package model

import (
	"context"
	"sync"

	"spark-server/internal/module/message/entity"
	"spark-server/internal/pkg/errs"
)

// MemoryRepo is an in-process message store for tests and empty-DSN bring-up.
type MemoryRepo struct {
	mu   sync.Mutex
	byID map[int64]*entity.Message
}

func NewMemoryRepo() *MemoryRepo {
	return &MemoryRepo{byID: make(map[int64]*entity.Message)}
}

func (m *MemoryRepo) Create(_ context.Context, message *entity.Message) error {
	if message == nil || message.ID <= 0 {
		return errs.ErrInvalidArgument
	}
	m.mu.Lock()
	defer m.mu.Unlock()
	if _, ok := m.byID[message.ID]; ok {
		return errs.ErrDuplicate
	}
	cp := *message
	if cp.Content != nil {
		cp.Content = append([]byte(nil), message.Content...)
	}
	m.byID[message.ID] = &cp
	return nil
}

func (m *MemoryRepo) GetByID(_ context.Context, id int64) (*entity.Message, error) {
	m.mu.Lock()
	defer m.mu.Unlock()
	row, ok := m.byID[id]
	if !ok {
		return nil, errs.ErrNotFound
	}
	cp := *row
	if cp.Content != nil {
		cp.Content = append([]byte(nil), row.Content...)
	}
	return &cp, nil
}

func (m *MemoryRepo) All() []*entity.Message {
	m.mu.Lock()
	defer m.mu.Unlock()
	out := make([]*entity.Message, 0, len(m.byID))
	for _, row := range m.byID {
		cp := *row
		if cp.Content != nil {
			cp.Content = append([]byte(nil), row.Content...)
		}
		out = append(out, &cp)
	}
	return out
}