Cleanup parser statements, add delete and insert statement, add TASKS.md for tracking tasks

sql/parseCreateStatement.go

@@ -0,0 +1,219 @@
+package sql
+
+import (
+	"fmt"
+	"slices"
+)
+
+func (p *Parser) parseCreateTable() (*CreateTableStatement, error) {
+	if !p.expectNext(TABLE) {
+		return nil, p.unexpectedToken()
+	}
+
+	tok, ok := p.expectOne(QUOTE, SINGLE_QUOTE, BACKQUOTE, IDENT, IF)
+	if !ok {
+		return nil, p.unexpectedToken(IDENT, IF)
+	}
+
+	switch tok {
+	case IF:
+		if !p.expectSequence(NOT, EXISTS) {
+			return nil, p.unexpectedToken()
+		}
+		p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+		fallthrough
+	case QUOTE, SINGLE_QUOTE, BACKQUOTE:
+		if !p.expectNext(IDENT) {
+			return nil, p.unexpectedToken()
+		}
+	}
+	_, _, lit := p.rescan()
+
+	stmt := CreateTableStatement{
+		TableName: lit,
+		Columns:   make([]Column, 0),
+	}
+
+	p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+	if !p.expectNext(LPAREN) {
+		return nil, p.unexpectedToken(LPAREN)
+	}
+
+	for {
+		p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+		_, tok, _ := p.scan()
+
+		switch tok {
+		case RPAREN:
+			if !p.expectNext(SEMI) {
+				return nil, p.unexpectedToken(SEMI)
+			}
+			return &stmt, nil
+
+		case IDENT:
+			column, err := p.parseColumn()
+			if err != nil {
+				return nil, err
+			}
+			stmt.Columns = append(stmt.Columns, column)
+
+		// TODO: HANDLE AND SAVE CONSTRAINTS
+		case CONSTRAINT:
+			p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+			if !p.expectNext(IDENT) {
+				return nil, p.unexpectedToken()
+			}
+			// _, _, constraintName := p.rescan()
+			p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+
+		case FOREIGN:
+			if !p.expectSequence(KEY, LPAREN) {
+				return nil, p.unexpectedToken()
+			}
+
+			p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+
+			if !p.expectNext(IDENT) {
+				return nil, p.unexpectedToken()
+			}
+			_, _, columnName := p.rescan()
+
+			p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+
+			if !p.expectSequence(RPAREN, REFERENCES) {
+				return nil, p.unexpectedToken()
+			}
+
+			ref, err := p.references()
+			if err != nil {
+				return nil, err
+			}
+
+			column := slices.IndexFunc(stmt.Columns, func(c Column) bool {
+				return c.Name == columnName
+			})
+
+			stmt.Columns[column].Extra = append(stmt.Columns[column].Extra, ref)
+
+		case PRIMARY:
+			if !p.expectSequence(KEY, LPAREN) {
+				return nil, p.unexpectedToken()
+			}
+			p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+
+			if !p.expectNext(IDENT) {
+				return nil, p.unexpectedToken()
+			}
+
+			primaryKeyNames := make([]string, 0)
+			_, _, columnName := p.rescan()
+			primaryKeyNames = append(primaryKeyNames, columnName)
+			p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+
+			for {
+				tok, ok := p.expectOne(RPAREN, COMMA)
+				if !ok {
+					return nil, p.unexpectedToken()
+				}
+				if tok == RPAREN {
+					break
+				}
+
+				p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+				if !p.expectNext(IDENT) {
+					return nil, p.unexpectedToken()
+				}
+
+				_, _, columnName := p.rescan()
+
+				p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+				primaryKeyNames = append(primaryKeyNames, columnName)
+			}
+
+			for _, pkName := range primaryKeyNames {
+				column := slices.IndexFunc(stmt.Columns, func(c Column) bool {
+					return c.Name == pkName
+				})
+				stmt.Columns[column].Extra = append(stmt.Columns[column].Extra, "PRIMARY_KEY")
+			}
+
+		case COMMA:
+			continue
+
+		default:
+			return nil, p.unexpectedToken(IDENT, RPAREN, FOREIGN, COMMA)
+		}
+	}
+}
+
+func (p *Parser) parseColumn() (Column, error) {
+	_, _, lit := p.rescan()
+	column := Column{Name: lit, Extra: make([]string, 0)}
+	p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+
+	if _, ok := p.expectOne(TEXT, INTEGER, REAL, BLOB, NUMERIC); !ok {
+		return Column{}, p.unexpectedToken(TEXT, INTEGER, REAL, BLOB, NUMERIC)
+	}
+	_, _, column.Type = p.rescan()
+
+	for {
+		_, tok, lit := p.scan()
+		switch tok {
+		case COMMA:
+			return column, nil
+		case RPAREN:
+			p.unscan()
+			return column, nil
+
+		case PRIMARY:
+			fallthrough
+		case NOT:
+			if _, ok := p.expectOne(NULL, KEY); !ok {
+				return Column{}, p.unexpectedToken(NULL, KEY)
+			}
+			_, _, rlit := p.rescan()
+			column.Extra = append(column.Extra, fmt.Sprintf("%v_%v", lit, rlit))
+
+		case REFERENCES:
+			ref, err := p.references()
+			if err != nil {
+				return Column{}, err
+			}
+			column.Extra = append(column.Extra, ref)
+
+		case AUTOINCREMENT:
+			column.Extra = append(column.Extra, "AUTOINCREMENT")
+
+		default:
+			return Column{}, p.unexpectedToken(COMMA, RPAREN, PRIMARY, NOT, REFERENCES)
+		}
+	}
+}
+
+func (p *Parser) references() (string, error) {
+	p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+	if !p.expectNext(IDENT) {
+		return "", p.unexpectedToken(IDENT)
+	}
+	_, _, referenceTableName := p.rescan()
+	p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+
+	if !p.expectNext(LPAREN) {
+		return "", p.unexpectedToken()
+	}
+
+	p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+
+	if !p.expectNext(IDENT) {
+		return "", p.unexpectedToken()
+	}
+	_, _, referenceColumnName := p.rescan()
+
+	p.consumeIfOne(QUOTE, SINGLE_QUOTE, BACKQUOTE)
+
+	if !p.expectNext(RPAREN) {
+		return "", p.unexpectedToken(RPAREN)
+	}
+
+	return fmt.Sprintf("ref %v.%v", referenceTableName, referenceColumnName), nil
+}