using Npgsql;

using NpgsqlRest;

using NpgsqlRestClient;

namespace NpgsqlRestTests;

[Collection("TestFixture")]

public class WatchDbFingerprintTests

{

[Fact]

public void Fingerprint_TracksDiscoveryResult_Exactly()

{

using var conn = Database.CreateConnection();

conn.Open();

void Exec(string sql)

{

using var c = conn.CreateCommand();

c.CommandText = sql;

c.ExecuteNonQuery();

}

// The fingerprint is the routine discovery query itself, hashed server-side — so it tracks the

// discovered endpoints by definition, with the source's configured filters applied.

var source = new RoutineSource(nameSimilarTo: "watch\\_fp\\_%");

string Fp() => WatchDbPoller.GetFingerprint(conn, source)!;

Exec("drop function if exists watch_fp_test_fn(int)");

Exec("drop table if exists watch_fp_typed cascade");

var fp0 = Fp();

fp0.Should().NotBeNullOrEmpty();

// create function → changes

Exec("create function watch_fp_test_fn(a int) returns int language sql as 'select a'");

var fp1 = Fp();

fp1.Should().NotBe(fp0, "creating a function must change the fingerprint");

// replace body → changes (the result includes pg_get_functiondef)

Exec("create or replace function watch_fp_test_fn(a int) returns int language sql as 'select a + 1'");

var fp2 = Fp();

fp2.Should().NotBe(fp1, "replacing a function body must change the fingerprint");

// comment = annotations → changes

Exec("comment on function watch_fp_test_fn(int) is 'HTTP GET'");

var fp3 = Fp();

fp3.Should().NotBe(fp2, "COMMENT ON a function (annotations) must change the fingerprint");

// temp table → must NOT change

Exec("create temp table watch_fp_tmp(id int)");

var fp4 = Fp();

fp4.Should().Be(fp3, "temp objects must not look like a database change");

// a table NOT used by any discovered routine → must NOT change (precision: the discovery

// result doesn't mention it, so the hash cannot move)

Exec("drop table if exists watch_fp_unrelated");

Exec("create table watch_fp_unrelated(id int)");

var fp5 = Fp();

fp5.Should().Be(fp4, "an unrelated table is not part of the discovery result");

Exec("drop table watch_fp_unrelated");

// a table USED as a return type → its shape is part of the result: altering it changes the endpoint

Exec("create table watch_fp_typed(id int)");

Exec("create function watch_fp_typed_fn() returns setof watch_fp_typed language sql as 'select * from watch_fp_typed'");

var fp6 = Fp();

fp6.Should().NotBe(fp5, "a new routine (returning a table type) must change the fingerprint");

Exec("alter table watch_fp_typed add column name text");

var fp7 = Fp();

fp7.Should().NotBe(fp6, "adding a column to a table used as a return type reshapes the endpoint");

// cleanup; drops → change

Exec("drop function watch_fp_typed_fn()");

Exec("drop table watch_fp_typed");

Exec("drop function watch_fp_test_fn(int)");

var fp8 = Fp();

fp8.Should().NotBe(fp7, "dropping functions must change the fingerprint");

}

}