package routes

import (
	"database/sql"
	"encoding/json"
	"errors"
	"net/http"
	"strconv"
	"strings"

	c "git.tuxpa.in/a/gosora/common"
	"git.tuxpa.in/a/gosora/common/counters"
	p "git.tuxpa.in/a/gosora/common/phrases"
	qgen "git.tuxpa.in/a/gosora/query_gen"
)

type ReplyStmts struct {
    createReplyPaging *sql.Stmt
}

var replyStmts ReplyStmts

// TODO: Move this statement somewhere else
func init() {
    c.DbInits.Add(func(acc *qgen.Accumulator) error {
        replyStmts = ReplyStmts{
            createReplyPaging: acc.Select("replies").Cols("rid").Where("rid >= ? - 1 AND tid=?").Orderby("rid ASC").Prepare(),
        }
        return acc.FirstError()
    })
}

type JsonReply struct {
    Content string
}

func CreateReplySubmit(w http.ResponseWriter, r *http.Request, user *c.User) c.RouteError {
    // TODO: Use this
    js := r.FormValue("js") == "1"
    tid, err := strconv.Atoi(r.PostFormValue("tid"))
    if err != nil {
        return c.PreErrorJSQ("Failed to convert the Topic ID", w, r, js)
    }
    topic, err := c.Topics.Get(tid)
    if err == sql.ErrNoRows {
        return c.PreErrorJSQ("Couldn't find the parent topic", w, r, js)
    } else if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }

    // TODO: Add hooks to make use of headerLite
    lite, ferr := c.SimpleForumUserCheck(w, r, user, topic.ParentID)
    if ferr != nil {
        return ferr
    }
    if !user.Perms.ViewTopic || !user.Perms.CreateReply {
        return c.NoPermissionsJSQ(w, r, user, js)
    }
    if topic.IsClosed && !user.Perms.CloseTopic {
        return c.NoPermissionsJSQ(w, r, user, js)
    }

    content := c.PreparseMessage(r.PostFormValue("content"))
    // TODO: Fully parse the post and put that in the parsed column
    rid, err := c.Rstore.Create(topic, content, user.GetIP(), user.ID)
    if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }

    reply, err := c.Rstore.Get(rid)
    if err != nil {
        return c.LocalErrorJSQ("Unable to load the reply", w, r, user, js)
    }

    // Handle the file attachments
    // TODO: Stop duplicating this code
    if user.Perms.UploadFiles {
        _, rerr := uploadAttachment(w, r, user, topic.ParentID, "forums", rid, "replies", strconv.Itoa(topic.ID))
        if rerr != nil {
            return rerr
        }
    }

    if r.PostFormValue("has_poll") == "1" {
        maxPollOptions := 10
        pollInputItems := make(map[int]string)
        for key, values := range r.Form {
            //c.DebugDetail("key: ", key)
            //c.DebugDetailf("values: %+v\n", values)
            if !strings.HasPrefix(key, "pollinputitem[") {
                continue
            }
            halves := strings.Split(key, "[")
            if len(halves) != 2 {
                return c.LocalErrorJSQ("Malformed pollinputitem", w, r, user, js)
            }
            halves[1] = strings.TrimSuffix(halves[1], "]")

            index, err := strconv.Atoi(halves[1])
            if err != nil {
                return c.LocalErrorJSQ("Malformed pollinputitem", w, r, user, js)
            }
            for _, value := range values {
                // If there are duplicates, then something has gone horribly wrong, so let's ignore them, this'll likely happen during an attack
                _, exists := pollInputItems[index]
                // TODO: Should we use SanitiseBody instead to keep the newlines?
                if !exists && len(c.SanitiseSingleLine(value)) != 0 {
                    pollInputItems[index] = c.SanitiseSingleLine(value)
                    if len(pollInputItems) >= maxPollOptions {
                        break
                    }
                }
            }
        }

        // Make sure the indices are sequential to avoid out of bounds issues
        seqPollInputItems := make(map[int]string)
        for i := 0; i < len(pollInputItems); i++ {
            seqPollInputItems[i] = pollInputItems[i]
        }

        pollType := 0 // Basic single choice
        _, err := c.Polls.Create(reply, pollType, seqPollInputItems)
        if err != nil {
            return c.LocalErrorJSQ("Failed to add poll to reply", w, r, user, js) // TODO: Might need to be an internal error as it could leave phantom polls?
        }
    }
    _ = c.Rstore.GetCache().Remove(reply.ID)

    err = c.Forums.UpdateLastTopic(tid, user.ID, topic.ParentID)
    if err != nil && err != sql.ErrNoRows {
        return c.InternalErrorJSQ(err, w, r, js)
    }

    c.AddActivityAndNotifyAll(c.Alert{ActorID: user.ID, TargetUserID: topic.CreatedBy, Event: "reply", ElementType: "topic", ElementID: tid, Extra: strconv.Itoa(rid)})
    if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }

    err = user.IncreasePostStats(c.WordCount(content), false)
    if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }

    nTopic, err := c.Topics.Get(tid)
    if err == sql.ErrNoRows {
        return c.PreErrorJSQ("Couldn't find the parent topic", w, r, js)
    } else if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }
    page := c.LastPage(nTopic.PostCount, c.Config.ItemsPerPage)

    rows, err := replyStmts.createReplyPaging.Query(reply.ID, topic.ID)
    if err != nil && err != sql.ErrNoRows {
        return c.InternalErrorJSQ(err, w, r, js)
    }
    defer rows.Close()

    var rids []int
    for rows.Next() {
        var rid int
        if err := rows.Scan(&rid); err != nil {
            return c.InternalErrorJSQ(err, w, r, js)
        }
        rids = append(rids, rid)
    }
    if err := rows.Err(); err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }
    if len(rids) == 0 {
        return c.NotFoundJSQ(w, r, nil, js)
    }

    if page > 1 {
        var offset int
        if rids[0] == reply.ID {
            offset = 1
        } else if len(rids) == 2 && rids[1] == reply.ID {
            offset = 2
        }
        page = c.LastPage(nTopic.PostCount-(len(rids)+offset), c.Config.ItemsPerPage)
    }

    counters.PostCounter.Bump()
    skip, rerr := lite.Hooks.VhookSkippable("action_end_create_reply", reply.ID, user)
    if skip || rerr != nil {
        return rerr
    }

    prid, _ := strconv.Atoi(r.FormValue("prid"))
    if js && (prid == 0 || rids[0] == prid) {
        outBytes, err := json.Marshal(JsonReply{c.ParseMessage(reply.Content, topic.ParentID, "forums", user.ParseSettings, user)})
        if err != nil {
            return c.InternalErrorJSQ(err, w, r, js)
        }
        w.Write(outBytes)
    } else {
        var spage string
        if page > 1 {
            spage = "?page=" + strconv.Itoa(page)
        }
        http.Redirect(w, r, "/topic/"+strconv.Itoa(tid)+spage+"#post-"+strconv.Itoa(reply.ID), http.StatusSeeOther)
    }
    return nil
}

// TODO: Disable stat updates in posts handled by plugin_guilds
// TODO: Update the stats after edits so that we don't under or over decrement stats during deletes
func ReplyEditSubmit(w http.ResponseWriter, r *http.Request, u *c.User, srid string) c.RouteError {
    js := r.PostFormValue("js") == "1"
    reply, topic, lite, ferr := ReplyActPre(w, r, u, srid, js)
    if ferr != nil {
        return ferr
    }
    if !u.Perms.ViewTopic || !u.Perms.EditReply {
        return c.NoPermissionsJSQ(w, r, u, js)
    }
    if topic.IsClosed && !u.Perms.CloseTopic {
        return c.NoPermissionsJSQ(w, r, u, js)
    }

    err := reply.SetPost(r.PostFormValue("edit_item"))
    if err == sql.ErrNoRows {
        return c.PreErrorJSQ("The parent topic doesn't exist.", w, r, js)
    } else if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }
    if !c.Rstore.Exists(reply.ID) {
        return c.PreErrorJSQ("The updated reply doesn't exist.", w, r, js)
    }

    skip, rerr := lite.Hooks.VhookSkippable("action_end_edit_reply", reply.ID, u)
    if skip || rerr != nil {
        return rerr
    }

    if !js {
        http.Redirect(w, r, "/topic/"+strconv.Itoa(topic.ID)+"#reply-"+strconv.Itoa(reply.ID), http.StatusSeeOther)
    } else {
        outBytes, err := json.Marshal(JsonReply{c.ParseMessage(reply.Content, topic.ParentID, "forums", u.ParseSettings, u)})
        if err != nil {
            return c.InternalErrorJSQ(err, w, r, js)
        }
        w.Write(outBytes)
    }

    return nil
}

// TODO: Refactor this
// TODO: Disable stat updates in posts handled by plugin_guilds
func ReplyDeleteSubmit(w http.ResponseWriter, r *http.Request, u *c.User, srid string) c.RouteError {
    js := r.PostFormValue("js") == "1"
    reply, _, lite, ferr := ReplyActPre(w, r, u, srid, js)
    if ferr != nil {
        return ferr
    }
    if reply.CreatedBy != u.ID {
        if !u.Perms.ViewTopic || !u.Perms.DeleteReply {
            return c.NoPermissionsJSQ(w, r, u, js)
        }
    }
    if e := reply.Delete(); e != nil {
        return c.InternalErrorJSQ(e, w, r, js)
    }

    skip, rerr := lite.Hooks.VhookSkippable("action_end_delete_reply", reply.ID, u)
    if skip || rerr != nil {
        return rerr
    }

    //log.Printf("Reply #%d was deleted by c.User #%d", rid, u.ID)
    if !js {
        http.Redirect(w, r, "/topic/"+strconv.Itoa(reply.ParentID), http.StatusSeeOther)
    } else {
        w.Write(successJSONBytes)
    }

    // ? - What happens if an error fires after a redirect...?
    /*creator, e := c.Users.Get(reply.CreatedBy)
    if e == nil {
        e = creator.DecreasePostStats(c.WordCount(reply.Content), false)
        if e != nil {
            return c.InternalErrorJSQ(e, w, r, js)
        }
    } else if e != sql.ErrNoRows {
        return c.InternalErrorJSQ(e, w, r, js)
    }*/

    e := c.ModLogs.Create("delete", reply.ParentID, "reply", u.GetIP(), u.ID)
    if e != nil {
        return c.InternalErrorJSQ(e, w, r, js)
    }
    return nil
}

// TODO: Avoid uploading this again if the attachment already exists? They'll resolve to the same hash either way, but we could save on some IO / bandwidth here
// TODO: Enforce the max request limit on all of this topic's attachments
// TODO: Test this route
func AddAttachToReplySubmit(w http.ResponseWriter, r *http.Request, u *c.User, srid string) c.RouteError {
    reply, topic, lite, ferr := ReplyActPre(w, r, u, srid, true)
    if ferr != nil {
        return ferr
    }
    if !u.Perms.ViewTopic || !u.Perms.EditReply || !u.Perms.UploadFiles {
        return c.NoPermissionsJS(w, r, u)
    }
    if topic.IsClosed && !u.Perms.CloseTopic {
        return c.NoPermissionsJS(w, r, u)
    }

    // Handle the file attachments
    pathMap, rerr := uploadAttachment(w, r, u, topic.ParentID, "forums", reply.ID, "replies", strconv.Itoa(topic.ID))
    if rerr != nil {
        // TODO: This needs to be a JS error...
        return rerr
    }
    if len(pathMap) == 0 {
        return c.InternalErrorJS(errors.New("no paths for attachment add"), w, r)
    }

    skip, rerr := lite.Hooks.VhookSkippable("action_end_add_attach_to_reply", reply.ID, u)
    if skip || rerr != nil {
        return rerr
    }

    var elemStr string
    for path, aids := range pathMap {
        elemStr += "\"" + path + "\":\"" + aids + "\","
    }
    if len(elemStr) > 1 {
        elemStr = elemStr[:len(elemStr)-1]
    }

    w.Write([]byte(`{"success":1,"elems":{` + elemStr + `}}`))
    return nil
}

// TODO: Reduce the amount of duplication between this and RemoveAttachFromTopicSubmit
func RemoveAttachFromReplySubmit(w http.ResponseWriter, r *http.Request, u *c.User, srid string) c.RouteError {
    reply, topic, lite, ferr := ReplyActPre(w, r, u, srid, true)
    if ferr != nil {
        return ferr
    }
    if !u.Perms.ViewTopic || !u.Perms.EditReply {
        return c.NoPermissionsJS(w, r, u)
    }
    if topic.IsClosed && !u.Perms.CloseTopic {
        return c.NoPermissionsJS(w, r, u)
    }

    saids := strings.Split(r.PostFormValue("aids"), ",")
    if len(saids) == 0 {
        return c.LocalErrorJS("No aids provided", w, r)
    }
    for _, said := range saids {
        aid, err := strconv.Atoi(said)
        if err != nil {
            return c.LocalErrorJS(p.GetErrorPhrase("id_must_be_integer"), w, r)
        }
        rerr := deleteAttachment(w, r, u, aid, true)
        if rerr != nil {
            // TODO: This needs to be a JS error...
            return rerr
        }
    }

    skip, rerr := lite.Hooks.VhookSkippable("action_end_remove_attach_from_reply", reply.ID, u)
    if skip || rerr != nil {
        return rerr
    }

    w.Write(successJSONBytes)
    return nil
}

func ReplyActPre(w http.ResponseWriter, r *http.Request, u *c.User, srid string, js bool) (rep *c.Reply, t *c.Topic, l *c.HeaderLite, ferr c.RouteError) {
    rid, err := strconv.Atoi(srid)
    if err != nil {
        return rep, t, l, c.PreErrorJSQ("The provided Reply ID is not a valid number.", w, r, js)
    }
    rep, err = c.Rstore.Get(rid)
    if err == sql.ErrNoRows {
        return rep, t, l, c.PreErrorJSQ("The linked reply doesn't exist.", w, r, js)
    } else if err != nil {
        return rep, t, l, c.InternalErrorJSQ(err, w, r, js)
    }

    t, err = rep.Topic()
    if err == sql.ErrNoRows {
        return rep, t, l, c.PreErrorJSQ("The parent topic doesn't exist.", w, r, js)
    } else if err != nil {
        return rep, t, l, c.InternalErrorJSQ(err, w, r, js)
    }

    // TODO: Add hooks to make use of headerLite
    l, ferr = c.SimpleForumUserCheck(w, r, u, t.ParentID)
    return rep, t, l, ferr
}

func ReplyLikeSubmit(w http.ResponseWriter, r *http.Request, u *c.User, srid string) c.RouteError {
    js := r.PostFormValue("js") == "1"
    reply, _, lite, ferr := ReplyActPre(w, r, u, srid, js)
    if ferr != nil {
        return ferr
    }
    if !u.Perms.ViewTopic || !u.Perms.LikeItem {
        return c.NoPermissionsJSQ(w, r, u, js)
    }
    if reply.CreatedBy == u.ID {
        return c.LocalErrorJSQ("You can't like your own replies", w, r, u, js)
    }

    _, err := c.Users.Get(reply.CreatedBy)
    if err != nil && err != sql.ErrNoRows {
        return c.LocalErrorJSQ("The target user doesn't exist", w, r, u, js)
    } else if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }

    err = reply.Like(u.ID)
    if err == c.ErrAlreadyLiked {
        return c.LocalErrorJSQ("You've already liked this!", w, r, u, js)
    } else if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }

    // ! Be careful about leaking per-route permission state with user ptr
    alert := c.Alert{ActorID: u.ID, TargetUserID: reply.CreatedBy, Event: "like", ElementType: "post", ElementID: reply.ID, Actor: u}
    err = c.AddActivityAndNotifyTarget(alert)
    if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }

    skip, rerr := lite.Hooks.VhookSkippable("action_end_like_reply", reply.ID, u)
    if skip || rerr != nil {
        return rerr
    }
    return actionSuccess(w, r, "/topic/"+strconv.Itoa(reply.ParentID), js)
}

func ReplyUnlikeSubmit(w http.ResponseWriter, r *http.Request, u *c.User, srid string) c.RouteError {
    js := r.PostFormValue("js") == "1"
    reply, _, lite, ferr := ReplyActPre(w, r, u, srid, js)
    if ferr != nil {
        return ferr
    }
    if !u.Perms.ViewTopic || !u.Perms.LikeItem {
        return c.NoPermissionsJSQ(w, r, u, js)
    }

    _, err := c.Users.Get(reply.CreatedBy)
    if err != nil && err != sql.ErrNoRows {
        return c.LocalErrorJSQ("The target user doesn't exist", w, r, u, js)
    } else if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }
    err = reply.Unlike(u.ID)
    if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }

    // TODO: Better coupling between the two params queries
    aids, err := c.Activity.AidsByParams("like", reply.ID, "post")
    if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }
    for _, aid := range aids {
        c.DismissAlert(reply.CreatedBy, aid)
    }
    err = c.Activity.DeleteByParams("like", reply.ID, "post")
    if err != nil {
        return c.InternalErrorJSQ(err, w, r, js)
    }

    skip, rerr := lite.Hooks.VhookSkippable("action_end_unlike_reply", reply.ID, u)
    if skip || rerr != nil {
        return rerr
    }
    return actionSuccess(w, r, "/topic/"+strconv.Itoa(reply.ParentID), js)
}