package postgres

import (
	"context"
	"database/sql"
	"encoding/json"

	"git.gobha.me/xcaliber/chat-switchboard/store"
)

type SurfaceRegistryStore struct{}

func NewSurfaceRegistryStore() *SurfaceRegistryStore { return &SurfaceRegistryStore{} }

// Seed upserts a core surface. Called at startup by the page engine
// to ensure core surfaces exist in the registry. Does NOT overwrite
// the enabled state if the row already exists (admin toggle survives restart).
func (s *SurfaceRegistryStore) Seed(ctx context.Context, id, title, source string, manifest map[string]any) error {
	manifestJSON := ToJSON(manifest)
	_, err := DB.ExecContext(ctx, `
		INSERT INTO surface_registry (id, title, source, manifest, enabled, installed_at, updated_at)
		VALUES ($1, $2, $3, $4, true, NOW(), NOW())
		ON CONFLICT (id) DO UPDATE SET
			title = $2,
			manifest = $4,
			source = $3,
			updated_at = NOW()`,
		// Note: ON CONFLICT does NOT update 'enabled' — preserves admin toggle
		id, title, source, manifestJSON)
	return err
}

func (s *SurfaceRegistryStore) List(ctx context.Context) ([]store.SurfaceRegistration, error) {
	rows, err := DB.QueryContext(ctx,
		`SELECT id, title, manifest, enabled, source, installed_at, updated_at
		 FROM surface_registry ORDER BY source, title`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var surfaces []store.SurfaceRegistration
	for rows.Next() {
		var sr store.SurfaceRegistration
		var manifestJSON []byte
		if err := rows.Scan(&sr.ID, &sr.Title, &manifestJSON, &sr.Enabled, &sr.Source, &sr.InstalledAt, &sr.UpdatedAt); err != nil {
			continue
		}
		json.Unmarshal(manifestJSON, &sr.Manifest)
		surfaces = append(surfaces, sr)
	}
	return surfaces, rows.Err()
}

func (s *SurfaceRegistryStore) Get(ctx context.Context, id string) (*store.SurfaceRegistration, error) {
	var sr store.SurfaceRegistration
	var manifestJSON []byte
	err := DB.QueryRowContext(ctx,
		`SELECT id, title, manifest, enabled, source, installed_at, updated_at
		 FROM surface_registry WHERE id = $1`, id).
		Scan(&sr.ID, &sr.Title, &manifestJSON, &sr.Enabled, &sr.Source, &sr.InstalledAt, &sr.UpdatedAt)
	if err == sql.ErrNoRows {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}
	json.Unmarshal(manifestJSON, &sr.Manifest)
	return &sr, nil
}

func (s *SurfaceRegistryStore) SetEnabled(ctx context.Context, id string, enabled bool) error {
	result, err := DB.ExecContext(ctx,
		`UPDATE surface_registry SET enabled = $2, updated_at = NOW() WHERE id = $1`,
		id, enabled)
	if err != nil {
		return err
	}
	affected, _ := result.RowsAffected()
	if affected == 0 {
		return sql.ErrNoRows
	}
	return nil
}

func (s *SurfaceRegistryStore) Delete(ctx context.Context, id string) error {
	// Only allow deleting extension surfaces, not core
	result, err := DB.ExecContext(ctx,
		`DELETE FROM surface_registry WHERE id = $1 AND source = 'extension'`, id)
	if err != nil {
		return err
	}
	affected, _ := result.RowsAffected()
	if affected == 0 {
		return sql.ErrNoRows
	}
	return nil
}

func (s *SurfaceRegistryStore) ListEnabled(ctx context.Context) ([]string, error) {
	rows, err := DB.QueryContext(ctx,
		`SELECT id FROM surface_registry WHERE enabled = true ORDER BY title`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var ids []string
	for rows.Next() {
		var id string
		if err := rows.Scan(&id); err != nil {
			continue
		}
		ids = append(ids, id)
	}
	return ids, rows.Err()
}