package netbox

import (
	"context"
	"fmt"

	nb "github.com/netbox-community/go-netbox/v4"
)

// ParseCustomFields maps NetBox's map[string]interface{} custom fields response
// to the typed CustomFields struct. NetBox returns values as interface{} — we
// perform safe type assertions for each expected field.
func ParseCustomFields(raw map[string]interface{}) CustomFields {
	cf := CustomFields{}
	if raw == nil {
		return cf
	}

	if v, ok := raw["hw_id"].(string); ok {
		cf.HWID = v
	}
	if v, ok := raw["catalog_status"].(string); ok {
		cf.CatalogStatus = v
	}
	if v, ok := raw["product_url"].(string); ok {
		cf.ProductURL = v
	}
	if v, ok := raw["firmware_version"].(string); ok {
		cf.FirmwareVersion = v
	}
	if v, ok := raw["test_date"].(string); ok {
		cf.TestDate = v
	}
	if v, ok := raw["test_data"].(string); ok {
		cf.TestData = v
	}
	if v, ok := raw["ai_notes"].(string); ok {
		cf.AINotes = v
	}
	// photo_urls is a multi-value field — NetBox returns []interface{}
	if v, ok := raw["photo_urls"].([]interface{}); ok {
		urls := make([]string, 0, len(v))
		for _, u := range v {
			if s, ok := u.(string); ok {
				urls = append(urls, s)
			}
		}
		cf.PhotoURLs = urls
	}

	return cf
}

// BuildCustomFieldsPatch constructs the flat map[string]interface{} payload
// required by NetBox PATCH endpoints. Only include fields that are non-empty
// to avoid accidentally clearing existing values.
//
// NetBox custom field write format differs from read format:
//   - Text/URL/date fields: send string value directly
//   - Selection fields (catalog_status): send the choice value as string
//   - Multi-value fields (photo_urls): send []string directly
func BuildCustomFieldsPatch(hwID, catalogStatus string, photoURLs []string) map[string]interface{} {
	patch := make(map[string]interface{})
	if hwID != "" {
		patch["hw_id"] = hwID
	}
	if catalogStatus != "" {
		patch["catalog_status"] = catalogStatus
	}
	if len(photoURLs) > 0 {
		patch["photo_urls"] = photoURLs
	}
	return patch
}

// BuildFullCustomFieldsPatch constructs a patch with all custom fields.
// Use for initial record creation where all fields should be set.
func BuildFullCustomFieldsPatch(cf CustomFields) map[string]interface{} {
	patch := make(map[string]interface{})
	if cf.HWID != "" {
		patch["hw_id"] = cf.HWID
	}
	if cf.CatalogStatus != "" {
		patch["catalog_status"] = cf.CatalogStatus
	}
	if cf.ProductURL != "" {
		patch["product_url"] = cf.ProductURL
	}
	if cf.FirmwareVersion != "" {
		patch["firmware_version"] = cf.FirmwareVersion
	}
	if cf.TestDate != "" {
		patch["test_date"] = cf.TestDate
	}
	if cf.TestData != "" {
		patch["test_data"] = cf.TestData
	}
	if cf.AINotes != "" {
		patch["ai_notes"] = cf.AINotes
	}
	if len(cf.PhotoURLs) > 0 {
		patch["photo_urls"] = cf.PhotoURLs
	}
	return patch
}

// PatchCustomFields updates the custom fields of a device identified by deviceID.
// Uses go-netbox v4 PatchedWritableDeviceWithConfigContextRequest to send a partial update.
func (c *Client) PatchCustomFields(ctx context.Context, deviceID int64, patch map[string]interface{}) error {
	patchReq := nb.PatchedWritableDeviceWithConfigContextRequest{}
	patchReq.SetCustomFields(patch)

	_, _, err := c.api.DcimAPI.DcimDevicesPartialUpdate(ctx, int32(deviceID)).
		PatchedWritableDeviceWithConfigContextRequest(patchReq).Execute()
	if err != nil {
		return fmt.Errorf("patch custom fields for device %d: %w", deviceID, err)
	}
	return nil
}