package model

import (
	"fmt"
)

type Node struct {
	Issue    Issue // Assuming Issue struct is imported or defined in the same package
	Children []*Node
}

// BuildTree builds a hierarchical tree of issues based on parent-child relationships.
func BuildTree(issues []Issue) []*Node {
	nodeMap := make(map[int]*Node, len(issues))
	for i := range issues {
		nodeMap[issues[i].ID] = &Node{Issue: issues[i]}
	}

	var roots []*Node
	for _, node := range nodeMap {
		if node.Issue.Parent == nil {
			roots = append(roots, node)
		} else {
			parent, ok := nodeMap[node.Issue.Parent.ID]
			if ok {
				parent.Children = append(parent.Children, node)
			} else {
				// Parent not in project scope → treat as root
				roots = append(roots, node)
			}
		}
	}
	return roots
}

// PrintTree prints the issue tree to standard output.
func PrintTree(nodes []*Node, prefix string, isLast bool) {
	for i, node := range nodes {
		last := i == len(nodes)-1
		connector := "├── "
		if last {
			connector = "└── "
		}

		parentInfo := ""
		if node.Issue.Parent != nil {
			parentInfo = fmt.Sprintf(" [parent: #%d]", node.Issue.Parent.ID)
		}

		fmt.Printf("%s%s#%d %s (%s)%s\n",
			prefix, connector,
			node.Issue.ID,
			node.Issue.Subject,
			node.Issue.Status.Title,
			parentInfo,
		)

		childPrefix := prefix
		if last {
			childPrefix += "    "
		} else {
			childPrefix += "│   "
		}

		PrintTree(node.Children, childPrefix, isLast)
	}
}