package skate

import (
	"fmt"
	"strconv"
	"strings"
)

// RefToRelease converts a ref to a release. Set a extra.skate.status flag to
// be able to distinguish converted entities later.
func RefToRelease(ref *Ref) (*Release, error) {
	var (
		release  Release
		b        = ref.Biblio
		contribs = make([]struct {
			Index   int    `json:"index,omitempty"`
			RawName string `json:"raw_name,omitempty"`
			Role    string `json:"role,omitempty"`
		}, len(b.ContribRawNames))
	)
	release.Ident = ref.ReleaseIdent
	release.WorkID = ref.WorkIdent
	release.ExtIDs.Arxiv = b.ArxivId
	release.ExtIDs.DOI = b.DOI
	release.ExtIDs.PMID = b.PMID
	release.ExtIDs.PMCID = b.PMCID
	release.Title = b.Title
	release.Publisher = b.Publisher
	release.ContainerName = b.ContainerName
	release.Volume = b.Volume
	release.Issue = b.Issue
	release.Pages = b.Pages
	if ref.ReleaseYear > 1000 {
		release.ReleaseYearValue = fmt.Sprintf("%d", ref.ReleaseYear)
	}
	for i, name := range b.ContribRawNames {
		contribs[i].Index = i
		contribs[i].RawName = name
	}
	release.Contribs = contribs
	return &release, nil
}

// Ref is a reference document, can be very partial.
type Ref struct {
	Biblio struct {
		ArxivId         string   `json:"arxiv_id,omitempty"`
		ContainerName   string   `json:"container_name,omitempty"`
		ContribRawNames []string `json:"contrib_raw_names,omitempty"`
		DOI             string   `json:"doi,omitempty"`
		Issue           string   `json:"issue,omitempty"`
		PMCID           string   `json:"pmcid,omitempty"`
		PMID            string   `json:"pmid,omitempty"`
		Pages           string   `json:"pages,omitempty"`
		Publisher       string   `json:"publisher,omitempty"`
		Title           string   `json:"title,omitempty"`
		Unstructured    string   `json:"unstructured,omitempty"`
		Url             string   `json:"url,omitempty"`
		Volume          string   `json:"volume,omitempty"`
		Year            int64    `json:"year,omitempty"`
	} `json:"biblio"`
	Index        int64  `json:"index,omitempty"`
	Key          string `json:"key,omitempty"`
	RefSource    string `json:"ref_source,omitempty"`
	ReleaseYear  int    `json:"release_year,omitempty"`
	ReleaseIdent string `json:"release_ident,omitempty"`
	ReleaseStage string `json:"release_stage,omitempty"`
	WorkIdent    string `json:"work_ident,omitempty"`
}

// Release document. Note that we may have varying types for some fields.
// Mitigation for now is to make the field an interface{}, name the field
// "...Value" and to add a method with the field name, doing type assertion.
// Example: ReleaseYearValue interface{}, ReleaseYear() int, etc.
type Release struct {
	ContainerID   string `json:"container_id,omitempty"`
	ContainerName string `json:"container_name,omitempty"`
	Contribs      []struct {
		Index   int    `json:"index,omitempty"`
		RawName string `json:"raw_name,omitempty"`
		Role    string `json:"role,omitempty"`
	} `json:"contribs,omitempty"`
	ExtIDs struct {
		DOI         string `json:"doi,omitempty"`
		PMID        string `json:"pmid,omitempty"`
		PMCID       string `json:"pmcid,omitempty"`
		Arxiv       string `json:"arxiv,omitempty"`
		Core        string `json:"core,omitempty"`
		WikidataQID string `json:"wikidata_qid,omitempty"`
		Jstor       string `json:"jstor,omitempty"`
	} `json:"ext_ids,omitempty"`
	Ident     string `json:"ident,omitempty"`
	Publisher string `json:"publisher,omitempty"`
	Refs      []struct {
		ContainerName string `json:"container_name,omitempty"`
		Extra         struct {
			DOI     string   `json:"doi,omitempty"`
			Authors []string `json:"authors,omitempty"`
			Key     string   `json:"key,omitempty"`
			Year    string   `json:"year,omitempty"`
			Locator string   `json:"locator,omitempty"`
			Volume  string   `json:"volume,omitempty"`
		} `json:"extra"`
		Index   int64  `json:"index,omitempty"`
		Key     string `json:"key,omitempty"`
		Locator string `json:"locator,omitempty"`
		Year    int64  `json:"year,omitempty"`
	} `json:"refs,omitempty"`
	ReleaseDate      string      `json:"release_date,omitempty"`
	ReleaseYearValue interface{} `json:"release_year,omitempty"` // might be int or str
	ReleaseStage     string      `json:"release_stage,omitempty"`
	ReleaseType      string      `json:"release_type,omitempty"`
	Issue            string      `json:"issue,omitempty"`
	Volume           string      `json:"volume,omitempty"`
	Pages            string      `json:"pages,omitempty"`
	Title            string      `json:"title,omitempty"`
	WorkID           string      `json:"work_id,omitempty"`
	Extra            struct {
		ContainerName string      `json:"container_name,omitempty"`
		SubtitleValue interface{} `json:"subtitle,omitempty"` // []str or str
		Crossref      struct {
			Type string `json:"type,omitempty"`
		} `json:"crossref,omitempty"`
		DataCite struct {
			MetadataVersion int                `json:"metadataVersion,omitempty"`
			Relations       []DataCiteRelation `json:"relations,omitempty"`
		} `json:"datacite,omitempty"`
		Skate struct {
			// Mark as converted (e.g. by setting status to "ref")
			Status string `json:"status,omitempty"`
			// Carry the ref index and key around.
			Ref struct {
				Index   int64  `json:"index,omitempty"`
				Key     string `json:"key,omitempty"`
				Locator string `json:"locator,omitempty"`
			} `json:"ref,omitempty"`
			ResearchGate struct {
				URL string `json:"url,omitempty"`
			} `json:"rg,omitempty"`
		} `json:"skate,omitempty"`
	} `json:"extra,omitempty"`
}

// Subtitle returns a slice of subtitle strings.
func (r *Release) Subtitle() (result []string) {
	switch v := r.Extra.SubtitleValue.(type) {
	case []interface{}:
		for _, e := range v {
			result = append(result, fmt.Sprintf("%v", e))
		}
		return result
	case []string:
		return v
	case string:
		return []string{v}
	}
	return []string{}
}

// ReleaseYearString returns release year as string.
func (r *Release) ReleaseYearString() string {
	return fmt.Sprintf("%d", r.ReleaseYear())
}

// ReleaseYear returns year as int, no further validity checks.
func (r *Release) ReleaseYear() int {
	switch v := r.ReleaseYearValue.(type) {
	case int:
		return v
	case float64:
		return int(v)
	case string:
		w, err := strconv.Atoi(v)
		if err != nil {
			return 0
		}
		return w
	default:
		return 0
	}
}

// DataCiteRelation as it appears in the release extra field.
type DataCiteRelation struct {
	RelatedIdentifierType  string      `json:"relatedIdentifierType,omitempty"`
	RelatedIdentifierValue interface{} `json:"relatedIdentifier,omitempty"`
}

// RelatedIdentifier returns the identifier as string.
func (r *DataCiteRelation) RelatedIdentifier() string {
	switch v := r.RelatedIdentifierValue.(type) {
	case string:
		return v
	default:
		return fmt.Sprintf("%v", v)
	}
}

// Sitemap basic JSON style, e.g. for https://archive.org/details/rg_sitemap_2021_02_23.
type Sitemap struct {
	Lastmod string `json:"lastmod,omitempty"`
	Title   string `json:"title,omitempty"`
	URL     string `json:"url,omitempty"`
}

// BiblioRef as a prototype for indexing, https://is.gd/yicTom.
type BiblioRef struct {
	Key                    string `json:"_id,omitempty"`
	IndexedTs              int64  `json:"indexed_ts,omitempty"` // XXX: maybe: epoch_millis, https://www.elastic.co/guide/en/elasticsearch/reference/current/date.html
	SourceReleaseIdent     string `json:"source_release_ident,omitempty"`
	SourceWorkIdent        string `json:"source_work_ident,omitempty"`
	SourceWikipediaArticle string `json:"source_wikipedia_article,omitempty"`
	SourceReleaseStage     string `json:"source_release_stage,omitempty"`
	SourceYear             string `json:"source_year,omitempty"`
	RefIndex               int64  `json:"ref_index,omitempty"` // 1-based
	RefKey                 string `json:"ref_key,omitempty"`
	RefLocator             string `json:"ref_locator,omitempty"`
	TargetReleaseIdent     string `json:"target_release_ident,omitempty"`
	TargetWorkIdent        string `json:"target_work_ident,omitempty"`
	TargetOpenLibraryWork  string `json:"target_openlibrary_work,omitempty"`
	TargetURLSurt          string `json:"target_url_surt,omitempty"`
	TargetURL              string `json:"target_url,omitempty"`
	MatchProvenance        string `json:"match_provenance,omitempty"`
	MatchStatus            string `json:"match_status,omitempty"`
	MatchReason            string `json:"match_reason,omitempty"`
	TargetUnstructured     string `json:"target_unstructured,omitempty"`
	TargetCSL              string `json:"target_csl,omitempty"`
}

// ReleaseCluster, a list of match candidates. This is typically serialized as a
// single JSON line.
type ReleaseCluster struct {
	Key    string     `json:"k"`
	Values []*Release `json:"v"`
}

// OneNonRef returns the first non-reference release found in a cluster, or an
// error, if none has been found. This depends on converted references using
// the status "ref" in extra. We use this in mixed clusters (catalog entries
// and references converted into releases).
func (rc *ReleaseCluster) OneNonRef() (*Release, error) {
	for _, re := range rc.Values {
		if re.Extra.Skate.Status != "ref" {
			return re, nil
		}
	}
	return nil, fmt.Errorf("no reference/release found for cluster key: %v", rc.Key)
}

// MinimalCitations variant from archive.org/details/wikipedia_citations_2020-07-14.
type MinimalCitations struct {
	IDList         string `json:"ID_list"`
	PageTitle      string `json:"page_title"`
	Title          string `json:"Title"`
	TypeOfCitation string `json:"type_of_citation"`
}

// IDList with commonly used identifier from wikipedia citations.
type IDList struct {
	ISBN  string `json:"isbn,omitempty"`
	DOI   string `json:"doi,omitempty"`
	PMID  string `json:"pmid,omitempty"`
	ISSN  string `json:"issn,omitempty"`
	JSTOR string `json:"jstor,omitempty"`
	PMC   string `json:"pmc,omitempty"`
	ARXIV string `json:"arxiv,omitempty"`
	OL    string `json:"ol,omitempty"`
}

// IsZero returns true, if none of the identifiers is defined.
func (l *IDList) IsZero() bool {
	return *l == IDList{}
}

// ParseIDList parses out the identifiers from a citation document, the IDList
// values look something like this: "{BIBCODE=1992ApJ...399L..31C,
// DOI=10.1086/186599}".
func (c *MinimalCitations) ParseIDList() (result IDList) {
	if len(c.IDList) < 3 {
		return result
	}
	var (
		s     = c.IDList[1 : len(c.IDList)-1] // get rid of "{" and "}"
		parts = strings.Split(s, ",")
		pair  []string
	)
	for _, part := range parts {
		pair = strings.Split(part, "=")
		if len(pair) != 2 {
			continue
		}
		pair[0] = strings.TrimSpace(pair[0])
		pair[1] = strings.TrimSpace(pair[1])
		switch pair[0] {
		case "ISBN":
			result.ISBN = pair[1]
		case "DOI":
			result.DOI = pair[1]
		case "PMID":
			result.PMID = pair[1]
		case "ISSN":
			result.ISSN = pair[1]
		case "PMC":
			result.PMC = pair[1]
		case "JSTOR":
			result.JSTOR = pair[1]
		case "ARXIV":
			result.ARXIV = pair[1]
		case "OL":
			result.OL = pair[1]
		default:
			continue
		}
	}
	return result
}