package routes

import (
	"dk/internal/components"
	"dk/internal/database"
	"dk/internal/helpers/markdown"
	"dk/internal/models/forum"
	"dk/internal/models/users"
	"fmt"
	"strings"

	sushi "git.sharkk.net/Sharkk/Sushi"
	"git.sharkk.net/Sharkk/Sushi/auth"
)

// ThreadInfo combines forum thread with author and last reply info
type ThreadInfo struct {
	Thread      *forum.Forum
	Author      *users.User
	LastReplyBy *users.User
}

// PostInfo combines a forum post/reply with its author
type PostInfo struct {
	Post   *forum.Forum
	Author *users.User
}

func RegisterForumRoutes(app *sushi.App) {
	authed := app.Group("/forum")
	authed.Use(auth.RequireAuth())
	authed.Get("/", index)
	authed.Get("/new", showNew)
	authed.Post("/new", new)
	authed.Get("/:id", showThread)
	authed.Get("/:id/reply", showReply)
	authed.Post("/:id/reply", reply)
}

func index(ctx sushi.Ctx) {
	page := int(ctx.QueryArgs().GetUintOrZero("page"))
	if page < 1 {
		page = 1
	}

	perPage := 30
	offset := (page - 1) * perPage

	// Get threads with pagination
	var threads []*forum.Forum
	err := database.Select(&threads, "SELECT * FROM forum WHERE parent = 0 ORDER BY last_post DESC, id DESC LIMIT %d OFFSET %d", perPage, offset)
	if err != nil {
		threads = make([]*forum.Forum, 0)
	}

	// Get total count for pagination
	var totalCount int
	database.Get(&totalCount, "SELECT COUNT(*) FROM forum WHERE parent = 0")

	// Build thread info with authors and last reply info
	var threadInfos []ThreadInfo
	for _, thread := range threads {
		author, _ := users.Find(thread.Author)
		if author == nil {
			author = &users.User{Username: "[Deleted]", ClassID: 1}
		}

		// Get last reply author if there are replies
		var lastReplyBy *users.User
		if thread.Replies > 0 {
			var lastReply forum.Forum
			err := database.Get(&lastReply, "SELECT * FROM forum WHERE parent = %d ORDER BY posted DESC LIMIT 1", thread.ID)
			if err == nil {
				lastReplyBy, _ = users.Find(lastReply.Author)
			}
		}

		threadInfos = append(threadInfos, ThreadInfo{
			Thread:      thread,
			Author:      author,
			LastReplyBy: lastReplyBy,
		})
	}

	totalPages := (totalCount + perPage - 1) / perPage

	components.RenderPage(ctx, "Forum", "forum/index.html", map[string]any{
		"threadInfos": threadInfos,
		"currentPage": page,
		"totalPages":  totalPages,
		"hasNext":     page < totalPages,
		"hasPrev":     page > 1,
	})
}

func showNew(ctx sushi.Ctx) {
	components.RenderPage(ctx, "New Forum Thread", "forum/new.html", map[string]any{})
}

func new(ctx sushi.Ctx) {
	sess := ctx.GetCurrentSession()

	title := strings.TrimSpace(ctx.Form("title").String())
	content := strings.TrimSpace(ctx.Form("content").String())

	if title == "" {
		sess.SetFlash("error", "Thread title cannot be empty")
		ctx.Redirect("/forum/new")
		return
	}

	if content == "" {
		sess.SetFlash("error", "Thread content cannot be empty")
		ctx.Redirect("/forum/new")
		return
	}

	user := ctx.GetCurrentUser().(*users.User)

	thread := forum.New()
	thread.Author = user.ID
	thread.Title = title
	thread.Content = content

	database.Transaction(func() error {
		return thread.Insert()
	})

	ctx.Redirect(fmt.Sprintf("/forum/%d", thread.ID))
}

func showThread(ctx sushi.Ctx) {
	sess := ctx.GetCurrentSession()
	id := ctx.Param("id").Int()
	page := int(ctx.QueryArgs().GetUintOrZero("page"))
	if page < 1 {
		page = 1
	}

	thread, err := forum.Find(id)
	if err != nil {
		sess.SetFlash("error", fmt.Sprintf("Forum thread %d not found", id))
		ctx.Redirect("/forum")
		return
	}

	if thread.Parent != 0 {
		sess.SetFlash("error", fmt.Sprintf("Forum post %d is not a thread", id))
		ctx.Redirect("/forum")
		return
	}

	// Get thread author
	threadAuthor, _ := users.Find(thread.Author)
	if threadAuthor == nil {
		threadAuthor = &users.User{Username: "[Deleted]", Level: 1, ClassID: 1}
	}

	// Get replies with pagination
	perPage := 30
	offset := (page - 1) * perPage

	var replies []*forum.Forum
	err = database.Select(&replies, "SELECT * FROM forum WHERE parent = %d ORDER BY posted ASC LIMIT %d OFFSET %d", id, perPage, offset)
	if err != nil {
		replies = make([]*forum.Forum, 0)
	}

	// Build reply info with authors
	var replyInfos []PostInfo
	for _, reply := range replies {
		author, _ := users.Find(reply.Author)
		if author == nil {
			author = &users.User{Username: "[Deleted]", Level: 1, ClassID: 1}
		}

		replyInfos = append(replyInfos, PostInfo{
			Post:   reply,
			Author: author,
		})
	}

	totalPages := (thread.Replies + perPage - 1) / perPage
	if totalPages < 1 {
		totalPages = 1
	}

	components.RenderPage(ctx, thread.Title, "forum/thread.html", map[string]any{
		"thread":       thread,
		"threadAuthor": threadAuthor,
		"replyInfos":   replyInfos,
		"currentPage":  page,
		"totalPages":   totalPages,
		"hasNext":      page < totalPages,
		"hasPrev":      page > 1,
		"markdown":     markdown.MarkdownToHTML,
	})
}

func showReply(ctx sushi.Ctx) {
	sess := ctx.GetCurrentSession()
	id := ctx.Param("id").Int()

	thread, err := forum.Find(id)
	if err != nil {
		sess.SetFlash("error", fmt.Sprintf("Forum thread %d not found", id))
		ctx.Redirect("/forum")
		return
	}

	if thread.Parent != 0 {
		sess.SetFlash("error", fmt.Sprintf("Forum post %d is not a thread", id))
		ctx.Redirect("/forum")
		return
	}

	components.RenderPage(ctx, "Reply to "+thread.Title, "forum/reply.html", map[string]any{
		"thread": thread,
	})
}

func reply(ctx sushi.Ctx) {
	sess := ctx.GetCurrentSession()
	id := ctx.Param("id").Int()

	thread, err := forum.Find(id)
	if err != nil {
		sess.SetFlash("error", fmt.Sprintf("Forum thread %d not found", id))
		ctx.Redirect("/forum")
		return
	}

	if thread.Parent != 0 {
		sess.SetFlash("error", fmt.Sprintf("Forum post %d is not a thread", id))
		ctx.Redirect("/forum")
		return
	}

	content := strings.TrimSpace(ctx.Form("content").String())
	if content == "" {
		sess.SetFlash("error", "Reply content cannot be empty")
		ctx.Redirect(fmt.Sprintf("/forum/%d/reply", id))
		return
	}

	user := ctx.GetCurrentUser().(*users.User)

	reply := forum.New()
	reply.Author = user.ID
	reply.Parent = thread.ID
	reply.Title = "Re: " + thread.Title
	reply.Content = content

	database.Transaction(func() error {
		if err := reply.Insert(); err != nil {
			return err
		}

		// Update thread reply count and last post time
		thread.IncrementReplies()
		thread.UpdateLastPost()

		return database.Exec("UPDATE forum SET replies = %d, last_post = %d WHERE id = %d",
			thread.Replies, thread.LastPost, thread.ID)
	})

	ctx.Redirect(fmt.Sprintf("/forum/%d", thread.ID))
}