package iot

import (
	"context"
	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/dao"
	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/library/contexts"
	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/service"

	"github.com/gogf/gf/v2/frame/g"
)

type cardDeptDisplayNode struct {
	DeptID   int64  `orm:"dept_id"`
	ParentID int64  `orm:"parent_id"`
	DeptName string `orm:"dept_name"`
}

func newCardDeptDisplayResolver(ctx context.Context) (func(int64, string) string, error) {
	nodes, err := loadCardDeptDisplayNodes(ctx)
	if err != nil {
		return nil, err
	}
	viewerDeptID := contexts.GetDeptId(ctx)
	return func(cardDeptID int64, fallback string) string {
		return resolveCardDisplayDeptName(nodes, viewerDeptID, cardDeptID, fallback)
	}, nil
}

func loadCardDeptDisplayNodes(ctx context.Context) (map[int64]cardDeptDisplayNode, error) {
	nodes := make(map[int64]cardDeptDisplayNode)
	tenantID := contexts.GetTenantId(ctx)
	if tenantID == "" {
		return nodes, nil
	}

	var departments []*cardDeptDisplayNode
	mod := service.MemoryDB().DB(ctx).Ctx(ctx).Model(dao.SysDept.Table()).
		Fields(
			dao.SysDept.Columns().DeptId,
			dao.SysDept.Columns().ParentId,
			dao.SysDept.Columns().DeptName,
		).
		Where(dao.SysDept.Columns().TenantId, tenantID).
		WhereNull(dao.SysDept.Columns().DeletedAt)
	if err := mod.Scan(&departments); err != nil {
		return nil, err
	}
	for _, department := range departments {
		if department == nil || department.DeptID <= 0 {
			continue
		}
		nodes[department.DeptID] = *department
	}
	return nodes, nil
}

func resolveCardDisplayDeptName(
	nodes map[int64]cardDeptDisplayNode,
	viewerDeptID int64,
	cardDeptID int64,
	fallback string,
) string {
	cardDept, ok := nodes[cardDeptID]
	if !ok {
		return fallback
	}
	if viewerDeptID <= 0 || viewerDeptID == cardDeptID {
		return cardDept.DeptName
	}

	path := make([]int64, 0, 4)
	visited := make(map[int64]struct{})
	currentID := cardDeptID
	for currentID > 0 {
		if _, exists := visited[currentID]; exists {
			return fallback
		}
		visited[currentID] = struct{}{}
		path = append(path, currentID)

		current, exists := nodes[currentID]
		if !exists {
			return fallback
		}
		if currentID == viewerDeptID {
			if len(path) == 1 {
				return current.DeptName
			}
			return nodes[path[len(path)-2]].DeptName
		}
		currentID = current.ParentID
	}
	return fallback
}

func logCardDeptDisplayResolverError(ctx context.Context, err error) {
	if err != nil {
		g.Log().Warningf(ctx, "load card department display nodes failed: %v", err)
	}
}