package store

import (
	"context"
	"database/sql"
	"errors"
	"testing"

	"github.com/jackc/pgx/v5/pgconn"
)

func TestMapPostCreateError(t *testing.T) {
	t.Parallel()

	for _, code := range []string{"23503", "23505", "23514"} {
		err := mapPostCreateError(&pgconn.PgError{Code: code})
		if !errors.Is(err, ErrInvalidPost) {
			t.Errorf("code %s error = %v, want ErrInvalidPost", code, err)
		}
	}
	original := &pgconn.PgError{Code: "08006"}
	if err := mapPostCreateError(original); !errors.Is(err, original) {
		t.Errorf("unexpected database error was replaced: %v", err)
	}
}

func TestMemoryPostLifecycle(t *testing.T) {
	t.Parallel()

	ctx := context.Background()
	mem := NewMemory()
	homeowner := &User{Username: "homeowner", PasswordHash: "hash", Role: RoleUser}
	plumber := &User{Username: "plumber", PasswordHash: "hash", Role: RoleAdmin}
	voter := &User{Username: "voter", PasswordHash: "hash", Role: RoleUser}
	for _, user := range []*User{homeowner, plumber, voter} {
		if err := mem.CreateUser(ctx, user); err != nil {
			t.Fatal(err)
		}
	}

	root := &Post{
		ID:        "root",
		AuthorID:  homeowner.ID,
		Title:     "Leaky sink",
		Body:      "It drips.",
		City:      "Oakland",
		PostDate:  "2026-08-26",
		CreatedAt: "2026-08-26T08:00:00Z",
	}
	if err := mem.CreatePost(ctx, root); err != nil {
		t.Fatal(err)
	}

	rootID := root.ID
	later := &Post{
		ID:        "later",
		ParentID:  &rootID,
		AuthorID:  plumber.ID,
		Body:      "Is it a single-handle faucet?",
		CreatedAt: "2026-08-26T09:00:00Z",
	}
	earlier := &Post{
		ID:        "earlier",
		ParentID:  &rootID,
		AuthorID:  plumber.ID,
		Body:      "Can you share the model number?",
		CreatedAt: "2026-08-26T08:30:00Z",
	}
	if err := mem.CreatePost(ctx, later); err != nil {
		t.Fatal(err)
	}
	if err := mem.CreatePost(ctx, earlier); err != nil {
		t.Fatal(err)
	}

	laterID := later.ID
	nested := &Post{
		ID:        "nested",
		ParentID:  &laterID,
		AuthorID:  homeowner.ID,
		Body:      "Yes, it is.",
		CreatedAt: "2026-08-26T09:30:00Z",
	}
	if err := mem.CreatePost(ctx, nested); err != nil {
		t.Fatal(err)
	}

	thread, err := mem.GetPostThread(ctx, root.ID)
	if err != nil {
		t.Fatal(err)
	}
	if thread.AuthorName != homeowner.Name || thread.AuthorRole != RoleUser {
		t.Fatalf("root author = %q %q", thread.AuthorName, thread.AuthorRole)
	}
	if len(thread.Replies) != 2 ||
		thread.Replies[0].ID != earlier.ID ||
		thread.Replies[1].ID != later.ID {
		t.Fatalf("root replies are not oldest-first: %+v", thread.Replies)
	}
	if len(thread.Replies[1].Replies) != 1 || thread.Replies[1].Replies[0].ID != nested.ID {
		t.Fatalf("nested reply missing: %+v", thread.Replies[1].Replies)
	}

	otherParent := earlier.ID
	nested.ParentID = &otherParent
	nested.AuthorID = voter.ID
	nested.Body = "Yes—one handle."
	if err := mem.UpdatePost(ctx, nested); err != nil {
		t.Fatal(err)
	}
	saved, err := mem.GetPost(ctx, nested.ID)
	if err != nil {
		t.Fatal(err)
	}
	if saved.ParentID == nil || *saved.ParentID != later.ID {
		t.Fatalf("update changed parent to %+v", saved.ParentID)
	}
	if saved.AuthorID != homeowner.ID {
		t.Fatalf("update changed author to %q", saved.AuthorID)
	}
	if saved.Body != "Yes—one handle." || saved.UpdatedAt == saved.CreatedAt {
		t.Fatalf("body update not applied: %+v", saved)
	}

	if err := mem.VotePost(ctx, voter.ID, root.ID, 1); err != nil {
		t.Fatal(err)
	}
	roots, err := mem.ListRootPosts(ctx, root.PostDate, voter.ID)
	if err != nil {
		t.Fatal(err)
	}
	if len(roots) != 1 || roots[0].ID != root.ID {
		t.Fatalf("root list = %+v", roots)
	}
	if roots[0].Score != 1 || roots[0].UserVote != 1 || !roots[0].Answered {
		t.Fatalf("root annotations = %+v", roots[0])
	}
	if err := mem.VotePost(ctx, voter.ID, later.ID, 1); !errors.Is(err, ErrPostNotVotable) {
		t.Fatalf("reply vote error = %v", err)
	}
}

func TestMemoryPostValidation(t *testing.T) {
	t.Parallel()

	ctx := context.Background()
	mem := NewMemory()
	homeowner := &User{Username: "homeowner", PasswordHash: "hash", Role: RoleUser}
	if err := mem.CreateUser(ctx, homeowner); err != nil {
		t.Fatal(err)
	}

	tests := []struct {
		name string
		post *Post
	}{
		{
			name: "root without title",
			post: &Post{AuthorID: homeowner.ID, Body: "Body"},
		},
		{
			name: "empty parent",
			post: &Post{ParentID: ptr(""), AuthorID: homeowner.ID, Body: "Body"},
		},
		{
			name: "missing parent",
			post: &Post{ParentID: ptr("missing"), AuthorID: homeowner.ID, Body: "Body"},
		},
		{
			name: "reply with root fields",
			post: &Post{
				ParentID: ptr("missing"),
				AuthorID: homeowner.ID,
				Title:    "Not allowed",
				Body:     "Body",
			},
		},
	}
	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			if err := mem.CreatePost(ctx, test.post); !errors.Is(err, ErrInvalidPost) {
				t.Fatalf("error = %v, want ErrInvalidPost", err)
			}
		})
	}

	hidden := &Post{
		ID:       "hidden",
		AuthorID: homeowner.ID,
		Title:    "Hidden",
		Body:     "Body",
		PostDate: "2026-08-26",
		Hidden:   true,
	}
	if err := mem.CreatePost(ctx, hidden); err != nil {
		t.Fatal(err)
	}
	if err := mem.VotePost(ctx, homeowner.ID, hidden.ID, 1); !errors.Is(err, ErrPostNotVotable) {
		t.Fatalf("hidden root vote error = %v", err)
	}

	if _, err := mem.GetPostThread(ctx, "missing"); !errors.Is(err, sql.ErrNoRows) {
		t.Fatalf("missing thread error = %v", err)
	}
}

func ptr(value string) *string {
	return &value
}