package dbml

import (
	"strings"
	"testing"

	"git.warky.dev/wdevs/relspecgo/pkg/models"
	"git.warky.dev/wdevs/relspecgo/pkg/readers"
)

func parse(t *testing.T, strict bool, src string) (*models.Database, error) {
	t.Helper()
	r := NewReader(&readers.ReaderOptions{StrictDirectives: strict})
	return r.parseDBML(src)
}

func firstTable(t *testing.T, db *models.Database) *models.Table {
	t.Helper()
	if len(db.Schemas) == 0 || len(db.Schemas[0].Tables) == 0 {
		t.Fatal("no table parsed")
	}
	return db.Schemas[0].Tables[0]
}

func TestDirectives_AttachAtEachLocation(t *testing.T) {
	src := `@postgres: search_path myapp

Table myapp.events {
  id bigint [pk]
  created_at timestamp [not null]
  @postgres(id): identity always
  @postgres: partition by RANGE (created_at)

  indexes {
    (created_at) [name: 'idx_events_created']
    @postgres: with (fillfactor=90)
  }
}
`
	db, err := parse(t, false, src)
	if err != nil {
		t.Fatalf("parse: %v", err)
	}

	if !models.HasDirective(db.Metadata, "postgres", "search_path") {
		t.Errorf("database-level directive missing: %+v", db.Metadata)
	}

	tbl := firstTable(t, db)
	if !models.HasDirective(tbl.Metadata, "postgres", "partition") {
		t.Errorf("table-level directive missing: %+v", tbl.Metadata)
	}

	col := tbl.Columns["id"]
	if col == nil || !models.HasDirective(col.Metadata, "postgres", "identity") {
		t.Errorf("column-level directive missing")
	}
	// Verbatim args preserved.
	if d := models.DirectivesForNamespace(col.Metadata, "postgres"); len(d) != 1 || d[0].Args != "identity always" {
		t.Errorf("column directive args = %+v", d)
	}

	var idx *models.Index
	for _, i := range tbl.Indexes {
		idx = i
	}
	if idx == nil || !models.HasDirective(idx.Metadata, "postgres", "with") {
		t.Errorf("index-level directive missing: %+v", idx)
	}
}

func TestDirectives_RepeatablePreservedAndOrdered(t *testing.T) {
	src := `Table s.t {
  id int [pk]
  @postgres: with (fillfactor=90)
  @postgres: with (autovacuum_enabled=off)
}
`
	db, err := parse(t, false, src)
	if err != nil {
		t.Fatalf("parse: %v", err)
	}
	tbl := firstTable(t, db)
	got := models.DirectivesForNamespace(tbl.Metadata, "postgres")
	if len(got) != 2 {
		t.Fatalf("got %d directives, want 2", len(got))
	}
	if got[0].Args != "with (fillfactor=90)" || got[1].Args != "with (autovacuum_enabled=off)" {
		t.Errorf("repeatable directives out of order: %+v", got)
	}
}

func TestDirectives_SingletonDuplicateErrors(t *testing.T) {
	src := `Table s.t {
  id int [pk]
  @postgres: partition by RANGE (a)
  @postgres: partition by LIST (b)
}
`
	_, err := parse(t, false, src)
	if err == nil || !strings.Contains(err.Error(), "duplicate") {
		t.Fatalf("want duplicate error, got %v", err)
	}
	if !strings.Contains(err.Error(), "line 4") {
		t.Errorf("error not line-numbered: %v", err)
	}
}

func TestDirectives_MalformedErrors(t *testing.T) {
	cases := map[string]string{
		"no colon":       "@postgres partition by x",
		"empty args":     "@postgres:",
		"bad namespace":  "@Postgres: partition by x",
		"numeric prefix": "@1x: foo",
	}
	for name, line := range cases {
		t.Run(name, func(t *testing.T) {
			src := "Table s.t {\n  id int [pk]\n  " + line + "\n}\n"
			_, err := parse(t, false, src)
			if err == nil {
				t.Fatalf("want error for %q", line)
			}
			if !strings.Contains(err.Error(), "line 3") {
				t.Errorf("error not line-numbered: %v", err)
			}
		})
	}
}

func TestDirectives_UnknownPreservedNonStrict(t *testing.T) {
	src := `Table s.t {
  id int [pk]
  @postgres: frobnicate all the things
  @clickhouse: engine MergeTree
}
`
	db, err := parse(t, false, src)
	if err != nil {
		t.Fatalf("parse: %v", err)
	}
	tbl := firstTable(t, db)
	if !models.HasDirective(tbl.Metadata, "postgres", "frobnicate") {
		t.Error("unknown postgres key not preserved")
	}
	if !models.HasDirective(tbl.Metadata, "clickhouse", "engine") {
		t.Error("unknown namespace not preserved")
	}
}

func TestDirectives_StrictErrors(t *testing.T) {
	src := `Table s.t {
  id int [pk]
  @postgres: frobnicate x
}
`
	_, err := parse(t, true, src)
	if err == nil || !strings.Contains(err.Error(), "strict mode") {
		t.Fatalf("want strict-mode error, got %v", err)
	}
}

func TestDirectives_UnknownColumnTargetErrors(t *testing.T) {
	src := `Table s.t {
  id int [pk]
  @postgres(missing): identity always
}
`
	_, err := parse(t, false, src)
	if err == nil || !strings.Contains(err.Error(), "not found") {
		t.Fatalf("want unknown-column error, got %v", err)
	}
}

func TestDirectives_WrongLocationErrors(t *testing.T) {
	// partition is table-only.
	src := "@postgres: partition by RANGE (x)\n\nTable s.t {\n  id int [pk]\n}\n"
	_, err := parse(t, false, src)
	if err == nil || !strings.Contains(err.Error(), "not valid at database level") {
		t.Fatalf("want location error, got %v", err)
	}
}