package workbench

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"strings"

	platformid "aigateway.local/core/internal/platform/id"
	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgxpool"
)

type Service struct {
	pool     *pgxpool.Pool
	embedder Embedder
}

func NewService(pool *pgxpool.Pool) *Service { return &Service{pool: pool} }

// SetEmbedder 注入向量化器(M8 P2)。为 nil 时知识库退回纯 FTS,不生成 embedding。
func (s *Service) SetEmbedder(embedder Embedder) { s.embedder = embedder }

// Embedder 返回当前向量化器(可能为 nil)。
func (s *Service) Embedder() Embedder { return s.embedder }

func newUUID() (string, error) { return platformid.NewUUID() }

func emit(ctx context.Context, tx pgx.Tx, eventType, aggregateType, aggregateID, actorID string, values map[string]any) error {
	eventID, err := newUUID()
	if err != nil {
		return err
	}
	if values == nil {
		values = make(map[string]any)
	}
	values[aggregateType+"_id"] = aggregateID
	values["actor_id"] = actorID
	payload, err := json.Marshal(values)
	if err != nil {
		return err
	}
	_, err = tx.Exec(ctx, `INSERT INTO gateway.outbox_events(event_id,event_type,event_version,aggregate_type,aggregate_id,payload) VALUES($1,$2,1,$3,$4,$5)`, eventID, eventType, aggregateType, aggregateID, payload)
	return err
}

func normalizeStrings(values []string, maximum int) ([]string, error) {
	seen := make(map[string]struct{}, len(values))
	result := make([]string, 0, len(values))
	for _, value := range values {
		value = strings.TrimSpace(value)
		if value == "" {
			continue
		}
		if len(value) > 255 {
			return nil, errors.New("列表项过长")
		}
		if _, ok := seen[value]; ok {
			continue
		}
		seen[value] = struct{}{}
		result = append(result, value)
	}
	if len(result) > maximum {
		return nil, fmt.Errorf("列表最多允许 %d 项", maximum)
	}
	return result, nil
}

func mapNotFound(err error) error {
	if errors.Is(err, pgx.ErrNoRows) {
		return ErrNotFound
	}
	return err
}

func rollback(ctx context.Context, tx pgx.Tx) { _ = tx.Rollback(ctx) }