package handlers

import (
	"database/sql"
	"html/template"
	"log"
	"net/http"
	"os"
	"time"

	"github.com/google/uuid"
	"golang.org/x/crypto/bcrypt"
	"paterissa.net/mblog/internal/models"
)

type loginContext struct {
	err *log.Logger
	db  *sql.DB
}

func (ctx *loginContext) index(w http.ResponseWriter, r *http.Request) {
	files := []string{
		"ui/html/base.tmpl.html",
		"ui/html/music_player.tmpl.html",
		"ui/html/pages/login.tmpl.html",
	}

	compiled, err := template.ParseFiles(files...)
	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
		w.Write([]byte("Internal Server Error"))
		ctx.err.Printf("Failed to parse templates: %v\n", err)
		return
	}

	err = compiled.ExecuteTemplate(w, "base", ctx)
	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
		w.Write([]byte("Internal Server Error"))
		ctx.err.Printf("Failed to parse templates: %v\n", err)
		return
	}

	return
}

func (ctx *loginContext) login(w http.ResponseWriter, r *http.Request) {
	if r.Method != "POST" {
		w.WriteHeader(http.StatusMethodNotAllowed)
		w.Write([]byte("Method Not Allowed"))
		return
	}

	err := r.ParseForm()
	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
		w.Write([]byte("Internal Error"))
		ctx.err.Printf("Failed to retrieve form data: %v\n", err)
		return
	}

	user := r.PostForm.Get("user")
	passOne := r.PostForm.Get("pass_one")
	passTwo := r.PostForm.Get("pass_two")

	stmt, err := ctx.db.Prepare("SELECT * FROM logins WHERE name = $1;")
	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
		w.Write([]byte("Internal Error"))
		ctx.err.Printf("Failed to retrieve form data: %v\n", err)
		return
	}
	defer stmt.Close()

	var u models.User

	row := stmt.QueryRow(user)
	err = row.Scan(&u.Id, &u.Name, &u.Time, &u.PassOne, &u.PassTwo)
	if err != nil {
		w.WriteHeader(http.StatusUnauthorized)
		w.Write([]byte("Unauthorized"))
		ctx.err.Printf("Failed to retrieve user info from DB: %v\n", err)
		return
	}

	passOneErr := bcrypt.CompareHashAndPassword([]byte(u.PassOne), []byte(passOne))
	passTwoErr := bcrypt.CompareHashAndPassword([]byte(u.PassTwo), []byte(passTwo))
	if passOneErr != nil || passTwoErr != nil {
		w.WriteHeader(http.StatusUnauthorized)
		w.Write([]byte("Failed to login - not authorized"))
		return
	}

	cookie := http.Cookie{
		Name:     "paterissa_session_token",
		Value:    uuid.New().String(),
		Expires:  time.Now().AddDate(0, 0, 1),
		Path:     "/",
		Domain:   os.Getenv("serv"),
		HttpOnly: true,
		Secure:   true,
	}

	commit, err := ctx.db.Prepare("INSERT INTO cookies (content, user_id, expiration) VALUES ($1, $2, $3);")
	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
		w.Write([]byte("Internal Error"))
		ctx.err.Printf("Failed to prepare DB statement: %v\n", err)
		return
	}

	_, err = commit.Exec(cookie.Value, u.Id, cookie.Expires)
	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
		w.Write([]byte("Internal Error"))
		ctx.err.Printf("Failed to prepare DB statement: %v\n", err)
	}

	http.SetCookie(w, &cookie)
	http.Redirect(w, r, "/", http.StatusFound)
	return
}

func (ctx *loginContext) logout(w http.ResponseWriter, r *http.Request) {
	cookie, err := r.Cookie("paterissa_session_token")
	if err != nil {
		w.WriteHeader(http.StatusUnauthorized)
		w.Write([]byte("Unauthorized"))
		return
	}

	stmt, err := ctx.db.Prepare("UPDATE cookies SET expiration = $1 WHERE content = $2;")
	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
		w.Write([]byte("Internal Error"))
		ctx.err.Printf("Could not prepare DB statement: %v\n", err)
		return
	}
	defer stmt.Close()

	_, err = stmt.Exec(time.Now(), cookie.Value)
	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
		w.Write([]byte("Internal Error"))
		ctx.err.Printf("Could not execute DB statement: %v\n", err)
		return
	}

	cookie = &http.Cookie{
		Name:     "paterissa_session_token",
		Value:    "",
		Path:     "/",
		Domain:   os.Getenv("serv"),
		MaxAge:   -1,
		HttpOnly: true,
	}

	http.SetCookie(w, cookie)
	http.Redirect(w, r, "/", http.StatusFound)
	return
}

func (ctx *loginContext) handle(w http.ResponseWriter, r *http.Request) {
	if r.Method != "POST" {
		ctx.index(w, r)
		return
	} else {
		ctx.login(w, r)
		return
	}
}