From 1201abcffadab69d5a16844e968f8d50a53bdb35 Mon Sep 17 00:00:00 2001
From: Dietmar Maurer <dietmar@proxmox.com>
Date: Sat, 30 Nov 2019 12:57:02 +0100
Subject: [PATCH] src/cli/command.rs: implement help

---
 src/bin/completion.rs |  11 +----
 src/cli/command.rs    | 100 ++++++++++++++++++++++++++++++++++--------
 src/cli/completion.rs |  11 ++---
 3 files changed, 89 insertions(+), 33 deletions(-)

diff --git a/src/bin/completion.rs b/src/bin/completion.rs
index 754c674e..62fb0e5e 100644
--- a/src/bin/completion.rs
+++ b/src/bin/completion.rs
@@ -37,7 +37,6 @@ fn command_map() -> CliCommandMap {
     cmd_def
 }
 
-
 fn main() -> Result<(), Error> {
 
     let def = CommandLineInterface::Nested(command_map());
@@ -58,14 +57,8 @@ fn main() -> Result<(), Error> {
         let args = shellword_split(&line)?;
 
         let def = helper.cmd_def();
-        let _ = match def {
-            CommandLineInterface::Simple(ref cli_cmd) => {
-                handle_simple_command(def, "", &cli_cmd, args)
-            }
-            CommandLineInterface::Nested(ref map) => {
-                handle_nested_command(def, "", &map, args)
-            }
-        };
+
+        handle_command(def, "", args);
     }
 
     Ok(())
diff --git a/src/cli/command.rs b/src/cli/command.rs
index ba4704be..cea760cc 100644
--- a/src/cli/command.rs
+++ b/src/cli/command.rs
@@ -1,7 +1,10 @@
 use failure::*;
 use serde_json::Value;
 use std::collections::HashMap;
+use std::sync::Arc;
+use std::cell::RefCell;
 
+use proxmox::api::*;
 use proxmox::api::format::*;
 use proxmox::api::schema::*;
 use proxmox::api::{ApiHandler, ApiMethod};
@@ -321,16 +324,88 @@ pub fn print_bash_completion(def: &CommandLineInterface) {
     }
 }
 
-const VERBOSE_HELP_SCHEMA: Schema = BooleanSchema::new("Verbose help.").schema();
-const COMMAND_HELP: ObjectSchema = ObjectSchema::new(
-    "Get help about specified command.",
-    &[ ("verbose", true, &VERBOSE_HELP_SCHEMA) ]
+const API_METHOD_COMMAND_HELP: ApiMethod = ApiMethod::new(
+    &ApiHandler::Sync(&help_command),
+    &ObjectSchema::new(
+        "Get help about specified command.",
+        &[
+            ( "command",
+               true,
+               &StringSchema::new("Command name.").schema()
+            ),
+            ( "verbose",
+               true,
+               &BooleanSchema::new("Verbose help.").schema()
+            ),
+        ],
+    )
 );
 
-const API_METHOD_COMMAND_HELP: ApiMethod = ApiMethod::new_dummy(&COMMAND_HELP);
+std::thread_local! {
+    static HELP_CONTEXT: RefCell<Option<Arc<CommandLineInterface>>> = RefCell::new(None);
+}
+
+fn help_command(
+    param: Value,
+    _info: &ApiMethod,
+    _rpcenv: &mut dyn RpcEnvironment,
+) -> Result<Value, Error> {
+
+
+    let command = param["command"].as_str();
+    let verbose = param["verbose"].as_bool();
+
+    HELP_CONTEXT.with(|ctx| {
+        match &*ctx.borrow() {
+            Some(def) => {
+                let mut args = Vec::new();
+                // TODO: Handle multilevel sub commands
+                if let Some(command) = command {
+                    args.push(command.to_string());
+                }
+
+                print_help(def, String::from(""), &args, verbose);
+            }
+            None => {
+                eprintln!("Sorry, help context not set - internal error.");
+            }
+        }
+    });
+
+    Ok(Value::Null)
+}
+
+pub fn set_help_context(def: Option<Arc<CommandLineInterface>>) {
+    HELP_CONTEXT.with(|ctx| { *ctx.borrow_mut() = def; });
+}
 
 pub fn help_command_def() ->  CliCommand {
     CliCommand::new(&API_METHOD_COMMAND_HELP)
+        .arg_param(&["command"])
+}
+
+pub fn handle_command(
+    def: Arc<CommandLineInterface>,
+    prefix: &str,
+    args: Vec<String>,
+) {
+
+    set_help_context(Some(def.clone()));
+
+    match &*def {
+        CommandLineInterface::Simple(ref cli_cmd) => {
+            if let Err(_) = handle_simple_command(&def, &prefix, &cli_cmd, args) {
+                std::process::exit(-1);
+            }
+        }
+        CommandLineInterface::Nested(ref map) => {
+            if let Err(_) = handle_nested_command(&def, &prefix, &map, args) {
+                std::process::exit(-1);
+            }
+        }
+    };
+
+    set_help_context(None);
 }
 
 pub fn run_cli_command(def: CommandLineInterface) {
@@ -341,8 +416,6 @@ pub fn run_cli_command(def: CommandLineInterface) {
             CommandLineInterface::Nested(map.insert("help", help_command_def().into())),
     };
 
-    let top_def = &def; // we pass this to the help function ...
-
     let mut args = std::env::args();
 
     let prefix = args.next().unwrap();
@@ -370,16 +443,5 @@ pub fn run_cli_command(def: CommandLineInterface) {
         }
     }
 
-    match def {
-        CommandLineInterface::Simple(ref cli_cmd) => {
-            if let Err(_) = handle_simple_command(top_def, &prefix, &cli_cmd, args) {
-                std::process::exit(-1);
-            }
-        }
-        CommandLineInterface::Nested(ref map) => {
-            if let Err(_) = handle_nested_command(top_def, &prefix, &map, args) {
-                std::process::exit(-1);
-            }
-        }
-    };
+    handle_command(Arc::new(def), &prefix, args);
 }
diff --git a/src/cli/completion.rs b/src/cli/completion.rs
index ede5547f..d362a086 100644
--- a/src/cli/completion.rs
+++ b/src/cli/completion.rs
@@ -1,4 +1,5 @@
 use failure::*;
+use std::sync::Arc;
 
 use rustyline::completion::*;
 
@@ -196,17 +197,17 @@ pub fn get_completions(
 }
 
 pub struct CliHelper {
-    cmd_def:  CommandLineInterface,
+    cmd_def: Arc<CommandLineInterface>,
 }
 
 impl CliHelper {
 
     pub fn new(cmd_def: CommandLineInterface) -> Self {
-        Self { cmd_def }
+        Self { cmd_def: Arc::new(cmd_def) }
     }
 
-    pub fn cmd_def(&self) -> &CommandLineInterface {
-        &self.cmd_def
+    pub fn cmd_def(&self) -> Arc<CommandLineInterface> {
+        self.cmd_def.clone()
     }
 }
 
@@ -222,7 +223,7 @@ impl rustyline::completion::Completer for CliHelper {
 
         let line = &line[..pos];
 
-        let (start, completions) = super::get_completions(&self.cmd_def, line, false);
+        let (start, completions) = super::get_completions(&*self.cmd_def, line, false);
 
         return Ok((start, completions));
     }