package handlers

import (
	"net/http"

	"github.com/celestia-trace/backend/models"
	"github.com/gin-gonic/gin"
	"gorm.io/gorm"
)

type DeviceHandler struct {
	DB *gorm.DB
}

// GetDevices returns all bound devices for the authenticated user
func (h *DeviceHandler) GetDevices(c *gin.Context) {
	userID := c.GetString("userID")
	var devices []models.BoundDevice
	if err := h.DB.Where("user_id = ?", userID).Order("bound_at desc").Find(&devices).Error; err != nil {
		respondError(c, http.StatusInternalServerError, 500, "failed to query devices")
		return
	}
	respondSuccess(c, devices)
}

// BindDevice binds a new Spark device to the authenticated user
func (h *DeviceHandler) BindDevice(c *gin.Context) {
	userID := c.GetString("userID")
	var req models.BindDeviceRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		respondError(c, http.StatusBadRequest, 400, "invalid device parameters")
		return
	}

	var device models.BoundDevice
	err := h.DB.Where("user_id = ? AND peripheral_uuid = ?", userID, req.PeripheralUUID).First(&device).Error
	if err != nil && err != gorm.ErrRecordNotFound {
		respondError(c, http.StatusInternalServerError, 500, "failed to query device")
		return
	}
	device.UserID = userID
	device.Name = req.Name
	device.PeripheralUUID = req.PeripheralUUID
	device.HardwareMAC = req.HardwareMAC
	device.FirmwareVersion = req.FirmwareVersion
	if req.BatteryLevel != nil {
		device.BatteryLevel = *req.BatteryLevel
	}
	if req.FreeStorageMB != nil {
		device.FreeStorageMB = *req.FreeStorageMB
	}
	if req.TotalStorageMB != nil {
		device.TotalStorageMB = *req.TotalStorageMB
	}
	device.IsConnected = true
	if err := h.DB.Save(&device).Error; err != nil {
		respondError(c, http.StatusInternalServerError, 500, "failed to bind device")
		return
	}

	respondSuccess(c, device)
}

// UpdateDevice updates device attributes (e.g. name or online status)
func (h *DeviceHandler) UpdateDevice(c *gin.Context) {
	userID := c.GetString("userID")
	deviceID := c.Param("id")

	var req models.UpdateDeviceRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		respondError(c, http.StatusBadRequest, 400, "invalid input data")
		return
	}

	var device models.BoundDevice
	if err := h.DB.Where("id = ? AND user_id = ?", deviceID, userID).First(&device).Error; err != nil {
		respondError(c, http.StatusNotFound, 404, "device not found")
		return
	}

	if req.Name != nil {
		device.Name = *req.Name
	}
	if req.BatteryLevel != nil {
		device.BatteryLevel = *req.BatteryLevel
	}
	if req.IsConnected != nil {
		device.IsConnected = *req.IsConnected
	}
	if req.FirmwareVersion != nil {
		device.FirmwareVersion = *req.FirmwareVersion
	}
	if req.FreeStorageMB != nil {
		device.FreeStorageMB = *req.FreeStorageMB
	}
	if req.TotalStorageMB != nil {
		device.TotalStorageMB = *req.TotalStorageMB
	}

	if err := h.DB.Save(&device).Error; err != nil {
		respondError(c, http.StatusInternalServerError, 500, "failed to update device")
		return
	}

	respondSuccess(c, device)
}

// UnbindDevice unbinds a Spark device
func (h *DeviceHandler) UnbindDevice(c *gin.Context) {
	userID := c.GetString("userID")
	deviceID := c.Param("id")

	if err := h.DB.Where("id = ? AND user_id = ?", deviceID, userID).Delete(&models.BoundDevice{}).Error; err != nil {
		respondError(c, http.StatusInternalServerError, 500, "failed to unbind device")
		return
	}

	respondSuccess(c, gin.H{"deletedId": deviceID})
}