package story

import (
	"context"
	"database/sql"
	"fmt"
	"strings"
	"testing"
	"time"

	v1 "git.tipsy.codes/charles/webstory/pkg/api/webstory/v1"
	"git.tipsy.codes/charles/webstory/pkg/database/schema"
	embeddedpostgres "github.com/fergusstrange/embedded-postgres"
	"github.com/lib/pq"
	"google.golang.org/protobuf/types/known/timestamppb"
)

func TestStoryTranslator_FromAPI(t *testing.T) {
	now := time.Now()
	tests := []struct {
		name      string
		apiStory  *v1.Story
		expectErr bool
		errMsg    string
		expectID  int64
		checkFunc func(*DBStory) error
	}{
		{
			name:      "nil story returns error",
			apiStory:  nil,
			expectErr: true,
			errMsg:    "api story cannot be nil",
		},
		{
			name: "minimal valid story creates translator correctly",
			apiStory: &v1.Story{
				StoryId: "abc123",
				Title:   "Test Story",
			},
			expectErr: false,
			expectID:  0,
			checkFunc: func(s *DBStory) error {
				if s.StoryID != "abc123" {
					return fmt.Errorf("expected StoryID abc123, got %s", s.StoryID)
				}
				if s.Title != "Test Story" {
					return fmt.Errorf("expected Title Test Story, got %s", s.Title)
				}
				return nil
			},
		},
		{
			name: "story with all fields converts correctly",
			apiStory: &v1.Story{
				Name:        "stories/my-story-1",
				StoryId:     "my-story-1",
				Title:       "My Story Title",
				Content:     "This is the story content",
				Description: "A wonderful story",
				Labels:      []string{"fiction", "adventure"},
				CreateTime:  timestamppb.New(now),
				UpdateTime:  timestamppb.New(now),
				Etag:        "etag-123",
			},
			expectErr: false,
			expectID:  0,
			checkFunc: func(s *DBStory) error {
				if s.StoryID != "my-story-1" {
					return fmt.Errorf("expected StoryID my-story-1, got %s", s.StoryID)
				}
				if s.Title != "My Story Title" {
					return fmt.Errorf("expected Title My Story Title, got %s", s.Title)
				}
				if s.Content != "This is the story content" {
					return fmt.Errorf("expected Content, got %s", s.Content)
				}
				if s.Description != "A wonderful story" {
					return fmt.Errorf("expected Description, got %s", s.Description)
				}
				if len(s.Labels) != 2 || s.Labels[0] != "fiction" || s.Labels[1] != "adventure" {
					return fmt.Errorf("expected Labels [fiction adventure], got %v", s.Labels)
				}
				if s.Etag != "etag-123" {
					return fmt.Errorf("expected Etag etag-123, got %s", s.Etag)
				}
				return nil
			},
		},
		{
			name: "nil labels converted to empty slice",
			apiStory: &v1.Story{
				StoryId: "test1",
				Title:   "Test",
				Labels:  nil,
			},
			expectErr: false,
			expectID:  0,
			checkFunc: func(s *DBStory) error {
				if s.Labels == nil {
					return fmt.Errorf("expected non-nil Labels slice, got nil")
				}
				return nil
			},
		},
		{
			name: "empty labels converted to empty slice",
			apiStory: &v1.Story{
				StoryId: "test2",
				Title:   "Test",
				Labels:  []string{},
			},
			expectErr: false,
			expectID:  0,
			checkFunc: func(s *DBStory) error {
				if s.Labels == nil {
					return fmt.Errorf("expected non-nil Labels slice, got nil")
				}
				if len(s.Labels) != 0 {
					return fmt.Errorf("expected empty Labels slice, got %v", s.Labels)
				}
				return nil
			},
		},
		{
			name: "missing title returns error",
			apiStory: &v1.Story{
				StoryId: "test3",
			},
			expectErr: true,
			errMsg:    "title is required",
		},
		{
			name: "invalid story_id short returns error",
			apiStory: &v1.Story{
				StoryId: "ab",
				Title:   "Test",
			},
			expectErr: true,
			errMsg:    "invalid story_id format",
		},
		{
			name: "invalid story_id uppercase returns error",
			apiStory: &v1.Story{
				StoryId: "ABC123",
				Title:   "Test",
			},
			expectErr: true,
			errMsg:    "invalid story_id format",
		},
		{
			name: "invalid story_id starts with number returns error",
			apiStory: &v1.Story{
				StoryId: "1abc",
				Title:   "Test",
			},
			expectErr: true,
			errMsg:    "invalid story_id format",
		},
		{
			name: "valid story_id with hyphens and numbers",
			apiStory: &v1.Story{
				StoryId: "my-awesome-story-123",
				Title:   "Test",
			},
			expectErr: false,
			expectID:  0,
			checkFunc: func(s *DBStory) error {
				if s.StoryID != "my-awesome-story-123" {
					return fmt.Errorf("expected StoryID my-awesome-story-123, got %s", s.StoryID)
				}
				return nil
			},
		},
		{
			name: "story_id auto-generated from name if not provided",
			apiStory: &v1.Story{
				StoryId: "auto-gen",
				Title:   "Test",
				Name:    "stories/auto-gen",
			},
			expectErr: false,
			expectID:  0,
			checkFunc: func(s *DBStory) error {
				if s.StoryID != "auto-gen" {
					return fmt.Errorf("expected StoryID auto-gen, got %s", s.StoryID)
				}
				return nil
			},
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			trans := NewStoryTranslator()
			result, err := trans.FromAPI(tt.apiStory)

			if tt.expectErr {
				if err == nil {
					t.Fatalf("expected error but got nil")
				}
				if tt.errMsg != "" && !strings.Contains(err.Error(), tt.errMsg) {
					t.Errorf("expected error containing '%s' but got '%s'", tt.errMsg, err.Error())
				}
				return
			}

			if err != nil {
				t.Fatalf("unexpected error: %v", err)
			}

			if result == nil {
				t.Fatalf("expected non-nil result")
			}

			if result.ID != tt.expectID {
				t.Errorf("expected ID %d but got %d", tt.expectID, result.ID)
			}

			if tt.checkFunc != nil {
				if err := tt.checkFunc(result); err != nil {
					t.Errorf("check failed: %v", err)
				}
			}
		})
	}
}

func TestStoryTranslator_ToAPI(t *testing.T) {

	now := time.Now()

	tests := []struct {
		name      string
		dbStory   *DBStory
		expectErr bool
		checkFunc func(*v1.Story) error
	}{
		{
			name:      "nil dbStory returns nil",
			dbStory:   nil,
			expectErr: false,
			checkFunc: func(s *v1.Story) error {
				if s != nil {
					return fmt.Errorf("expected nil, got %v", s)
				}
				return nil
			},
		},
		{
			name: "minimal story converts correctly",
			dbStory: &DBStory{
				ID:        1,
				StoryID:   "test-story",
				Title:     "Test Title",
				CreatedAt: now,
				UpdatedAt: now,
			},
			expectErr: false,
			checkFunc: func(s *v1.Story) error {
				if s.GetName() != "stories/test-story" {
					return fmt.Errorf("expected Name stories/test-story, got %s", s.GetName())
				}
				if s.GetStoryId() != "test-story" {
					return fmt.Errorf("expected StoryId test-story, got %s", s.GetStoryId())
				}
				if s.GetTitle() != "Test Title" {
					return fmt.Errorf("expected Title Test Title, got %s", s.GetTitle())
				}
				return nil
			},
		},
		{
			name: "story with all fields converts correctly",
			dbStory: &DBStory{
				ID:          1,
				StoryID:     "full-story",
				Title:       "Full Title",
				Content:     "Full Content",
				Description: "Full Description",
				Labels:      []string{"label1", "label2"},
				CreatedAt:   now,
				UpdatedAt:   now,
				Etag:        "test-etag",
			},
			expectErr: false,
			checkFunc: func(s *v1.Story) error {
				if s.GetName() != "stories/full-story" {
					return fmt.Errorf("expected Name stories/full-story, got %s", s.GetName())
				}
				if s.Etag != "test-etag" {
					return fmt.Errorf("expected Etag test-etag, got %s", s.Etag)
				}
				if len(s.GetLabels()) != 2 {
					return fmt.Errorf("expected 2 labels, got %d", len(s.GetLabels()))
				}
				return nil
			},
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			trans := NewStoryTranslator()
			result := trans.ToAPI(tt.dbStory)

			if tt.expectErr {
				if result != nil {
					t.Fatalf("expected nil result but got %v", result)
				}
				return
			}

			if tt.checkFunc != nil {
				if err := tt.checkFunc(result); err != nil {
					t.Errorf("check failed: %v", err)
				}
			}
		})
	}
}

func TestDBStory_Validate(t *testing.T) {
	tests := []struct {
		name      string
		story     *DBStory
		expectErr bool
		errMsg    string
	}{
		{
			name: "empty story_id returns error",
			story: &DBStory{
				StoryID: "",
				Title:   "Test",
			},
			expectErr: true,
			errMsg:    "story_id is required",
		},
		{
			name: "invalid story_id format returns error",
			story: &DBStory{
				StoryID: "INVALID",
				Title:   "Test",
			},
			expectErr: true,
			errMsg:    "invalid story_id format",
		},
		{
			name: "empty title returns error",
			story: &DBStory{
				StoryID: "valid-story-1",
				Title:   "",
			},
			expectErr: true,
			errMsg:    "title is required",
		},
		{
			name: "valid story passes validation",
			story: &DBStory{
				StoryID: "valid-story-1",
				Title:   "Valid Title",
			},
			expectErr: false,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := tt.story.Validate()

			if tt.expectErr {
				if err == nil {
					t.Fatalf("expected error but got nil")
				}
				if tt.errMsg != "" && !strings.Contains(err.Error(), tt.errMsg) {
					t.Errorf("expected error containing '%s' but got '%s'", tt.errMsg, err.Error())
				}
				return
			}

			if err != nil {
				t.Fatalf("unexpected error: %v", err)
			}
		})
	}
}

func TestDBStory_Save(t *testing.T) {
	// Set up embedded postgres for testing
	server := embeddedpostgres.NewDatabase(embeddedpostgres.DefaultConfig().Port(5432))
	err := server.Start()
	if err != nil {
		t.Fatalf("failed to start embedded postgres: %v", err)
	}
	defer func() {
		if err := server.Stop(); err != nil {
			t.Errorf("failed to stop embedded postgres: %v", err)
		}
	}()

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	db, err := sql.Open("postgres", "postgres://postgres:postgres@127.0.0.1:5432/postgres?sslmode=disable")
	if err != nil {
		t.Fatalf("failed to connect to database: %v", err)
	}
	defer db.Close()

	// Run migrations
	_, err = db.ExecContext(ctx, string(schema.Bytes))
	if err != nil {
		t.Fatalf("failed to run schema: %v", err)
	}

	tests := []struct {
		name      string
		setupFunc func() *DBStory
		expectErr bool
		checkFunc func(*testing.T, *sql.DB, *DBStory) error
	}{
		{
			name: "insert new story successfully",
			setupFunc: func() *DBStory {
				return &DBStory{
					StoryID: "insert-test-1",
					Title:   "Insert Test Story",
					Content: "Test content",
					Labels:  []string{"test", "insert"},
				}
			},
			expectErr: false,
			checkFunc: func(t *testing.T, db *sql.DB, story *DBStory) error {
				if story.ID == 0 {
					return fmt.Errorf("expected non-zero ID after insert, got 0")
				}
				if story.CreatedAt.IsZero() {
					return fmt.Errorf("expected non-zero CreatedAt")
				}
				if story.UpdatedAt.IsZero() {
					return fmt.Errorf("expected non-zero UpdatedAt")
				}
				if story.Etag == "" {
					return fmt.Errorf("expected non-empty etag")
				}

				// Verify in database
				var dbStory DBStory
				var labels pq.StringArray
				err := db.QueryRow(`
						SELECT id, story_id, title, content, labels, created_at, updated_at, etag
						FROM stories WHERE id = $1`,
					story.ID).Scan(
					&dbStory.ID, &dbStory.StoryID, &dbStory.Title, &dbStory.Content,
					&labels, &dbStory.CreatedAt, &dbStory.UpdatedAt, &dbStory.Etag,
				)
				if err != nil {
					return fmt.Errorf("failed to query inserted story: %w", err)
				}
				dbStory.Labels = labels
				if dbStory.StoryID != story.StoryID {
					return fmt.Errorf("story_id mismatch: expected %s, got %s", story.StoryID, dbStory.StoryID)
				}
				if dbStory.Title != story.Title {
					return fmt.Errorf("title mismatch: expected %s, got %s", story.Title, dbStory.Title)
				}
				return nil
			},
		},
		{
			name: "insert new story with etag provided",
			setupFunc: func() *DBStory {
				return &DBStory{
					StoryID: "insert-test-2",
					Title:   "Insert Test with Etag",
					Etag:    "custom-etag-123",
				}
			},
			expectErr: false,
			checkFunc: func(t *testing.T, db *sql.DB, story *DBStory) error {
				// Verify etag was set (even if custom provided, DB may override)
				var dbStory DBStory
				err := db.QueryRow(`SELECT etag FROM stories WHERE story_id = $1`, "insert-test-2").Scan(&dbStory.Etag)
				if err != nil {
					return fmt.Errorf("failed to query story: %w", err)
				}
				if dbStory.Etag == "" {
					return fmt.Errorf("expected non-empty etag in database")
				}
				return nil
			},
		},
		{
			name: "insert new story with all fields",
			setupFunc: func() *DBStory {
				return &DBStory{
					StoryID:     "insert-test-3",
					Title:       "Full Story",
					Content:     "Full content here",
					Description: "Full description",
					Labels:      []string{"tag1", "tag2", "tag3"},
				}
			},
			expectErr: false,
			checkFunc: func(t *testing.T, db *sql.DB, story *DBStory) error {
				var dbStory DBStory
				var labels pq.StringArray
				err := db.QueryRow(`
						SELECT id, story_id, title, content, description, labels, created_at, updated_at, etag
						FROM stories WHERE story_id = $1`,
					"insert-test-3").Scan(
					&dbStory.ID, &dbStory.StoryID, &dbStory.Title, &dbStory.Content,
					&dbStory.Description, &labels, &dbStory.CreatedAt,
					&dbStory.UpdatedAt, &dbStory.Etag,
				)
				if err != nil {
					return fmt.Errorf("failed to query inserted story: %w", err)
				}
				dbStory.Labels = []string(labels)
				if dbStory.Description != "Full description" {
					return fmt.Errorf("description mismatch")
				}
				return nil
			},
		},
		{
			name: "update existing story successfully",
			setupFunc: func() *DBStory {
				// First create the story
				newStory := &DBStory{
					StoryID: "update-test-1",
					Title:   "Original Title",
					Content: "Original content",
				}
				if err := newStory.Save(db); err != nil {
					t.Fatalf("failed to insert story for update test: %v", err)
				}
				// Now update it
				newStory.ID = newStory.ID
				newStory.Title = "Updated Title"
				newStory.Content = "Updated content"
				return newStory
			},
			expectErr: false,
			checkFunc: func(t *testing.T, db *sql.DB, story *DBStory) error {
				if story.Title != "Updated Title" {
					return fmt.Errorf("expected title to be 'Updated Title', got %s", story.Title)
				}
				if story.Content != "Updated content" {
					return fmt.Errorf("expected content to be 'Updated content', got %s", story.Content)
				}

				// Verify in database
				var dbStory DBStory
				err := db.QueryRow(`
					SELECT title, content FROM stories WHERE id = $1`,
					story.ID).Scan(&dbStory.Title, &dbStory.Content)
				if err != nil {
					return fmt.Errorf("failed to query updated story: %w", err)
				}
				if dbStory.Title != "Updated Title" {
					return fmt.Errorf("title mismatch in DB: expected 'Updated Title', got %s", dbStory.Title)
				}
				if dbStory.Content != "Updated content" {
					return fmt.Errorf("content mismatch in DB")
				}
				return nil
			},
		},
		{
			name: "update with labels changes",
			setupFunc: func() *DBStory {
				// First create
				newStory := &DBStory{
					StoryID: "update-test-2",
					Title:   "Label Update Test",
					Labels:  []string{"old-tag"},
				}
				if err := newStory.Save(db); err != nil {
					t.Fatalf("failed to insert story for label update test: %v", err)
				}
				// Update
				newStory.ID = newStory.ID
				newStory.Labels = []string{"new-tag-1", "new-tag-2"}
				return newStory
			},
			expectErr: false,
			checkFunc: func(t *testing.T, db *sql.DB, story *DBStory) error {
				var dbLabels pq.StringArray
				err := db.QueryRow(`SELECT labels FROM stories WHERE id = $1`, story.ID).Scan(&dbLabels)
				if err != nil {
					return fmt.Errorf("failed to query labels: %w", err)
				}
				if len(dbLabels) != 2 {
					return fmt.Errorf("expected 2 labels, got %d", len(dbLabels))
				}
				return nil
			},
		},
		{
			name: "insert with invalid story_id fails",
			setupFunc: func() *DBStory {
				return &DBStory{
					StoryID: "INVALID",
					Title:   "Should Fail",
				}
			},
			expectErr: true,
			checkFunc: func(t *testing.T, db *sql.DB, story *DBStory) error {
				return nil
			},
		},
		{
			name: "insert with empty title fails",
			setupFunc: func() *DBStory {
				return &DBStory{
					StoryID: "empty-title-test",
					Title:   "",
				}
			},
			expectErr: true,
			checkFunc: func(t *testing.T, db *sql.DB, story *DBStory) error {
				return nil
			},
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			story := tt.setupFunc()

			err := story.Save(db)

			if tt.expectErr {
				if err == nil {
					t.Fatalf("expected error but got nil")
				}
				return
			}

			if err != nil {
				t.Fatalf("unexpected error: %v", err)
			}

			if tt.checkFunc != nil {
				if err := tt.checkFunc(t, db, story); err != nil {
					t.Errorf("check failed: %v", err)
				}
			}
		})
	}
}