package config

import (
  "bytes"
  "errors"
  "fmt"
  "io/ioutil"
  "os"
  "path/filepath"
  "strconv"
  "strings"

  "github.com/BurntSushi/toml"
  "github.com/gdamore/tcell/v2"
)

type ConfigProfile struct {
  From                string
  Organization        string
}

type ConfigShortcuts struct {
  Refresh             int64
  Quit                int64

  FocusGroups         int64
  FocusArticles       int64
  FocusPreviews       int64

  NewArticle          int64
  ReplyToArticle      int64
}

type Config struct {
  ConfigFile          string `toml:"-"`

  ConnectionString    string

  CachePath           string // Deprecated, should be removed soon
  DatabaseCachePath   string
  ProgramCachePath    string

  Logfile             string

  Profile             ConfigProfile

  Shortcuts           map[string]string
  ShortcutsReference  string

  ArticlesListView    int8
}

func LoadConfig() (*Config, error) {
  configDir, exist := os.LookupEnv("XDG_CONFIG_HOME")
  if exist == false {
    configDir, exist = os.LookupEnv("HOME")
    if exist == false {
      return nil, errors.New("No XDG_CONFIG_HOME or HOME set!")
    }
    configDir = filepath.Join(configDir, ".config")
  }
  os.MkdirAll(configDir, 0755)

  configFile := filepath.Join(configDir, "superhighway84.toml")

  f, err := os.OpenFile(configFile, os.O_CREATE|os.O_RDWR, 0644)
  if err != nil {
    return nil, err
  }
  defer f.Close()

  configFileContent, err := ioutil.ReadAll(f)
  if err != nil {
    return nil, err
  }

  cfg := new(Config)
  cfg.Shortcuts = make(map[string]string)
  _, err = toml.Decode(string(configFileContent), &cfg)
  if err != nil {
    return nil, errors.New("The config could not be parsed, make sure it is valid TOML and you don't have double assignments.")
  }

  cfg.ConfigFile = configFile
  err = cfg.LoadDefaults()
  if err != nil {
    return nil, err
  }
  return cfg, nil
}

func (cfg *Config) LoadDefaults() (error) {

  shortcutDefaults := []struct{
    key           tcell.Key
    command       string
    keyAltText    string
  } {
    {tcell.KeyCtrlQ, "quit", "C-q"},
    {tcell.KeyCtrlR, "refresh", "C-r"},
    {tcell.KeyCtrlH, "focus-groups", "C-h"},
    {tcell.KeyCtrlL, "focus-articles", "C-l"},
    {tcell.KeyCtrlK, "focus-articles", "C-k"},
    {tcell.KeyCtrlJ, "focus-preview", "C-j"},
    {tcell.KeyCtrlA, "article-mark-all-read", "C-a"},

    {tcell.Key('n'), "article-new", ""},
    {tcell.Key('r'), "article-reply", ""},

    {tcell.Key('h'), "additional-key-left", ""},
    {tcell.Key('j'), "additional-key-down", ""},
    {tcell.Key('k'), "additional-key-up", ""},
    {tcell.Key('l'), "additional-key-right", ""},

    {tcell.Key('g'), "additional-key-home", ""},
    {tcell.Key('G'), "additional-key-end", ""},

    {tcell.Key('?'), "help", ""},
  }

  var sb strings.Builder
  for _, shortcut := range shortcutDefaults {
    keyText := string(shortcut.key)
    if shortcut.keyAltText != "" {
      keyText = shortcut.keyAltText
    }
    sb.WriteString(fmt.Sprintf("%s - %s\n", keyText, shortcut.command))
  }
  cfg.ShortcutsReference = sb.String()

  if len(cfg.Shortcuts) == 0 {
    for _, shortcut := range shortcutDefaults {
      cfg.Shortcuts[strconv.FormatInt(int64(shortcut.key), 10)] = shortcut.command
    }
  }

  return cfg.Persist()
}

func (cfg *Config) Persist() (error) {
  buf := new(bytes.Buffer)
  if err := toml.NewEncoder(buf).Encode(cfg); err != nil {
    return err
  }

  if err := ioutil.WriteFile(cfg.ConfigFile, buf.Bytes(), 0644); err != nil {
    return err
  }

  return nil
}

func (cfg *Config) WasSetup() (bool) {
  if cfg.DatabaseCachePath == "" ||
     cfg.ProgramCachePath == "" ||
     cfg.ConnectionString == "" ||
     cfg.Logfile == "" ||
     cfg.Profile.From == "" {
    return false
  }

  return true
}

func (cfg *Config) Setup() (error) {
  fmt.Printf("\nSUPERHIGHWAY84\n\nInitial Setup\n-------------\n\n")

  defaultConnectionString := "/orbitdb/bafyreifdpagppa7ve45odxuvudz5snbzcybwyfer777huckl4li4zbc5k4/superhighway84"
  if cfg.ConnectionString != "" {
    defaultConnectionString = cfg.ConnectionString
  }
  fmt.Printf("Database connection string [%s]: ", defaultConnectionString)
  fmt.Scanln(&cfg.ConnectionString)
  if strings.TrimSpace(cfg.ConnectionString) == "" {
    cfg.ConnectionString = defaultConnectionString
  }

  cacheDir, exist := os.LookupEnv("XDG_CACHE_HOME")
  if exist == false {
    cacheDir = filepath.Join(os.Getenv("HOME"), ".cache")
  }

  defaultDatabaseCachePath := filepath.Join(cacheDir, "superhighway84", "database")
  // Migration step from old CachePath to new DatabaseCachePath
  if cfg.CachePath != "" {
    defaultDatabaseCachePath = cfg.CachePath
  }
  fmt.Printf("Database cache path [%s]: ", defaultDatabaseCachePath)
  fmt.Scanln(&cfg.DatabaseCachePath)
  if strings.TrimSpace(cfg.DatabaseCachePath) == "" {
    cfg.DatabaseCachePath = defaultDatabaseCachePath
  }
  os.MkdirAll(filepath.Dir(cfg.DatabaseCachePath), 0755)

  defaultProgramCachePath := filepath.Join(cacheDir, "superhighway84", "program")
  // Migration step from old CachePath to new DatabaseCachePath
  if cfg.CachePath != "" {
    // If the previous CachePath was used, the folder already contains the
    // OrbitDB, hence we need to find a different place
    defaultProgramCachePath = filepath.Join(cacheDir, "superhighway84.program")
  }
  fmt.Printf("Program cache path [%s]: ", defaultProgramCachePath)
  fmt.Scanln(&cfg.ProgramCachePath)
  if strings.TrimSpace(cfg.ProgramCachePath) == "" {
    cfg.ProgramCachePath = defaultProgramCachePath
  }
  os.MkdirAll(filepath.Dir(cfg.ProgramCachePath), 0755)

  defaultLogfile := filepath.Join(cacheDir, "superhighway84.log")
  if cfg.Logfile != "" {
    defaultLogfile = cfg.Logfile
  }
  fmt.Printf("Logfile path [%s]: ", defaultLogfile)
  fmt.Scanln(&cfg.Logfile)
  if strings.TrimSpace(cfg.Logfile) == "" {
    cfg.Logfile = defaultLogfile
  }


  fmt.Printf("\nProfile information\n-------------------\n\n")

  defaultProfileFrom := fmt.Sprintf("%s@localhost", os.Getenv("USER"))
  if cfg.Profile.From != "" {
    defaultProfileFrom = cfg.Profile.From
  }
  fmt.Printf("From [%s]: ", defaultProfileFrom)
  fmt.Scanln(&cfg.Profile.From)
  if strings.TrimSpace(cfg.Profile.From) == "" {
    cfg.Profile.From = defaultProfileFrom
  }

  defaultProfileOrganization := ""
  if cfg.Profile.Organization != "" {
    defaultProfileOrganization = cfg.Profile.Organization
  }
  fmt.Printf("Organization [%s]: ", defaultProfileOrganization)
  fmt.Scanln(&cfg.Profile.Organization)

  return cfg.Persist()
}