package drugs

import (
	"github.com/antchfx/xmlquery"
	"os"
	"strconv"
)


func LoadDatabase(path string) XMLDrugsDatabase {
	f, err := os.Open(path)
	if err == nil {
		doc, err := xmlquery.Parse(f)
		if err == nil {
			return XMLDrugsDatabase{doc}
		}
	}
	return XMLDrugsDatabase{}
}


func populate_druginfo(node *xmlquery.Node) (di DrugInfo) {
	di.ID = node.SelectElement("drugbank-id").InnerText()
	di.Name = node.SelectElement("name").InnerText()
	di.HalfLife = node.SelectElement("half-life").InnerText()
	di.Description = node.SelectElement("description").InnerText()
	di.Indication = node.SelectElement("indication").InnerText()
	di.Pharmacodynamics = node.SelectElement("pharmacodynamics").InnerText()
	di.Toxicity = node.SelectElement("toxicity").InnerText()
	di.Absorption = node.SelectElement("absorption").InnerText()
	di.MechanismOfAction = node.SelectElement("mechanism-of-action").InnerText()

	interactions := node.SelectElement("drug-interactions").SelectElements("drug-interaction")
	for _, interaction := range interactions {
		di.Interactions = append(di.Interactions, DrugInteraction{interaction.SelectElement("drugbank-id").InnerText()})
	}

	di.DrugType = node.SelectAttr("type")

	classification := node.SelectElement("classification")
	if classification != nil {
		di.Classification = Classification{
			classification.SelectElement("description").InnerText(),
			classification.SelectElement("direct-parent").InnerText(),
			classification.SelectElement("kingdom").InnerText(),
			classification.SelectElement("superclass").InnerText(),
			classification.SelectElement("class").InnerText(),
			classification.SelectElement("subclass").InnerText()}
	}
	groups := node.SelectElement("groups").SelectElements("group")
	di.Groups = make(map[string]bool)
	for _, group := range groups {
		di.Groups[group.InnerText()] = true
	}

	salts := node.SelectElement("salts").SelectElements("salt")
	for _, salt := range salts {
		di.Salts = append(di.Salts, Salt{salt.SelectElement("drugbank-id").InnerText(),
											  salt.SelectElement("name").InnerText()})
	}

	pathways := node.SelectElement("pathways").SelectElements("pathway")
	for _, pathway := range pathways {
		pathwaysdrugs := []string{}
		drugs := pathway.SelectElement("drugs").SelectElements("drug")
		for _,drug := range drugs {
			pathwaysdrugs = append(pathwaysdrugs, drug.SelectElement("drugbank-id").InnerText())
		}
		di.Pathways = append(di.Pathways, PathWay{pathway.SelectElement("smpdb-id").InnerText(), pathwaysdrugs})
	}

	return
}


type XMLDrugsDatabase struct {
	root *xmlquery.Node
}

func (dd XMLDrugsDatabase) QueryDatabaseByID(ID string) (di DrugInfo) {
	result := xmlquery.FindOne(dd.root, "//drugbank/drug[./drugbank-id='"+ID+"']")
	return populate_druginfo(result)
}

func (dd XMLDrugsDatabase) QueryDatabaseByIndex(index int) (di DrugInfo) {
	result := xmlquery.FindOne(dd.root, "//drugbank/drug["+strconv.Itoa(index)+"]")
	return populate_druginfo(result)
}

func (dd XMLDrugsDatabase) QueryDatabaseByName(name string) (di DrugInfo) {
	result := xmlquery.Find(dd.root, "//drugbank/drug[./name='"+name+"']")
	if len(result) < 1 {
		return
	}
	return populate_druginfo(result[0])
}