package models

import (
	"time"

	"gorm.io/gorm"
)

type Project struct {
	ID          uint             `json:"id" gorm:"primaryKey"`
	Name        string           `json:"name" gorm:"not null"`
	Description string           `json:"description"`
	GiteaOrg    string           `json:"gitea_org"`
	Status      string           `json:"status" gorm:"default:'planning'"`
	Priority    string           `json:"priority" gorm:"default:'medium'"`
	StartDate   *time.Time       `json:"start_date"`
	EndDate     *time.Time       `json:"end_date"`
	OwnerID     uint             `json:"owner_id"`
	Owner       User             `json:"owner" gorm:"foreignKey:OwnerID"`
	Members     []ProjectMember  `json:"members" gorm:"foreignKey:ProjectID"`
	Epics       []Epic           `json:"epics" gorm:"foreignKey:ProjectID"`
	Stories     []Story          `json:"stories" gorm:"foreignKey:ProjectID"`
	Tasks       []Task           `json:"tasks" gorm:"foreignKey:ProjectID"`
	Sprints     []Sprint         `json:"sprints" gorm:"foreignKey:ProjectID"`
	CreatedAt   time.Time        `json:"created_at"`
	UpdatedAt   time.Time        `json:"updated_at"`
}

type ProjectMember struct {
	ID        uint      `json:"id" gorm:"primaryKey"`
	ProjectID uint      `json:"project_id"`
	UserID    uint      `json:"user_id"`
	Role      string    `json:"role" gorm:"default:'developer'"`
	User      User      `json:"user" gorm:"foreignKey:UserID"`
	JoinedAt  time.Time `json:"joined_at"`
}

type ProjectStatus string

const (
	ProjectStatusActive   ProjectStatus = "active"
	ProjectStatusArchived ProjectStatus = "archived"
	ProjectStatusPlanning ProjectStatus = "planning"
)

type ProjectPriority string

const (
	PriorityLow      ProjectPriority = "low"
	PriorityMedium   ProjectPriority = "medium"
	PriorityHigh     ProjectPriority = "high"
	PriorityCritical ProjectPriority = "critical"
)

type ProjectMemberRole string

const (
	ProjectRoleOwner     ProjectMemberRole = "owner"
	ProjectRoleManager   ProjectMemberRole = "manager"
	ProjectRoleDeveloper ProjectMemberRole = "developer"
	ProjectRoleTester    ProjectMemberRole = "tester"
	ProjectRoleViewer    ProjectMemberRole = "viewer"
)

func (p *Project) BeforeCreate(tx *gorm.DB) error {
	return nil
}

func (p *Project) GetMembers() ([]User, error) {
	var users []User
	err := DB.Joins("JOIN project_members ON users.id = project_members.user_id").
		Where("project_members.project_id = ?", p.ID).
		Find(&users).Error
	return users, err
}

func (p *Project) AddMember(userID uint, role string) error {
	member := ProjectMember{
		ProjectID: p.ID,
		UserID:    userID,
		Role:      role,
		JoinedAt:  time.Now(),
	}
	return DB.Create(&member).Error
}

func (p *Project) RemoveMember(userID uint) error {
	return DB.Where("project_id = ? AND user_id = ?", p.ID, userID).Delete(&ProjectMember{}).Error
}

func (p *Project) GetProgress() (float64, error) {
	var totalTasks int64
	var completedTasks int64

	err := DB.Model(&Task{}).Where("project_id = ?", p.ID).Count(&totalTasks).Error
	if err != nil {
		return 0, err
	}

	if totalTasks == 0 {
		return 0, nil
	}

	err = DB.Model(&Task{}).Where("project_id = ? AND status = 'done'", p.ID).Count(&completedTasks).Error
	if err != nil {
		return 0, err
	}

	return float64(completedTasks) / float64(totalTasks) * 100, nil
}

func CreateProject(project *Project) error {
	return DB.Create(project).Error
}

func GetProjectByID(id uint) (*Project, error) {
	var project Project
	err := DB.Preload("Owner").Preload("Members.User").First(&project, id).Error
	return &project, err
}

func GetProjectsByUser(userID uint) ([]Project, error) {
	var projects []Project
	err := DB.Where("owner_id = ?", userID).
		Or("id IN (SELECT project_id FROM project_members WHERE user_id = ?)", userID).
		Preload("Owner").
		Find(&projects).Error
	return projects, err
}

func UpdateProject(project *Project) error {
	return DB.Save(project).Error
}

func DeleteProject(id uint) error {
	return DB.Delete(&Project{}, id).Error
}

func ListProjects(offset, limit int, filters map[string]interface{}) ([]Project, int64, error) {
	var projects []Project
	var total int64

	query := DB.Model(&Project{})
	
	for key, value := range filters {
		switch key {
		case "status":
			query = query.Where("status = ?", value)
		case "priority":
			query = query.Where("priority = ?", value)
		case "owner_id":
			query = query.Where("owner_id = ?", value)
		}
	}

	err := query.Count(&total).Error
	if err != nil {
		return nil, 0, err
	}

	err = query.Preload("Owner").Offset(offset).Limit(limit).Find(&projects).Error
	return projects, total, err
}