package backups_config

import (
	"errors"
	"net/http"

	"github.com/gin-gonic/gin"
	"github.com/google/uuid"

	users_middleware "databasus-backend/internal/features/users/middleware"
)

type BackupConfigController struct {
	backupConfigService *BackupConfigService
}

func (c *BackupConfigController) RegisterRoutes(router *gin.RouterGroup) {
	router.POST("/backup-configs/save", c.SaveBackupConfig)
	router.GET("/backup-configs/database/:id", c.GetBackupConfigByDbID)
	router.GET("/backup-configs/storage/:id/is-using", c.IsStorageUsing)
	router.GET("/backup-configs/storage/:id/databases-count", c.CountDatabasesForStorage)
	router.POST("/backup-configs/database/:id/transfer", c.TransferDatabase)
}

// SaveBackupConfig
// @Summary Save backup configuration
// @Description Save or update backup configuration for a database. Encryption can be set to NONE (no encryption) or ENCRYPTED (AES-256-GCM encryption).
// @Tags backup-configs
// @Accept json
// @Produce json
// @Param request body BackupConfig true "Backup configuration data (encryption field: NONE or ENCRYPTED)"
// @Success 200 {object} BackupConfig "Returns the saved backup configuration including encryption settings"
// @Failure 400 {object} map[string]string "Invalid encryption value or other validation errors"
// @Failure 401 {object} map[string]string "User not authenticated"
// @Failure 500 {object} map[string]string "Internal server error"
// @Router /backup-configs/save [post]
func (c *BackupConfigController) SaveBackupConfig(ctx *gin.Context) {
	user, ok := users_middleware.GetUserFromContext(ctx)
	if !ok {
		ctx.JSON(http.StatusUnauthorized, gin.H{"error": "User not authenticated"})
		return
	}

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

	// make sure we rely on full .Storage object
	requestDTO.StorageID = nil

	savedConfig, err := c.backupConfigService.SaveBackupConfigWithAuth(user, &requestDTO)
	if err != nil {
		ctx.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	ctx.JSON(http.StatusOK, savedConfig)
}

// GetBackupConfigByDbID
// @Summary Get backup configuration by database ID
// @Description Get backup configuration for a specific database including encryption settings (NONE or ENCRYPTED)
// @Tags backup-configs
// @Produce json
// @Param id path string true "Database ID"
// @Success 200 {object} BackupConfig "Returns backup configuration with encryption field"
// @Failure 400 {object} map[string]string "Invalid database ID"
// @Failure 401 {object} map[string]string "User not authenticated"
// @Failure 404 {object} map[string]string "Backup configuration not found"
// @Router /backup-configs/database/{id} [get]
func (c *BackupConfigController) GetBackupConfigByDbID(ctx *gin.Context) {
	user, ok := users_middleware.GetUserFromContext(ctx)
	if !ok {
		ctx.JSON(http.StatusUnauthorized, gin.H{"error": "User not authenticated"})
		return
	}

	id, err := uuid.Parse(ctx.Param("id"))
	if err != nil {
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "invalid database ID"})
		return
	}

	backupConfig, err := c.backupConfigService.GetBackupConfigByDbIdWithAuth(user, id)
	if err != nil {
		ctx.JSON(http.StatusNotFound, gin.H{"error": "backup configuration not found"})
		return
	}

	ctx.JSON(http.StatusOK, backupConfig)
}

// IsStorageUsing
// @Summary Check if storage is being used
// @Description Check if a storage is currently being used by any backup configuration
// @Tags backup-configs
// @Produce json
// @Param id path string true "Storage ID"
// @Success 200 {object} map[string]bool
// @Failure 400
// @Failure 401
// @Failure 500
// @Router /backup-configs/storage/{id}/is-using [get]
func (c *BackupConfigController) IsStorageUsing(ctx *gin.Context) {
	user, ok := users_middleware.GetUserFromContext(ctx)
	if !ok {
		ctx.JSON(http.StatusUnauthorized, gin.H{"error": "User not authenticated"})
		return
	}

	id, err := uuid.Parse(ctx.Param("id"))
	if err != nil {
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "invalid storage ID"})
		return
	}

	isUsing, err := c.backupConfigService.IsStorageUsing(user, id)
	if err != nil {
		ctx.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	ctx.JSON(http.StatusOK, gin.H{"isUsing": isUsing})
}

// CountDatabasesForStorage
// @Summary Count databases using a storage
// @Description Get the count of databases that are using a specific storage
// @Tags backup-configs
// @Produce json
// @Param id path string true "Storage ID"
// @Success 200 {object} map[string]int
// @Failure 400
// @Failure 401
// @Failure 500
// @Router /backup-configs/storage/{id}/databases-count [get]
func (c *BackupConfigController) CountDatabasesForStorage(ctx *gin.Context) {
	user, ok := users_middleware.GetUserFromContext(ctx)
	if !ok {
		ctx.JSON(http.StatusUnauthorized, gin.H{"error": "User not authenticated"})
		return
	}

	id, err := uuid.Parse(ctx.Param("id"))
	if err != nil {
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "invalid storage ID"})
		return
	}

	count, err := c.backupConfigService.CountDatabasesForStorage(user, id)
	if err != nil {
		ctx.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	ctx.JSON(http.StatusOK, gin.H{"count": count})
}

// TransferDatabase
// @Summary Transfer database to another workspace
// @Description Transfer a database from one workspace to another. Can transfer to a new storage or transfer with the existing storage. Can also specify target notifiers from the target workspace.
// @Tags backup-configs
// @Accept json
// @Produce json
// @Param id path string true "Database ID"
// @Param request body TransferDatabaseRequest true "Transfer request with targetWorkspaceId, storage options (targetStorageId or isTransferWithStorage), and optional targetNotifierIds"
// @Success 200 {object} map[string]string "Database transferred successfully"
// @Failure 400 {object} map[string]string "Invalid request, target storage/notifier not in target workspace, or transfer failed"
// @Failure 401 {object} map[string]string "User not authenticated"
// @Failure 403 {object} map[string]string "Insufficient permissions"
// @Router /backup-configs/database/{id}/transfer [post]
func (c *BackupConfigController) TransferDatabase(ctx *gin.Context) {
	user, ok := users_middleware.GetUserFromContext(ctx)
	if !ok {
		ctx.JSON(http.StatusUnauthorized, gin.H{"error": "User not authenticated"})
		return
	}

	id, err := uuid.Parse(ctx.Param("id"))
	if err != nil {
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "invalid database ID"})
		return
	}

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

	if request.TargetWorkspaceID == uuid.Nil {
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "targetWorkspaceId is required"})
		return
	}

	if err := c.backupConfigService.TransferDatabaseToWorkspace(user, id, &request); err != nil {
		if errors.Is(err, ErrInsufficientPermissionsInSourceWorkspace) ||
			errors.Is(err, ErrInsufficientPermissionsInTargetWorkspace) {
			ctx.JSON(http.StatusForbidden, gin.H{"error": err.Error()})
			return
		}
		ctx.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	ctx.JSON(http.StatusOK, gin.H{"message": "database transferred successfully"})
}