package upstream

import (
	"fmt"
	"net/url"
	"path"
	"strings"

	"github.com/valyala/fasthttp"

	"codeberg.org/codeberg/pages/server/cache"
)

// CheckCanonicalDomain returns the canonical domain specified in the repo (using the `.domains` file).
func CheckCanonicalDomain(targetOwner, targetRepo, targetBranch, actualDomain, mainDomainSuffix, giteaRoot, giteaAPIToken string, canonicalDomainCache cache.SetGetKey) (string, bool) {
	return checkCanonicalDomain(targetOwner, targetRepo, targetBranch, actualDomain, mainDomainSuffix, giteaRoot, giteaAPIToken, canonicalDomainCache)
}

func giteaRawContent(targetOwner, targetRepo, ref, giteaRoot, giteaAPIToken, resource string) ([]byte, error) {
	req := fasthttp.AcquireRequest()

	req.SetRequestURI(path.Join(giteaRoot, giteaApiRepos, targetOwner, "/", targetRepo, "/raw/", resource, "?ref="+url.QueryEscape(ref)))
	req.Header.Set(fasthttp.HeaderAuthorization, giteaAPIToken)
	res := fasthttp.AcquireResponse()

	if err := client.Do(req, res); err != nil {
		return nil, err
	}
	if res.StatusCode() != fasthttp.StatusOK {
		return nil, fmt.Errorf("unexpected status code '%d'", res.StatusCode())
	}
	return res.Body(), nil
}

func checkCanonicalDomain(targetOwner, targetRepo, targetBranch, actualDomain, mainDomainSuffix, giteaRoot, giteaAPIToken string, canonicalDomainCache cache.SetGetKey) (string, bool) {
	var (
		domains []string
		valid   bool
	)
	if cachedValue, ok := canonicalDomainCache.Get(targetOwner + "/" + targetRepo + "/" + targetBranch); ok {
		domains = cachedValue.([]string)
		for _, domain := range domains {
			if domain == actualDomain {
				valid = true
				break
			}
		}
	} else {

		body, err := giteaRawContent(giteaRoot, targetRepo, targetBranch, giteaRoot, giteaAPIToken, canonicalDomainConfig)
		if err == nil {
			for _, domain := range strings.Split(string(body), "\n") {
				domain = strings.ToLower(domain)
				domain = strings.TrimSpace(domain)
				domain = strings.TrimPrefix(domain, "http://")
				domain = strings.TrimPrefix(domain, "https://")
				if len(domain) > 0 && !strings.HasPrefix(domain, "#") && !strings.ContainsAny(domain, "\t /") && strings.ContainsRune(domain, '.') {
					domains = append(domains, domain)
				}
				if domain == actualDomain {
					valid = true
				}
			}
		}
		domains = append(domains, targetOwner+mainDomainSuffix)
		if domains[len(domains)-1] == actualDomain {
			valid = true
		}
		if targetRepo != "" && targetRepo != "pages" {
			domains[len(domains)-1] += "/" + targetRepo
		}
		_ = canonicalDomainCache.Set(targetOwner+"/"+targetRepo+"/"+targetBranch, domains, canonicalDomainCacheTimeout)
	}
	return domains[0], valid
}