qlite: add basic (outer) join functionality

4 files changed, 118 insertions, 55 deletions

diff --git a/qlite/src/column.vala b/qlite/src/column.vala
index 9c201885..daa6a59f 100644
--- a/qlite/src/column.vala
+++ b/qlite/src/column.vala
@@ -3,6 +3,8 @@ using Sqlite;
 namespace Qlite {
 
 public abstract class Column<T> {
+    public const string DEFALT_TABLE_NAME = "";
+
     public string name { get; private set; }
     public string? default { get; set; }
     public int sqlite_type { get; private set; }
@@ -12,16 +14,21 @@ public abstract class Column<T> {
     public virtual bool not_null { get; set; }
     public long min_version { get; set; default = -1; }
     public long max_version { get; set; default = long.MAX; }
+    internal Table table { get; set; }
 
-    public abstract T get(Row row);
+    public abstract T get(Row row, string? table_name = DEFALT_TABLE_NAME);
 
-    public virtual bool is_null(Row row) {
+    public virtual bool is_null(Row row, string? table_name = DEFALT_TABLE_NAME) {
         return false;
     }
 
     internal abstract void bind(Statement stmt, int index, T value);
 
     public string to_string() {
+        return table == null ? name : (table.name + "." + name);
+    }
+
+    public string to_column_definition() {
         string res = name;
         switch (sqlite_type) {
             case INTEGER:
@@ -58,12 +65,12 @@ public abstract class Column<T> {
             base(name, INTEGER);
         }
 
-        public override int get(Row row) {
-            return (int) row.get_integer(name);
+        public override int get(Row row, string? table_name = DEFALT_TABLE_NAME) {
+            return (int) row.get_integer(name, table_name == DEFALT_TABLE_NAME ? table.name : table_name);
         }
 
-        public override bool is_null(Row row) {
-            return !row.has_integer(name);
+        public override bool is_null(Row row, string? table_name = DEFALT_TABLE_NAME) {
+            return !row.has_integer(name, table_name == DEFALT_TABLE_NAME ? table.name : table_name);
         }
 
         internal override void bind(Statement stmt, int index, int value) {
@@ -76,12 +83,12 @@ public abstract class Column<T> {
             base(name, INTEGER);
         }
 
-        public override long get(Row row) {
-            return (long) row.get_integer(name);
+        public override long get(Row row, string? table_name = DEFALT_TABLE_NAME) {
+            return (long) row.get_integer(name, table_name == DEFALT_TABLE_NAME ? table.name : table_name);
         }
 
-        public override bool is_null(Row row) {
-            return !row.has_integer(name);
+        public override bool is_null(Row row, string? table_name = DEFALT_TABLE_NAME) {
+            return !row.has_integer(name, table_name == DEFALT_TABLE_NAME ? table.name : table_name);
         }
 
         internal override void bind(Statement stmt, int index, long value) {
@@ -94,12 +101,12 @@ public abstract class Column<T> {
             base(name, FLOAT);
         }
 
-        public override double get(Row row) {
-            return row.get_real(name);
+        public override double get(Row row, string? table_name = DEFALT_TABLE_NAME) {
+            return row.get_real(name, table_name == DEFALT_TABLE_NAME ? table.name : table_name);
         }
 
-        public override bool is_null(Row row) {
-            return !row.has_real(name);
+        public override bool is_null(Row row, string? table_name = DEFALT_TABLE_NAME) {
+            return !row.has_real(name, table_name == DEFALT_TABLE_NAME ? table.name : table_name);
         }
 
         internal override void bind(Statement stmt, int index, double value) {
@@ -112,12 +119,12 @@ public abstract class Column<T> {
             base(name, TEXT);
         }
 
-        public override string? get(Row row) {
-            return row.get_text(name);
+        public override string? get(Row row, string? table_name = DEFALT_TABLE_NAME) {
+            return row.get_text(name, table_name == DEFALT_TABLE_NAME ? table.name : table_name);
         }
 
-        public override bool is_null(Row row) {
-            return get(row) == null;
+        public override bool is_null(Row row, string? table_name = DEFALT_TABLE_NAME) {
+            return get(row, table_name == DEFALT_TABLE_NAME ? table.name : table_name) == null;
         }
 
         internal override void bind(Statement stmt, int index, string? value) {
@@ -136,11 +143,11 @@ public abstract class Column<T> {
 
         public override bool not_null { get { return true; } set {} }
 
-        public override string get(Row row) {
-            return (!)row.get_text(name);
+        public override string get(Row row, string? table_name = DEFALT_TABLE_NAME) {
+            return (!)row.get_text(name, table_name == DEFALT_TABLE_NAME ? table.name : table_name);
         }
 
-        public override bool is_null(Row row) {
+        public override bool is_null(Row row, string? table_name = DEFALT_TABLE_NAME) {
             return false;
         }
 
@@ -154,8 +161,8 @@ public abstract class Column<T> {
             base(name, TEXT);
         }
 
-        public override bool get(Row row) {
-            return row.get_text(name) == "1";
+        public override bool get(Row row, string? table_name = DEFALT_TABLE_NAME) {
+            return row.get_text(name, table_name == DEFALT_TABLE_NAME ? table.name : table_name) == "1";
         }
 
         internal override void bind(Statement stmt, int index, bool value) {
@@ -168,8 +175,8 @@ public abstract class Column<T> {
             base(name, INTEGER);
         }
 
-        public override bool get(Row row) {
-            return row.get_integer(name) == 1;
+        public override bool get(Row row, string? table_name = DEFALT_TABLE_NAME) {
+            return row.get_integer(name, table_name == DEFALT_TABLE_NAME ? table.name : table_name) == 1;
         }
 
         internal override void bind(Statement stmt, int index, bool value) {
diff --git a/qlite/src/query_builder.vala b/qlite/src/query_builder.vala
index 9ca5bf25..d1254b53 100644
--- a/qlite/src/query_builder.vala
+++ b/qlite/src/query_builder.vala
@@ -33,12 +33,12 @@ public class QueryBuilder : StatementBuilder {
 
     public QueryBuilder select(Column[] columns = {}) {
         this.columns = columns;
-        if (columns.length == 0) {
+        if (columns.length != 0) {
             for (int i = 0; i < columns.length; i++) {
                 if (column_selector == "*") {
-                    column_selector = columns[0].name;
+                    column_selector = columns[i].to_string();
                 } else {
-                    column_selector += ", " + columns[i].name;
+                    column_selector += ", " + columns[i].to_string();
                 }
             }
         } else {
@@ -65,14 +65,33 @@ public class QueryBuilder : StatementBuilder {
         return this;
     }
 
-    public QueryBuilder join(string table, string on) {
-        joins += @"JOIN $table ON $on";
+    public QueryBuilder outer_join_with<T>(Table table, Column<T> lhs, Column<T> rhs, string? as = null) {
+        return outer_join_on(table, @"$lhs = $rhs", as);
+    }
+
+    public QueryBuilder outer_join_on(Table table, string on, string? as = null) {
+        if (as == null) as = table.name;
+        joins += @" LEFT OUTER JOIN $(table.name) AS $as ON $on";
+        return this;
+    }
+
+    public QueryBuilder join_with<T>(Table table, Column<T> lhs, Column<T> rhs, string? as = null) {
+        return join_on(table, @"$lhs = $rhs", as);
+    }
+
+    public QueryBuilder join_on(Table table, string on, string? as = null) {
+        if (as == null) as = table.name;
+        joins += @" JOIN $(table.name) AS $as ON $on";
+        return this;
+    }
+
+    internal QueryBuilder join_name(string table_name, string on) {
+        joins += @" JOIN $table_name ON $on";
         return this;
     }
 
     public QueryBuilder where(string selection, string[] selection_args = {}) {
-        if (this.selection != "1") error("selection was already done, but where() was called.");
-        this.selection = selection;
+        this.selection = @"($(this.selection)) AND ($selection)";
         foreach (string arg in selection_args) {
             this.selection_args += new StatementBuilder.StringField(arg);
         }
@@ -82,17 +101,17 @@ public class QueryBuilder : StatementBuilder {
     public QueryBuilder with<T>(Column<T> column, string comp, T value) {
         if ((column.unique || column.primary_key) && comp == "=") single_result = true;
         selection_args += new Field<T>(column, value);
-        selection = @"($selection) AND $table_name.$(column.name) $comp ?";
+        selection = @"($selection) AND $column $comp ?";
         return this;
     }
 
     public QueryBuilder with_null<T>(Column<T> column) {
-        selection = @"($selection) AND $table_name.$(column.name) ISNULL";
+        selection = @"($selection) AND $column ISNULL";
         return this;
     }
 
     public QueryBuilder without_null<T>(Column<T> column) {
-        selection = @"($selection) AND $table_name.$(column.name) NOT NULL";
+        selection = @"($selection) AND $column NOT NULL";
         return this;
     }
 
@@ -155,13 +174,13 @@ public class QueryBuilder : StatementBuilder {
     }
 
     class OrderingTerm {
-        Column column;
+        Column? column;
         string column_name;
         string dir;
 
         public OrderingTerm(Column column, string dir) {
             this.column = column;
-            this.column_name = column.name;
+            this.column_name = column.to_string();
             this.dir = dir;
         }
 
@@ -190,7 +209,7 @@ public class MatchQueryBuilder : QueryBuilder {
         base(db);
         if (table.fts_columns == null) error("MATCH query on non FTS table");
         from(table);
-        join(@"_fts_$table_name", @"_fts_$table_name.docid = $table_name.rowid");
+        join_name(@"_fts_$table_name", @"_fts_$table_name.docid = $table_name.rowid");
     }
 
     public MatchQueryBuilder match(Column<string> column, string match) {
diff --git a/qlite/src/row.vala b/qlite/src/row.vala
index be459719..d3807f41 100644
--- a/qlite/src/row.vala
+++ b/qlite/src/row.vala
@@ -10,15 +10,21 @@ public class Row {
 
     internal Row(Statement stmt) {
         for (int i = 0; i < stmt.column_count(); i++) {
+            string column_name;
+            if (stmt.column_origin_name(i) != null) {
+                column_name = @"$(stmt.column_table_name(i)).$(stmt.column_origin_name(i))";
+            } else {
+                column_name = stmt.column_name(i);
+            }
             switch(stmt.column_type(i)) {
                 case TEXT:
-                    text_map[stmt.column_name(i)] = stmt.column_text(i);
+                    text_map[column_name] = stmt.column_text(i);
                     break;
                 case INTEGER:
-                    int_map[stmt.column_name(i)] = (long) stmt.column_int64(i);
+                    int_map[column_name] = (long) stmt.column_int64(i);
                     break;
                 case FLOAT:
-                    real_map[stmt.column_name(i)] = stmt.column_double(i);
+                    real_map[column_name] = stmt.column_double(i);
                     break;
             }
         }
@@ -28,27 +34,54 @@ public class Row {
         return field[this];
     }
 
-    public string? get_text(string field) {
-        if (text_map.has_key(field)) {
-            return text_map[field];
+    private string field_name(string field, string? table) {
+        if (table != null) {
+            return @"$table.$field";
+        } else {
+            return field;
+        }
+    }
+
+    public string? get_text(string field, string? table = null) {
+        if (text_map.has_key(field_name(field, table))) {
+            return text_map[field_name(field, table)];
         }
         return null;
     }
 
-    public long get_integer(string field) {
-        return int_map[field];
+    public long get_integer(string field, string? table = null) {
+        return int_map[field_name(field, table)];
+    }
+
+    public bool has_integer(string field, string? table = null) {
+        return int_map.has_key(field_name(field, table));
     }
 
-    public bool has_integer(string field) {
-        return int_map.has_key(field);
+    public double get_real(string field, string? table = null, double def = 0) {
+        return real_map[field_name(field, table)] ?? def;
     }
 
-    public double get_real(string field, double def = 0) {
-        return real_map[field] ?? def;
+    public bool has_real(string field, string? table = null) {
+        return real_map.has_key(field_name(field, table)) && real_map[field_name(field, table)] != null;
     }
 
-    public bool has_real(string field) {
-        return real_map.has_key(field) && real_map[field] != null;
+    public string to_string() {
+        string ret = "{";
+
+        foreach (string key in text_map.keys) {
+            if (ret.length > 1) ret += ", ";
+            ret = @"$ret$key: \"$(text_map[key])\"";
+        }
+        foreach (string key in int_map.keys) {
+            if (ret.length > 1) ret += ", ";
+            ret = @"$ret$key: $(int_map[key])";
+        }
+        foreach (string key in real_map.keys) {
+            if (ret.length > 1) ret += ", ";
+            ret = @"$ret$key: $(real_map[key])";
+        }
+
+        return ret + "}";
     }
 }
 
diff --git a/qlite/src/table.vala b/qlite/src/table.vala
index 8725c4c9..607a396c 100644
--- a/qlite/src/table.vala
+++ b/qlite/src/table.vala
@@ -19,6 +19,10 @@ public class Table {
     public void init(Column[] columns, string constraints = "") {
         this.columns = columns;
         this.constraints = constraints;
+
+        foreach(Column c in columns) {
+            c.table = this;
+        }
     }
 
     public void fts(Column[] columns) {
@@ -28,7 +32,7 @@ public class Table {
         string cnames = "";
         string cnews = "";
         foreach (Column c in columns) {
-            cs += @", $c";
+            cs += @", $(c.to_column_definition())";
             cnames += @", $(c.name)";
             cnews += @", new.$(c.name)";
         }
@@ -140,7 +144,7 @@ public class Table {
         for (int i = 0; i < columns.length; i++) {
             Column c = columns[i];
             if (c.min_version <= version && c.max_version >= version) {
-                sql += @"$(i > 0 ? "," : "") $c";
+                sql += @"$(i > 0 ? "," : "") $(c.to_column_definition())";
             }
         }
         sql += @"$constraints)";
@@ -163,7 +167,7 @@ public class Table {
         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");
+                    db.exec(@"ALTER TABLE $name ADD COLUMN $(c.to_column_definition())");
                 } catch (Error e) {
                     error("Qlite Error: Add columns for version");
                 }