// Package browser provides storage and operations for browser extension events.
// Events are staged in the database and can be accepted as worklog entries,
// attached to nodes, or dismissed.
package browser

import (
	"fmt"
	"log"
	"strings"
	"time"

	"verstak/internal/core/storage"
)

// Event represents a staged browser event from the database.
type Event struct {
	ID             string `json:"id"`
	DeviceID       string `json:"device_id"`
	Type           string `json:"type"`
	URL            string `json:"url"`
	Title          string `json:"title"`
	Domain         string `json:"domain"`
	ActiveSeconds  int    `json:"active_seconds"`
	TSStart        string `json:"ts_start"`
	TSEnd          string `json:"ts_end"`
	TS             string `json:"ts"`
	SelectedText   string `json:"selected_text"`
	Note           string `json:"note"`
	ScreenshotPath string `json:"screenshot_path"`
	Status         string `json:"status"` // pending, accepted, dismissed, attached
	CreatedAt      string `json:"created_at"`
	AcceptedAt     string `json:"accepted_at"`
	NodeID         string `json:"node_id"`
	WorklogID      string `json:"worklog_id"`
}

// Store provides CRUD for browser events.
type Store struct {
	db *storage.DB
}

// NewStore creates a new browser event store.
func NewStore(db *storage.DB) *Store {
	return &Store{db: db}
}

// InsertEvents bulk-inserts events into the staging table.
func (s *Store) InsertEvents(events []Event) (int, error) {
	if len(events) == 0 {
		return 0, nil
	}

	now := time.Now().UTC().Format(time.RFC3339)
	inserted := 0

	for _, ev := range events {
		res, err := s.db.Exec(`
			INSERT OR IGNORE INTO browser_events
				(id, device_id, type, url, title, domain, active_seconds,
				 ts_start, ts_end, ts, selected_text, note, created_at)
			VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
			ev.ID, ev.DeviceID, ev.Type, ev.URL, ev.Title, ev.Domain, ev.ActiveSeconds,
			ev.TSStart, ev.TSEnd, ev.TS, ev.SelectedText, ev.Note, now,
		)
		if err != nil {
			log.Printf("[browser] insert event %s: %v", ev.ID, err)
			continue
		}
		affected, _ := res.RowsAffected()
		if affected > 0 {
			inserted++
		}
	}

	return inserted, nil
}

// ListPending returns events with 'pending' status, newest first.
func (s *Store) ListPending(limit, offset int) ([]Event, error) {
	return s.listByStatus("pending", limit, offset)
}

// ListAll returns all events, newest first.
func (s *Store) ListAll(limit, offset int) ([]Event, error) {
	rows, err := s.db.Query(
		`SELECT id, device_id, type, url, title, domain, active_seconds,
		        ts_start, ts_end, ts, selected_text, note, screenshot_path,
		        status, created_at, accepted_at, node_id, worklog_id
		 FROM browser_events
		 ORDER BY created_at DESC
		 LIMIT ? OFFSET ?`, limit, offset)
	if err != nil {
		return nil, fmt.Errorf("list events: %w", err)
	}
	defer rows.Close()
	return scanEvents(rows)
}

// CountPending returns the number of pending events.
func (s *Store) CountPending() (int, error) {
	var count int
	err := s.db.QueryRow("SELECT COUNT(*) FROM browser_events WHERE status = 'pending'").Scan(&count)
	return count, err
}

// Accept marks an event as accepted, optionally linking it to a worklog entry.
func (s *Store) Accept(id, worklogID string) error {
	now := time.Now().UTC().Format(time.RFC3339)
	_, err := s.db.Exec(
		"UPDATE browser_events SET status = 'accepted', accepted_at = ?, worklog_id = ? WHERE id = ?",
		now, worklogID, id)
	return err
}

// Attach marks an event as attached to a node.
func (s *Store) Attach(id, nodeID string) error {
	now := time.Now().UTC().Format(time.RFC3339)
	_, err := s.db.Exec(
		"UPDATE browser_events SET status = 'attached', accepted_at = ?, node_id = ? WHERE id = ?",
		now, nodeID, id)
	return err
}

// Dismiss marks an event as dismissed.
func (s *Store) Dismiss(id string) error {
	_, err := s.db.Exec("UPDATE browser_events SET status = 'dismissed' WHERE id = ?", id)
	return err
}

// Get returns a single event by ID.
func (s *Store) Get(id string) (*Event, error) {
	row := s.db.QueryRow(
		`SELECT id, device_id, type, url, title, domain, active_seconds,
		        ts_start, ts_end, ts, selected_text, note, screenshot_path,
		        status, created_at, accepted_at, node_id, worklog_id
		 FROM browser_events WHERE id = ?`, id)

	var ev Event
	err := row.Scan(
		&ev.ID, &ev.DeviceID, &ev.Type, &ev.URL, &ev.Title, &ev.Domain, &ev.ActiveSeconds,
		&ev.TSStart, &ev.TSEnd, &ev.TS, &ev.SelectedText, &ev.Note, &ev.ScreenshotPath,
		&ev.Status, &ev.CreatedAt, &ev.AcceptedAt, &ev.NodeID, &ev.WorklogID,
	)
	if err != nil {
		return nil, fmt.Errorf("get event %s: %w", id, err)
	}
	return &ev, nil
}

// --- internals ---

func (s *Store) listByStatus(status string, limit, offset int) ([]Event, error) {
	rows, err := s.db.Query(
		`SELECT id, device_id, type, url, title, domain, active_seconds,
		        ts_start, ts_end, ts, selected_text, note, screenshot_path,
		        status, created_at, accepted_at, node_id, worklog_id
		 FROM browser_events
		 WHERE status = ?
		 ORDER BY created_at DESC
		 LIMIT ? OFFSET ?`, status, limit, offset)
	if err != nil {
		return nil, fmt.Errorf("list %s events: %w", status, err)
	}
	defer rows.Close()
	return scanEvents(rows)
}

func scanEvents(rows interface {
	Next() bool
	Scan(dest ...interface{}) error
	Close() error
}) ([]Event, error) {
	var events []Event
	for rows.Next() {
		var ev Event
		err := rows.Scan(
			&ev.ID, &ev.DeviceID, &ev.Type, &ev.URL, &ev.Title, &ev.Domain, &ev.ActiveSeconds,
			&ev.TSStart, &ev.TSEnd, &ev.TS, &ev.SelectedText, &ev.Note, &ev.ScreenshotPath,
			&ev.Status, &ev.CreatedAt, &ev.AcceptedAt, &ev.NodeID, &ev.WorklogID,
		)
		if err != nil {
			return nil, fmt.Errorf("scan event: %w", err)
		}
		events = append(events, ev)
	}
	return events, rows.Close()
}

// String returns a short summary for logging.
func (e *Event) String() string {
	parts := []string{e.Type}
	if e.Domain != "" {
		parts = append(parts, e.Domain)
	}
	if e.Title != "" {
		parts = append(parts, truncate(e.Title, 40))
	}
	if e.ActiveSeconds > 0 {
		parts = append(parts, fmt.Sprintf("%ds", e.ActiveSeconds))
	}
	return strings.Join(parts, " | ")
}

func truncate(s string, n int) string {
	if len(s) <= n {
		return s
	}
	return s[:n] + "..."
}