use derive_new::new;
use rustyline::completion::Completer;
use rustyline::completion::{self, FilenameCompleter};
use rustyline::line_buffer::LineBuffer;

#[derive(new)]
crate struct NuCompleter {
    pub file_completer: FilenameCompleter,
    //pub commands: indexmap::IndexMap<String, Arc<dyn Command>>,
}

pub struct CompletionPair {
    pub display: String,
    pub replacement: String,
}

impl Into<completion::Pair> for CompletionPair {
    fn into(self) -> completion::Pair {
        completion::Pair {
            display: self.display,
            replacement: self.replacement,
        }
    }
}

impl NuCompleter {
    /*
    pub fn complete(
        &self,
        line: &str,
        pos: usize,
        context: &rustyline::Context,
    ) -> rustyline::Result<(usize, Vec<CompletionPair>)> {
        //let commands: Vec<String> = self.commands.keys().cloned().collect();

        let mut completions = self.file_completer.complete(line, pos, context)?.1;

        for completion in &mut completions {
            if completion.replacement.contains("\\ ") {
                completion.replacement = completion.replacement.replace("\\ ", " ");
            }
            if completion.replacement.contains("\\(") {
                completion.replacement = completion.replacement.replace("\\(", "(");
            }

            if completion.replacement.contains(" ") || completion.replacement.contains("(") {
                if !completion.replacement.starts_with("\"") {
                    completion.replacement = format!("\"{}", completion.replacement);
                }
                if !completion.replacement.ends_with("\"") {
                    completion.replacement = format!("{}\"", completion.replacement);
                }
            }
        }

        let line_chars: Vec<_> = line.chars().collect();
        let mut replace_pos = pos;
        while replace_pos > 0 {
            if line_chars[replace_pos - 1] == ' ' {
                break;
            }
            replace_pos -= 1;
        }

        /*
        for command in commands.iter() {
            let mut pos = replace_pos;
            let mut matched = true;
            if pos < line_chars.len() {
                for chr in command.chars() {
                    if line_chars[pos] != chr {
                        matched = false;
                        break;
                    }
                    pos += 1;
                    if pos == line_chars.len() {
                        break;
                    }
                }
            }

            if matched {
                completions.push(CompletionPair {
                    display: command.clone(),
                    replacement: command.clone(),
                });
            }
        }
        */

        Ok((replace_pos, completions))
    }
    */

    fn update(&self, line: &mut LineBuffer, start: usize, elected: &str) {
        let end = line.pos();
        line.replace(start..end, elected)
    }
}