package main

import (
	"strings"
	tea "github.com/charmbracelet/bubbletea"
	te "github.com/muesli/termenv"
	"github.com/charmbracelet/bubbles/textinput"
)

type chatModel struct {
	scroll		int
	chatInput	textinput.Model
}

func doSendMessage(conn *loungeConnection, channel int, text string) tea.Cmd {
	return func() tea.Msg {
		loungeChannelSend(conn, channel, text)
		return 1
	}
}

func getMessageString(channelName string, message loungeMessage) string {
	timestamp := message.Time[11:16]
	switch message.Type {
	case messageMessage, messageNotice:
		if message.From.Nick == "" {
			return timestamp + " " + message.Text + "\n"
		} else {
			return timestamp + " <" + message.From.Mode + message.From.Nick + "> " + message.Text + "\n"
		}
	case messageAction:
		return timestamp + " " + te.String(message.From.Mode + message.From.Nick + " " + message.Text).Italic().String() + "\n"
	case messageTopic:
		return timestamp + " " + te.String(message.From.Mode + message.From.Nick + " changed the topic to: " + message.Text).Italic().String() + "\n"
	case messageError:
		return timestamp + " " + te.String(message.Text).Foreground(color(errorColor)).String() + "\n"
	}
	return ""
}

func getMessageCounts(m mainModel) (int, int, int) {
	maxMessages := m.height - 2
	messageCount := maxMessages
	if messageCount > len(m.conn.Channel.Filtered) {
		messageCount = len(m.conn.Channel.Filtered)
	}
	maxScroll := len(m.conn.Channel.Filtered) - messageCount
	return maxMessages, messageCount, maxScroll
}

func chatModelInit() chatModel {
	input := textinput.NewModel()
	input.Placeholder = "Enter a chat message"
	input.CharLimit = 256
	input.Focus()
	return chatModel{0, input}
}

func (m mainModel) chatInit() tea.Cmd {
	return nil
}

func (m mainModel) chatView() string {
	channel := m.conn.Channel
	if channel == nil {
		return "No channel open"
	}
	s := te.String(channel.Name).Reverse().String() + " "
	maxTopicLen := m.width - len(channel.Name) - 1
	if maxTopicLen < 3 {
		s += "\n"
	} else if len(channel.Topic) <= maxTopicLen {
		s += highlightText(channel.Topic) + "\n"
	} else {
		s += highlightText(channel.Topic[:maxTopicLen-3] + "...") + "\n"
	}
	maxMessages, messageCount, maxScroll := getMessageCounts(m)
	if m.chatModel.scroll > maxScroll {
		m.chatModel.scroll = maxScroll
	}
	for i := 0; i < messageCount; i++ {
		index := len(channel.Filtered) - messageCount - m.chatModel.scroll + i
		s += getMessageString(channel.Name, channel.Filtered[index])
	}
	s += strings.Repeat("\n", maxMessages - messageCount)
	s += m.chatModel.chatInput.View()
	return s
}

func (m mainModel) chatUpdate(msg tea.Msg) (tea.Model, tea.Cmd) {
	var (
		cmd  tea.Cmd
		cmds []tea.Cmd
	)
	switch msg := msg.(type) {
	case tea.KeyMsg:
		if msg.Type == tea.KeyEnter && m.chatModel.chatInput.Value() != "" {
			cmd = doSendMessage(m.conn, m.conn.Channel.Id, m.chatModel.chatInput.Value())
			cmds = append(cmds, cmd)
			m.chatModel.chatInput.SetValue("")
		}
		_, _, maxScroll := getMessageCounts(m)
		if m.chatModel.scroll > maxScroll {
			m.chatModel.scroll = maxScroll
		}
		if msg.Type == tea.KeyUp {
			m.chatModel.scroll += 1
		}
		if msg.Type == tea.KeyDown && m.chatModel.scroll > 0 {
			m.chatModel.scroll -= 1
		}
	}
	m.chatModel.chatInput, cmd = m.chatModel.chatInput.Update(msg)
	cmds = append(cmds, cmd)
	return m, tea.Batch(cmds...)
}