// Copyright (c) 2022 Teddy Wing
//
// This file is part of Yaqlite.
//
// Yaqlite is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Yaqlite is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Yaqlite. If not, see .
use rusqlite;
use yaml_rust::yaml;
use std::collections::HashSet;
mod sql;
mod write;
pub(crate) use sql::*;
pub use write::*;
/// Insert a YAML document into the given table in the database.
pub fn db_insert(
doc: &mut yaml::Yaml,
tx: &rusqlite::Transaction,
table_name: &str,
table_columns: &HashSet,
) -> Result<(), crate::Error> {
with_hash(
doc,
&mut |hash| {
use std::borrow::Cow;
hash_filter_table_columns(hash, &table_columns);
let mut stmt = tx.prepare(
&format!(
r#"
INSERT INTO "{}"
({})
VALUES
({});
"#,
table_name,
// Wrap column names in quotes.
hash.keys()
.map(|k| k.as_str())
.filter(|k| k.is_some())
// Always `Some`.
.map(|k| format!(r#""{}""#, k.unwrap()))
.collect::>()
.join(", "),
format!("{}?", "?, ".repeat(hash.len() - 1)),
)
)?;
let values = hash.values().map(|v| Yaml(Cow::Borrowed(v)));
stmt.insert(rusqlite::params_from_iter(values))?;
Ok(())
}
)
}
/// TODO
pub fn db_update(
doc: &mut yaml::Yaml,
tx: &rusqlite::Transaction,
table_name: &str,
table_columns: &HashSet,
primary_key_column: &str,
record_id: &str,
) -> Result<(), crate::Error> {
with_hash(
doc,
&mut |hash| {
use std::borrow::Cow;
hash_filter_table_columns(hash, &table_columns);
let mut stmt = tx.prepare(
&format!(
r#"
UPDATE "{}"
SET
{}
WHERE {} = ?;
"#,
table_name,
// List of:
// "column_name" = ?,
// "column_name" = ?
hash.keys()
.map(|k| k.as_str())
.filter(|k| k.is_some())
// Always `Some`.
.map(|k| format!(r#""{}" = ?"#, k.unwrap()))
.collect::>()
.join(", "),
primary_key_column,
),
)?;
// TODO: convert to &[&dyn ToSql] ?
// let values = hash.values().map(|v| Yaml(Cow::Borrowed(v)));
// values.push(primary_key);
// stmt.execute(rusqlite::params_from_iter(values))?;
// let values: Vec<&dyn rusqlite::ToSql>;
//
// for v in hash.values() {
// values.push(&Yaml(Cow::Borrowed(v)));
// }
//
// stmt.execute(values)?;
// let values: dyn Iterator- = hash.values();
// values = values.map(|v| Yaml(Cow::Borrowed(v)));
// values.chain(&[&primary_key]);
// stmt.execute(rusqlite::params_from_iter(values))?;
let mut values: Vec<_> = hash.values()
.map(|v| Yaml(Cow::Borrowed(v)))
.map(|v| Box::new(v) as Box)
.collect();
values.push(Box::new(record_id));
stmt.execute(rusqlite::params_from_iter(values))?;
Ok(())
}
)
}
/// Parse a YAML document and run a function for all hashes in the document.
fn with_hash(
doc: &mut yaml::Yaml,
run: &mut F,
) -> Result<(), crate::Error>
where F: FnMut(&mut yaml::Hash) -> Result<(), crate::Error>
{
match doc {
yaml::Yaml::Array(ref mut array) => {
for yaml_value in array {
with_hash(yaml_value, run)?;
}
}
yaml::Yaml::Hash(ref mut hash) => {
run(hash)?;
}
_ => {}
}
Ok(())
}
/// Remove keys in `table_columns` from `hash`.
fn hash_filter_table_columns(
hash: &mut yaml::Hash,
table_columns: &HashSet,
) {
let keys: Vec = hash.keys().map(|k| k.clone()).collect();
let columns_as_yaml: Vec = table_columns.iter()
.map(|c| yaml::Yaml::from_str(c))
.collect();
for key in keys.iter() {
if !columns_as_yaml.contains(key) {
hash.remove(key);
}
}
}