use chrono::{NaiveDateTime, Utc};
use serde_json::Value;

use crate::crypto;
use crate::CONFIG;

db_object! {
    #[derive(Identifiable, Queryable, Insertable, AsChangeset)]
    #[table_name = "users"]
    #[changeset_options(treat_none_as_null="true")]
    #[primary_key(uuid)]
    pub struct User {
        pub uuid: String,
        pub enabled: bool,
        pub created_at: NaiveDateTime,
        pub updated_at: NaiveDateTime,
        pub verified_at: Option<NaiveDateTime>,
        pub last_verifying_at: Option<NaiveDateTime>,
        pub login_verify_count: i32,

        pub email: String,
        pub email_new: Option<String>,
        pub email_new_token: Option<String>,
        pub name: String,

        pub password_hash: Vec<u8>,
        pub salt: Vec<u8>,
        pub password_iterations: i32,
        pub password_hint: Option<String>,

        pub akey: String,
        pub private_key: Option<String>,
        pub public_key: Option<String>,

        #[column_name = "totp_secret"] // Note, this is only added to the UserDb structs, not to User
        _totp_secret: Option<String>,
        pub totp_recover: Option<String>,

        pub security_stamp: String,
        pub stamp_exception: Option<String>,

        pub equivalent_domains: String,
        pub excluded_globals: String,

        pub client_kdf_type: i32,
        pub client_kdf_iter: i32,
    }


    #[derive(Identifiable, Queryable, Insertable)]
    #[table_name = "invitations"]
    #[primary_key(email)]
    pub struct Invitation {
        pub email: String,
    }
}

enum UserStatus {
    Enabled = 0,
    Invited = 1,
    _Disabled = 2,
}

#[derive(Serialize, Deserialize)]
pub struct UserStampException {
  pub route: String,
  pub security_stamp: String
}

/// Local methods
impl User {
    pub const CLIENT_KDF_TYPE_DEFAULT: i32 = 0; // PBKDF2: 0
    pub const CLIENT_KDF_ITER_DEFAULT: i32 = 100_000;

    pub fn new(mail: String) -> Self {
        let now = Utc::now().naive_utc();
        let email = mail.to_lowercase();

        Self {
            uuid: crate::util::get_uuid(),
            enabled: true,
            created_at: now,
            updated_at: now,
            verified_at: None,
            last_verifying_at: None,
            login_verify_count: 0,
            name: email.clone(),
            email,
            akey: String::new(),
            email_new: None,
            email_new_token: None,

            password_hash: Vec::new(),
            salt: crypto::get_random_64(),
            password_iterations: CONFIG.password_iterations(),

            security_stamp: crate::util::get_uuid(),
            stamp_exception: None,

            password_hint: None,
            private_key: None,
            public_key: None,

            _totp_secret: None,
            totp_recover: None,

            equivalent_domains: "[]".to_string(),
            excluded_globals: "[]".to_string(),

            client_kdf_type: Self::CLIENT_KDF_TYPE_DEFAULT,
            client_kdf_iter: Self::CLIENT_KDF_ITER_DEFAULT,
        }
    }

    pub fn check_valid_password(&self, password: &str) -> bool {
        crypto::verify_password_hash(
            password.as_bytes(),
            &self.salt,
            &self.password_hash,
            self.password_iterations as u32,
        )
    }

    pub fn check_valid_recovery_code(&self, recovery_code: &str) -> bool {
        if let Some(ref totp_recover) = self.totp_recover {
            crate::crypto::ct_eq(recovery_code, totp_recover.to_lowercase())
        } else {
            false
        }
    }

    /// Set the password hash generated
    /// And resets the security_stamp. Based upon the allow_next_route the security_stamp will be different.
    ///
    /// # Arguments
    ///
    /// * `password` - A str which contains a hashed version of the users master password.
    /// * `allow_next_route` - A Option<&str> with the function name of the next allowed (rocket) route.
    ///
    pub fn set_password(&mut self, password: &str, allow_next_route: Option<&str>) {
        self.password_hash = crypto::hash_password(password.as_bytes(), &self.salt, self.password_iterations as u32);

        if let Some(route) = allow_next_route {
            self.set_stamp_exception(route);
        }

        self.reset_security_stamp()
    }

    pub fn reset_security_stamp(&mut self) {
        self.security_stamp = crate::util::get_uuid();
    }

    /// Set the stamp_exception to only allow a subsequent request matching a specific route using the current security-stamp.
    ///
    /// # Arguments
    /// * `route_exception` - A str with the function name of the next allowed (rocket) route.
    ///
    /// ### Future
    /// In the future it could be posible that we need more of these exception routes.
    /// In that case we could use an Vec<UserStampException> and add multiple exceptions.
    pub fn set_stamp_exception(&mut self, route_exception: &str) {
        let stamp_exception = UserStampException {
            route: route_exception.to_string(),
            security_stamp: self.security_stamp.to_string()
        };
        self.stamp_exception = Some(serde_json::to_string(&stamp_exception).unwrap_or_default());
    }

    /// Resets the stamp_exception to prevent re-use of the previous security-stamp
    ///
    /// ### Future
    /// In the future it could be posible that we need more of these exception routes.
    /// In that case we could use an Vec<UserStampException> and add multiple exceptions.
    pub fn reset_stamp_exception(&mut self) {
        self.stamp_exception = None;
    }
}

use super::{Cipher, Device, Favorite, Folder, Send, TwoFactor, UserOrgType, UserOrganization};
use crate::db::DbConn;

use crate::api::EmptyResult;
use crate::error::MapResult;

/// Database methods
impl User {
    pub fn to_json(&self, conn: &DbConn) -> Value {
        let orgs = UserOrganization::find_by_user(&self.uuid, conn);
        let orgs_json: Vec<Value> = orgs.iter().map(|c| c.to_json(&conn)).collect();
        let twofactor_enabled = !TwoFactor::find_by_user(&self.uuid, conn).is_empty();

        // TODO: Might want to save the status field in the DB
        let status = if self.password_hash.is_empty() {
            UserStatus::Invited
        } else {
            UserStatus::Enabled
        };

        json!({
            "_Status": status as i32,
            "Id": self.uuid,
            "Name": self.name,
            "Email": self.email,
            "EmailVerified": !CONFIG.mail_enabled() || self.verified_at.is_some(),
            "Premium": true,
            "MasterPasswordHint": self.password_hint,
            "Culture": "en-US",
            "TwoFactorEnabled": twofactor_enabled,
            "Key": self.akey,
            "PrivateKey": self.private_key,
            "SecurityStamp": self.security_stamp,
            "Organizations": orgs_json,
            "Object": "profile"
        })
    }

    pub fn save(&mut self, conn: &DbConn) -> EmptyResult {
        if self.email.trim().is_empty() {
            err!("User email can't be empty")
        }

        self.updated_at = Utc::now().naive_utc();

        db_run! {conn:
            sqlite, mysql {
                match diesel::replace_into(users::table)
                    .values(UserDb::to_db(self))
                    .execute(conn)
                {
                    Ok(_) => Ok(()),
                    // Record already exists and causes a Foreign Key Violation because replace_into() wants to delete the record first.
                    Err(diesel::result::Error::DatabaseError(diesel::result::DatabaseErrorKind::ForeignKeyViolation, _)) => {
                        diesel::update(users::table)
                            .filter(users::uuid.eq(&self.uuid))
                            .set(UserDb::to_db(self))
                            .execute(conn)
                            .map_res("Error saving user")
                    }
                    Err(e) => Err(e.into()),
                }.map_res("Error saving user")
            }
            postgresql {
                let value = UserDb::to_db(self);
                diesel::insert_into(users::table) // Insert or update
                    .values(&value)
                    .on_conflict(users::uuid)
                    .do_update()
                    .set(&value)
                    .execute(conn)
                    .map_res("Error saving user")
            }
        }
    }

    pub fn delete(self, conn: &DbConn) -> EmptyResult {
        for user_org in UserOrganization::find_by_user(&self.uuid, conn) {
            if user_org.atype == UserOrgType::Owner {
                let owner_type = UserOrgType::Owner as i32;
                if UserOrganization::find_by_org_and_type(&user_org.org_uuid, owner_type, conn).len() <= 1 {
                    err!("Can't delete last owner")
                }
            }
        }

        Send::delete_all_by_user(&self.uuid, conn)?;
        UserOrganization::delete_all_by_user(&self.uuid, conn)?;
        Cipher::delete_all_by_user(&self.uuid, conn)?;
        Favorite::delete_all_by_user(&self.uuid, conn)?;
        Folder::delete_all_by_user(&self.uuid, conn)?;
        Device::delete_all_by_user(&self.uuid, conn)?;
        TwoFactor::delete_all_by_user(&self.uuid, conn)?;
        Invitation::take(&self.email, conn); // Delete invitation if any

        db_run! {conn: {
            diesel::delete(users::table.filter(users::uuid.eq(self.uuid)))
                .execute(conn)
                .map_res("Error deleting user")
        }}
    }

    pub fn update_uuid_revision(uuid: &str, conn: &DbConn) {
        if let Err(e) = Self::_update_revision(uuid, &Utc::now().naive_utc(), conn) {
            warn!("Failed to update revision for {}: {:#?}", uuid, e);
        }
    }

    pub fn update_all_revisions(conn: &DbConn) -> EmptyResult {
        let updated_at = Utc::now().naive_utc();

        db_run! {conn: {
            crate::util::retry(|| {
                diesel::update(users::table)
                    .set(users::updated_at.eq(updated_at))
                    .execute(conn)
            }, 10)
            .map_res("Error updating revision date for all users")
        }}
    }

    pub fn update_revision(&mut self, conn: &DbConn) -> EmptyResult {
        self.updated_at = Utc::now().naive_utc();

        Self::_update_revision(&self.uuid, &self.updated_at, conn)
    }

    fn _update_revision(uuid: &str, date: &NaiveDateTime, conn: &DbConn) -> EmptyResult {
        db_run! {conn: {
            crate::util::retry(|| {
                diesel::update(users::table.filter(users::uuid.eq(uuid)))
                    .set(users::updated_at.eq(date))
                    .execute(conn)
            }, 10)
            .map_res("Error updating user revision")
        }}
    }

    pub fn find_by_mail(mail: &str, conn: &DbConn) -> Option<Self> {
        let lower_mail = mail.to_lowercase();
        db_run! {conn: {
            users::table
                .filter(users::email.eq(lower_mail))
                .first::<UserDb>(conn)
                .ok()
                .from_db()
        }}
    }

    pub fn find_by_uuid(uuid: &str, conn: &DbConn) -> Option<Self> {
        db_run! {conn: {
            users::table.filter(users::uuid.eq(uuid)).first::<UserDb>(conn).ok().from_db()
        }}
    }

    pub fn get_all(conn: &DbConn) -> Vec<Self> {
        db_run! {conn: {
            users::table.load::<UserDb>(conn).expect("Error loading users").from_db()
        }}
    }

    pub fn last_active(&self, conn: &DbConn) -> Option<NaiveDateTime> {
        match Device::find_latest_active_by_user(&self.uuid, conn) {
            Some(device) => Some(device.updated_at),
            None => None
        }
    }
}

impl Invitation {
    pub const fn new(email: String) -> Self {
        Self { email }
    }

    pub fn save(&self, conn: &DbConn) -> EmptyResult {
        if self.email.trim().is_empty() {
            err!("Invitation email can't be empty")
        }

        db_run! {conn:
            sqlite, mysql {
                // Not checking for ForeignKey Constraints here
                // Table invitations does not have any ForeignKey Constraints.
                diesel::replace_into(invitations::table)
                    .values(InvitationDb::to_db(self))
                    .execute(conn)
                    .map_res("Error saving invitation")
            }
            postgresql {
                diesel::insert_into(invitations::table)
                    .values(InvitationDb::to_db(self))
                    .on_conflict(invitations::email)
                    .do_nothing()
                    .execute(conn)
                    .map_res("Error saving invitation")
            }
        }
    }

    pub fn delete(self, conn: &DbConn) -> EmptyResult {
        db_run! {conn: {
            diesel::delete(invitations::table.filter(invitations::email.eq(self.email)))
                .execute(conn)
                .map_res("Error deleting invitation")
        }}
    }

    pub fn find_by_mail(mail: &str, conn: &DbConn) -> Option<Self> {
        let lower_mail = mail.to_lowercase();
        db_run! {conn: {
            invitations::table
                .filter(invitations::email.eq(lower_mail))
                .first::<InvitationDb>(conn)
                .ok()
                .from_db()
        }}
    }

    pub fn take(mail: &str, conn: &DbConn) -> bool {
        match Self::find_by_mail(mail, &conn) {
            Some(invitation) => invitation.delete(&conn).is_ok(),
            None => false,
        }
    }
}