use super::ChangeOperation;
use crate::BEGIN_IMMEDIATE;
use async_trait::async_trait;
use derive_more::derive::Constructor;
use ical::parser::ParserError;
use rustical_ical::AddressObject;
use rustical_store::{
    Addressbook, AddressbookStore, CollectionMetadata, CollectionOperation,
    CollectionOperationInfo, Error, synctoken::format_synctoken,
};
use sqlx::{Acquire, Executor, Sqlite, SqlitePool, Transaction};
use tokio::sync::mpsc::Sender;
use tracing::{error, error_span, instrument, warn};

pub mod birthday_calendar;

#[derive(Debug, Clone)]
struct AddressObjectRow {
    id: String,
    vcf: String,
}
impl From<AddressObjectRow> for (String, Result<AddressObject, ParserError>) {
    fn from(row: AddressObjectRow) -> Self {
        let result = AddressObject::from_vcf(row.vcf);
        (row.id, result)
    }
}

impl TryFrom<AddressObjectRow> for (String, AddressObject) {
    type Error = rustical_store::Error;

    fn try_from(value: AddressObjectRow) -> Result<Self, Self::Error> {
        Ok((value.id, AddressObject::from_vcf(value.vcf)?))
    }
}

#[derive(Debug, Clone, Constructor)]
pub struct SqliteAddressbookStore {
    db: SqlitePool,
    sender: Sender<CollectionOperation>,
    skip_broken: bool,
}

impl SqliteAddressbookStore {
    // Commit "orphaned" objects to the changelog table
    pub async fn repair_orphans(&self) -> Result<(), Error> {
        struct Row {
            principal: String,
            addressbook_id: String,
            id: String,
            deleted: bool,
        }

        let mut tx = self
            .db
            .begin_with(BEGIN_IMMEDIATE)
            .await
            .map_err(crate::Error::from)?;

        let rows = sqlx::query_as!(
            Row,
            r#"
                SELECT principal, addressbook_id, id, (deleted_at IS NOT NULL) AS "deleted: bool"
                    FROM addressobjects
                    WHERE (principal, addressbook_id, id) NOT IN (
                        SELECT DISTINCT principal, addressbook_id, object_id FROM addressobjectchangelog
                    )
                ;
                "#,
        )
        .fetch_all(&mut *tx)
        .await
        .map_err(crate::Error::from)?;

        for row in rows {
            let operation = if row.deleted {
                ChangeOperation::Delete
            } else {
                ChangeOperation::Add
            };
            warn!(
                "Commiting orphaned addressbook object ({},{},{}), deleted={}",
                &row.principal, &row.addressbook_id, &row.id, &row.deleted
            );
            Self::log_object_operation(
                &mut tx,
                &row.principal,
                &row.addressbook_id,
                &row.id,
                operation,
            )
            .await?;
        }
        tx.commit().await.map_err(crate::Error::from)?;

        Ok(())
    }

    #[allow(clippy::missing_panics_doc)]
    pub async fn validate_objects(&self, principal: &str) -> Result<(), Error> {
        let mut success = true;
        for addressbook in self.get_addressbooks(principal).await? {
            for (object_id, res) in Self::_get_objects(&self.db, principal, &addressbook.id).await?
            {
                if let Err(err) = res {
                    warn!(
                        "Invalid address object found at {principal}/{addr_id}/{object_id}.vcf. Error: {err}",
                        addr_id = addressbook.id
                    );
                    success = false;
                }
            }
        }
        if !success {
            if self.skip_broken {
                error!(
                    "Not all address objects are valid. Since data_store.sqlite.skip_broken=true they will be hidden. You are still advised to manually remove or repair the object. If you need help feel free to open up an issue on GitHub."
                );
            } else {
                error!(
                    "Not all address objects are valid. Since data_store.sqlite.skip_broken=false this causes a panic. Remove or repair the broken objects manually or set data_store.sqlite.skip_broken=false as a temporary solution to ignore the error. If you need help feel free to open up an issue on GitHub."
                );
                panic!();
            }
        }
        Ok(())
    }

    // Logs an operation to an address object
    async fn log_object_operation(
        tx: &mut Transaction<'_, Sqlite>,
        principal: &str,
        addressbook_id: &str,
        object_id: &str,
        operation: ChangeOperation,
    ) -> Result<String, Error> {
        struct Synctoken {
            synctoken: i64,
        }
        let Synctoken { synctoken } = sqlx::query_as!(
            Synctoken,
            r#"
        UPDATE addressbooks
        SET synctoken = synctoken + 1
        WHERE (principal, id) = (?1, ?2)
        RETURNING synctoken"#,
            principal,
            addressbook_id
        )
        .fetch_one(&mut **tx)
        .await
        .map_err(crate::Error::from)?;

        sqlx::query!(
        r#"
        INSERT INTO addressobjectchangelog (principal, addressbook_id, object_id, "operation", synctoken)
        VALUES (?1, ?2, ?3, ?4, (
            SELECT synctoken FROM addressbooks WHERE (principal, id) = (?1, ?2)
        ))"#,
        principal,
        addressbook_id,
        object_id,
        operation
    )
    .execute(&mut **tx)
    .await
    .map_err(crate::Error::from)?;
        Ok(format_synctoken(synctoken))
    }

    fn send_push_notification(&self, data: CollectionOperationInfo, topic: String) {
        if let Err(err) = self.sender.try_send(CollectionOperation { topic, data }) {
            error_span!(
                "Error trying to send addressbook update notification:",
                err = format!("{err}"),
            );
        }
    }

    async fn _get_addressbook<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        principal: &str,
        id: &str,
        show_deleted: bool,
    ) -> Result<Addressbook, rustical_store::Error> {
        let addressbook = sqlx::query_as!(
            Addressbook,
            r#"SELECT principal, id, synctoken, displayname, description, deleted_at, push_topic
                FROM addressbooks
                WHERE (principal, id) = (?, ?)
                AND ((deleted_at IS NULL) OR ?) "#,
            principal,
            id,
            show_deleted
        )
        .fetch_one(executor)
        .await
        .map_err(crate::Error::from)?;
        Ok(addressbook)
    }

    async fn _get_addressbooks<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        principal: &str,
    ) -> Result<Vec<Addressbook>, rustical_store::Error> {
        let addressbooks = sqlx::query_as!(
            Addressbook,
            r#"SELECT principal, id, synctoken, displayname, description, deleted_at, push_topic
                FROM addressbooks
                WHERE principal = ? AND deleted_at IS NULL"#,
            principal
        )
        .fetch_all(executor)
        .await
        .map_err(crate::Error::from)?;
        Ok(addressbooks)
    }

    async fn _get_deleted_addressbooks<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        principal: &str,
    ) -> Result<Vec<Addressbook>, rustical_store::Error> {
        let addressbooks = sqlx::query_as!(
            Addressbook,
            r#"SELECT principal, id, synctoken, displayname, description, deleted_at, push_topic
                FROM addressbooks
                WHERE principal = ? AND deleted_at IS NOT NULL"#,
            principal
        )
        .fetch_all(executor)
        .await
        .map_err(crate::Error::from)?;
        Ok(addressbooks)
    }

    async fn _update_addressbook<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        principal: &str,
        id: &str,
        addressbook: &Addressbook,
    ) -> Result<(), rustical_store::Error> {
        let result = sqlx::query!(
            r#"UPDATE addressbooks SET principal = ?, id = ?, displayname = ?, description = ?, push_topic = ?
                WHERE (principal, id) = (?, ?)"#,
            addressbook.principal,
            addressbook.id,
            addressbook.displayname,
            addressbook.description,
            addressbook.push_topic,
            principal,
            id
        )
        .execute(executor)
        .await
        .map_err(crate::Error::from)?;
        if result.rows_affected() == 0 {
            return Err(rustical_store::Error::NotFound);
        }
        Ok(())
    }

    async fn _insert_addressbook<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        addressbook: &Addressbook,
    ) -> Result<(), rustical_store::Error> {
        sqlx::query!(
            r#"INSERT INTO addressbooks (principal, id, displayname, description, push_topic)
                VALUES (?, ?, ?, ?, ?)"#,
            addressbook.principal,
            addressbook.id,
            addressbook.displayname,
            addressbook.description,
            addressbook.push_topic,
        )
        .execute(executor)
        .await
        .map_err(crate::Error::from)?;
        Ok(())
    }

    async fn _delete_addressbook<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        principal: &str,
        addressbook_id: &str,
        use_trashbin: bool,
    ) -> Result<(), rustical_store::Error> {
        if use_trashbin {
            sqlx::query!(
                r#"UPDATE addressbooks SET deleted_at = datetime() WHERE (principal, id) = (?, ?)"#,
                principal,
                addressbook_id
            )
            .execute(executor)
            .await
            .map_err(crate::Error::from)?;
        } else {
            sqlx::query!(
                r#"DELETE FROM addressbooks WHERE (principal, id) = (?, ?)"#,
                principal,
                addressbook_id
            )
            .execute(executor)
            .await
            .map_err(crate::Error::from)?;
        }

        Ok(())
    }

    async fn _restore_addressbook<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        principal: &str,
        addressbook_id: &str,
    ) -> Result<(), rustical_store::Error> {
        sqlx::query!(
            r"UPDATE addressbooks SET deleted_at = NULL WHERE (principal, id) = (?, ?)",
            principal,
            addressbook_id
        )
        .execute(executor)
        .await
        .map_err(crate::Error::from)?;
        Ok(())
    }

    async fn _sync_changes<'a, A: Acquire<'a, Database = Sqlite>>(
        acquire: A,
        principal: &str,
        addressbook_id: &str,
        synctoken: i64,
    ) -> Result<(Vec<(String, AddressObject)>, Vec<String>, i64), rustical_store::Error> {
        struct Row {
            object_id: String,
            synctoken: i64,
        }

        let mut conn = acquire.acquire().await.map_err(crate::Error::from)?;

        let changes = sqlx::query_as!(
            Row,
            r#"
                SELECT DISTINCT object_id, max(0, synctoken) as "synctoken!: i64" from addressobjectchangelog
                WHERE synctoken > ?
                ORDER BY synctoken ASC
            "#,
            synctoken
        )
        .fetch_all(&mut *conn)
        .await.map_err(crate::Error::from)?;

        let mut objects = vec![];
        let mut deleted_objects = vec![];

        let new_synctoken = changes.last().map_or(0, |&Row { synctoken, .. }| synctoken);

        for Row { object_id, .. } in changes {
            match Self::_get_object(&mut *conn, principal, addressbook_id, &object_id, false).await
            {
                Ok(object) => objects.push((object_id, object)),
                Err(rustical_store::Error::NotFound) => deleted_objects.push(object_id),
                Err(err) => return Err(err),
            }
        }

        Ok((objects, deleted_objects, new_synctoken))
    }

    async fn _list_objects<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        principal: &str,
        addressbook_id: &str,
    ) -> Result<Vec<(u64, bool)>, rustical_store::Error> {
        struct ObjectEntry {
            length: u64,
            deleted: bool,
        }
        Ok(sqlx::query_as!(
            ObjectEntry,
            "SELECT length(vcf) AS 'length!: u64', deleted_at AS 'deleted!: bool' FROM addressobjects WHERE principal = ? AND addressbook_id = ?",
            principal,
            addressbook_id
        )
        .fetch_all(executor)
        .await.map_err(crate::Error::from)?
        .into_iter()
        .map(|row| (row.length, row.deleted))
        .collect())
    }

    async fn _get_objects<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        principal: &str,
        addressbook_id: &str,
    ) -> Result<impl Iterator<Item = (String, Result<AddressObject, ParserError>)>, Error> {
        Ok(sqlx::query_as!(
            AddressObjectRow,
            "SELECT id, vcf FROM addressobjects WHERE principal = ? AND addressbook_id = ? AND deleted_at IS NULL",
            principal,
            addressbook_id
        )
        .fetch_all(executor)
        .await.map_err(crate::Error::from)?
        .into_iter()
        .map(Into::into)
        )
    }

    async fn _get_object<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        principal: &str,
        addressbook_id: &str,
        object_id: &str,
        show_deleted: bool,
    ) -> Result<AddressObject, rustical_store::Error> {
        let (id, object) = sqlx::query_as!(
            AddressObjectRow,
            "SELECT id, vcf FROM addressobjects WHERE (principal, addressbook_id, id) = (?, ?, ?) AND ((deleted_at IS NULL) OR ?)",
            principal,
            addressbook_id,
            object_id,
            show_deleted
        )
        .fetch_one(executor)
        .await
        .map_err(crate::Error::from)?
        .try_into()?;
        assert_eq!(id, object_id);
        Ok(object)
    }

    async fn _put_object<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        principal: &str,
        addressbook_id: &str,
        object_id: &str,
        object: &AddressObject,
        overwrite: bool,
    ) -> Result<(), rustical_store::Error> {
        let vcf = object.get_vcf();

        (if overwrite {
            sqlx::query!(
            "REPLACE INTO addressobjects (principal, addressbook_id, id, vcf) VALUES (?, ?, ?, ?)",
            principal,
            addressbook_id,
            object_id,
            vcf
        )
        } else {
            // If the object already exists a database error is thrown and handled in error.rs
            sqlx::query!(
            "INSERT INTO addressobjects (principal, addressbook_id, id, vcf) VALUES (?, ?, ?, ?)",
            principal,
            addressbook_id,
            object_id,
            vcf
        )
        })
        .execute(executor)
        .await
        .map_err(crate::Error::from)?;

        Ok(())
    }

    async fn _delete_object<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        principal: &str,
        addressbook_id: &str,
        object_id: &str,
        use_trashbin: bool,
    ) -> Result<(), rustical_store::Error> {
        if use_trashbin {
            sqlx::query!(
                "UPDATE addressobjects SET deleted_at = datetime(), updated_at = datetime() WHERE (principal, addressbook_id, id) = (?, ?, ?)",
                principal,
                addressbook_id,
                object_id
            )
            .execute(executor)
            .await.map_err(crate::Error::from)?;
        } else {
            sqlx::query!(
                "DELETE FROM addressobjects WHERE addressbook_id = ? AND id = ?",
                addressbook_id,
                object_id
            )
            .execute(executor)
            .await
            .map_err(crate::Error::from)?;
        }
        Ok(())
    }

    async fn _restore_object<'e, E: Executor<'e, Database = Sqlite>>(
        executor: E,
        principal: &str,
        addressbook_id: &str,
        object_id: &str,
    ) -> Result<(), rustical_store::Error> {
        sqlx::query!(
            r#"UPDATE addressobjects SET deleted_at = NULL, updated_at = datetime() WHERE (principal, addressbook_id, id) = (?, ?, ?)"#,
            principal,
            addressbook_id,
            object_id
        )
        .execute(executor)
        .await.map_err(crate::Error::from)?;
        Ok(())
    }
}

#[async_trait]
impl AddressbookStore for SqliteAddressbookStore {
    #[instrument]
    async fn get_addressbook(
        &self,
        principal: &str,
        id: &str,
        show_deleted: bool,
    ) -> Result<Addressbook, rustical_store::Error> {
        Self::_get_addressbook(&self.db, principal, id, show_deleted).await
    }

    #[instrument]
    async fn get_addressbooks(
        &self,
        principal: &str,
    ) -> Result<Vec<Addressbook>, rustical_store::Error> {
        Self::_get_addressbooks(&self.db, principal).await
    }

    #[instrument]
    async fn get_deleted_addressbooks(
        &self,
        principal: &str,
    ) -> Result<Vec<Addressbook>, rustical_store::Error> {
        Self::_get_deleted_addressbooks(&self.db, principal).await
    }

    #[instrument]
    async fn update_addressbook(
        &self,
        principal: &str,
        id: &str,
        addressbook: Addressbook,
    ) -> Result<(), rustical_store::Error> {
        assert_eq!(principal, &addressbook.principal);
        assert_eq!(id, &addressbook.id);
        Self::_update_addressbook(&self.db, principal, id, &addressbook).await
    }

    #[instrument]
    async fn insert_addressbook(
        &self,
        addressbook: Addressbook,
    ) -> Result<(), rustical_store::Error> {
        let mut tx = self
            .db
            .begin_with(BEGIN_IMMEDIATE)
            .await
            .map_err(crate::Error::from)?;
        Self::_insert_addressbook(&mut *tx, &addressbook).await?;
        let birthday_cal = Self::default_birthday_calendar(addressbook);
        Self::_insert_birthday_calendar(&mut *tx, &birthday_cal).await?;
        tx.commit().await.map_err(crate::Error::from)?;
        Ok(())
    }

    #[instrument]
    async fn delete_addressbook(
        &self,
        principal: &str,
        addressbook_id: &str,
        use_trashbin: bool,
    ) -> Result<(), rustical_store::Error> {
        let mut tx = self
            .db
            .begin_with(BEGIN_IMMEDIATE)
            .await
            .map_err(crate::Error::from)?;

        let addressbook =
            match Self::_get_addressbook(&mut *tx, principal, addressbook_id, use_trashbin).await {
                Ok(addressbook) => Some(addressbook),
                Err(Error::NotFound) => None,
                Err(err) => return Err(err),
            };

        Self::_delete_addressbook(&mut *tx, principal, addressbook_id, use_trashbin).await?;
        tx.commit().await.map_err(crate::Error::from)?;

        if let Some(addressbook) = addressbook {
            self.send_push_notification(CollectionOperationInfo::Delete, addressbook.push_topic);
        }

        Ok(())
    }

    #[instrument]
    async fn restore_addressbook(
        &self,
        principal: &str,
        addressbook_id: &str,
    ) -> Result<(), rustical_store::Error> {
        Self::_restore_addressbook(&self.db, principal, addressbook_id).await
    }

    #[instrument]
    async fn sync_changes(
        &self,
        principal: &str,
        addressbook_id: &str,
        synctoken: i64,
    ) -> Result<(Vec<(String, AddressObject)>, Vec<String>, i64), rustical_store::Error> {
        Self::_sync_changes(&self.db, principal, addressbook_id, synctoken).await
    }

    #[instrument]
    async fn addressbook_metadata(
        &self,
        principal: &str,
        addressbook_id: &str,
    ) -> Result<CollectionMetadata, rustical_store::Error> {
        let mut sizes = vec![];
        let mut deleted_sizes = vec![];
        for (size, deleted) in Self::_list_objects(&self.db, principal, addressbook_id).await? {
            if deleted {
                deleted_sizes.push(size);
            } else {
                sizes.push(size);
            }
        }
        Ok(CollectionMetadata {
            len: sizes.len(),
            deleted_len: deleted_sizes.len(),
            size: sizes.iter().sum(),
            deleted_size: deleted_sizes.iter().sum(),
        })
    }

    #[instrument]
    async fn get_objects(
        &self,
        principal: &str,
        addressbook_id: &str,
    ) -> Result<Vec<(String, AddressObject)>, rustical_store::Error> {
        let objects = Self::_get_objects(&self.db, principal, addressbook_id).await?;
        if self.skip_broken {
            Ok(objects
                .filter_map(|(id, res)| Some((id, res.ok()?)))
                .collect())
        } else {
            Ok(objects
                .map(|(id, res)| res.map(|obj| (id, obj)))
                .collect::<Result<Vec<_>, _>>()?)
        }
    }

    #[instrument]
    async fn get_object(
        &self,
        principal: &str,
        addressbook_id: &str,
        object_id: &str,
        show_deleted: bool,
    ) -> Result<AddressObject, rustical_store::Error> {
        Self::_get_object(&self.db, principal, addressbook_id, object_id, show_deleted).await
    }

    #[instrument]
    async fn put_object(
        &self,
        principal: &str,
        addressbook_id: &str,
        object_id: &str,
        object: AddressObject,
        overwrite: bool,
    ) -> Result<(), rustical_store::Error> {
        let mut tx = self
            .db
            .begin_with(BEGIN_IMMEDIATE)
            .await
            .map_err(crate::Error::from)?;

        Self::_put_object(
            &mut *tx,
            principal,
            addressbook_id,
            object_id,
            &object,
            overwrite,
        )
        .await?;

        let sync_token = Self::log_object_operation(
            &mut tx,
            principal,
            addressbook_id,
            object_id,
            ChangeOperation::Add,
        )
        .await
        .map_err(crate::Error::from)?;

        tx.commit().await.map_err(crate::Error::from)?;

        self.send_push_notification(
            CollectionOperationInfo::Content { sync_token },
            self.get_addressbook(principal, addressbook_id, false)
                .await?
                .push_topic,
        );

        Ok(())
    }

    #[instrument]
    async fn delete_object(
        &self,
        principal: &str,
        addressbook_id: &str,
        object_id: &str,
        use_trashbin: bool,
    ) -> Result<(), rustical_store::Error> {
        let mut tx = self
            .db
            .begin_with(BEGIN_IMMEDIATE)
            .await
            .map_err(crate::Error::from)?;

        Self::_delete_object(&mut *tx, principal, addressbook_id, object_id, use_trashbin).await?;

        let sync_token = Self::log_object_operation(
            &mut tx,
            principal,
            addressbook_id,
            object_id,
            ChangeOperation::Delete,
        )
        .await
        .map_err(crate::Error::from)?;

        tx.commit().await.map_err(crate::Error::from)?;

        self.send_push_notification(
            CollectionOperationInfo::Content { sync_token },
            self.get_addressbook(principal, addressbook_id, false)
                .await?
                .push_topic,
        );
        Ok(())
    }

    #[instrument]
    async fn restore_object(
        &self,
        principal: &str,
        addressbook_id: &str,
        object_id: &str,
    ) -> Result<(), rustical_store::Error> {
        let mut tx = self
            .db
            .begin_with(BEGIN_IMMEDIATE)
            .await
            .map_err(crate::Error::from)?;

        Self::_restore_object(&mut *tx, principal, addressbook_id, object_id).await?;

        let sync_token = Self::log_object_operation(
            &mut tx,
            principal,
            addressbook_id,
            object_id,
            ChangeOperation::Add,
        )
        .await
        .map_err(crate::Error::from)?;
        tx.commit().await.map_err(crate::Error::from)?;

        self.send_push_notification(
            CollectionOperationInfo::Content { sync_token },
            self.get_addressbook(principal, addressbook_id, false)
                .await?
                .push_topic,
        );

        Ok(())
    }

    #[instrument(skip(objects))]
    async fn import_addressbook(
        &self,
        addressbook: Addressbook,
        objects: Vec<(String, AddressObject)>,
        merge_existing: bool,
    ) -> Result<(), Error> {
        let mut tx = self
            .db
            .begin_with(BEGIN_IMMEDIATE)
            .await
            .map_err(crate::Error::from)?;

        let existing =
            match Self::_get_addressbook(&mut *tx, &addressbook.principal, &addressbook.id, true)
                .await
            {
                Ok(addressbook) => Some(addressbook),
                Err(Error::NotFound) => None,
                Err(err) => return Err(err),
            };
        if existing.is_some() && !merge_existing {
            return Err(Error::AlreadyExists);
        }
        if existing.is_none() {
            Self::_insert_addressbook(&mut *tx, &addressbook).await?;
        }

        let mut sync_token = None;
        for (object_id, object) in objects {
            Self::_put_object(
                &mut *tx,
                &addressbook.principal,
                &addressbook.id,
                &object_id,
                &object,
                false,
            )
            .await?;

            sync_token = Some(
                Self::log_object_operation(
                    &mut tx,
                    &addressbook.principal,
                    &addressbook.id,
                    &object_id,
                    ChangeOperation::Add,
                )
                .await?,
            );
        }

        tx.commit().await.map_err(crate::Error::from)?;
        if let Some(sync_token) = sync_token {
            self.send_push_notification(
                CollectionOperationInfo::Content { sync_token },
                self.get_addressbook(&addressbook.principal, &addressbook.id, true)
                    .await?
                    .push_topic,
            );
        }
        Ok(())
    }
}