schema

type Action string

type Column struct {
	Name       string
	DBType     string // Raw DB type string (e.g., "uuid", "text", "integer")
	IsNullable bool
	HasDefault bool
	DefaultVal string // Raw default expression as string
	IsArray    bool
	ArrayDims  int // Number of array dimensions (1 for int[], 2 for int[][], etc.)

	// IsAutoIncrement is true for SERIAL/BIGSERIAL or GENERATED ALWAYS AS IDENTITY.
	IsAutoIncrement bool

	// EnumName is set when the column type is a user-defined enum.
	EnumName string
}

type Enum struct {
	Schema string
	Name   string
	Values []string
}

type ForeignKey struct {
	Name       string   // Constraint name
	Columns    []string // Local column names
	RefTable   string   // Referenced table name
	RefSchema  string   // Referenced table schema
	RefColumns []string // Referenced column names
	OnDelete   Action
	OnUpdate   Action
}

type Index struct {
	Name    string
	Columns []string
	Unique  bool
}

type Parser interface {
	// ParseFile parses a single SQL file and returns the schema objects found.
	ParseFile(path string) (*Schema, error)

	// ParseDir parses all SQL files in a directory and merges them into one Schema.
	ParseDir(dir string) (*Schema, error)

	// ParseString parses SQL from a string.
	ParseString(sql string) (*Schema, error)
}

type PolymorphicDef struct {
	Table      string            // Table with type+id columns
	TypeColumn string            // Column holding type discriminator
	IDColumn   string            // Column holding FK value
	Targets    map[string]string // TypeValue -> target table name
}

type PrimaryKey struct {
	Name    string   // Constraint name (may be empty)
	Columns []string // Column names in PK order
}

type RelationType int

type Relationship struct {
	Type RelationType

	// Local side
	Table   string   // Table this relationship is defined on
	Columns []string // Local columns involved

	// Foreign side
	ForeignTable   string   // The other table
	ForeignColumns []string // Columns on the other table

	// For many-to-many: the join table details
	JoinTable          string
	JoinLocalColumns   []string // Join table columns pointing to local table
	JoinForeignColumns []string // Join table columns pointing to foreign table

	// ForeignKey is the FK that produced this relationship.
	ForeignKey *ForeignKey

	// For polymorphic relationships
	TypeColumn string // Column that holds the type discriminator (e.g., "commentable_type")
	IDColumn   string // Column that holds the FK value (e.g., "commentable_id")
	TypeValue  string // Value of the type column for this specific relationship (e.g., "User")
}

type Schema struct {
	// Name is the schema name (e.g., "public" for Postgres default).
	Name string

	Tables []*Table
	Enums  []*Enum
	Views  []*View
}

type Table struct {
	Schema      string // Schema name (e.g., "public")
	Name        string // Table name as it appears in the DB
	Columns     []*Column
	PrimaryKey  *PrimaryKey
	ForeignKeys []*ForeignKey
	Indexes     []*Index
	Unique      []*UniqueConstraint

	// Relationships are inferred from foreign keys after parsing.
	Relationships []*Relationship
}

type UniqueConstraint struct {
	Name    string
	Columns []string
}

type View struct {
	Schema         string
	Name           string
	Columns        []*Column
	IsMaterialized bool
	// Query is the raw SQL of the view definition, if available.
	Query string
}