#![macro_use]

#[macro_use]
mod macros;

pub mod constants;
pub mod entry;
pub mod inner;
pub mod lang;

use crate::addressing::Address;
use crate::database::constants::{
    IS_OF_TYPE_ATTR, TYPE_ADDR, TYPE_ID_ATTR, TYPE_INVARIANT, TYPE_IS_ATTR,
};
use crate::database::entry::{Entry, EntryValue};
use crate::database::inner::models;
use crate::database::inner::schema::data;
use crate::database::lang::Query;
use crate::util::hash::{Hash, Hashable};
use crate::util::LoggerSink;
use anyhow::{anyhow, Result};
use diesel::debug_query;
use diesel::prelude::*;
use diesel::r2d2::{self, ConnectionManager};
use diesel::result::{DatabaseErrorKind, Error};
use diesel::sqlite::{Sqlite, SqliteConnection};
use log::{debug, trace};
use std::convert::TryFrom;
use std::fs;
use std::path::{Path, PathBuf};
use std::time::Duration;

pub fn insert_file<C: Connection<Backend = Sqlite>>(
    connection: &C,
    file: models::NewFile,
) -> Result<usize> {
    use crate::database::inner::schema::files;

    debug!(
        "Inserting {} ({})...",
        &file.path,
        Address::Hash(Hash((&file.hash).clone()))
    );

    Ok(diesel::insert_into(files::table)
        .values(file)
        .execute(connection)?)
}

pub fn retrieve_file<C: Connection<Backend = Sqlite>>(
    connection: &C,
    obj_hash: Hash,
) -> Result<Vec<models::File>> {
    use crate::database::inner::schema::files::dsl::*;

    let matches = files
        .filter(valid.eq(true))
        .filter(hash.eq(obj_hash.0))
        .load::<models::File>(connection)?;

    Ok(matches)
}

pub fn retrieve_all_files<C: Connection<Backend = Sqlite>>(
    connection: &C,
) -> Result<Vec<models::File>> {
    use crate::database::inner::schema::files::dsl::*;
    let matches = files.load::<models::File>(connection)?;
    Ok(matches)
}

pub fn get_latest_files<C: Connection<Backend = Sqlite>>(
    connection: &C,
    count: i64,
) -> Result<Vec<models::File>> {
    use crate::database::inner::schema::files::dsl::*;

    let matches = files
        .order_by(added.desc())
        .limit(count)
        .load::<models::File>(connection)?;

    Ok(matches)
}

pub fn file_set_valid<C: Connection<Backend = Sqlite>>(
    connection: &C,
    file_id: i32,
    is_valid: bool,
) -> Result<usize> {
    use crate::database::inner::schema::files::dsl::*;

    debug!("Setting file ID {} to valid = {}", file_id, is_valid);

    Ok(diesel::update(files.filter(id.eq(file_id)))
        .set(valid.eq(is_valid))
        .execute(connection)?)
}

pub fn retrieve_object<C: Connection<Backend = Sqlite>>(
    connection: &C,
    object_address: Address,
) -> Result<Vec<Entry>> {
    use crate::database::inner::schema::data::dsl::*;

    let matches = data
        .filter(entity.eq(object_address.encode()?))
        .or_filter(value.eq(EntryValue::Address(object_address).to_string()?))
        .load::<models::Entry>(connection)?;
    let entries = matches
        .iter()
        .map(Entry::try_from)
        .filter_map(Result::ok)
        .collect();

    Ok(entries)
}

pub fn bulk_retrieve_objects<C: Connection<Backend = Sqlite>>(
    connection: &C,
    object_addresses: Vec<Address>,
) -> Result<Vec<Entry>> {
    use crate::database::inner::schema::data::dsl::*;

    let matches = data
        .filter(
            entity.eq_any(
                object_addresses
                    .iter()
                    .filter_map(|addr| addr.encode().ok()),
            ),
        )
        // .or_filter(value.eq(EntryValue::Address(object_address).to_str()?))
        .load::<models::Entry>(connection)?;
    let entries = matches
        .iter()
        .map(Entry::try_from)
        .filter_map(Result::ok)
        .collect();

    Ok(entries)
}

pub fn remove_object<C: Connection<Backend = Sqlite>>(
    connection: &C,
    object_address: Address,
) -> Result<usize> {
    use crate::database::inner::schema::data::dsl::*;

    debug!("Deleting {}!", object_address);

    let matches = data
        .filter(identity.eq(object_address.encode()?))
        .or_filter(entity.eq(object_address.encode()?))
        .or_filter(value.eq(EntryValue::Address(object_address).to_string()?));

    Ok(diesel::delete(matches).execute(connection)?)
}

pub fn query<C: Connection<Backend = Sqlite>>(connection: &C, query: Query) -> Result<Vec<Entry>> {
    use crate::database::inner::schema::data::dsl::*;

    trace!("Querying: {:?}", query);

    let db_query = data.filter(query.to_sqlite_predicates()?);

    trace!("DB query: {}", debug_query(&db_query));

    let matches = db_query.load::<models::Entry>(connection)?;

    let entries = matches
        .iter()
        .map(Entry::try_from)
        .filter_map(Result::ok)
        .collect();

    Ok(entries)
}

pub fn insert_entry<C: Connection<Backend = Sqlite>>(
    connection: &C,
    entry: Entry,
) -> Result<Address> {
    debug!("Inserting: {}", entry);

    let insert_entry = models::Entry::try_from(&entry)?;

    let entry = Entry::try_from(&insert_entry)?;

    let result = diesel::insert_into(data::table)
        .values(insert_entry)
        .execute(connection);

    if let Some(error) = result.err() {
        match error {
            Error::DatabaseError(DatabaseErrorKind::UniqueViolation, _) => {}
            _ => return Err(anyhow!(error)),
        }
    }

    Ok(Address::Hash(entry.hash()?))
}

#[derive(Debug)]
pub struct ConnectionOptions {
    pub enable_foreign_keys: bool,
    pub busy_timeout: Option<Duration>,
}

impl ConnectionOptions {
    pub fn apply(&self, conn: &SqliteConnection) -> QueryResult<()> {
        if self.enable_foreign_keys {
            conn.execute("PRAGMA foreign_keys = ON;")?;
        }
        if let Some(duration) = self.busy_timeout {
            conn.execute(&format!("PRAGMA busy_timeout = {};", duration.as_millis()))?;
        }
        Ok(())
    }
}

impl diesel::r2d2::CustomizeConnection<SqliteConnection, diesel::r2d2::Error>
    for ConnectionOptions
{
    fn on_acquire(&self, conn: &mut SqliteConnection) -> Result<(), diesel::r2d2::Error> {
        self.apply(conn).map_err(diesel::r2d2::Error::QueryError)
    }
}

pub type DbPool = r2d2::Pool<ConnectionManager<SqliteConnection>>;

pub struct OpenResult {
    pub pool: DbPool,
    pub new: bool,
}

pub const DATABASE_FILENAME: &str = "upend.sqlite3";

pub fn open_upend<P: AsRef<Path>>(
    dirpath: P,
    db_path: Option<PathBuf>,
    reinitialize: bool,
) -> Result<OpenResult> {
    embed_migrations!("./migrations/upend/");

    let database_path = db_path.unwrap_or_else(|| dirpath.as_ref().join(DATABASE_FILENAME));

    if reinitialize {
        let _ = fs::remove_file(&database_path);
    }
    let new = !database_path.exists();

    let manager = ConnectionManager::<SqliteConnection>::new(database_path.to_str().unwrap());
    let pool = r2d2::Pool::builder()
        .connection_customizer(Box::new(ConnectionOptions {
            enable_foreign_keys: true,
            busy_timeout: Some(Duration::from_secs(30)),
        }))
        .build(manager)?;

    trace!("Pool created, running migrations...");

    embedded_migrations::run_with_output(
        &pool.get()?,
        &mut LoggerSink {
            ..Default::default()
        },
    )?;

    trace!("Initializing types...");

    initialize_types(&pool)?;

    Ok(OpenResult { pool, new })
}

fn initialize_types(pool: &DbPool) -> Result<()> {
    insert_entry(&pool.get()?, Entry::try_from(&*TYPE_INVARIANT)?)?;
    upend_insert_addr!(&pool.get()?, TYPE_ADDR, IS_OF_TYPE_ATTR, TYPE_ADDR);
    upend_insert_val!(&pool.get()?, TYPE_ADDR, TYPE_ID_ATTR, TYPE_IS_ATTR);
    Ok(())
}