package ui

import (
	"github.com/bwmarrin/discordgo"
	"github.com/rivo/tview"
)

// NewGuildsWidget creates and returns a new guilds widget.
func NewGuildsWidget() *tview.TreeView {
	w := tview.NewTreeView()
	w.
		SetTopLevel(1).
		SetRoot(tview.NewTreeNode("")).
		SetBorder(true).
		SetBorderPadding(0, 0, 1, 0).
		SetTitle("Guilds").
		SetTitleAlign(tview.AlignLeft)

	return w
}

// NewTextChannelTreeNode creates and returns a new text channel treenode.
func NewTextChannelTreeNode(c *discordgo.Channel) *tview.TreeNode {
	n := tview.NewTreeNode("[::d]#" + c.Name + "[::-]").
		SetReference(c.ID)

	return n
}

// GetTreeNodeByReference gets the TreeNode that has reference r from the given
// treeview.
func GetTreeNodeByReference(
	r interface{},
	treeV *tview.TreeView,
) (mn *tview.TreeNode) {
	treeV.GetRoot().Walk(func(n, _ *tview.TreeNode) bool {
		if n.GetReference() == r {
			mn = n
			return false
		}

		return true
	})

	return
}

// CreateTopLevelChannelsTreeNodes creates TreeNodes for the top-level (orphan)
// channels.
func CreateTopLevelChannelsTreeNodes(
	s *discordgo.State,
	n *tview.TreeNode,
	cs []*discordgo.Channel,
) {
	for _, c := range cs {
		if (c.Type == discordgo.ChannelTypeGuildText || c.Type == discordgo.ChannelTypeGuildNews) &&
			(c.ParentID == "") {
			if p, err := s.UserChannelPermissions(s.User.ID, c.ID); err != nil || p&discordgo.PermissionViewChannel != discordgo.PermissionViewChannel {
				continue
			}

			cn := NewTextChannelTreeNode(c)
			n.AddChild(cn)
			continue
		}
	}
}

// CreateCategoryChannelsTreeNodes creates TreeNodes for the category (parent)
// channels.
func CreateCategoryChannelsTreeNodes(
	s *discordgo.State,
	n *tview.TreeNode,
	cs []*discordgo.Channel,
) {
CategoryLoop:
	for _, c := range cs {
		if c.Type == discordgo.ChannelTypeGuildCategory {
			if p, err := s.UserChannelPermissions(s.User.ID, c.ID); err != nil || p&discordgo.PermissionViewChannel != discordgo.PermissionViewChannel {
				continue
			}

			for _, child := range cs {
				if child.ParentID == c.ID {
					cn := tview.NewTreeNode(c.Name).
						SetReference(c.ID)
					n.AddChild(cn)
					continue CategoryLoop
				}
			}

			cn := tview.NewTreeNode(c.Name).
				SetReference(c.ID)
			n.AddChild(cn)
		}
	}
}

// CreateSecondLevelChannelsTreeNodes creates TreeNodes for the second-level
// (category children) channels.
func CreateSecondLevelChannelsTreeNodes(
	s *discordgo.State,
	treeV *tview.TreeView,
	cs []*discordgo.Channel,
) {
	for _, c := range cs {
		if (c.Type == discordgo.ChannelTypeGuildText || c.Type == discordgo.ChannelTypeGuildNews) &&
			(c.ParentID != "") {
			if p, err := s.UserChannelPermissions(s.User.ID, c.ID); err != nil || p&discordgo.PermissionViewChannel != discordgo.PermissionViewChannel {
				continue
			}

			if pn := GetTreeNodeByReference(c.ParentID, treeV); pn != nil {
				cn := NewTextChannelTreeNode(c)
				pn.AddChild(cn)
			}
		}
	}
}