package tui

import (
	"encoding/base64"
	"fmt"
	"log"
	"strings"
	"time"

	"whspbrd/pkg/cell_size"
	"whspbrd/pkg/clean_image"
	"whspbrd/pkg/render_image"

	"github.com/jroimartin/gocui"
)

const (
	chatViewColumn      = 23
	userIconPath        = "./configs/icon.png"
	contactIconPathFmt  = "./configs/servers/default/users/%s/icon.png"
	messageRowOffset    = 2
	messageRowIncrement = 3
)

func updateChatView(v *gocui.View) {
	v.Clear()

	clear := cleanimage.NewKittyImageCleaner()
	fmt.Print(clear.DeleteByColumn(chatViewColumn, false))

	// Check if we have valid users
	if len(users) == 0 || selectedUserIdx >= len(users) {
		return
	}

	// Ensure selectedMessageIdx is within bounds
	if len(chatData.Messages) == 0 {
		return
	}
	if selectedMessageIdx < 0 {
		selectedMessageIdx = 0
	}
	if selectedMessageIdx >= len(chatData.Messages) {
		selectedMessageIdx = len(chatData.Messages) - 1
	}

	// Get view dimensions
	_, viewHeight := v.Size()

	// Calculate which messages should be visible
	// We want to show the selected message in the middle of the view when possible
	messagesPerView := viewHeight / messageRowIncrement
	if messagesPerView <= 0 {
		messagesPerView = 1
	}

	// Calculate start index - show newest messages at bottom
	startIdx := max(0, min(selectedMessageIdx-(messagesPerView/2), len(chatData.Messages)-messagesPerView))

	// Calculate scroll offset to position view correctly
	scrollOffset := startIdx * messageRowIncrement
	ox, _ := v.Origin()
	v.SetOrigin(ox, scrollOffset)

	// Get terminal cell size once for all messages
	w, h, err := cell_size.GetTerminalCellSizePixels()
	if err != nil {
		log.Println("Error getting terminal cell size:", err)
		w, h = 10, 20 // fallback values
	}
	if h > w {
		h = h * 2
		w = 0
	} else {
		w = w*3 - (w / 10)
		h = 0
	}

	// Render only visible messages
	endIdx := min(startIdx+messagesPerView+1, len(chatData.Messages))
	for i := startIdx; i < endIdx; i++ {
		msg := chatData.Messages[i]
		decoded, err := base64.StdEncoding.DecodeString(msg.Content)
		if err != nil {
			log.Printf("Error decoding message: %v", err)
			continue
		}
		decoded = []byte(strings.TrimSuffix(string(decoded), "\n"))

		t, err := time.Parse(time.RFC3339, msg.Timestamp)
		if err != nil {
			log.Printf("Error parsing timestamp: %v", err)
			t = time.Now() // fallback to current time
		}
		formattedTime := t.Format("2006-01-02 15:04")

		// Determine if this is a message from the user or the contact
		isUserMessage := !strings.EqualFold(msg.Sender, users[selectedUserIdx])
		var senderLabel string
		var iconPath string

		if isUserMessage {
			senderLabel = Colors.Text(Colors.Base02) + "You (" + formattedTime + "):" + Colors.Reset
			iconPath = userIconPath
		} else {
			senderLabel = Colors.Text(Colors.Base05) + msg.Sender + " (" + formattedTime + "):" + Colors.Reset
			iconPath = fmt.Sprintf(contactIconPathFmt, strings.ToLower(msg.Sender))
		}

		// Highlight selected message
		prefix := "\t\t\t\t\t"
		if i == selectedMessageIdx {
			prefix = "\x1b[7m\t\t\t\t\t"
			senderLabel = senderLabel + "\x1b[0m\x1b[7m"
			decoded = append([]byte("\x1b[0m\x1b[7m"), decoded...)
			decoded = append(decoded, []byte("\x1b[0m")...)
		}

		// Print message text
		fmt.Fprintf(v, "%s", prefix+senderLabel+"\n"+prefix+string(decoded)+"\n\n")

		// Calculate row position for image rendering
		rowPosition := i*messageRowIncrement + messageRowOffset - scrollOffset

		// Only render images that are visible in the view
		if rowPosition >= 0 && rowPosition < viewHeight {
			render_image.RenderImage(iconPath, rowPosition, chatViewColumn, w, h, false)
		}
	}
}

func sendMessage(g *gocui.Gui, v *gocui.View) error {
	if len(users) == 0 || selectedUserIdx >= len(users) {
		return nil
	}

	input := v.Buffer()
	v.Clear()
	v.SetCursor(0, 0)
	v.SetOrigin(0, 0)

	if err := WriteMessage(users[selectedUserIdx], "You", users[selectedUserIdx], input); err != nil {
		log.Printf("Error writing message: %v", err)
		return err
	}
	LoadMessages(users[selectedUserIdx])

	chatView, err := g.View("chat")
	if err != nil {
		log.Printf("Error getting chat view: %v", err)
		return err
	}

	// Select newest message (at the end)
	if len(chatData.Messages) > 0 {
		selectedMessageIdx = len(chatData.Messages) - 1
	}
	updateChatView(chatView)
	return nil
}

func scrollChatUp(g *gocui.Gui, v *gocui.View) error {
	if len(chatData.Messages) == 0 {
		return nil
	}

	chatView, err := g.View("chat")
	if err != nil {
		return err
	}

	// Move selection up (to older messages)
	if selectedMessageIdx > 0 {
		selectedMessageIdx--
		updateChatView(chatView)
	}
	return nil
}

func scrollChatDown(g *gocui.Gui, v *gocui.View) error {
	if len(chatData.Messages) == 0 {
		return nil
	}

	chatView, err := g.View("chat")
	if err != nil {
		return err
	}

	// Move selection down (to newer messages)
	if selectedMessageIdx < len(chatData.Messages)-1 {
		selectedMessageIdx++
		updateChatView(chatView)
	}
	return nil
}