gosora/common/settings.go

package common

import (
	"database/sql"
	"errors"
	"strconv"
	"strings"
	"sync/atomic"

	qgen "git.tuxpa.in/a/gosora/query_gen"
)

var SettingBox atomic.Value // An atomic value pointing to a SettingBox

// SettingMap is a map type specifically for holding the various settings admins set to toggle features on and off or to otherwise alter Gosora's behaviour from the Control Panel
type SettingMap map[string]interface{}

type SettingStore interface {
    ParseSetting(name, content, typ, constraint string) string
    BypassGet(name string) (*Setting, error)
    BypassGetAll(name string) ([]*Setting, error)
}

type OptionLabel struct {
    Label    string
    Value    int
    Selected bool
}

type Setting struct {
    Name       string
    Content    string
    Type       string
    Constraint string
}

type SettingStmts struct {
    getAll *sql.Stmt
    get    *sql.Stmt
    update *sql.Stmt
}

var settingStmts SettingStmts

func init() {
    SettingBox.Store(SettingMap(make(map[string]interface{})))
    DbInits.Add(func(acc *qgen.Accumulator) error {
        s := "settings"
        settingStmts = SettingStmts{
            getAll: acc.Select(s).Columns("name,content,type,constraints").Prepare(),
            get:    acc.Select(s).Columns("content,type,constraints").Where("name=?").Prepare(),
            update: acc.Update(s).Set("content=?").Where("name=?").Prepare(),
        }
        return acc.FirstError()
    })
}

func (s *Setting) Copy() (o *Setting) {
    o = &Setting{Name: ""}
    *o = *s
    return o
}

func LoadSettings() error {
    sBox := SettingMap(make(map[string]interface{}))
    settings, err := sBox.BypassGetAll()
    if err != nil {
        return err
    }

    for _, s := range settings {
        err = sBox.ParseSetting(s.Name, s.Content, s.Type, s.Constraint)
        if err != nil {
            return err
        }
    }

    SettingBox.Store(sBox)
    return nil
}

// TODO: Add better support for HTML attributes (html-attribute). E.g. Meta descriptions.
func (sBox SettingMap) ParseSetting(name, content, typ, constraint string) (err error) {
    ssBox := map[string]interface{}(sBox)
    switch typ {
    case "bool":
        ssBox[name] = (content == "1")
    case "int":
        ssBox[name], err = strconv.Atoi(content)
        if err != nil {
            return errors.New("You were supposed to enter an integer x.x")
        }
    case "int64":
        ssBox[name], err = strconv.ParseInt(content, 10, 64)
        if err != nil {
            return errors.New("You were supposed to enter an integer x.x")
        }
    case "list":
        cons := strings.Split(constraint, "-")
        if len(cons) < 2 {
            return errors.New("Invalid constraint! The second field wasn't set!")
        }

        con1, err := strconv.Atoi(cons[0])
        con2, err2 := strconv.Atoi(cons[1])
        if err != nil || err2 != nil {
            return errors.New("Invalid contraint! The constraint field wasn't an integer!")
        }

        val, err := strconv.Atoi(content)
        if err != nil {
            return errors.New("Only integers are allowed in this setting x.x")
        }

        if val < con1 || val > con2 {
            return errors.New("Only integers between a certain range are allowed in this setting")
        }
        ssBox[name] = val
    default:
        ssBox[name] = content
    }
    return nil
}

func (sBox SettingMap) BypassGet(name string) (*Setting, error) {
    s := &Setting{Name: name}
    err := settingStmts.get.QueryRow(name).Scan(&s.Content, &s.Type, &s.Constraint)
    return s, err
}

func (sBox SettingMap) BypassGetAll() (settingList []*Setting, err error) {
    rows, err := settingStmts.getAll.Query()
    if err != nil {
        return nil, err
    }
    defer rows.Close()

    for rows.Next() {
        s := &Setting{Name: ""}
        err := rows.Scan(&s.Name, &s.Content, &s.Type, &s.Constraint)
        if err != nil {
            return nil, err
        }
        settingList = append(settingList, s)
    }
    return settingList, rows.Err()
}

func (sBox SettingMap) Update(name, content string) RouteError {
    s, err := sBox.BypassGet(name)
    if err == ErrNoRows {
        return FromError(err)
    } else if err != nil {
        return SysError(err.Error())
    }

    // TODO: Why is this here and not in a common function?
    if s.Type == "bool" {
        if content == "on" || content == "1" {
            content = "1"
        } else {
            content = "0"
        }
    }

    err = sBox.ParseSetting(name, content, s.Type, s.Constraint)
    if err != nil {
        return FromError(err)
    }

    // TODO: Make this a method or function?
    _, err = settingStmts.update.Exec(content, name)
    if err != nil {
        return SysError(err.Error())
    }

    err = LoadSettings()
    if err != nil {
        return SysError(err.Error())
    }
    return nil
}