// Package store provides ...
package store

import (
	"context"
	"fmt"
	"sort"
	"sync"

	"github.com/eiblog/eiblog/pkg/model"
)

var (
	storeMu sync.RWMutex
	stores  = make(map[string]Driver)
)

// Store 存储后端
type Store interface {
	// LoadInsertAccount 读取或创建账户
	LoadInsertAccount(ctx context.Context, acct *model.Account) (*model.Account, error)
	// UpdateAccount 更新账户
	UpdateAccount(ctx context.Context, name string, fields map[string]interface{}) error

	// LoadInsertBlogger 读取或创建博客
	LoadInsertBlogger(ctx context.Context, blogger *model.Blogger) (*model.Blogger, error)
	// UpdateBlogger 更新博客
	UpdateBlogger(ctx context.Context, fields map[string]interface{}) error

	// InsertSeries 创建专题
	InsertSeries(ctx context.Context, series *model.Series) error
	// RemoveSeries 删除专题
	RemoveSeries(ctx context.Context, id int) error
	// UpdateSeries 更新专题
	UpdateSeries(ctx context.Context, id int, fields map[string]interface{}) error
	// LoadAllSeries 读取所有专题
	LoadAllSeries(ctx context.Context) (model.SortedSeries, error)

	// InsertArticle 创建文章
	InsertArticle(ctx context.Context, article *model.Article) error
	// RemoveArticle 硬删除文章
	RemoveArticle(ctx context.Context, id int) error
	// DeleteArticle 软删除文章,放入回收箱
	DeleteArticle(ctx context.Context, id int) error
	// CleanArticles 清理回收站文章
	CleanArticles(ctx context.Context) error
	// UpdateArticle 更新文章
	UpdateArticle(ctx context.Context, id int, fields map[string]interface{}) error
	// RecoverArticle 恢复文章到草稿
	RecoverArticle(ctx context.Context, id int) error
	// LoadAllArticle 读取所有文章
	LoadAllArticle(ctx context.Context) (model.SortedArticles, error)
	// LoadTrashArticles 读取回收箱
	LoadTrashArticles(ctx context.Context) (model.SortedArticles, error)
	// LoadDraftArticles 读取草稿箱
	LoadDraftArticles(ctx context.Context) (model.SortedArticles, error)
}

// Driver 存储驱动
type Driver interface {
	Init(source string) (Store, error)
}

// Register 注册驱动
func Register(name string, driver Driver) {
	storeMu.Lock()
	defer storeMu.Unlock()
	if driver == nil {
		panic("store: register driver is nil")
	}
	if _, dup := stores[name]; dup {
		panic("store: register called twice for driver " + name)
	}
	stores[name] = driver
}

// Drivers 获取所有
func Drivers() []string {
	storeMu.Lock()
	defer storeMu.Unlock()

	list := make([]string, 0, len(stores))
	for name := range stores {
		list = append(list, name)
	}
	sort.Strings(list)
	return list
}

// NewStore 新建存储
func NewStore(name string, source string) (Store, error) {
	storeMu.RLock()
	driver, ok := stores[name]
	storeMu.RUnlock()
	if !ok {
		return nil, fmt.Errorf("store: unknown driver %q (forgotten import?)", name)
	}

	return driver.Init(source)
}