using Sqlite; namespace Qlite { public class Table { protected Database db; public string name { get; private set; } protected Column[]? columns; private string constraints = ""; private string[] post_statements = {}; public Table(Database db, string name) { this.db = db; this.name = name; } public void init(Column[] columns, string constraints = "") { this.columns = columns; this.constraints = constraints; } public void unique(Column[] columns, string? on_conflict = null) { constraints += ", UNIQUE ("; bool first = true; foreach (Column c in columns) { if (!first) constraints += ", "; constraints += c.name; first = false; } constraints += ")"; if (on_conflict != null) { constraints += " ON CONFLICT " + (!)on_conflict; } } public void add_post_statement(string stmt) { post_statements += stmt; } public void index(string index_name, Column[] columns, bool unique = false) { string stmt = @"CREATE $(unique ? "UNIQUE" : "") INDEX IF NOT EXISTS $index_name ON $name ("; bool first = true; foreach (Column c in columns) { if (!first) stmt += ", "; stmt += c.name; first = false; } stmt += ")"; add_post_statement(stmt); } private void ensure_init() { if (columns == null) error("Table %s was not initialized, call init()", name); } public QueryBuilder select(Column[]? columns = null) { ensure_init(); return db.select(columns).from(this); } public InsertBuilder insert() { ensure_init(); return db.insert().into(this); } public UpdateBuilder update() { ensure_init(); return db.update(this); } public UpsertBuilder upsert() { ensure_init(); return db.upsert(this); } public DeleteBuilder delete() { ensure_init(); return db.delete().from(this); } public RowOption row_with(Column column, T value) { ensure_init(); if (!column.unique && !column.primary_key) error("%s is not suited to identify a row, but used with row_with()", column.name); return select().with(column, "=", value).row(); } public bool is_known_column(string column) { ensure_init(); foreach (Column c in columns) { if (c.name == column) return true; } return false; } public void create_table_at_version(long version) { ensure_init(); string sql = @"CREATE TABLE IF NOT EXISTS $name ("; bool first = true; for (int i = 0; i < columns.length; i++) { Column c = columns[i]; if (c.min_version <= version && c.max_version >= version) { sql += @"$(!first ? "," : "") $c"; first = false; } } sql += @"$constraints)"; try { db.exec(sql); } catch (Error e) { error("Qlite Error: Create table at version"); } } public void add_columns_for_version(long old_version, long new_version) { ensure_init(); foreach (Column c in columns) { if (c.min_version <= new_version && c.max_version >= new_version && c.min_version > old_version) { try { db.exec(@"ALTER TABLE $name ADD COLUMN $c"); } catch (Error e) { error("Qlite Error: Add columns for version"); } } } } public void delete_columns_for_version(long old_version, long new_version) { bool column_deletion_required = false; string column_list = ""; foreach (Column c in columns) { if (c.min_version <= new_version && c.max_version >= new_version) { if (column_list == "") { column_list = c.name; } else { column_list += ", " + c.name; } } if (!(c.min_version <= new_version && c.max_version >= new_version) && c.min_version <= old_version && c.max_version >= old_version) { column_deletion_required = true; } } if (column_deletion_required) { try { db.exec(@"ALTER TABLE $name RENAME TO _$(name)_$old_version"); create_table_at_version(new_version); db.exec(@"INSERT INTO $name ($column_list) SELECT $column_list FROM _$(name)_$old_version"); db.exec(@"DROP TABLE _$(name)_$old_version"); } catch (Error e) { error("Qlite Error: Delete volumns for version change"); } } } internal void post() { foreach (string stmt in post_statements) { try { db.exec(stmt); } catch (Error e) { error("Qlite Error: Post"); } } } } }