package storage

import (
	"path/filepath"
	"testing"

	"github.com/sandrodach/mindsift/internal/collab"
	"github.com/sandrodach/mindsift/internal/domain"
)

func newSyncTestStore(t *testing.T) (*Store, *domain.User) {
	t.Helper()
	store, err := NewStore(filepath.Join(t.TempDir(), "sync.db"))
	if err != nil {
		t.Fatalf("store: %v", err)
	}
	t.Cleanup(func() { _ = store.Close() })
	u, err := store.CreateUser("owner@example.com", "hash", "Owner", "member")
	if err != nil {
		t.Fatalf("user: %v", err)
	}
	return store, u
}

func flatBlocks(spec ...[3]interface{}) []domain.DocumentBlock { // {id, level, content}
	out := make([]domain.DocumentBlock, len(spec))
	for i, s := range spec {
		out[i] = domain.DocumentBlock{ID: s[0].(string), Level: s[1].(int), Content: s[2].(string), Type: "bullet"}
	}
	return out
}

func outline(blocks []domain.DocumentBlock) [][2]interface{} {
	out := make([][2]interface{}, len(blocks))
	for i, b := range blocks {
		out[i] = [2]interface{}{b.ID, b.Level}
	}
	return out
}

func sameOutline(t *testing.T, got []domain.DocumentBlock, want []domain.DocumentBlock) {
	t.Helper()
	if len(got) != len(want) {
		t.Fatalf("got %v, want %v", outline(got), outline(want))
	}
	for i := range got {
		if got[i].ID != want[i].ID || got[i].Level != want[i].Level || got[i].Content != want[i].Content {
			t.Fatalf("block %d: got %v, want %v", i, outline(got), outline(want))
		}
	}
}

func headSeq(t *testing.T, s *Store, docID string) int64 {
	t.Helper()
	_, head, err := s.GetDocOpsSince(docID, 0, 1)
	if err != nil {
		t.Fatal(err)
	}
	return head
}

func TestLegacySaveRoundTripsThroughTheLog(t *testing.T) {
	s, u := newSyncTestStore(t)
	initial := flatBlocks(
		[3]interface{}{"a", 0, "Projekt"},
		[3]interface{}{"b", 1, "Aufgabe 1"},
		[3]interface{}{"c", 2, "Detail"},
		[3]interface{}{"d", 1, "Aufgabe 2"},
		[3]interface{}{"e", 0, "Anderes"},
	)
	doc, err := s.CreateDocument(u.ID, "", "Notiz", "📄", "", initial, nil, false)
	if err != nil {
		t.Fatal(err)
	}
	got, _ := s.GetDocumentByID(u.ID, doc.ID)
	sameOutline(t, got.Blocks, initial)

	// Saving the same content again must not produce any log entries
	head := headSeq(t, s, doc.ID)
	if _, err := s.UpdateDocument(u.ID, doc.ID, nil, nil, nil, &initial, nil, nil); err != nil {
		t.Fatal(err)
	}
	if h := headSeq(t, s, doc.ID); h != head {
		t.Fatalf("unchanged save wrote %d log entries", h-head)
	}

	// Reorder, outdent, edit and delete in one save
	changed := flatBlocks(
		[3]interface{}{"e", 0, "Anderes"},
		[3]interface{}{"a", 0, "Projekt (neu)"},
		[3]interface{}{"d", 1, "Aufgabe 2"},
		[3]interface{}{"c", 1, "Detail"},
		[3]interface{}{"n", 2, "Neu"},
	)
	if _, err := s.UpdateDocument(u.ID, doc.ID, nil, nil, nil, &changed, nil, nil); err != nil {
		t.Fatal(err)
	}
	got, _ = s.GetDocumentByID(u.ID, doc.ID)
	sameOutline(t, got.Blocks, changed)

	// The log alone must rebuild exactly this state
	entries, _, err := s.GetDocOpsSince(doc.ID, 0, 10_000)
	if err != nil {
		t.Fatal(err)
	}
	replay := collab.NewDoc()
	for _, e := range entries {
		replay.ApplyEffect(e.Effect)
	}
	sameOutline(t, flatDocumentBlocks(doc.ID, replay), changed)
}

func TestApplyDocOpsIsIdempotent(t *testing.T) {
	s, u := newSyncTestStore(t)
	doc, _ := s.CreateDocument(u.ID, "", "Notiz", "📄", "", flatBlocks([3]interface{}{"a", 0, "Start"}), nil, false)
	a := collab.Actor{UserID: u.ID, ClientID: "tab1", Name: "Owner"}
	text := "Geändert"
	op := collab.Op{OpID: "op-1", Kind: collab.OpSetContent, BlockID: "a", BaseVersion: 1, Content: &text}

	first, head1, err := s.ApplyDocOps(doc.ID, a, []collab.Op{op}, nil)
	if err != nil || first[0].Status != collab.StatusApplied {
		t.Fatalf("first: %+v %v", first, err)
	}
	// Resend after a lost response: same result, nothing applied twice
	again, head2, err := s.ApplyDocOps(doc.ID, a, []collab.Op{op}, nil)
	if err != nil || again[0] != first[0] || head2 != head1 {
		t.Fatalf("retry changed something: %+v head %d -> %d", again, head1, head2)
	}
}

func TestInsertCannotReuseBlockIDOfAnotherNote(t *testing.T) {
	s, u := newSyncTestStore(t)
	other, _ := s.CreateDocument(u.ID, "", "Andere", "📄", "", flatBlocks([3]interface{}{"shared_id", 0, "Fremd"}), nil, false)
	doc, _ := s.CreateDocument(u.ID, "", "Notiz", "📄", "", nil, nil, false)
	a := collab.Actor{UserID: u.ID, ClientID: "tab1"}
	content, root := "Übernahme", ""
	res, _, err := s.ApplyDocOps(doc.ID, a, []collab.Op{{OpID: "x", Kind: collab.OpInsert, BlockID: "shared_id", ParentID: &root, OrderKey: "a0", Content: &content}}, nil)
	if err != nil || res[0].Reason != "exists" {
		t.Fatalf("got %+v %v", res, err)
	}
	got, _ := s.GetDocumentByID(u.ID, other.ID)
	if got.Blocks[0].Content != "Fremd" {
		t.Fatal("block of another note was modified")
	}
}

func TestDocRole(t *testing.T) {
	s, owner := newSyncTestStore(t)
	reader, _ := s.CreateUser("reader@example.com", "hash", "Reader", "member")
	writer, _ := s.CreateUser("writer@example.com", "hash", "Writer", "member")
	stranger, _ := s.CreateUser("stranger@example.com", "hash", "Stranger", "member")
	doc, _ := s.CreateDocument(owner.ID, "", "Notiz", "📄", "", nil, nil, false)

	now := domain.NowISO()
	if _, err := s.db.Exec(`INSERT INTO doc_shares (id, doc_id, user_id, permission, created_at, created_by) VALUES ('s1', ?, ?, 'read', ?, ?), ('s2', ?, ?, 'write', ?, ?)`,
		doc.ID, reader.ID, now, owner.ID, doc.ID, writer.ID, now, owner.ID); err != nil {
		t.Fatal(err)
	}
	for user, want := range map[string]string{owner.ID: DocRoleOwner, writer.ID: DocRoleEditor, reader.ID: DocRoleViewer, stranger.ID: ""} {
		if got := s.DocRole(user, doc.ID); got != want {
			t.Errorf("role of %s: got %q, want %q", user, got, want)
		}
	}
	if !s.IsDocShared(doc.ID) {
		t.Error("note with shares must count as shared")
	}
}

func TestBackfillConvertsFlatBlocksToTree(t *testing.T) {
	s, u := newSyncTestStore(t)
	doc, _ := s.CreateDocument(u.ID, "", "Alt", "📄", "", nil, nil, false)
	if _, err := s.db.Exec(`DELETE FROM blocks WHERE document_id = ?`, doc.ID); err != nil {
		t.Fatal(err)
	}
	// Rows as written by the old schema: only level and position
	for i, row := range [][2]interface{}{{"x", 0}, {"y", 1}, {"z", 1}, {"w", 0}} {
		if _, err := s.db.Exec(`INSERT INTO blocks (id, document_id, content, level, position, type) VALUES (?, ?, ?, ?, ?, 'bullet')`,
			row[0], doc.ID, row[0], row[1], (i+1)*1000); err != nil {
			t.Fatal(err)
		}
	}
	s.backfillBlockTree()
	got, _ := s.GetDocumentByID(u.ID, doc.ID)
	want := flatBlocks([3]interface{}{"x", 0, "x"}, [3]interface{}{"y", 1, "y"}, [3]interface{}{"z", 1, "z"}, [3]interface{}{"w", 0, "w"})
	sameOutline(t, got.Blocks, want)
}