1 files changed, 97 insertions, 0 deletions
diff --git a/src/database/friends.rs b/src/database/friends.rs
new file mode 100644
index 0000000..0b78488
--- /dev/null
+++ b/src/database/friends.rs
@@ -0,0 +1,97 @@
+use tracing::instrument;
+
+use crate::{
+    database::{self, users::user_from_row},
+    types::user::{User, FOLLOWED, FOLLOWING, NO_RELATION},
+};
+
+pub fn init() -> Result<(), rusqlite::Error> {
+    let sql = "
+        CREATE TABLE IF NOT EXISTS friends (
+            follower_id     INTEGER NOT NULL,
+            followee_id     INTEGER NOT NULL,
+            FOREIGN KEY(follower_id) REFERENCES users(user_id),
+            FOREIGN KEY(followee_id) REFERENCES users(user_id),
+            PRIMARY KEY (follower_id, followee_id)
+        );
+    ";
+    let conn = database::connect()?;
+    conn.execute(sql, ())?;
+    Ok(())
+}
+
+#[instrument()]
+pub fn get_friend_status(user_id_1: u64, user_id_2: u64) -> Result<u8, rusqlite::Error> {
+    tracing::trace!("Retrieving friend status");
+    let conn = database::connect()?;
+    let mut stmt = conn.prepare("SELECT * FROM friends WHERE (follower_id = ? AND followee_id = ?) OR (follower_id = ? AND followee_id = ?);")?;
+    let mut status = NO_RELATION;
+    let rows: Vec<u64> = stmt
+        .query_map([user_id_1, user_id_2, user_id_2, user_id_1], |row| {
+            let id: u64 = row.get(0)?;
+            Ok(id)
+        })?
+        .into_iter()
+        .flatten()
+        .collect();
+
+    for follower in rows {
+        if follower == user_id_1 {
+            status |= FOLLOWING;
+        }
+
+        if follower == user_id_2 {
+            status |= FOLLOWED;
+        }
+    }
+
+    Ok(status)
+}
+
+#[instrument()]
+pub fn get_friends(user_id: u64) -> Result<Vec<User>, rusqlite::Error> {
+    tracing::trace!("Retrieving friends");
+    let conn = database::connect()?;
+    let mut stmt = conn.prepare(
+        "
+        SELECT * 
+        FROM users u 
+        WHERE EXISTS (
+            SELECT NULL 
+            FROM friends f 
+            WHERE u.user_id = f.follower_id
+            AND f.followee_id = ?
+        )
+        AND EXISTS (
+            SELECT NULL
+            FROM friends f
+            WHERE u.user_id = f.followee_id
+            AND f.follower_id = ?
+        )
+    ",
+    )?;
+    let row = stmt.query_map([user_id, user_id], |row| {
+        let row = user_from_row(row, true)?;
+        Ok(row)
+    })?;
+    Ok(row.into_iter().flatten().collect())
+}
+
+#[instrument()]
+pub fn set_following(user_id_1: u64, user_id_2: u64) -> Result<bool, rusqlite::Error> {
+    tracing::trace!("Setting following");
+    let conn = database::connect()?;
+    let mut stmt =
+        conn.prepare("INSERT OR REPLACE INTO friends (follower_id, followee_id) VALUES (?,?)")?;
+    let changes = stmt.execute([user_id_1, user_id_2])?;
+    Ok(changes == 1)
+}
+
+#[instrument()]
+pub fn remove_following(user_id_1: u64, user_id_2: u64) -> Result<bool, rusqlite::Error> {
+    tracing::trace!("Removing following");
+    let conn = database::connect()?;
+    let mut stmt = conn.prepare("DELETE FROM friends WHERE follower_id = ? AND followee_id = ?")?;
+    let changes = stmt.execute([user_id_1, user_id_2])?;
+    Ok(changes == 1)
+}