package handlers

import (
	"net/http"
	"strconv"

	"github.com/gin-gonic/gin"
	"github.com/trackeep/backend/config"
	"github.com/trackeep/backend/models"
)

// GetTasks handles GET /api/v1/tasks
func GetTasks(c *gin.Context) {
	db := config.GetDB()
	var tasks []models.Task

	userID := c.GetUint("userID")
	if userID == 0 {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "User not authenticated"})
		return
	}

	if err := db.Where("user_id = ?", userID).Preload("Tags").Find(&tasks).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to fetch tasks"})
		return
	}

	c.JSON(http.StatusOK, tasks)
}

// CreateTask handles POST /api/v1/tasks
func CreateTask(c *gin.Context) {
	db := config.GetDB()
	var task models.Task

	if err := c.ShouldBindJSON(&task); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	userID := c.GetUint("userID")
	if userID == 0 {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "User not authenticated"})
		return
	}
	task.UserID = userID

	if err := db.Create(&task).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to create task"})
		return
	}

	db.Preload("Tags").First(&task, task.ID)

	c.JSON(http.StatusCreated, task)
}

// GetTask handles GET /api/v1/tasks/:id
func GetTask(c *gin.Context) {
	db := config.GetDB()
	id, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid task ID"})
		return
	}

	var task models.Task
	userID := c.GetUint("userID")
	if userID == 0 {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "User not authenticated"})
		return
	}

	if err := db.Where("id = ? AND user_id = ?", id, userID).Preload("Tags").First(&task).Error; err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "Task not found"})
		return
	}

	c.JSON(http.StatusOK, task)
}

// UpdateTask handles PUT /api/v1/tasks/:id
func UpdateTask(c *gin.Context) {
	db := config.GetDB()
	id, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid task ID"})
		return
	}

	var task models.Task
	userID := c.GetUint("userID")
	if userID == 0 {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "User not authenticated"})
		return
	}

	if err := db.Where("id = ? AND user_id = ?", id, userID).First(&task).Error; err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "Task not found"})
		return
	}

	var updateData models.Task
	if err := c.ShouldBindJSON(&updateData); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	if err := db.Model(&task).Updates(updateData).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to update task"})
		return
	}

	db.Preload("Tags").First(&task, task.ID)

	c.JSON(http.StatusOK, task)
}

// DeleteTask handles DELETE /api/v1/tasks/:id
func DeleteTask(c *gin.Context) {
	db := config.GetDB()
	id, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid task ID"})
		return
	}

	var task models.Task
	userID := c.GetUint("userID")
	if userID == 0 {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "User not authenticated"})
		return
	}

	if err := db.Where("id = ? AND user_id = ?", id, userID).First(&task).Error; err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "Task not found"})
		return
	}

	if err := db.Delete(&task).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to delete task"})
		return
	}

	c.JSON(http.StatusOK, gin.H{"message": "Task deleted successfully"})
}