package db

import (
	"context"
	"fmt"
	"net/http"
	"strings"

	"github.com/H1K0/Kiraku/internal/models"
	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgconn"
)

func CreditsGetByPerson(ctx context.Context, user_id, person_id, sort string) (credits []models.PersonCredit, statusCode int, err error) {
	ok, _ := UserAuth(ctx, user_id)
	if !ok {
		err = fmt.Errorf("unauthorized")
		statusCode = http.StatusUnauthorized
		return
	}
	query := "SELECT t.id AS track_id, t.name AS track_name, t.duration AS track_duration, COALESCE(t.release_date::text, '') AS track_releaseDate, t.acquire_datetime AS track_acquireDatetime, r.id AS role_id, r.name AS role_name, COALESCE(c.alias, '') AS alias " +
		"FROM credits c " +
		"JOIN tracks t ON t.id=c.track_id " +
		"JOIN roles r ON r.id=c.role_id " +
		"WHERE c.person_id=$1"
	if sort != "" {
		sort_options := strings.Split(sort, ",")
		query += " ORDER BY "
		for i, sort_option := range sort_options {
			sort_order := sort_option[:1]
			sort_field := sort_option[1:]
			switch sort_order {
			case "+":
				sort_order = "ASC"
			case "-":
				sort_order = "DESC"
			default:
				err = fmt.Errorf("invalid sorting order mark: %q", sort)
				statusCode = http.StatusBadRequest
				return
			}
			switch sort_field {
			case "track.name":
				fallthrough
			case "track.releaseDate":
				fallthrough
			case "track.acquireDatetime":
				fallthrough
			case "track.duration":
				fallthrough
			case "role.name":
				sort_field = strings.ReplaceAll(sort_field, ".", "_")
			case "track.sortName":
				sort_field = "COALESCE(t.sort_name, t.name)"
			case "alias":
			default:
				err = fmt.Errorf("invalid sorting field: %q", sort_field)
				statusCode = http.StatusBadRequest
				return
			}
			if i > 0 {
				query += ", "
			}
			query += fmt.Sprintf("%s %s NULLS LAST", sort_field, sort_order)
		}
	}
	row := connPool.QueryRow(ctx, "SELECT 1 FROM persons WHERE id=$1", person_id)
	err = row.Scan(nil)
	if err != nil {
		if err == pgx.ErrNoRows {
			err = fmt.Errorf("not found")
			statusCode = http.StatusNotFound
			return
		}
		pgErr := err.(*pgconn.PgError)
		if pgErr.Code == "22P02" {
			err = fmt.Errorf("%s", pgErr.Message)
			statusCode = http.StatusBadRequest
		} else {
			statusCode = http.StatusInternalServerError
		}
		return
	}
	rows, err := connPool.Query(ctx, query, person_id)
	if err != nil {
		statusCode = http.StatusInternalServerError
		return
	}
	count := 0
	for rows.Next() {
		var credit models.PersonCredit
		err = rows.Scan(
			&credit.Track.ID, &credit.Track.Name, &credit.Track.Duration, &credit.Track.ReleaseDate, &credit.Track.AcquireDatetime,
			&credit.Role.ID, &credit.Role.Name, &credit.Alias,
		)
		if err != nil {
			statusCode = http.StatusInternalServerError
			return
		}
		credits = append(credits, credit)
		count++
	}
	err = rows.Err()
	if err != nil {
		statusCode = http.StatusInternalServerError
		return
	}
	statusCode = http.StatusOK
	return
}

func CreditsGetByTrack(ctx context.Context, user_id, track_id, sort string) (credits []models.TrackCredit, statusCode int, err error) {
	ok, _ := UserAuth(ctx, user_id)
	if !ok {
		err = fmt.Errorf("unauthorized")
		statusCode = http.StatusUnauthorized
		return
	}
	query := "SELECT p.id AS person_id, p.name AS person_name, COALESCE(p.sort_name, '') AS person_sortName, r.id AS role_id, r.name AS role_name, COALESCE(c.alias, '') AS alias " +
		"FROM credits c " +
		"JOIN persons p ON p.id=c.person_id " +
		"JOIN roles r ON r.id=c.role_id " +
		"WHERE c.track_id=$1"
	if sort != "" {
		sort_options := strings.Split(sort, ",")
		query += " ORDER BY "
		for i, sort_option := range sort_options {
			sort_order := sort_option[:1]
			sort_field := sort_option[1:]
			switch sort_order {
			case "+":
				sort_order = "ASC"
			case "-":
				sort_order = "DESC"
			default:
				err = fmt.Errorf("invalid sorting order mark: %q", sort)
				statusCode = http.StatusBadRequest
				return
			}
			switch sort_field {
			case "person.name":
				fallthrough
			case "role.name":
				sort_field = strings.ReplaceAll(sort_field, ".", "_")
			case "person.sortName":
				sort_field = "COALESCE(p.sort_name, p.name)"
			case "alias":
			default:
				err = fmt.Errorf("invalid sorting field: %q", sort_field)
				statusCode = http.StatusBadRequest
				return
			}
			if i > 0 {
				query += ", "
			}
			query += fmt.Sprintf("%s %s NULLS LAST", sort_field, sort_order)
		}
	}
	row := connPool.QueryRow(ctx, "SELECT 1 FROM tracks WHERE id=$1", track_id)
	err = row.Scan(nil)
	if err != nil {
		if err == pgx.ErrNoRows {
			err = fmt.Errorf("not found")
			statusCode = http.StatusNotFound
			return
		}
		pgErr := err.(*pgconn.PgError)
		if pgErr.Code == "22P02" {
			err = fmt.Errorf("%s", pgErr.Message)
			statusCode = http.StatusBadRequest
		} else {
			statusCode = http.StatusInternalServerError
		}
		return
	}
	rows, err := connPool.Query(ctx, query, track_id)
	if err != nil {
		statusCode = http.StatusInternalServerError
		return
	}
	count := 0
	for rows.Next() {
		var credit models.TrackCredit
		err = rows.Scan(
			&credit.Person.ID, &credit.Person.Name, &credit.Person.SortName,
			&credit.Role.ID, &credit.Role.Name, &credit.Alias,
		)
		if err != nil {
			statusCode = http.StatusInternalServerError
			return
		}
		credits = append(credits, credit)
		count++
	}
	err = rows.Err()
	if err != nil {
		statusCode = http.StatusInternalServerError
		return
	}
	statusCode = http.StatusOK
	return
}