9 files changed, 301 insertions, 57 deletions
diff --git a/auth/auth.go b/auth/auth.go
index c3b2cfd..e75d228 100644
--- a/auth/auth.go
+++ b/auth/auth.go
@@ -22,7 +22,6 @@ import (
   "os"
   "os/user"
   "fmt"
-  "github.com/zalando/go-keyring"
 )
 
 var serviceName string = "macli"
@@ -38,22 +37,20 @@ func init() {
   userName = currentUser.Username
 }
 
-func Login(secret string) {
-  err := keyring.Set(serviceName, userName, secret)
-  if err != nil {
-    fmt.Println("Error while writing access token to keychain", err)
-    os.Exit(1)
-  }
+// asks for all the details
+func Login() {
+  clientId := askClientId()
+  challenge := codeChallenge()
+  link := generateLink(clientId, challenge)
+  fmt.Println("Please open this link in the browser:")
+  fmt.Println(link)
 }
 
-func GetToken() string {
-  // get mal secret from keyring
-  secret, err := keyring.Get(serviceName, userName)
-  if err != nil {
-    fmt.Println("\x1b[31mError while reading access token from keychain:", err.Error(), "\x1b[0m")
-    fmt.Println("Run `macli login` first to authenticate with your MyAnimeList API Token")
-    os.Exit(1)
-  }
+func generateLink(clientId, challenge string) string {
+  return "https://myanimelist.net/v1/oauth2/authorize?response_type=code&client_id=" + clientId + "&code_challenge=" + challenge
+}
 
-  return secret
+func Logout() {
+  deleteClientId()
+  deleteToken()
 }
diff --git a/auth/challenge.go b/auth/challenge.go
new file mode 100644
index 0000000..60161ee
--- /dev/null
+++ b/auth/challenge.go
@@ -0,0 +1,35 @@
+/*
+macli - Unofficial CLI-Based MyAnimeList Client
+Copyright © 2022 Vidhu Kant Sharma <vidhukant@vidhukant.xyz>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package auth
+
+import (
+  "time"
+  "math/rand"
+)
+
+var letterRunes = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")
+
+func codeChallenge() string {
+    rand.Seed(time.Now().UnixNano())
+    b := make([]rune, 128)
+    for i := range b {
+        b[i] = letterRunes[rand.Intn(len(letterRunes))]
+    }
+    return string(b)
+}
diff --git a/auth/client.go b/auth/client.go
new file mode 100644
index 0000000..7268b8f
--- /dev/null
+++ b/auth/client.go
@@ -0,0 +1,67 @@
+/*
+macli - Unofficial CLI-Based MyAnimeList Client
+Copyright © 2022 Vidhu Kant Sharma <vidhukant@vidhukant.xyz>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package auth
+
+import (
+  "os"
+  "fmt"
+  "github.com/zalando/go-keyring"
+)
+
+var clientSuffix string = "-client-id"
+
+func getClientId() (string, error) {
+  return keyring.Get(serviceName + clientSuffix, userName)
+}
+
+func setClientId(clientId string) {
+  err := keyring.Set(serviceName + clientSuffix, userName, clientId)
+  if err != nil {
+    fmt.Println("Error while writing Client ID to keychain", err)
+    os.Exit(1)
+  }
+}
+
+func deleteClientId() {
+  err := keyring.Delete(serviceName + clientSuffix, userName)
+  // TODO: if secret doesnt exist dont show error
+  if err != nil {
+    fmt.Println(err)
+    os.Exit(1)
+  }
+}
+
+// if client id isn't in keyring
+// it will ask the user to enter/create one
+func askClientId() string {
+  clientId, err := getClientId()
+  if err != nil {
+    if err.Error() == "secret not found in keyring" {
+      fmt.Println("Looks like you don't have any Client ID saved.")
+      fmt.Println("If you don't have a MyAnimeList Client ID, please go to \x1b[34mhttps://myanimelist.net/apiconfig\x1b[0m and create one.")
+      fmt.Println("Remember to set the App Redirect Url to \x1b[33mhttp://localhost:8000\x1b[0m. Other details don't matter.")
+
+      // get clientId from user input
+      clientId = secretInput("Enter your Client ID: ", "Client ID Can't be blank")
+      setClientId(clientId)
+    }
+  }
+
+  return clientId
+}
diff --git a/auth/input.go b/auth/input.go
new file mode 100644
index 0000000..9f75fab
--- /dev/null
+++ b/auth/input.go
@@ -0,0 +1,57 @@
+/*
+macli - Unofficial CLI-Based MyAnimeList Client
+Copyright © 2022 Vidhu Kant Sharma <vidhukant@vidhukant.xyz>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package auth
+
+import (
+  "os"
+  "fmt"
+  "errors"
+  p "github.com/manifoldco/promptui"
+)
+
+// because importing macli/ui causes import cycle
+func secretInput(label, errMessage string) string {
+  validate := func(input string) error {
+    if input == "" {
+      return errors.New(errMessage)
+    }
+    return nil
+  }
+
+  template := &p.PromptTemplates {
+    Valid: "{{ . | cyan }}",
+    Invalid: "{{ . | cyan }}",
+    Success: "{{ . | blue }}",
+  }
+
+  prompt := p.Prompt {
+    Label: label,
+    Templates: template,
+    Validate: validate,
+    Mask: '*',
+  }
+
+  res, err := prompt.Run()
+  if err != nil {
+    fmt.Println("Failed to run secret input prompt.", err.Error())
+    os.Exit(1)
+  }
+
+  return res
+}
diff --git a/auth/server.go b/auth/server.go
new file mode 100644
index 0000000..eef95bb
--- /dev/null
+++ b/auth/server.go
@@ -0,0 +1,35 @@
+/*
+macli - Unofficial CLI-Based MyAnimeList Client
+Copyright © 2022 Vidhu Kant Sharma <vidhukant@vidhukant.xyz>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package auth
+
+// import (
+//   "net/http"
+//   "os"
+//   "fmt"
+// )
+//
+// func listen() {
+//   http.HandleFunc("/", getRoot)
+//
+//   err := http.ListenAndServe(":8000", nil)
+//   if err != nil {
+//     fmt.Println("There was an error initialising the server", err.Error())
+//     os.Exit(1)
+//   }
+// }
diff --git a/auth/token.go b/auth/token.go
new file mode 100644
index 0000000..5997025
--- /dev/null
+++ b/auth/token.go
@@ -0,0 +1,53 @@
+/*
+macli - Unofficial CLI-Based MyAnimeList Client
+Copyright © 2022 Vidhu Kant Sharma <vidhukant@vidhukant.xyz>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package auth
+
+import (
+  "os"
+  "fmt"
+  "github.com/zalando/go-keyring"
+)
+
+func GetToken() string {
+  secret, err := keyring.Get(serviceName, userName)
+  if err != nil {
+    fmt.Println("\x1b[31mError while reading access token from keychain:", err.Error(), "\x1b[0m")
+    fmt.Println("Run `macli login` first to authenticate with your MyAnimeList API Token")
+    os.Exit(1)
+  }
+
+  return secret
+}
+
+func setToken(secret string) {
+  err := keyring.Set(serviceName, userName, secret)
+  if err != nil {
+    fmt.Println("Error while writing access token to keychain", err)
+    os.Exit(1)
+  }
+}
+
+func deleteToken() {
+  err := keyring.Delete(serviceName, userName)
+  // TODO: if secret doesnt exist dont show error
+  if err != nil {
+    fmt.Println(err)
+    os.Exit(1)
+  }
+}
diff --git a/cmd/login.go b/cmd/login.go
index bcecc3f..74a6947 100644
--- a/cmd/login.go
+++ b/cmd/login.go
@@ -20,24 +20,15 @@ package cmd
 
 import (
 	"github.com/spf13/cobra"
-	"github.com/MikunoNaka/macli/ui"
 	"github.com/MikunoNaka/macli/auth"
 )
 
 var loginCmd = &cobra.Command {
 	Use:   "login",
 	Short: "Login with your MyAnimeList client secret",
-	Long: `
-Currently, macli doesn't support logging in.
-You need to manually generate an access token/client secret to authorise
-macli with your MyAnimeList account.
-
-An easy way to generate a token is to use my python script:
-https://github.com/MikunoNaka/mal-authtoken-generator
-`,
+	Long: ``,
 	Run: func(cmd *cobra.Command, args []string) {
-		secret := ui.PasswordInput("Enter your client secret: ", "Client secret can't be empty")
-		auth.Login(secret)
+		auth.Login()
 	},
 }
 
diff --git a/cmd/logout.go b/cmd/logout.go
new file mode 100644
index 0000000..403f6aa
--- /dev/null
+++ b/cmd/logout.go
@@ -0,0 +1,39 @@
+/*
+macli - Unofficial CLI-Based MyAnimeList Client
+Copyright © 2022 Vidhu Kant Sharma <vidhukant@vidhukant.xyz>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package cmd
+
+import (
+	"github.com/spf13/cobra"
+	"github.com/MikunoNaka/macli/auth"
+)
+
+var logoutCmd = &cobra.Command {
+	Use:   "logout",
+	Short: "Logout from macli",
+	Long: `Logout from macli
+This will delete the Auth Token and Client ID from system's keyring.
+`,
+	Run: func(cmd *cobra.Command, args []string) {
+		auth.Logout()
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(logoutCmd)
+}
diff --git a/ui/input.go b/ui/input.go
index a334943..d26d2f3 100644
--- a/ui/input.go
+++ b/ui/input.go
@@ -51,33 +51,3 @@ func TextInput(label, errMessage string) string {
 
   return res
 }
-
-func PasswordInput(label, errMessage string) string {
-  validate := func(input string) error {
-    if input == "" {
-      return errors.New(errMessage)
-    }
-    return nil
-  }
-
-  template := &p.PromptTemplates {
-    Valid: "{{ . | cyan }}",
-    Invalid: "{{ . | cyan }}",
-    Success: "{{ . | blue }}",
-  }
-
-  prompt := p.Prompt {
-    Label: label,
-    Templates: template,
-    Validate: validate,
-    Mask: '*',
-  }
-
-  res, err := prompt.Run()
-  if err != nil {
-    fmt.Println("Failed to run input prompt.", err.Error())
-    os.Exit(1)
-  }
-
-  return res
-}