package ttbp

import (
	"bufio"
	"encoding/json"
	"os"
	"path"
	"sort"
	"time"

	"git.tilde.town/nbsp/neofeels/config"
)

var (
	PathVar      = "/var/global/ttbp"
	PathVarWWW   = path.Join(PathVar, "www")
	PathLive     = "https://tilde.town/~"
	PathUserFile = path.Join(PathVar, "users.txt")
	PathGraff    = path.Join(PathVar, "graffiti")
	PathWall     = path.Join(PathGraff, "wall.txt")
	PathWallLock = path.Join(PathGraff, ".lock")
)

type User struct {
	Name          string
	Publishing    bool
	PublishDir    string
	LastPublished time.Time
}

// GetUsers gets all users with a valid ttbp config, with their name, publishing
// settings, and date of last publish, if any.
func GetUsers() (users []User) {
	userDirs, _ := os.ReadDir("/home")
	for _, user := range userDirs {
		if !user.IsDir() {
			continue
		}
		if file, err := os.Open(path.Join("/home", user.Name(), ".ttbp/config/ttbprc")); err == nil {
			defer file.Close()

			// get user config
			var config config.Config
			decoder := json.NewDecoder(file)
			err = decoder.Decode(&config)
			if err != nil {
				continue
			}

			// get last published file
			entries, err := os.ReadDir(path.Join("/home", user.Name(), ".ttbp/entries"))
			if err != nil {
				continue
			}
			var lastPublished time.Time = *new(time.Time)
			if len(entries) > 0 {
				info, err := entries[len(entries)-1].Info()
				if err != nil {
					continue
				}
				lastPublished = info.ModTime()
			}

			users = append(users, User{
				Name:          user.Name(),
				Publishing:    config.Publishing,
				PublishDir:    config.PublishDir,
				LastPublished: lastPublished,
			})
		}
	}
	return users
}

// SortUsersByRecent sorts users, putting the users with the most recent
// published feels at the beginning.
func SortUsersByRecent(users []User) []User {
	sort.Slice(users, func(i, j int) bool {
		return users[i].LastPublished.After(users[j].LastPublished)
	})
	return users
}

type Post struct {
	Date       time.Time
	LastEdited time.Time
	Words      int
	Author     string
}

func GetPostsForUser(user string) (posts []Post) {
	postFiles, err := os.ReadDir(path.Join("/home", user, ".ttbp/entries"))
	if err != nil {
		return
	}
	for _, post := range postFiles {
		// retrieve date of file
		// assume file ends in .txt
		fileDate, err := time.Parse("20060102.txt", post.Name())
		if err != nil {
			continue
		}

		if file, err := os.Open(path.Join("/home", user, ".ttbp/entries", post.Name())); err == nil {
			defer file.Close()

			// get number of words in file
			scanner := bufio.NewScanner(file)
			scanner.Split(bufio.ScanWords)
			count := 0
			for scanner.Scan() {
				count++
			}

			// get modtime of file
			stat, err := file.Stat()
			if err != nil {
				continue
			}

			posts = append([]Post{Post{
				Author:     user,
				Date:       fileDate,
				LastEdited: stat.ModTime(),
				Words:      count,
			}}, posts...)
		}
	}
	return
}

// SortUsersByRecent sorts posts, putting the posts that were most recently
// edited first in the list.
func SortPostsByRecent(posts []Post) []Post {
	sort.Slice(posts, func(i, j int) bool {
		return posts[i].LastEdited.After(posts[j].LastEdited)
	})
	return posts
}