package pages

import (
	"os"
	"os/exec"
	"regexp"
	"runtime"
	"sort"
	"strconv"
	"strings"

	log "log/slog"

	"github.com/ProjectSegfault/publapi/utils"
	"github.com/gofiber/fiber/v2"
	"github.com/spf13/viper"
)

type UserStruct struct {
	Status int        `json:"status"`
	Online int        `json:"online"`
	Total  int        `json:"total"`
	Users  []UserInfo `json:"users"`
}

type UserInfo struct {
	Name      string `json:"name"`
	FullName  string `json:"fullName"`
	Desc      string `json:"desc"`
	Online    bool   `json:"online"`
	Op        bool   `json:"op"`
	Created   int    `json:"created"`
	Email     string `json:"email"`
	Matrix    string `json:"matrix"`
	Fediverse string `json:"fediverse"`
	Website   string `json:"website"`
	Capsule   string `json:"capsule"`
	Loc       string `json:"loc"`
}

type ByAdminAndName []UserInfo

func (a ByAdminAndName) Len() int { return len(a) }
func (a ByAdminAndName) Less(i, j int) bool {
	// If one person is an admin and the other is not, place the admin first
	if a[i].Op && !a[j].Op {
		return true
	} else if !a[i].Op && a[j].Op {
		return false
	}

	// If both persons are admins or both are not, sort by name
	return a[i].Name < a[j].Name
}
func (a ByAdminAndName) Swap(i, j int) { a[i], a[j] = a[j], a[i] }

func UserError(message string, username string, err error) {
	log.Error("message", message, log.Any("err", err), "username", username)
}

func userData(username, usersonline, ops string) UserInfo {
	regex := "(^| )" + username + "($| )"
	isonline, err := regexp.MatchString(string(regex), string(usersonline))
	if err != nil {
		UserError("couldn't get online status for user", username, err)
	}
	isop, operr := regexp.MatchString(string(regex), string(ops))
	if operr != nil {
		UserError("couldn't get op status for user", username, operr)
	}
	cmd := "/usr/bin/stat -c %W /home/" + username
	crd, crerr := exec.Command("bash", "-c", cmd).Output()
	if crerr != nil {
		UserError("couldn't stat user", username, crerr)
	}
	crdstr := strings.TrimSuffix(string(crd), "\n")
	filename := "/home/" + username + "/meta-info.toml"
	filestat, error := os.Stat(filename)
	if error != nil {
		if os.IsNotExist(error) {
			UserError("user doesn't have a meta-info.toml", username, error)
			var user UserInfo
			user.Name = username
			user.Created, _ = strconv.Atoi(crdstr)
			if isonline {
				user.Online = true
			} else {
				user.Online = false
			}
			if isop {
				user.Op = true
			} else {
				user.Op = false
			}
			return user
		}
	}
	// Check file size of meta-info.toml. If it's over 100 kB, bail
	if filestat.Size() > 100_000 {
		log.Error("user's meta-info.toml is above the 100 kB file size limit", "user", username)
		user := UserInfo{
			Name:   username,
			Online: false,
			Op:     false,
		}
		user.Created, _ = strconv.Atoi(crdstr)
		if isonline {
			user.Online = true
		}
		if isop {
			user.Op = true
		}
		return user
	}
	viper.SetConfigFile(filename)
	if err := viper.ReadInConfig(); err != nil {
		log.Error("message", "couldn't read a users meta-info.toml file.", "error", log.Any("err", err), "user", username)
		user := UserInfo{
			Name: username,
		}
		user.Created, _ = strconv.Atoi(crdstr)
		if isonline {
			user.Online = true
		} else {
			user.Online = false
		}
		if isop {
			user.Op = true
		} else {
			user.Op = false
		}
		return user
	}
	user := UserInfo{
		Name:      username,
		FullName:  viper.GetString("fullname"),
		Capsule:   viper.GetString("gemini"),
		Website:   viper.GetString("website"),
		Desc:      viper.GetString("description"),
		Email:     viper.GetString("email"),
		Matrix:    viper.GetString("matrix"),
		Fediverse: viper.GetString("fediverse"),
		Loc:       viper.GetString("location"),
		Op:        false,
		Online:    false,
	}
	user.Created, _ = strconv.Atoi(crdstr)
	if isop {
		user.Op = true
	}
	if isonline {
		user.Online = true
	}
	return user
}

func UsersPage(c *fiber.Ctx) error {
	if runtime.GOOS == "windows" {
		return c.JSON(fiber.Map{
			"message": "/users is not supported on Windows",
			"status":  c.Response().StatusCode(),
		})
	}
	// Get the number of users online
	usersOnline, err := exec.Command("bash", "-c", "/usr/bin/users").Output()
	if err != nil {
		log.Error("error", log.Any("error", err))
		return c.SendStatus(fiber.StatusInternalServerError)
	}
	usersOnlineStr := string(usersOnline)
	usersOnlineDedup := utils.Dedup(usersOnlineStr)
	var output int
	if strings.Contains(usersOnlineDedup, " ") {
		outputa := int(strings.Count(usersOnlineDedup, " "))
		output = outputa + 1
	} else if usersOnlineDedup == "" {
		output = 0
	} else {
		output = 1
	}
	// Get OPs
	ops, opserr := exec.Command("bash", "-c", "/usr/bin/members sudo").Output()
	if opserr != nil {
		log.Error("couldn't get ops", "error", log.Any("err", opserr))
		return c.SendStatus(fiber.StatusInternalServerError)
	}
	opstr := string(ops)
	// Get all users
	users, err2 := exec.Command("bash", "-c", "/usr/bin/ls /home").Output()
	if err2 != nil {
		log.Error("couldn't get all users", "error", log.Any("err", err2))
		return c.SendStatus(fiber.StatusInternalServerError)
	}
	userstr := strings.TrimSuffix(string(users), "\n")
	usersarr := strings.Split(userstr, "\n")
	// Fill user info
	var userInfoArray []UserInfo
	for i := 0; i < len(usersarr); i++ {
		uname := string(usersarr[i])
		userInfoArray = append(
			userInfoArray,
			userData(
				uname,
				strings.TrimSuffix(usersOnlineDedup, "\n"),
				strings.TrimSuffix(opstr, "\n"),
			),
		)
	}
	sort.Sort(ByAdminAndName(userInfoArray))
	data := UserStruct{
		Status: c.Response().StatusCode(),
		Online: output,
		Users:  userInfoArray,
		Total:  int(strings.Count(userstr, "\n")),
	}
	return c.JSON(data)
}