Initial commit

1 files changed, 152 insertions, 0 deletions

diff --git a/qlite/src/database.vala b/qlite/src/database.vala
new file mode 100644
index 00000000..285e10a8
--- /dev/null
+++ b/qlite/src/database.vala
@@ -0,0 +1,152 @@
+using Sqlite;
+
+namespace Qlite {
+
+public errordomain DatabaseError {
+    ILLEGAL_QUERY,
+    NOT_SUPPORTED,
+    OPEN_ERROR,
+    PREPARE_ERROR,
+    EXEC_ERROR,
+    NON_UNIQUE,
+    ILLEGAL_REFERENCE,
+    NOT_INITIALIZED
+}
+
+public class Database {
+    private string file_name;
+    private Sqlite.Database db;
+    private long expected_version;
+    private Table[] tables;
+
+    private Column<string> meta_name = new Column.Text("name") { primary_key = true };
+    private Column<long> meta_int_val = new Column.Long("int_val");
+    private Column<string> meta_text_val = new Column.Text("text_val");
+    private Table meta_table;
+
+    public bool debug = false;
+
+    public Database(string file_name, long expected_version) {
+        this.file_name = file_name;
+        this.expected_version = expected_version;
+        meta_table = new Table(this, "_meta");
+        meta_table.init({meta_name, meta_int_val, meta_text_val});
+    }
+
+    public void init(Table[] tables) throws DatabaseError {
+        print(@"Intializing database at $file_name\n");
+        Sqlite.config(Config.SERIALIZED);
+        int ec = Sqlite.Database.open_v2(file_name, out db, OPEN_READWRITE | OPEN_CREATE | 0x00010000);
+        if (ec != Sqlite.OK) {
+            throw new DatabaseError.OPEN_ERROR(@"SQLite error: $(db.errcode()) - $(db.errmsg())");
+        }
+        this.tables = tables;
+        start_migration();
+    }
+
+    public void ensure_init() throws DatabaseError {
+        if (tables == null) throw new DatabaseError.NOT_INITIALIZED(@"Database $file_name was not initialized, call init()");
+    }
+
+    private void start_migration() throws DatabaseError {
+        meta_table.create_table_at_version(expected_version);
+        long old_version = 0;
+        try {
+            Row? row = meta_table.row_with(meta_name, "version");
+            old_version = row == null ? -1 : (long) row[meta_int_val];
+        } catch (DatabaseError e) {
+            old_version = -1;
+        }
+        foreach (Table t in tables) {
+            t.create_table_at_version(old_version);
+        }
+        if (expected_version != old_version) {
+            foreach (Table t in tables) {
+                t.add_columns_for_version(old_version, expected_version);
+            }
+            migrate(old_version);
+            foreach (Table t in tables) {
+                t.delete_columns_for_version(old_version, expected_version);
+            }
+            if (old_version == -1) {
+                meta_table.insert().value(meta_name, "version").value(meta_int_val, expected_version).perform();
+            } else {
+                meta_table.update().with(meta_name, "=", "version").set(meta_int_val, expected_version).perform();
+            }
+        }
+    }
+
+    internal int errcode() {
+        return db.errcode();
+    }
+
+    internal string errmsg() {
+        return db.errmsg();
+    }
+
+    internal int64 last_insert_rowid() {
+        return db.last_insert_rowid();
+    }
+
+    // To be implemented by actual implementation if required
+    // new table columns are added, outdated columns are still present and will be removed afterwards
+    public virtual void migrate(long old_version) throws DatabaseError {
+    }
+
+    public QueryBuilder select(Column[]? columns = null) throws DatabaseError {
+        ensure_init();
+        return new QueryBuilder(this).select(columns);
+    }
+
+    public InsertBuilder insert() throws DatabaseError {
+        ensure_init();
+        return new InsertBuilder(this);
+    }
+
+    public UpdateBuilder update(Table table) throws DatabaseError {
+        ensure_init();
+        return new UpdateBuilder(this, table);
+    }
+
+    public UpdateBuilder update_named(string table) throws DatabaseError {
+        ensure_init();
+        return new UpdateBuilder.for_name(this, table);
+    }
+
+    public DeleteBuilder delete() throws DatabaseError {
+        ensure_init();
+        return new DeleteBuilder(this);
+    }
+
+    public Row.RowIterator query_sql(string sql, string[]? args = null) throws DatabaseError {
+        ensure_init();
+        return new Row.RowIterator(this, sql, args);
+    }
+
+    public Statement prepare(string sql) throws DatabaseError {
+        ensure_init();
+        if (debug) print(@"prepare: $sql\n");
+        Sqlite.Statement statement;
+        if (db.prepare_v2(sql, sql.length, out statement) != OK) {
+            throw new DatabaseError.PREPARE_ERROR(@"SQLite error: $(db.errcode()) - $(db.errmsg())");
+        }
+        return statement;
+    }
+
+    public void exec(string sql) throws DatabaseError {
+        ensure_init();
+        if (db.exec(sql) != OK) {
+            throw new DatabaseError.EXEC_ERROR(@"SQLite error: $(db.errcode()) - $(db.errmsg())");
+        }
+    }
+
+    public bool is_known_column(string table, string field) throws DatabaseError {
+        ensure_init();
+        foreach (Table t in tables) {
+            if (t.is_known_column(field)) return true;
+        }
+        return false;
+    }
+}
+
+}
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