package db

import (
	"git.giftfish.de/ston1th/gowiki/pkg/core"
	"git.giftfish.de/ston1th/gowiki/pkg/render"
	"git.giftfish.de/ston1th/gowiki/pkg/util"
	"github.com/boltdb/bolt"
)

var (
	errPageNotFound      = dbErr("page not found")
	errInvalidPermission = dbErr("invalid permission")
	errPrivateWikiPage   = dbErr("private wiki pages are not allowed")
)

func (bs *BoltStore) GetPage(title, username string) (p *core.Page, err error) {
	p = bs.cache.Get(title)
	if p == nil {
		p = new(core.Page)
		err = bs.db.View(func(tx *bolt.Tx) error {
			v := tx.Bucket([]byte(pageTable)).Get([]byte(title))
			if v == nil {
				return errPageNotFound
			}
			return bs.Unmarshal(v, p)
		})
		if err != nil {
			return
		}
		bs.cache.Add(title, p)
	}
	if !core.ReadPerm(username, p) {
		err = errPageNotFound
	}
	return
}

// TODO access db not cache
func (bs *BoltStore) pageExists(title, username string) (p *core.Page, err error) {
	p, err = bs.GetPage(title, username)
	return
}

func (bs *BoltStore) CreatePage(title, section, markdown, username string, perm int) (page *core.Page, err error) {
	p := core.ParsePerm(perm)
	if p == core.Invalid {
		err = errInvalidPermission
		return
	}
	if section == wikiSection && p == core.Private {
		err = errPrivateWikiPage
		return
	}
	st := util.StoreTitle(section, title)
	if _, err = bs.pageExists(st, username); err != nil {
		return
	}

	page = &core.Page{
		Title:    title,
		Markdown: markdown,
		Created:  created(username),
		Owner:    username,
		Perm:     p,
	}
	search := render.Render(page)

	err = bs.db.Update(func(tx *bolt.Tx) error {
		v, err := bs.Marshal(page)
		if err != nil {
			return err
		}
		return tx.Bucket([]byte(pageTable)).Put([]byte(st), v)
	})
	if err != nil {
		return
	}

	err = bs.index.Add(title, st, search)
	if err != nil {
		return
	}
	bs.cache.Add(st, page)
	return
}

func (bs *BoltStore) UpdatePage(title, section, markdown, username string, perm int) (page *core.Page, err error) {
	p := core.ParsePerm(perm)
	if p == core.Invalid {
		err = errInvalidPermission
		return
	}
	if section == wikiSection && p == core.Private {
		err = errPrivateWikiPage
		return
	}
	st := util.StoreTitle(section, title)
	page, err = bs.pageExists(st, username)
	if err != nil {
		return
	}

	page.Markdown = markdown
	page.Updated = created(username)
	page.Perm = p
	search := render.Render(page)

	err = bs.db.Update(func(tx *bolt.Tx) error {
		v, err := bs.Marshal(page)
		if err != nil {
			return err
		}
		return tx.Bucket([]byte(pageTable)).Put([]byte(st), v)
	})
	if err != nil {
		return
	}

	err = bs.index.Add(title, st, search)
	if err != nil {
		return
	}
	bs.cache.Add(st, page)
	return
}

func (bs *BoltStore) DeletePage(title, section, username string) error {
	st := util.StoreTitle(section, title)
	if _, err := bs.pageExists(st, username); err != nil {
		return err
	}
	if err := bs.db.Update(func(tx *bolt.Tx) error {
		return tx.Bucket([]byte(pageTable)).Delete([]byte(st))
	}); err != nil {
		return err
	}
	return bs.index.Delete(st)
}