1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142

use std::{error::Error};
use clap::{Parser, Arg, Command};
use inquire::{Text, Confirm, Select};

pub trait InteractiveParse
where Self: Sized
{
    fn interactive_parse() -> Result<Self, Box<dyn Error>>;
}

fn parse_required_arg(arg: &Arg) -> Result<Vec<String>, Box<dyn Error>> {
    let mut output_args = vec![];
    let id = arg.get_id();
    match arg.is_positional() {
        // Arg is positional
        true => { },
        // Arg uses flag
        false => { output_args.push(format!("--{}", id)); },
    }
    let mut text = Text::new(arg.get_id().as_str());

    // Add a help string
    let help_string;
    if let Some(help) = arg.get_help() {
        help_string = help.to_string();
        text = text.with_help_message(help_string.as_str());
    }

    output_args.push(text.prompt()?);
    Ok(output_args)
}

fn parse_optional_arg(arg: &Arg) -> Result<Vec<String>, Box<dyn Error>> {
    match Confirm::new("Add optional value?")
    .with_help_message(arg.get_id().as_str())
    .prompt()? 
    {
        true => { parse_required_arg(arg) },
        false => Ok(vec![]),
    }
}

fn parse_vec_arg(arg: &Arg) -> Result<Vec<String>, Box<dyn Error>> {
    let mut new_args = parse_optional_arg(arg)?;
    let mut total_args = vec![];
    while new_args.len() != 0 {
        total_args.extend(new_args);
        new_args = parse_optional_arg(arg)?;
    }
    if let Some(value_delimiter) = arg.get_value_delimiter() {
        total_args.join(value_delimiter.to_string().as_str());
    }
    Ok(total_args)
}

fn parse_arg(arg: &Arg) -> Result<Vec<String>, Box<dyn Error>> {
    match arg.get_num_args() {
        // arg is a vec
        Some(_) => {
            parse_vec_arg(arg)
        },
        None => {
            match arg.is_required_set() {
                true => parse_required_arg(arg),
                false => parse_optional_arg(arg),
            }
        },
    }

}

fn get_args<'a>(command: impl Iterator<Item = &'a Arg>) -> Result<Vec<String>, Box<dyn Error>> {
    let mut arg_list = vec![];
    for arg in command {
        arg_list.extend(parse_arg(arg)?);
    }
    Ok(arg_list)
}

impl<T> InteractiveParse for T
where T: Parser {
    fn interactive_parse() -> Result<Self, Box<dyn Error>> {
        let base_command = T::command();
        let mut args = vec![base_command.get_name().to_string()];
        let mut command = &base_command;
        loop {
            args.extend(get_args(command.get_arguments())?);
            let subcommands: Vec<&Command> = command.get_subcommands().collect();
            if subcommands.len() == 0 { break; }
            command = Select::new(command.get_name(), subcommands).prompt()?;
            args.push(command.get_name().to_string());
        }
        Ok(T::parse_from(args))
    }
}

#[cfg(test)]
mod test {
    use super::*;

    #[derive(Parser, Debug)]
    #[command(author, version, about, long_about = None)]
    struct Git {
        #[command(subcommand)]
        subcommand: SubCommand,

        /// MyArg help string
        #[arg(required=false)]
        my_arg: Option<String>
    }

    #[derive(Parser, Debug)]
    #[clap(rename_all = "snake_case", infer_subcommands=true)]
    enum SubCommand {
        Commit {
            #[arg(required=false)]
            message: Option<String>
        },
        Clone {
            address: Vec<String>
        },
        Merge {
            #[arg(value_delimiter=',')]
            address: Vec<String>
        }
    }

    #[ignore]
    #[test]
    fn test_interactive() {
        let git = Git::interactive_parse().unwrap();
        println!("{:?}", git);   
    }

    #[ignore]
    #[test]
    fn test_static() {
        let args = ["git", "-h"];
        let git = Git::parse_from(args);
        println!("{:?}", git);   
    }
}