1 files changed, 160 insertions, 0 deletions
diff --git a/src/db/cards.rs b/src/db/cards.rs
new file mode 100644
index 0000000..6d3e28d
--- /dev/null
+++ b/src/db/cards.rs
@@ -0,0 +1,160 @@
+use anyhow::Result;
+use rusqlite::{params, Connection};
+
+use crate::model::DbEntry;
+use crate::util::time;
+use crate::{
+    model::{Card, Question},
+    space_repetition,
+    util::serialization,
+};
+
+pub fn all(conn: &Connection) -> Result<Vec<DbEntry>> {
+    let mut stmt = conn.prepare("SELECT question, responses, deleted FROM cards")?;
+
+    let res: Result<Vec<DbEntry>, rusqlite::Error> = stmt
+        .query_map([], |row| {
+            let responses: String = row.get(1)?;
+            Ok(DbEntry {
+                question: row.get(0)?,
+                responses: serialization::line_to_words(&responses),
+                deleted: row.get(2)?,
+            })
+        })?
+        .collect();
+
+    Ok(res?)
+}
+
+pub fn insert(conn: &mut Connection, questions: &Vec<Question>) -> Result<()> {
+    let now = time::seconds_since_unix_epoch()?;
+    let state = serde_json::to_string(&space_repetition::init())?;
+
+    let tx = conn.transaction()?;
+    for Question {
+        question,
+        responses,
+    } in questions
+    {
+        let responses = serialization::words_to_line(responses);
+        tx.execute(
+            "
+            INSERT INTO cards (question, responses, state, created, ready)
+            VALUES (?, ?, ?, ?, ?)
+            ",
+            params![question, responses, state, now, now],
+        )?;
+    }
+    tx.commit()?;
+    Ok(())
+}
+
+pub fn delete(conn: &mut Connection, questions: &Vec<Question>) -> Result<()> {
+    let now = time::seconds_since_unix_epoch()?;
+
+    let tx = conn.transaction()?;
+    for Question {
+        question,
+        responses,
+    } in questions
+    {
+        let responses = serialization::words_to_line(responses);
+        tx.execute(
+            "UPDATE cards SET deleted = ? WHERE question = ? AND responses = ?",
+            params![now, question, responses],
+        )?;
+    }
+    tx.commit()?;
+    Ok(())
+}
+
+pub fn undelete(conn: &mut Connection, questions: &Vec<Question>) -> Result<()> {
+    let tx = conn.transaction()?;
+    for Question {
+        question,
+        responses,
+    } in questions
+    {
+        let responses = serialization::words_to_line(responses);
+        tx.execute(
+            "UPDATE cards SET deleted = NULL WHERE question = ? AND responses = ?",
+            params![question, responses],
+        )?;
+    }
+    tx.commit()?;
+    Ok(())
+}
+
+pub fn pick_random_ready(conn: &Connection) -> Option<Card> {
+    let now = time::seconds_since_unix_epoch().ok()?;
+
+    let mut stmt = conn
+        .prepare(
+            "
+        SELECT question, responses, state, ready
+        FROM cards
+        WHERE deleted IS NULL AND ready <= ?
+        ORDER BY RANDOM()
+        LIMIT 1
+        ",
+        )
+        .ok()?;
+
+    let mut rows = stmt.query([now]).ok()?;
+    let row = rows.next().ok()??;
+    let state_str: String = row.get(2).ok()?;
+    let responses_str: String = row.get(1).ok()?;
+
+    Some(Card {
+        question: row.get(0).ok()?,
+        responses: serialization::line_to_words(&responses_str),
+        state: serde_json::from_str(&state_str).ok()?,
+        ready: row.get(3).ok()?,
+    })
+}
+
+pub fn next_ready(conn: &Connection) -> Option<u64> {
+    let mut stmt = conn
+        .prepare(
+            "
+        SELECT ready
+        FROM cards
+        WHERE deleted IS NULL
+        ORDER BY ready
+        LIMIT 1
+    ",
+        )
+        .ok()?;
+
+    let mut rows = stmt.query([]).ok()?;
+    let row = rows.next().ok()??;
+    row.get(0).ok()?
+}
+
+pub fn count_available(conn: &Connection) -> Option<i32> {
+    let now = time::seconds_since_unix_epoch().ok()?;
+    let mut stmt = conn
+        .prepare("SELECT COUNT(*) FROM cards WHERE ready <= ? AND deleted IS NULL")
+        .ok()?;
+
+    let mut rows = stmt.query([now]).ok()?;
+    let row = rows.next().ok()??;
+    row.get(0).ok()?
+}
+
+pub fn update(conn: &Connection, question: &str, state: &space_repetition::State) -> Result<()> {
+    let now = time::seconds_since_unix_epoch()?;
+    let ready = now + state.get_interval_seconds();
+    let state_str = serde_json::to_string(state)?;
+
+    conn.execute(
+        "
+        UPDATE cards
+        SET state = ?, updated = ?, ready = ?
+        WHERE question = ?
+        ",
+        params![state_str, now, ready, question],
+    )?;
+
+    Ok(())
+}