        console.error(error);
    }

    //insert admin
    try {
        await nonQuery('INSERT INTO "Shoppinglist_admin" (username, sl_id) VALUES ($1, $2);', [username, sl_id]);
    }  
    
    catch (error) {
        console.error(error);
    }
}

//rename Shoppinglist


async function editShoppinglist(sl_id, newname, newdescription, newcolor) {
    try {
        let shoppinglist = await query('SELECT row_to_json("Shoppinglist") AS obj FROM "Shoppinglist" WHERE sl_id = $1;', [sl_id]);
        
        if(shoppinglist.name != newname && newname != undefined) {
            await nonQuery('UPDATE "Shoppinglist" SET name = $1 WHERE sl_id = $2;', [newname, sl_id]);
        }

        if(shoppinglist.description != newdescription && newdescription != undefined) {
            await nonQuery('UPDATE "Shoppinglist" SET description = $1 WHERE sl_id = $2;', [newdescription, sl_id]);
        }

        if(shoppinglist.color != newcolor && newcolor != undefined) {
            await nonQuery('UPDATE "Shoppinglist" SET color = $1 WHERE sl_id = $2;', [newcolor, sl_id]);
        }
    }

    catch (error) {
        console.error(error);
    }
}

async function generateUser() {
        //insert user

        try {
            await nonQuery('INSERT INTO "User" (username) VALUES ($1);', [username]);
        } 
        
        catch (error) {
            console.error(error);
        }
}

//get shoppinglist content
async function displayShoppinglist(sl_id, username) {
    try {
        let groups = await query('SELECT row_to_json("Group") AS obj FROM "Group" JOIN "Shoppinglist" USING (sl_id) WHERE sl_id = $1;', [sl_id]);
        let items = await query('SELECT row_to_json("Item") AS obj FROM "Item" JOIN "Group" USING (group_id) WHERE "Group".sl_id = $1;', [sl_id]);
        return items_in_groups(groups, items, sl_id);
    }

    catch (error) {
        console.error(error);
    }
}

//delete shoppinglist

async function deleteShoppinglist(sl_id) {

    try {
        await nonQuery('DELETE FROM "Shoppinglist_admin" WHERE sl_id = $1', [sl_id]);
        await nonQuery('DELETE FROM "Shoppinglist_member" WHERE sl_id = $1', [sl_id]);
        await nonQuery('DELETE FROM "Shoppinglist" WHERE sl_id = $1', [sl_id]);
    } 
    
    catch (error) {
        console.error(error);
    }
}

//add group into shoppinglist

async function addGroup(sl_id, name, color, hidden) {
    try {
        let grid = generate_group_id();
        await nonQuery('INSERT INTO "Group" (group_id, sl_id, name, color, hidden) VALUES ($1, $2, $3, $4, $5);', [grid, sl_id, name, color, hidden]);
    } 
    
    catch (error) {
        console.error(error);
    }
}

//add item into group

async function addItem(group_id, sl_id, name, count) {
    try {
        let itid = generate_item_id();
        await nonQuery('INSERT INTO "Item" VALUES ($1, $2, $3, $4, $5);', [itid, group_id, sl_id, name, count]);
    }

    catch (error) {
        console.error(error);
    }
}

//Edit Group
async function editGroup(sl_id, group_id, name, color, hidden) {
    try {
        let group  = await query('SELECT row_to_json("Group") AS obj FROM "Group" WHERE group_id = $1 AND sl_id = $2', [sl_id, group_id]);

        if(group.name != name && name != undefined) {
            await nonQuery('UPDATE "Group" SET name = $1 WHERE group_id = $2 AND sl_id = $3;', [name, group_id, sl_id]);
        }

        if(group.color != color && color != undefined) {
            await nonQuery('UPDATE "Group" SET color = $1 WHERE group_id = $2 AND sl_id = $3;', [color, group_id, sl_id]);
        }

        if(group.hidden != hidden && hidden != undefined) {
            await nonQuery('UPDATE "Group" SET hidden = $1 WHERE group_id = $2 AND sl_id = $3;', [hidden, group_id, sl_id]);
        }

    }

    catch (error) {
        console.error(error);
    }
}

//Edit Item

async function editItem(sl_id, group_id, item_id, name, count) {

    try {
        let item = query('SELECT row_to_json("Item") FROM "Item" WHERE item_id = $1 AND group_id = $2 AND sl_id = $3', [item_id, group_id, sl_id]);

        if(item.name != name && name != undefined) {
            await nonQuery('UPDATE "Item" SET name = $1 WHERE item_id = $2 AND group_id = $3 AND sl_id = $4', [name, item_id, group_id, sl_id]);
        }

        if(item.count != count && count != undefined) {
            await nonQuery('UPDATE "Item" SET count = $1 WHERE item_id = $2 AND group_id = $3 AND sl_id = $4', [count, item_id, group_id, sl_id]);
        }
    }

    catch (error) {
        console.error(error);
    }
}

//Delete Group

async function deleteGroup(group_id, sl_id) {
    try {
        //Alle Items der Group löschen
        nonQuery('DELETE FROM "Item" WHERE group_id = $1 AND sl_id = $2', [group_id, sl_id]);

        //Leere Gruppe löschen
        nonQuery('DELETE FROM "Group" WHERE group_id = $1 AND sl_id = $2', [group_id, sl_id]);
    }

    catch (error) {
        console.error(error);
    }
}

//Delete Item

async function deleteItem(item_id, group_id, sl_id) {
    try {
        nonQuery('DELETE FROM "Item" WHERE item_id = $1 AND group_id = $2 AND sl_id = $3;', [item_id, group_id, sl_id]);
    }

    catch(error) {
        console.error(error);
    }
}






// Invite System

async function verifyInvite(link, user_id) {
    try {
        let result = await query('SELECT row_to_json("Shoppinglist") AS obj FROM "Shoppinglist" WHERE invitelink = $1;', [link]);
        let sl_id = result[0].sl_id;
        await nonQuery('INSERT INTO "Shoppinglist_member" (username, sl_id) VALUES ($1, $2);', [user_id, sl_id]);
    }

    catch (error) {
        console.error(error);
    }
}

async function createInvite(sl_id) {
    try {
        let link = generateInviteLink();
        await nonQuery('UPDATE "Shoppinglist" SET invitelink = $1 WHERE sl_id = $2;', [link, sl_id]);
    }

    catch (error) {
        console.error(error);
    }
}

async function manInvite(sl_id, uid) {
    try {
        await nonQuery('INSERT INTO "Shoppinglist_member" (username, sl_id) VALUES ($1, $2);', [uid, sl_id]);
    }

    catch(error) {
        console.error(error);
    }
}








//sl_id generieren
function generate_sl_id() {
    var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
    var output = "";

    for(let i = 0; i < 8; i++) {
        output += possible.charAt(Math.floor(Math.random() * possible.length));
    }

    return output;
}

//group_id generieren
function generate_group_id() {
    var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
    var output = "";

    for(let i = 0; i < 8; i++) {
        output += possible.charAt(Math.floor(Math.random() * possible.length));
    }

    return output;
}

//item_id generieren
function generate_item_id() {
    var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
    var output = "";

    for(let i = 0; i < 8; i++) {
        output += possible.charAt(Math.floor(Math.random() * possible.length));
    }

    return output;
}

function items_in_groups(groups, items, sl_id) {

    let result = {
        sl_id: sl_id,
        groups: []
    };

    for(let item of groups) {

        result.groups.push({
            group_id: item.group_id,
            name: item.name,
            color: item.color,
            content: items.filter(function(obj) {return obj.group_id == item.group_id})
        });
    }

    return result;
}

//Create invite link for your own shoppinglist
function generateInviteLink() {
    var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
    var output = "";

    for(let i = 0; i < 50; i++) {
        output += possible.charAt(Math.floor(Math.random() * possible.length));
    }

    return output;
}

function users_to_array(admin, members) {
    let users = [];

    users.push(admin.username);

    for(let item of members) {
        users.push(item.username);
    }

    return users;
}

module.exports = {
    getShoppinglistsAdmin, getShoppinglistsShared, newShoppinglist, displayShoppinglist, deleteShoppinglist, addGroup,
    addItem, verifyInvite, createInvite, editShoppinglist, editGroup, editItem, deleteGroup, deleteItem, manInvite, updateUser
}