package model

import (
	"time"

	"github.com/google/uuid"
)

// BaseModel provides common fields for all database models
type BaseModel struct {
	ID        string    `json:"id" gorm:"type:uuid;primary_key;default:gen_random_uuid()"`
	CreatedAt time.Time `json:"created_at" gorm:"not null;default:now()"`
	UpdatedAt time.Time `json:"updated_at" gorm:"not null;default:now()"`
}

// Init initializes base model with CreatedAt, UpdatedAt, and ID values
func (bm *BaseModel) Init() {
	now := time.Now().UTC()
	bm.ID = uuid.NewString()
	bm.CreatedAt = now
	bm.UpdatedAt = now
}

// UpdateTimestamp updates the UpdatedAt field
func (bm *BaseModel) UpdateTimestamp() {
	bm.UpdatedAt = time.Now().UTC()
}

// BeforeCreate is a GORM hook that runs before creating a record
func (bm *BaseModel) BeforeCreate() error {
	if bm.ID == "" {
		bm.Init()
	}
	return nil
}

// BeforeUpdate is a GORM hook that runs before updating a record
func (bm *BaseModel) BeforeUpdate() error {
	bm.UpdateTimestamp()
	return nil
}

// FilteredResponse represents a paginated response
type FilteredResponse struct {
	Items interface{} `json:"items"`
	Params
}

// MessageResponse represents a simple message response
type MessageResponse struct {
	Message string `json:"message"`
	Success bool   `json:"success"`
}

// ErrorResponse represents an error response
type ErrorResponse struct {
	Error   string                 `json:"error"`
	Details map[string]interface{} `json:"details,omitempty"`
	Code    int                    `json:"code,omitempty"`
}

// Params represents pagination and filtering parameters
type Params struct {
	SortBy       string `json:"sortBy" query:"sortBy"`
	SortOrder    string `json:"sortOrder" query:"sortOrder"`
	Page         int    `json:"page" query:"page"`
	Limit        int    `json:"limit" query:"limit"`
	Search       string `json:"search" query:"search"`
	Filter       string `json:"filter" query:"filter"`
	TotalRecords int64  `json:"totalRecords"`
	TotalPages   int    `json:"totalPages"`
}

// DefaultParams returns default pagination parameters
func DefaultParams() Params {
	return Params{
		Page:      1,
		Limit:     10,
		SortBy:    "created_at",
		SortOrder: "desc",
	}
}

// Validate validates and sets default values for parameters
func (p *Params) Validate() {
	if p.Page < 1 {
		p.Page = 1
	}
	if p.Limit < 1 || p.Limit > 100 {
		p.Limit = 10
	}
	if p.SortBy == "" {
		p.SortBy = "created_at"
	}
	if p.SortOrder != "asc" && p.SortOrder != "desc" {
		p.SortOrder = "desc"
	}
}

// Offset calculates the offset for database queries
func (p *Params) Offset() int {
	return (p.Page - 1) * p.Limit
}

// CalculateTotalPages calculates total pages based on total records
func (p *Params) CalculateTotalPages() {
	if p.Limit > 0 {
		p.TotalPages = int((p.TotalRecords + int64(p.Limit) - 1) / int64(p.Limit))
	}
}