package flow_definition

import (
	"approveflow/app/base"
	"approveflow/app/provider/abstract/connect"
	"approveflow/app/utils"
	"encoding/json"
	"fmt"
)

// ApprovalFlow 审批流程表
type ApprovalFlow struct {
	ID          int64                           `gorm:"primaryKey;autoIncrement" json:"id"`                         // 主键ID
	Name        string                          `gorm:"type:varchar(100);not null" json:"name"`                     // 流程名称
	Description string                          `gorm:"type:text" json:"description"`                               // 流程描述
	Steps       []*ApprovalStep                 `gorm:"foreignKey:FlowID;constraint:OnDelete:CASCADE" json:"steps"` // 流程步骤
	NodeMap     map[string]connect.AbstractNode `gorm:"-" json:"node_map"`                                          // 流程步骤
	TenantKey   string                          `gorm:"type:varchar(50);not null" json:"tenant_key"`
	base.Model                                  // 通用字段，包括创建时间、更新时间等
}

func (flow *ApprovalFlow) GetNodes() []connect.AbstractNode {
	return utils.ConvertToAbstractNodes(flow.Steps, func(step *ApprovalStep) connect.AbstractNode {
		return step
	})
}

func (flow *ApprovalFlow) SetNodes(nodes []connect.AbstractNode) {
	steps := make([]*ApprovalStep, len(nodes))
	for i, node := range nodes {
		// 类型断言，将 abstract.AbstractNode 转换为 *ApprovalStep
		if step, ok := node.(*ApprovalStep); ok {
			steps[i] = step
		} else {
			// 如果转换失败，可以选择处理错误，抛出异常或记录日志
			panic("node is not of type *ApprovalStep")
		}
	}
	flow.Steps = steps
}

func (flow *ApprovalFlow) GetNodeMap() map[string]connect.AbstractNode {
	if flow.NodeMap == nil {
		flow.NodeMap = map[string]connect.AbstractNode{}
		connect.InitializeNodeMap(flow)
	}
	return flow.NodeMap
}

func (flow *ApprovalFlow) NewNodePathConfig(fromNodeKey, toNodeKey string) connect.AbstractNodePathConfig {
	return NewPathConfig(fromNodeKey, toNodeKey)
}

func (flow *ApprovalFlow) MarshalBinary() ([]byte, error) {
	return json.Marshal(flow)
}

func (flow *ApprovalFlow) UnmarshalBinary(data []byte) error {
	return json.Unmarshal(data, flow)
}

func NewApprovalFlow(name string, description string) *ApprovalFlow {
	approvalFlow := &ApprovalFlow{
		Name:        name,
		Description: description,
		Steps:       make([]*ApprovalStep, 0),
	}
	startStep := NewStartStep()
	endStep := NewEndStep()

	connect.InsertNodeFirst(approvalFlow, startStep)
	err := connect.InsertNodeAfter(approvalFlow, startStep, endStep)
	//path := NewPathBetween(startStep, endStep)
	//err := startStep.AddPathConfig(path)
	//err = approvalFlow.AddStep(startStep)
	//err = approvalFlow.AddStep(endStep)
	if err != nil {
		return nil
	}
	return approvalFlow
}

// AddStep 添加审批步骤
func (flow *ApprovalFlow) AddStep(step *ApprovalStep) error {
	// 检查步骤是否已存在
	for _, s := range flow.Steps {
		if s.ID == step.ID && 0 != step.ID {
			return fmt.Errorf("step with ID %d already exists in flow", step.ID)
		}
	}
	step.FlowID = flow.ID
	flow.Steps = append(flow.Steps, step)
	return nil
}

// RemoveStep 删除审批步骤
func (flow *ApprovalFlow) RemoveStep(stepID int64) error {
	for i, s := range flow.Steps {
		if s.ID == stepID {
			flow.Steps = append(flow.Steps[:i], flow.Steps[i+1:]...)
			return nil
		}
	}
	return fmt.Errorf("step with ID %d not found in flow", stepID)
}

// GetStep 获取审批步骤
func (flow *ApprovalFlow) GetStep(stepID int64) (*ApprovalStep, error) {
	for _, s := range flow.Steps {
		if s.ID == stepID {
			return s, nil
		}
	}
	return nil, fmt.Errorf("step with ID %d not found in flow", stepID)
}

func (flow *ApprovalFlow) GetStepByKey(key string) (*ApprovalStep, error) {
	for _, s := range flow.Steps {
		if s.Key == key {
			return s, nil
		}
	}
	return nil, fmt.Errorf("step with key %s not found in flow", key)
}

// ReorderSteps 重新排序步骤
func (flow *ApprovalFlow) ReorderSteps(order []int64) error {
	if len(order) != len(flow.Steps) {
		return fmt.Errorf("order length %d does not match steps length %d", len(order), len(flow.Steps))
	}
	stepMap := make(map[int64]*ApprovalStep)
	for i := range flow.Steps {
		stepMap[flow.Steps[i].ID] = flow.Steps[i]
	}
	var newSteps []*ApprovalStep
	for _, id := range order {
		if step, exists := stepMap[id]; exists {
			newSteps = append(newSteps, step)
		} else {
			return fmt.Errorf("step ID %d not found in flow", id)
		}
	}
	flow.Steps = newSteps
	return nil
}

// Validate 验证流程的完整性和正确性
func (flow *ApprovalFlow) Validate() error {
	if len(flow.Steps) == 0 {
		return fmt.Errorf("approval flow must have at least one step")
	}
	// 可以添加更多验证逻辑，如检查步骤的顺序、路径配置等
	return nil
}

// FirstStep 获取审批流程中的第一个审批节点
func (flow *ApprovalFlow) FirstStep() (*ApprovalStep, error) {
	for _, step := range flow.Steps {
		if step.StepCode == StepStart {
			return step, nil
		}
	}
	return nil, fmt.Errorf("no starting approval step found")
}