package handlers

import (
    "log"
    "net/http"
    "strconv"
    "threadr/models"
    "github.com/gorilla/sessions"
)

func LikeHandler(app *App) http.HandlerFunc {
    return func(w http.ResponseWriter, r *http.Request) {
        if r.Method != http.MethodPost {
            http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
            return
        }

        session := r.Context().Value("session").(*sessions.Session)
        userID, ok := session.Values["user_id"].(int)
        if !ok {
            http.Error(w, "Unauthorized", http.StatusUnauthorized)
            return
        }

        postIDStr := r.FormValue("post_id")
        postID, err := strconv.Atoi(postIDStr)
        if err != nil {
            http.Error(w, "Invalid post ID", http.StatusBadRequest)
            return
        }

        likeType := r.FormValue("type")
        if likeType != "like" && likeType != "dislike" {
            http.Error(w, "Invalid like type", http.StatusBadRequest)
            return
        }

        existingLike, err := models.GetLikeByPostAndUser(app.DB, postID, userID)
        if err != nil {
            log.Printf("Error checking existing like: %v", err)
            http.Error(w, "Internal Server Error", http.StatusInternalServerError)
            return
        }

        if existingLike != nil {
            if existingLike.Type == likeType {
                err = models.DeleteLike(app.DB, postID, userID)
                if err != nil {
                    log.Printf("Error deleting like: %v", err)
                    http.Error(w, "Internal Server Error", http.StatusInternalServerError)
                    return
                }
            } else {
                err = models.UpdateLikeType(app.DB, postID, userID, likeType)
                if err != nil {
                    log.Printf("Error updating like: %v", err)
                    http.Error(w, "Internal Server Error", http.StatusInternalServerError)
                    return
                }
            }
        } else {
            like := models.Like{
                PostID: postID,
                UserID: userID,
                Type:   likeType,
            }
            err = models.CreateLike(app.DB, like)
            if err != nil {
                log.Printf("Error creating like: %v", err)
                http.Error(w, "Internal Server Error", http.StatusInternalServerError)
                return
            }
        }

        w.WriteHeader(http.StatusOK)
        w.Write([]byte("OK"))
    }
}