/**
 * Database Import — intermediate model
 *
 * These types are the contract between the introspection layer (which reads a
 * live Postgres database) and the conversion layer (which turns that into a
 * `.apsorc`). Keeping the introspector behind the `Introspector` interface lets
 * the conversion logic and the command be unit-tested with a fake source,
 * without a real database connection.
 */
/** ON DELETE referential action of a foreign key. */
export type OnDeleteAction = "CASCADE" | "RESTRICT" | "SET NULL" | "NO ACTION" | "SET DEFAULT";
/** A single introspected column. */
export interface IntrospectedColumn {
    name: string;
    /** pg_catalog udt_name, e.g. "int4", "varchar", "_text", "timestamptz". */
    udtName: string;
    /** information_schema.data_type, used to detect "USER-DEFINED" (enum) and "ARRAY". */
    dataType: string;
    nullable: boolean;
    /** Raw default expression, e.g. "nextval('...')", "now()", "'active'::text". */
    default: string | null;
    charMaxLength: number | null;
    numericPrecision: number | null;
    numericScale: number | null;
    ordinal: number;
    /** True when the column's type is a user-defined enum. */
    isEnum: boolean;
    /** Links to IntrospectedEnum.name when isEnum is true. */
    enumTypeName?: string;
}
/** A foreign key constraint (may be composite). */
export interface IntrospectedFk {
    /** Local column(s) participating in the FK. */
    columns: string[];
    referencedTable: string;
    referencedColumns: string[];
    onDelete: OnDeleteAction;
}
/** A unique constraint (may be composite). */
export interface IntrospectedUnique {
    name: string;
    columns: string[];
}
/** A secondary index (may be composite). */
export interface IntrospectedIndex {
    name: string;
    columns: string[];
    unique: boolean;
}
/** A user-defined enum type and its labels (in sort order). */
export interface IntrospectedEnum {
    name: string;
    labels: string[];
}
/** A single introspected base table. */
export interface IntrospectedTable {
    name: string;
    columns: IntrospectedColumn[];
    /** Ordered primary-key column names ([] if the table has no primary key). */
    primaryKey: string[];
    foreignKeys: IntrospectedFk[];
    uniqueConstraints: IntrospectedUnique[];
    indexes: IntrospectedIndex[];
}
/** The full result of introspecting one Postgres schema. */
export interface IntrospectedSchema {
    schema: string;
    tables: IntrospectedTable[];
    enums: IntrospectedEnum[];
    /** Objects intentionally not imported, surfaced in the summary report. */
    skipped: {
        views: string[];
        systemSchemas: string[];
    };
}
/**
 * The boundary the command depends on. The real implementation
 * (PgIntrospector) connects to Postgres; tests provide a fake.
 */
export interface Introspector {
    introspect(schema: string): Promise<IntrospectedSchema>;
}
/**
 * Everything the import couldn't represent losslessly, plus counts, used to
 * print a summary the user can review before/after writing the `.apsorc`.
 */
export interface ImportReport {
    tablesImported: string[];
    relationships: number;
    viewsSkipped: string[];
    systemSchemasSkipped: string[];
    warnings: {
        /** "table.column" whose Postgres array type was reduced to text. */
        arraysLossy: string[];
        /** Tables with composite primary keys (emitted as primary:true fields). */
        compositePks: string[];
        /** Tables with composite foreign keys (kept as scalar columns, no relationship). */
        compositeFks: string[];
        /** Tables whose single PK is not named "id" (emitted as a primary:true field). */
        nonStandardPks: string[];
        /** Tables with no primary key at all. */
        noPrimaryKey: string[];
        /** Columns whose type was unknown and defaulted to text. */
        typesDefaulted: Array<{
            column: string;
            udt: string;
        }>;
        /** FK columns whose name could not be round-tripped to a relationship name. */
        fkColumnNameUnmapped: string[];
        /** "table.column" defaults that were dropped (unsupported expressions). */
        defaultsDropped: string[];
        /** Tables that look like pure join tables (candidates for manual ManyToMany). */
        joinTablesDetected: string[];
    };
}