package main

import (
	"database/sql"
	"encoding/json"
	"log"
	"sync"

	"./query_gen/lib"
)

// TODO: Refactor the perms system

var permUpdateMutex sync.Mutex
var BlankPerms Perms
var BlankForumPerms ForumPerms
var GuestPerms Perms
var ReadForumPerms ForumPerms
var ReadReplyForumPerms ForumPerms
var ReadWriteForumPerms ForumPerms
var AllPerms Perms
var AllForumPerms ForumPerms
var AllPluginPerms = make(map[string]bool)

// ? - Can we avoid duplicating the items in this list in a bunch of places?

var LocalPermList = []string{
	"ViewTopic",
	"LikeItem",
	"CreateTopic",
	"EditTopic",
	"DeleteTopic",
	"CreateReply",
	"EditReply",
	"DeleteReply",
	"PinTopic",
	"CloseTopic",
}

// ? - Can we avoid duplicating the items in this list in a bunch of places?
var GlobalPermList = []string{
	"BanUsers",
	"ActivateUsers",
	"EditUser",
	"EditUserEmail",
	"EditUserPassword",
	"EditUserGroup",
	"EditUserGroupSuperMod",
	"EditUserGroupAdmin",
	"EditGroup",
	"EditGroupLocalPerms",
	"EditGroupGlobalPerms",
	"EditGroupSuperMod",
	"EditGroupAdmin",
	"ManageForums",
	"EditSettings",
	"ManageThemes",
	"ManagePlugins",
	"ViewAdminLogs",
	"ViewIPs",
	"UploadFiles",
}

// Permission Structure: ActionComponent[Subcomponent]Flag
type Perms struct {
	// Global Permissions
	BanUsers              bool
	ActivateUsers         bool
	EditUser              bool
	EditUserEmail         bool
	EditUserPassword      bool
	EditUserGroup         bool
	EditUserGroupSuperMod bool
	EditUserGroupAdmin    bool
	EditGroup             bool
	EditGroupLocalPerms   bool
	EditGroupGlobalPerms  bool
	EditGroupSuperMod     bool
	EditGroupAdmin        bool
	ManageForums          bool // This could be local, albeit limited for per-forum managers?
	EditSettings          bool
	ManageThemes          bool
	ManagePlugins         bool
	ViewAdminLogs         bool
	ViewIPs               bool

	// Global non-staff permissions
	UploadFiles bool
	// TODO: Add a permission for enabling avatars

	// Forum permissions
	ViewTopic   bool
	LikeItem    bool
	CreateTopic bool
	EditTopic   bool
	DeleteTopic bool
	CreateReply bool
	//CreateReplyToOwn bool
	EditReply bool
	//EditOwnReply bool
	DeleteReply bool
	PinTopic    bool
	CloseTopic  bool
	//CloseOwnTopic bool

	//ExtData map[string]bool
}

/* Inherit from group permissions for ones we don't have */
type ForumPerms struct {
	ViewTopic   bool
	LikeItem    bool
	CreateTopic bool
	EditTopic   bool
	DeleteTopic bool
	CreateReply bool
	//CreateReplyToOwn bool
	EditReply bool
	//EditOwnReply bool
	DeleteReply bool
	PinTopic    bool
	CloseTopic  bool
	//CloseOwnTopic bool

	Overrides bool
	ExtData   map[string]bool
}

func init() {
	BlankPerms = Perms{
	//ExtData: make(map[string]bool),
	}

	BlankForumPerms = ForumPerms{
		ExtData: make(map[string]bool),
	}

	GuestPerms = Perms{
		ViewTopic: true,
		//ExtData: make(map[string]bool),
	}

	AllPerms = Perms{
		BanUsers:              true,
		ActivateUsers:         true,
		EditUser:              true,
		EditUserEmail:         true,
		EditUserPassword:      true,
		EditUserGroup:         true,
		EditUserGroupSuperMod: true,
		EditUserGroupAdmin:    true,
		EditGroup:             true,
		EditGroupLocalPerms:   true,
		EditGroupGlobalPerms:  true,
		EditGroupSuperMod:     true,
		EditGroupAdmin:        true,
		ManageForums:          true,
		EditSettings:          true,
		ManageThemes:          true,
		ManagePlugins:         true,
		ViewAdminLogs:         true,
		ViewIPs:               true,

		UploadFiles: true,

		ViewTopic:   true,
		LikeItem:    true,
		CreateTopic: true,
		EditTopic:   true,
		DeleteTopic: true,
		CreateReply: true,
		EditReply:   true,
		DeleteReply: true,
		PinTopic:    true,
		CloseTopic:  true,

		//ExtData: make(map[string]bool),
	}

	AllForumPerms = ForumPerms{
		ViewTopic:   true,
		LikeItem:    true,
		CreateTopic: true,
		EditTopic:   true,
		DeleteTopic: true,
		CreateReply: true,
		EditReply:   true,
		DeleteReply: true,
		PinTopic:    true,
		CloseTopic:  true,

		Overrides: true,
		ExtData:   make(map[string]bool),
	}

	ReadWriteForumPerms = ForumPerms{
		ViewTopic:   true,
		LikeItem:    true,
		CreateTopic: true,
		CreateReply: true,
		Overrides:   true,
		ExtData:     make(map[string]bool),
	}

	ReadReplyForumPerms = ForumPerms{
		ViewTopic:   true,
		LikeItem:    true,
		CreateReply: true,
		Overrides:   true,
		ExtData:     make(map[string]bool),
	}

	ReadForumPerms = ForumPerms{
		ViewTopic: true,
		Overrides: true,
		ExtData:   make(map[string]bool),
	}

	guestUser.Perms = GuestPerms

	if dev.DebugMode {
		log.Printf("Guest Perms: %+v\n", GuestPerms)
		log.Printf("All Perms: %+v\n", AllPerms)
	}
}

func presetToPermmap(preset string) (out map[string]ForumPerms) {
	out = make(map[string]ForumPerms)
	switch preset {
	case "all":
		out["guests"] = ReadForumPerms
		out["members"] = ReadWriteForumPerms
		out["staff"] = AllForumPerms
		out["admins"] = AllForumPerms
	case "announce":
		out["guests"] = ReadForumPerms
		out["members"] = ReadReplyForumPerms
		out["staff"] = AllForumPerms
		out["admins"] = AllForumPerms
	case "members":
		out["guests"] = BlankForumPerms
		out["members"] = ReadWriteForumPerms
		out["staff"] = AllForumPerms
		out["admins"] = AllForumPerms
	case "staff":
		out["guests"] = BlankForumPerms
		out["members"] = BlankForumPerms
		out["staff"] = ReadWriteForumPerms
		out["admins"] = AllForumPerms
	case "admins":
		out["guests"] = BlankForumPerms
		out["members"] = BlankForumPerms
		out["staff"] = BlankForumPerms
		out["admins"] = AllForumPerms
	case "archive":
		out["guests"] = ReadForumPerms
		out["members"] = ReadForumPerms
		out["staff"] = ReadForumPerms
		out["admins"] = ReadForumPerms //CurateForumPerms. Delete / Edit but no create?
	default:
		out["guests"] = BlankForumPerms
		out["members"] = BlankForumPerms
		out["staff"] = BlankForumPerms
		out["admins"] = BlankForumPerms
	}
	return out
}

func permmapToQuery(permmap map[string]ForumPerms, fid int) error {
	tx, err := db.Begin()
	if err != nil {
		return err
	}
	defer tx.Rollback()

	deleteForumPermsByForumTx, err := qgen.Builder.SimpleDeleteTx(tx, "forums_permissions", "fid = ?")
	if err != nil {
		return err
	}

	_, err = deleteForumPermsByForumTx.Exec(fid)
	if err != nil {
		return err
	}

	perms, err := json.Marshal(permmap["admins"])
	if err != nil {
		return err
	}

	addForumPermsToForumAdminsTx, err := qgen.Builder.SimpleInsertSelectTx(tx,
		qgen.DB_Insert{"forums_permissions", "gid, fid, preset, permissions", ""},
		qgen.DB_Select{"users_groups", "gid, ? AS fid, ? AS preset, ? AS permissions", "is_admin = 1", "", ""},
	)
	if err != nil {
		return err
	}

	_, err = addForumPermsToForumAdminsTx.Exec(fid, "", perms)
	if err != nil {
		return err
	}

	perms, err = json.Marshal(permmap["staff"])
	if err != nil {
		return err
	}

	addForumPermsToForumStaffTx, err := qgen.Builder.SimpleInsertSelectTx(tx,
		qgen.DB_Insert{"forums_permissions", "gid, fid, preset, permissions", ""},
		qgen.DB_Select{"users_groups", "gid, ? AS fid, ? AS preset, ? AS permissions", "is_admin = 0 AND is_mod = 1", "", ""},
	)
	if err != nil {
		return err
	}
	_, err = addForumPermsToForumStaffTx.Exec(fid, "", perms)
	if err != nil {
		return err
	}

	perms, err = json.Marshal(permmap["members"])
	if err != nil {
		return err
	}

	addForumPermsToForumMembersTx, err := qgen.Builder.SimpleInsertSelectTx(tx,
		qgen.DB_Insert{"forums_permissions", "gid, fid, preset, permissions", ""},
		qgen.DB_Select{"users_groups", "gid, ? AS fid, ? AS preset, ? AS permissions", "is_admin = 0 AND is_mod = 0 AND is_banned = 0", "", ""},
	)
	if err != nil {
		return err
	}
	_, err = addForumPermsToForumMembersTx.Exec(fid, "", perms)
	if err != nil {
		return err
	}

	// 6 is the ID of the Not Loggedin Group
	// TODO: Use a shared variable rather than a literal for the group ID
	err = replaceForumPermsForGroupTx(tx, 6, map[int]string{fid: ""}, map[int]ForumPerms{fid: permmap["guests"]})
	if err != nil {
		return err
	}

	err = tx.Commit()
	if err != nil {
		return err
	}

	permUpdateMutex.Lock()
	defer permUpdateMutex.Unlock()
	return rebuildForumPermissions(fid)
}

func replaceForumPermsForGroup(gid int, presetSet map[int]string, permSets map[int]ForumPerms) error {
	tx, err := db.Begin()
	if err != nil {
		return err
	}
	defer tx.Rollback()
	err = replaceForumPermsForGroupTx(tx, gid, presetSet, permSets)
	if err != nil {
		return err
	}
	return tx.Commit()
}

func replaceForumPermsForGroupTx(tx *sql.Tx, gid int, presetSets map[int]string, permSets map[int]ForumPerms) error {
	deleteForumPermsForGroupTx, err := qgen.Builder.SimpleDeleteTx(tx, "forums_permissions", "gid = ? AND fid = ?")
	if err != nil {
		return err
	}

	addForumPermsToGroupTx, err := qgen.Builder.SimpleInsertTx(tx, "forums_permissions", "gid, fid, preset, permissions", "?,?,?,?")
	if err != nil {
		return err
	}
	for fid, permSet := range permSets {
		permstr, err := json.Marshal(permSet)
		if err != nil {
			return err
		}
		_, err = deleteForumPermsForGroupTx.Exec(gid, fid)
		if err != nil {
			return err
		}
		_, err = addForumPermsToGroupTx.Exec(gid, fid, presetSets[fid], string(permstr))
		if err != nil {
			return err
		}
	}

	return nil
}

// TODO: Need a more thread-safe way of doing this. Possibly with sync.Map?
func rebuildForumPermissions(fid int) error {
	if dev.DebugMode {
		log.Print("Loading the forum permissions")
	}
	fids, err := fstore.GetAllIDs()
	if err != nil {
		return err
	}

	rows, err := db.Query("select gid, permissions from forums_permissions where fid = ? order by gid asc", fid)
	if err != nil {
		return err
	}
	defer rows.Close()

	if dev.DebugMode {
		log.Print("Updating the forum permissions")
	}
	for rows.Next() {
		var gid int
		var perms []byte
		var pperms ForumPerms
		err := rows.Scan(&gid, &perms)
		if err != nil {
			return err
		}
		err = json.Unmarshal(perms, &pperms)
		if err != nil {
			return err
		}
		pperms.ExtData = make(map[string]bool)
		pperms.Overrides = true
		_, ok := forumPerms[gid]
		if !ok {
			forumPerms[gid] = make(map[int]ForumPerms)
		}
		forumPerms[gid][fid] = pperms
	}

	return cascadePermSetToGroups(forumPerms, fids)
}

func buildForumPermissions() error {
	fids, err := fstore.GetAllIDs()
	if err != nil {
		return err
	}
	if dev.SuperDebug {
		log.Print("fids: ", fids)
	}

	rows, err := getForumsPermissionsStmt.Query()
	if err != nil {
		return err
	}
	defer rows.Close()

	if dev.DebugMode {
		log.Print("Adding the forum permissions")
		if dev.SuperDebug {
			log.Print("forumPerms[gid][fid]")
		}
	}

	// Temporarily store the forum perms in a map before transferring it to a much faster and thread-safe slice
	forumPerms = make(map[int]map[int]ForumPerms)
	for rows.Next() {
		var gid, fid int
		var perms []byte
		var pperms ForumPerms
		err = rows.Scan(&gid, &fid, &perms)
		if err != nil {
			return err
		}

		if dev.SuperDebug {
			log.Print("perms: ", string(perms))
		}
		err = json.Unmarshal(perms, &pperms)
		if err != nil {
			return err
		}
		pperms.ExtData = make(map[string]bool)
		pperms.Overrides = true
		_, ok := forumPerms[gid]
		if !ok {
			forumPerms[gid] = make(map[int]ForumPerms)
		}

		if dev.SuperDebug {
			log.Print("gid: ", gid)
			log.Print("fid: ", fid)
			log.Printf("perms: %+v;", pperms)
		}
		forumPerms[gid][fid] = pperms
	}

	return cascadePermSetToGroups(forumPerms, fids)
}

func cascadePermSetToGroups(forumPerms map[int]map[int]ForumPerms, fids []int) error {
	groups, err := gstore.GetAll()
	if err != nil {
		return err
	}

	for _, group := range groups {
		if dev.DebugMode {
			log.Printf("Updating the forum permissions for Group #%d", group.ID)
		}
		group.Forums = []ForumPerms{BlankForumPerms}
		group.CanSee = []int{}
		cascadePermSetToGroup(forumPerms, group, fids)

		if dev.SuperDebug {
			log.Printf("group.CanSee %+v\n", group.CanSee)
			log.Printf("group.Forums %+v\n", group.Forums)
			log.Print("len(group.CanSee): ", len(group.CanSee))
			log.Print("len(group.Forums): ", len(group.Forums)) // This counts blank aka 0
		}
	}
	return nil
}

func cascadePermSetToGroup(forumPerms map[int]map[int]ForumPerms, group *Group, fids []int) {
	for _, fid := range fids {
		if dev.SuperDebug {
			log.Printf("Forum #%+v\n", fid)
		}
		forumPerm, ok := forumPerms[group.ID][fid]
		if ok {
			// Override group perms
			//log.Print("Overriding permissions for forum #" + strconv.Itoa(fid))
			group.Forums = append(group.Forums, forumPerm)
		} else {
			// Inherit from Group
			//log.Print("Inheriting from default for forum #" + strconv.Itoa(fid))
			forumPerm = BlankForumPerms
			group.Forums = append(group.Forums, forumPerm)
		}
		if forumPerm.Overrides {
			if forumPerm.ViewTopic {
				group.CanSee = append(group.CanSee, fid)
			}
		} else if group.Perms.ViewTopic {
			group.CanSee = append(group.CanSee, fid)
		}

		if dev.SuperDebug {
			log.Print("group.ID: ", group.ID)
			log.Printf("forumPerm: %+v\n", forumPerm)
			log.Print("group.CanSee: ", group.CanSee)
		}
	}
}

func forumPermsToGroupForumPreset(fperms ForumPerms) string {
	if !fperms.Overrides {
		return "default"
	}
	if !fperms.ViewTopic {
		return "no_access"
	}
	var canPost = (fperms.LikeItem && fperms.CreateTopic && fperms.CreateReply)
	var canModerate = (canPost && fperms.EditTopic && fperms.DeleteTopic && fperms.EditReply && fperms.DeleteReply && fperms.PinTopic && fperms.CloseTopic)
	if canModerate {
		return "can_moderate"
	}
	if fperms.EditTopic || fperms.DeleteTopic || fperms.EditReply || fperms.DeleteReply || fperms.PinTopic || fperms.CloseTopic {
		if !canPost {
			return "custom"
		}
		return "quasi_mod"
	}

	if canPost {
		return "can_post"
	}
	if fperms.ViewTopic && !fperms.LikeItem && !fperms.CreateTopic && !fperms.CreateReply {
		return "read_only"
	}
	return "custom"
}

func groupForumPresetToForumPerms(preset string) (fperms ForumPerms, changed bool) {
	switch preset {
	case "read_only":
		return ReadForumPerms, true
	case "can_post":
		return ReadWriteForumPerms, true
	case "can_moderate":
		return AllForumPerms, true
	case "no_access":
		return ForumPerms{Overrides: true, ExtData: make(map[string]bool)}, true
	case "default":
		return BlankForumPerms, true
		//case "custom": return fperms, false
	}
	return fperms, false
}

func stripInvalidGroupForumPreset(preset string) string {
	switch preset {
	case "read_only", "can_post", "can_moderate", "no_access", "default", "custom":
		return preset
	}
	return ""
}

func stripInvalidPreset(preset string) string {
	switch preset {
	case "all", "announce", "members", "staff", "admins", "archive", "custom":
		return preset
	default:
		return ""
	}
}

// TODO: Move this into the phrase system?
func presetToLang(preset string) string {
	switch preset {
	case "all":
		return "Public"
	case "announce":
		return "Announcements"
	case "members":
		return "Member Only"
	case "staff":
		return "Staff Only"
	case "admins":
		return "Admin Only"
	case "archive":
		return "Archive"
	case "custom":
		return "Custom"
	default:
		return ""
	}
}

// TODO: Is this racey?
func rebuildGroupPermissions(gid int) error {
	var permstr []byte
	log.Print("Reloading a group")
	err := db.QueryRow("select permissions from users_groups where gid = ?", gid).Scan(&permstr)
	if err != nil {
		return err
	}

	tmpPerms := Perms{
	//ExtData: make(map[string]bool),
	}
	err = json.Unmarshal(permstr, &tmpPerms)
	if err != nil {
		return err
	}

	group, err := gstore.Get(gid)
	if err != nil {
		return err
	}
	group.Perms = tmpPerms
	return nil
}

func overridePerms(perms *Perms, status bool) {
	if status {
		*perms = AllPerms
	} else {
		*perms = BlankPerms
	}
}

// TODO: We need a better way of overriding forum perms rather than setting them one by one
func overrideForumPerms(perms *Perms, status bool) {
	perms.ViewTopic = status
	perms.LikeItem = status
	perms.CreateTopic = status
	perms.EditTopic = status
	perms.DeleteTopic = status
	perms.CreateReply = status
	perms.EditReply = status
	perms.DeleteReply = status
	perms.PinTopic = status
	perms.CloseTopic = status
}

func registerPluginPerm(name string) {
	AllPluginPerms[name] = true
}

func deregisterPluginPerm(name string) {
	delete(AllPluginPerms, name)
}