package main

import (
	crand "crypto/rand"
	"encoding/hex"
	"html/template"
	"net/http"
	"time"
)

func Must[T any](value T, err error) T {
	if err != nil {
		panic(err)
	}
	return value
}

func generateRandomID(length int) (string, error) {
	data := make([]byte, 32)
	if _, err := crand.Read(data); err != nil {
		return "", err
	}
	return hex.EncodeToString(data), nil
}

func GetSession(w http.ResponseWriter, r *http.Request) (*Session, error) {
	cookie, err := r.Cookie("session")
	if err != nil {
		return makeNewSession(w)
	}

	session := GetSessionByID(cookie.Value)
	if session == nil {
		return makeNewSession(w)
	}

	// update cookie expiration date
	session.ExpirationDate = time.Now().AddDate(1, 0, 0)
	if err := UpdateSession(session); err != nil {
		return nil, err
	}
	http.SetCookie(w, &http.Cookie{
		Name:     "session",
		Value:    session.ID,
		Expires:  session.ExpirationDate,
		Secure:   true,
		HttpOnly: true,
	})

	return session, nil
}

func makeNewSession(w http.ResponseWriter) (*Session, error) {
	session, err := NewSession()
	if err != nil {
		return nil, err
	}

	if err := InsertSession(session); err != nil {
		return nil, err
	}

	// insert default bookmarks
	for _, bookmark := range DefaultBookmarks() {
		bookmark.SessionID = session.ID
		if err := InsertBookmark(&bookmark); err != nil {
			return nil, err
		}
	}

	// insert default settings
	settings := DefaultSettings()
	settings.SessionID = session.ID
	if err := InsertSettings(settings); err != nil {
		return nil, err
	}

	http.SetCookie(w, &http.Cookie{
		Name:     "session",
		Value:    session.ID,
		Expires:  session.ExpirationDate,
		Secure:   true,
		HttpOnly: true,
	})

	return session, nil
}

var tmplFuncs = template.FuncMap{
	"js": func(s string) template.JS {
		return template.JS(s)
	},
	"jss": func(s string) template.JSStr {
		return template.JSStr(s)
	},
	"css": func(s string) template.CSS {
		return template.CSS(s)
	},
	"attr": func(s string) template.HTMLAttr {
		return template.HTMLAttr(s)
	},
	"safe": func(s string) template.HTML {
		return template.HTML(s)
	},
	"url": func(s string) template.URL {
		return template.URL(s)
	},
}