package loaders

import (
	"context"
	"git.aiterp.net/stufflog/server/database/repositories"
	"git.aiterp.net/stufflog/server/internal/slerrors"
	"git.aiterp.net/stufflog/server/models"
	"time"
)

// go run github.com/vektah/dataloaden IssueLoader string \*git.aiterp.net/stufflog/server/models.Issue

var issueLoaderCtxKey = "ctx.stufflog.IssueLoader"

func IssueLoaderFromContext(ctx context.Context) *IssueLoader {
	return ctx.Value(issueLoaderCtxKey).(*IssueLoader)
}

func NewIssueLoader(ctx context.Context, issueRepo repositories.IssueRepository) *IssueLoader {
	return &IssueLoader{
		fetch: func(keys []string) ([]*models.Issue, []error) {
			results := make([]*models.Issue, len(keys))
			errors := make([]error, len(keys))

			issues, err := issueRepo.List(ctx, models.IssueFilter{IssueIDs: keys})
			if err != nil {
				for i := range errors {
					errors[i] = err
				}

				return results, errors
			}

			for i, key := range keys {
				found := false
				for _, issue := range issues {
					if issue.ID == key {
						found = true
						results[i] = issue
						break
					}
				}

				if !found {
					errors[i] = slerrors.NotFound("Issue")
				}
			}

			return results, errors
		},
		wait:     time.Millisecond / 2,
		maxBatch: 16,
	}
}