feat: ✨ Added Sqlite reader

pkg/readers/sqlite/queries.go

@@ -0,0 +1,306 @@
+package sqlite
+
+import (
+	"fmt"
+	"strings"
+
+	"git.warky.dev/wdevs/relspecgo/pkg/models"
+)
+
+// queryTables retrieves all tables from the SQLite database
+func (r *Reader) queryTables() ([]*models.Table, error) {
+	query := `
+		SELECT name
+		FROM sqlite_master
+		WHERE type = 'table'
+		  AND name NOT LIKE 'sqlite_%'
+		ORDER BY name
+	`
+
+	rows, err := r.db.QueryContext(r.ctx, query)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	tables := make([]*models.Table, 0)
+	for rows.Next() {
+		var tableName string
+
+		if err := rows.Scan(&tableName); err != nil {
+			return nil, err
+		}
+
+		table := models.InitTable(tableName, "main")
+		tables = append(tables, table)
+	}
+
+	return tables, rows.Err()
+}
+
+// queryViews retrieves all views from the SQLite database
+func (r *Reader) queryViews() ([]*models.View, error) {
+	query := `
+		SELECT name, sql
+		FROM sqlite_master
+		WHERE type = 'view'
+		ORDER BY name
+	`
+
+	rows, err := r.db.QueryContext(r.ctx, query)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	views := make([]*models.View, 0)
+	for rows.Next() {
+		var viewName string
+		var sql *string
+
+		if err := rows.Scan(&viewName, &sql); err != nil {
+			return nil, err
+		}
+
+		view := models.InitView(viewName, "main")
+		if sql != nil {
+			view.Definition = *sql
+		}
+
+		views = append(views, view)
+	}
+
+	return views, rows.Err()
+}
+
+// queryColumns retrieves all columns for a given table or view
+func (r *Reader) queryColumns(tableName string) (map[string]*models.Column, error) {
+	query := fmt.Sprintf("PRAGMA table_info(%s)", tableName)
+
+	rows, err := r.db.QueryContext(r.ctx, query)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	columns := make(map[string]*models.Column)
+
+	for rows.Next() {
+		var cid int
+		var name, dataType string
+		var notNull, pk int
+		var defaultValue *string
+
+		if err := rows.Scan(&cid, &name, &dataType, &notNull, &defaultValue, &pk); err != nil {
+			return nil, err
+		}
+
+		column := models.InitColumn(name, tableName, "main")
+		column.Type = r.mapDataType(strings.ToUpper(dataType))
+		column.NotNull = (notNull == 1)
+		column.IsPrimaryKey = (pk > 0)
+		column.Sequence = uint(cid + 1)
+
+		if defaultValue != nil {
+			column.Default = *defaultValue
+		}
+
+		// Check for autoincrement (SQLite uses INTEGER PRIMARY KEY AUTOINCREMENT)
+		if pk > 0 && strings.ToUpper(dataType) == "INTEGER" {
+			column.AutoIncrement = r.isAutoIncrement(tableName, name)
+		}
+
+		columns[name] = column
+	}
+
+	return columns, rows.Err()
+}
+
+// isAutoIncrement checks if a column is autoincrement
+func (r *Reader) isAutoIncrement(tableName, columnName string) bool {
+	// Check sqlite_sequence table or parse CREATE TABLE statement
+	query := `
+		SELECT sql
+		FROM sqlite_master
+		WHERE type = 'table' AND name = ?
+	`
+
+	var sql string
+	err := r.db.QueryRowContext(r.ctx, query, tableName).Scan(&sql)
+	if err != nil {
+		return false
+	}
+
+	// Check if the SQL contains AUTOINCREMENT for this column
+	return strings.Contains(strings.ToUpper(sql), strings.ToUpper(columnName)+" INTEGER PRIMARY KEY AUTOINCREMENT") ||
+		strings.Contains(strings.ToUpper(sql), strings.ToUpper(columnName)+" INTEGER AUTOINCREMENT")
+}
+
+// queryPrimaryKey retrieves the primary key constraint for a table
+func (r *Reader) queryPrimaryKey(tableName string) (*models.Constraint, error) {
+	query := fmt.Sprintf("PRAGMA table_info(%s)", tableName)
+
+	rows, err := r.db.QueryContext(r.ctx, query)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var pkColumns []string
+
+	for rows.Next() {
+		var cid int
+		var name, dataType string
+		var notNull, pk int
+		var defaultValue *string
+
+		if err := rows.Scan(&cid, &name, &dataType, &notNull, &defaultValue, &pk); err != nil {
+			return nil, err
+		}
+
+		if pk > 0 {
+			pkColumns = append(pkColumns, name)
+		}
+	}
+
+	if len(pkColumns) == 0 {
+		return nil, nil
+	}
+
+	// Create primary key constraint
+	constraintName := fmt.Sprintf("%s_pkey", tableName)
+	constraint := models.InitConstraint(constraintName, models.PrimaryKeyConstraint)
+	constraint.Schema = "main"
+	constraint.Table = tableName
+	constraint.Columns = pkColumns
+
+	return constraint, rows.Err()
+}
+
+// queryForeignKeys retrieves all foreign key constraints for a table
+func (r *Reader) queryForeignKeys(tableName string) ([]*models.Constraint, error) {
+	query := fmt.Sprintf("PRAGMA foreign_key_list(%s)", tableName)
+
+	rows, err := r.db.QueryContext(r.ctx, query)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	// Group foreign keys by id (since composite FKs have multiple rows)
+	fkMap := make(map[int]*models.Constraint)
+
+	for rows.Next() {
+		var id, seq int
+		var referencedTable, fromColumn, toColumn string
+		var onUpdate, onDelete, match string
+
+		if err := rows.Scan(&id, &seq, &referencedTable, &fromColumn, &toColumn, &onUpdate, &onDelete, &match); err != nil {
+			return nil, err
+		}
+
+		if _, exists := fkMap[id]; !exists {
+			constraintName := fmt.Sprintf("%s_%s_fkey", tableName, referencedTable)
+			if id > 0 {
+				constraintName = fmt.Sprintf("%s_%s_fkey_%d", tableName, referencedTable, id)
+			}
+
+			constraint := models.InitConstraint(constraintName, models.ForeignKeyConstraint)
+			constraint.Schema = "main"
+			constraint.Table = tableName
+			constraint.ReferencedSchema = "main"
+			constraint.ReferencedTable = referencedTable
+			constraint.OnUpdate = onUpdate
+			constraint.OnDelete = onDelete
+			constraint.Columns = []string{}
+			constraint.ReferencedColumns = []string{}
+
+			fkMap[id] = constraint
+		}
+
+		// Add column to the constraint
+		fkMap[id].Columns = append(fkMap[id].Columns, fromColumn)
+		fkMap[id].ReferencedColumns = append(fkMap[id].ReferencedColumns, toColumn)
+	}
+
+	// Convert map to slice
+	foreignKeys := make([]*models.Constraint, 0, len(fkMap))
+	for _, fk := range fkMap {
+		foreignKeys = append(foreignKeys, fk)
+	}
+
+	return foreignKeys, rows.Err()
+}
+
+// queryIndexes retrieves all indexes for a table
+func (r *Reader) queryIndexes(tableName string) ([]*models.Index, error) {
+	query := fmt.Sprintf("PRAGMA index_list(%s)", tableName)
+
+	rows, err := r.db.QueryContext(r.ctx, query)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	indexes := make([]*models.Index, 0)
+
+	for rows.Next() {
+		var seq int
+		var name string
+		var unique int
+		var origin string
+		var partial int
+
+		if err := rows.Scan(&seq, &name, &unique, &origin, &partial); err != nil {
+			return nil, err
+		}
+
+		// Skip auto-generated indexes (origin = 'pk' for primary keys, etc.)
+		// origin: c = CREATE INDEX, u = UNIQUE constraint, pk = PRIMARY KEY
+		if origin == "pk" || origin == "u" {
+			continue
+		}
+
+		index := models.InitIndex(name, tableName, "main")
+		index.Unique = (unique == 1)
+
+		// Get index columns
+		columns, err := r.queryIndexColumns(name)
+		if err != nil {
+			return nil, err
+		}
+		index.Columns = columns
+
+		indexes = append(indexes, index)
+	}
+
+	return indexes, rows.Err()
+}
+
+// queryIndexColumns retrieves the columns for a specific index
+func (r *Reader) queryIndexColumns(indexName string) ([]string, error) {
+	query := fmt.Sprintf("PRAGMA index_info(%s)", indexName)
+
+	rows, err := r.db.QueryContext(r.ctx, query)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	columns := make([]string, 0)
+
+	for rows.Next() {
+		var seqno, cid int
+		var name *string
+
+		if err := rows.Scan(&seqno, &cid, &name); err != nil {
+			return nil, err
+		}
+
+		if name != nil {
+			columns = append(columns, *name)
+		}
+	}
+
+	return columns, rows.Err()
+}