package inventaire

import (
	"encoding/json"
	"errors"

	"git.artlef.fr/PersonalLibraryManager/internal/callapiutils"
)

type InventaireBookResult struct {
	ID          string
	Lang        string
	Title       string
	Description string
	Author      *InventaireAuthorResult
}

type InventaireAuthorResult struct {
	ID          string
	Name        string
	Description string
}

func (i *InventaireBookResult) UnmarshalJSON(b []byte) error {
	var parsed struct {
		Entities map[string]json.RawMessage
	}
	err := json.Unmarshal(b, &parsed)
	if err != nil {
		return err
	}

	for _, entity := range parsed.Entities {

		var inventaireEntity struct {
			WdId         string                     `json:"wdId"`
			Type         string                     `json:"type"`
			Labels       map[string]json.RawMessage `json:"labels"`
			Descriptions map[string]json.RawMessage `json:"descriptions"`
		}

		err := json.Unmarshal(entity, &inventaireEntity)
		if err != nil {
			return err
		}
		if inventaireEntity.WdId == i.ID {
			title, err := findLangageField(inventaireEntity.Labels, i.Lang)
			if err != nil {
				return err
			}
			i.Title = title
			description, err := findLangageField(inventaireEntity.Descriptions, i.Lang)
			if err != nil {
				return err
			}
			i.Description = description
		} else if inventaireEntity.Type == "human" {
			a := InventaireAuthorResult{ID: inventaireEntity.WdId}
			name, err := findLangageField(inventaireEntity.Labels, i.Lang)
			if err != nil {
				return err
			}
			a.Name = name
			desc, err := findLangageField(inventaireEntity.Descriptions, i.Lang)
			if err != nil {
				return err
			}
			a.Description = desc
			i.Author = &a
		}
	}
	return err
}

func findLangageField(multipleMessageFields map[string]json.RawMessage, lang string) (string, error) {
	fieldToParse, ok := multipleMessageFields[lang]
	if ok {
		var parsedField string
		err := json.Unmarshal(fieldToParse, &parsedField)
		if err != nil {
			return "", err
		}
		return parsedField, err
	} else {
		return "", errors.New("multi lang field could not be parsed")
	}
}

func CallInventaireBook(inventaireId string, lang string) (InventaireBookResult, error) {
	queryResult := InventaireBookResult{ID: inventaireId, Lang: lang}
	u, err := computeInventaireApiUrl("entities")
	if err != nil {
		return queryResult, err
	}
	callapiutils.AddQueryParam(u, "action", "by-uris")
	callapiutils.AddQueryParam(u, "relatives", "wdt:P50")
	callapiutils.AddQueryParam(u, "lang", lang)
	callapiutils.AddQueryParam(u, "uris", "wd:"+inventaireId)

	err = callapiutils.FetchAndParseResult(u, &queryResult)
	return queryResult, err
}