package musicbrainz

import (
	"context"
	"encoding/json"
	"fmt"
	"net/url"
)

// mbArtistSearchResult models the JSON response of the MusicBrainz artist
// search endpoint (/ws/2/artist?query=artist:<name>&fmt=json). Only the
// fields we need for MBID resolution are decoded.
type mbArtistSearchResult struct {
	Artists []struct {
		ID   string `json:"id"`
		Name string `json:"name"`
		Score int   `json:"score"`
	} `json:"artists"`
}

// ResolveArtistMBID resolves a MusicBrainz artist ID (MBID) for the given
// artist name by querying the MusicBrainz artist search endpoint. It returns
// the ID of the first (best-scoring) matching artist. An error is returned if
// the search yields no matches, the response cannot be parsed, or the
// underlying request fails.
func (c *MusicBrainzClient) ResolveArtistMBID(ctx context.Context, name string) (string, error) {
	params := url.Values{}
	params.Set("query", fmt.Sprintf("artist:%s", name))
	params.Set("fmt", "json")
	path := "/artist?" + params.Encode()

	body, err := c.doGet(ctx, path)
	if err != nil {
		return "", fmt.Errorf("resolve MBID for artist %q: %w", name, err)
	}

	var result mbArtistSearchResult
	if err := json.Unmarshal(body, &result); err != nil {
		return "", fmt.Errorf("parse artist search response for %q: %w", name, err)
	}

	if len(result.Artists) == 0 {
		return "", fmt.Errorf("no MusicBrainz artist found for %q", name)
	}

	return result.Artists[0].ID, nil
}