use crate::{evaluate::scope::Scope, EvaluationContext};
use indexmap::IndexMap;
use nu_data::config::path::{default_history_path, history_path};
use nu_errors::ShellError;
use nu_protocol::{Signature, TaggedDictBuilder, UntaggedValue, Value};
use nu_source::{Spanned, Tag};

pub fn nu(
    scope: &Scope,
    tag: impl Into<Tag>,
    ctx: &EvaluationContext,
) -> Result<Value, ShellError> {
    let env = &scope.get_env_vars();
    let tag = tag.into();

    let mut nu_dict = TaggedDictBuilder::new(&tag);

    let mut dict = TaggedDictBuilder::new(&tag);
    for v in env.iter() {
        if v.0 != "PATH" && v.0 != "Path" {
            dict.insert_untagged(v.0, UntaggedValue::string(v.1));
        }
    }

    nu_dict.insert_value("env", dict.into_value());

    nu_dict.insert_value(
        "history-path",
        UntaggedValue::filepath(default_history_path()).into_value(&tag),
    );

    if let Some(global_cfg) = &ctx.configs.lock().global_config {
        nu_dict.insert_value(
            "config",
            UntaggedValue::row(global_cfg.vars.clone()).into_value(&tag),
        );

        nu_dict.insert_value(
            "config-path",
            UntaggedValue::filepath(global_cfg.file_path.clone()).into_value(&tag),
        );

        // overwrite hist-path if present
        if let Some(hist_path) = history_path(global_cfg) {
            nu_dict.insert_value(
                "history-path",
                UntaggedValue::filepath(hist_path).into_value(&tag),
            );
        }
    }

    let mut table = vec![];
    for v in env.iter() {
        if v.0 == "PATH" || v.0 == "Path" {
            for path in std::env::split_paths(&v.1) {
                table.push(UntaggedValue::filepath(path).into_value(&tag));
            }
        }
    }
    nu_dict.insert_value("path", UntaggedValue::table(&table).into_value(&tag));

    let path = std::env::current_dir()?;
    nu_dict.insert_value("cwd", UntaggedValue::filepath(path).into_value(&tag));

    if let Some(home) = crate::filesystem::filesystem_shell::homedir_if_possible() {
        nu_dict.insert_value("home-dir", UntaggedValue::filepath(home).into_value(&tag));
    }

    let temp = std::env::temp_dir();
    nu_dict.insert_value("temp-dir", UntaggedValue::filepath(temp).into_value(&tag));

    #[cfg(feature = "rustyline-support")]
    {
        let keybinding_path = nu_data::keybinding::keybinding_path()?;
        nu_dict.insert_value(
            "keybinding-path",
            UntaggedValue::filepath(keybinding_path).into_value(&tag),
        );
    }

    Ok(nu_dict.into_value())
}

pub fn scope(
    aliases: &IndexMap<String, Vec<Spanned<String>>>,
    commands: &IndexMap<String, Signature>,
    tag: impl Into<Tag>,
) -> Result<Value, ShellError> {
    let tag = tag.into();

    let mut scope_dict = TaggedDictBuilder::new(&tag);

    let mut aliases_dict = TaggedDictBuilder::new(&tag);
    for v in aliases.iter() {
        let values = v.1.clone();
        let mut vec = Vec::new();

        for k in values.iter() {
            vec.push(k.to_string());
        }

        let alias = vec.join(" ");

        aliases_dict.insert_untagged(v.0, UntaggedValue::string(alias));
    }

    let mut commands_dict = TaggedDictBuilder::new(&tag);
    for (name, signature) in commands.iter() {
        commands_dict.insert_untagged(name, UntaggedValue::string(&signature.allowed().join(" ")))
    }

    scope_dict.insert_value("aliases", aliases_dict.into_value());

    scope_dict.insert_value("commands", commands_dict.into_value());

    Ok(scope_dict.into_value())
}