package main

import (
	"mime"
	"net/http"
	"strings"
	"time"

	"code.gitea.io/sdk/gitea"
	"github.com/patrickmn/go-cache"
	log "github.com/sirupsen/logrus"
)

var (
	pageCache = cache.New(6 * time.Hour, 1 * time.Hour)
)

type PageContentCache struct {
	Content []byte
	mimeType string
}

func makePageContentCacheEntry(username, path string) string {
	return username + ":" + path
}

func serveFile(username, reponame, path string, giteaClient *gitea.Client, w http.ResponseWriter) {
	// Provide a default
	if path == "" {
		path = "/index.html"
	}

	// Strip away a starting / as it messes with Gitea
	if path[:1] == "/" {
		path = path[1:]
	}

	key := makePageContentCacheEntry(username, path)
	entry, found := pageCache.Get(key)
	var content []byte
	var mimeType string
	var err error
	if found {
		log.Debugf("Returning %s from cache", path)
		content = entry.(PageContentCache).Content
		mimeType = entry.(PageContentCache).mimeType
	} else {
		content, _, err = giteaClient.GetFile(username, reponame, PagesBranch, path, false)
		if err != nil {
			log.Errorf("Failed to get file %s/%s/%s (%s)", username, reponame, path, err)
			w.WriteHeader(404)
			return
		}

		pathParts := strings.Split(path, ".")
		ext := pathParts[len(pathParts) - 1]
		mimeType = mime.TypeByExtension("." + ext)

		pageCache.Set(
			key,
			PageContentCache{
				content,
				mimeType,
			},
			cache.DefaultExpiration,
		)

		log.Debugf("Page %s requested from Gitea and cached in memory", path)
	}

	w.WriteHeader(200)
	w.Header().Set("Content-Type", mimeType)
	w.Write(content)
}