// SiYuan - Build Your Eternal Digital Garden
// Copyright (c) 2020-present, b3log.org
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

package treenode

import (
	"crypto/sha256"
	"fmt"
	"path"
	"sort"
	"strings"

	"github.com/88250/gulu"
	"github.com/88250/lute"
	"github.com/88250/lute/ast"
	"github.com/88250/lute/parse"
	util2 "github.com/88250/lute/util"
	"github.com/siyuan-note/siyuan/kernel/util"
)

func NodeHash(node *ast.Node, tree *parse.Tree, luteEngine *lute.Lute) string {
	ialArray := node.KramdownIAL
	sort.Slice(ialArray, func(i, j int) bool {
		return ialArray[i][0] < ialArray[j][0]
	})
	ial := parse.IAL2Tokens(ialArray)
	var md string
	if ast.NodeDocument != node.Type {
		md = FormatNode(node, luteEngine)
	}
	hpath := tree.HPath
	data := tree.Path + hpath + string(ial) + md
	return fmt.Sprintf("%x", sha256.Sum256(gulu.Str.ToBytes(data)))[:7]
}

func TreeRoot(node *ast.Node) *ast.Node {
	for p := node; nil != p; p = p.Parent {
		if ast.NodeDocument == p.Type {
			return p
		}
	}
	return &ast.Node{Type: ast.NodeDocument}
}

func NewTree(boxID, p, hp, title string) *parse.Tree {
	id := strings.TrimSuffix(path.Base(p), ".sy")
	root := &ast.Node{Type: ast.NodeDocument, ID: id}
	root.SetIALAttr("title", title)
	root.SetIALAttr("id", id)
	root.SetIALAttr("updated", util.TimeFromID(id))
	ret := &parse.Tree{Root: root}
	ret.Box = boxID
	ret.Path = p
	ret.HPath = hp
	newPara := &ast.Node{Type: ast.NodeParagraph, ID: ast.NewNodeID()}
	newPara.SetIALAttr("id", newPara.ID)
	newPara.SetIALAttr("updated", util.TimeFromID(newPara.ID))
	ret.Root.AppendChild(newPara)
	return ret
}

func IsEmptyBlockIAL(n *ast.Node) bool {
	if ast.NodeKramdownBlockIAL != n.Type {
		return false
	}

	if util2.IsDocIAL(n.Tokens) {
		return false
	}

	if nil != n.Previous {
		if ast.NodeKramdownBlockIAL == n.Previous.Type {
			return true
		}
		return false
	}
	return true
}

func IALStr(n *ast.Node) string {
	if 1 > len(n.KramdownIAL) {
		return ""
	}
	return string(parse.IAL2Tokens(n.KramdownIAL))
}