state

.cade

@@ -0,0 +1,2 @@
+pure
+load flake

Cargo.lock

@@ -104,6 +104,8 @@ dependencies = [
  "bincode",
  "clap",
  "microxdg",
+ "serde",
+ "serde_json",
  "sled",
 ]
 
@@ -223,6 +225,12 @@ version = "1.70.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7943c866cc5cd64cbc25b2e01621d07fa8eb2a1a23160ee81ce38704e97b8ecf"
 
+[[package]]
+name = "itoa"
+version = "1.0.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4a5f13b858c8d314ee3e8f639011f7ccefe71f97f96e50151fb991f267928e2c"
+
 [[package]]
 name = "libc"
 version = "0.2.175"
@@ -245,6 +253,12 @@ version = "0.4.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "13dc2df351e3202783a1fe0d44375f7295ffb4049267b0f3018346dc122a1d94"
 
+[[package]]
+name = "memchr"
+version = "2.7.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32a282da65faaf38286cf3be983213fcf1d2e2a58700e808f83f4ea9a4804bc0"
+
 [[package]]
 name = "microxdg"
 version = "0.2.0"
@@ -309,6 +323,12 @@ dependencies = [
  "bitflags",
 ]
 
+[[package]]
+name = "ryu"
+version = "1.0.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "28d3b2b1366ec20994f1fd18c3c594f05c5dd4bc44d8bb0c1c632c8d6829481f"
+
 [[package]]
 name = "scopeguard"
 version = "1.2.0"
@@ -317,24 +337,47 @@ checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
 [[package]]
 name = "serde"
-version = "1.0.219"
+version = "1.0.226"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5f0e2c6ed6606019b4e29e69dbaba95b11854410e5347d525002456dbbb786b6"
+checksum = "0dca6411025b24b60bfa7ec1fe1f8e710ac09782dca409ee8237ba74b51295fd"
+dependencies = [
+ "serde_core",
+ "serde_derive",
+]
+
+[[package]]
+name = "serde_core"
+version = "1.0.226"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba2ba63999edb9dac981fb34b3e5c0d111a69b0924e253ed29d83f7c99e966a4"
 dependencies = [
  "serde_derive",
 ]
 
 [[package]]
 name = "serde_derive"
-version = "1.0.219"
+version = "1.0.226"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5b0276cf7f2c73365f7157c8123c21cd9a50fbbd844757af28ca1f5925fc2a00"
+checksum = "8db53ae22f34573731bafa1db20f04027b2d25e02d8205921b569171699cdb33"
 dependencies = [
  "proc-macro2",
  "quote",
  "syn",
 ]
 
+[[package]]
+name = "serde_json"
+version = "1.0.145"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "402a6f66d8c709116cf22f558eab210f5a50187f702eb4d7e5ef38d9a7f1c79c"
+dependencies = [
+ "itoa",
+ "memchr",
+ "ryu",
+ "serde",
+ "serde_core",
+]
+
 [[package]]
 name = "sled"
 version = "0.34.7"

Cargo.toml

@@ -15,4 +15,6 @@ anyhow = "1.0.99"
 bincode = "2.0.1"
 clap = { version = "4.5.45", features = ["derive"] }
 microxdg = "0.2.0"
+serde = { version = "1.0.226", features = ["derive"] }
+serde_json = "1.0.145"
 sled = "0.34.7"

src/actions.rs

@@ -0,0 +1,270 @@
+use crate::types::{CadeActions, Env};
+use anyhow::{Context, Result, anyhow, bail};
+use serde_json::Value;
+use std::{
+    collections::HashMap,
+    ffi::OsString,
+    fmt::{Debug, Display},
+    io::{BufRead, Read},
+    path::{Path, PathBuf},
+};
+type RawEnv = Vec<(String, Vec<String>)>;
+
+#[repr(u8)]
+#[derive(bincode::Encode, bincode::Decode, PartialEq, Debug)]
+pub enum Permission {
+    Allowed,
+    Disallowed,
+}
+
+impl Display for Permission {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        Debug::fmt(self, f)
+    }
+}
+
+pub fn load_flake(path: &Path, output: Option<String>) -> Result<RawEnv> {
+    let mut nix_cmd = String::from("nix print-dev-env --json");
+    if let Some(flake_output) = output {
+        nix_cmd.push_str(&[" ", &flake_output, " "].concat());
+    }
+    let mut proc = std::process::Command::new("sh");
+    // proc.env_clear();
+    proc.arg("-c");
+    proc.arg(nix_cmd);
+    proc.current_dir(path);
+    let output = proc
+        .output()
+        .with_context(|| format!("loading flake at {}", path.display()))?
+        .stdout;
+    let json: Value = serde_json::from_slice(&output).context("parsing output as json")?;
+    parse_json(json)
+}
+
+pub fn load_shell(path: &Path, filename: String) -> Result<CadeActions> {
+    let mut nix_cmd = String::from("nix print-dev-env --json ");
+    // let mut nix_cmd = String::from("nix-shell ");
+    if !filename.is_empty() {
+        nix_cmd.push_str(&["-F ", &filename].concat());
+    } else {
+        nix_cmd.push_str(&["-F ./shell.nix"].concat());
+    }
+    // nix_cmd.push_str("--pure --command env --null");
+    let mut proc = std::process::Command::new("sh");
+    proc.env_clear();
+    proc.arg("-c");
+    proc.arg(nix_cmd);
+    proc.current_dir(path);
+    let output = proc
+        .output()
+        .with_context(|| format!("loading shell at {}", path.display()))?
+        .stdout;
+    let json: Value = serde_json::from_slice(&output).context("parsing output as json")?;
+    parse_json(json)
+}
+
+pub fn load_env(path: &Path, filename: String) -> Result<CadeActions> {
+    let mut p = path.to_path_buf();
+    if filename.is_empty() {
+        p.push(".env");
+    } else {
+        p.push(filename);
+    }
+    let mut file = std::fs::File::open(p)
+        .with_context(|| format!("opening env file at {}", path.display()))?;
+    let mut buf = String::new();
+    file.read_to_string(&mut buf).context("reading env file")?;
+    parse_envs(buf)
+}
+
+pub fn call(path: &Path, argv: Vec<String>) -> Result<CadeActions> {
+    let mut it = argv.iter();
+    // safety: already checked at parsing
+    let mut process = std::process::Command::new(it.next().unwrap());
+    process.current_dir(path);
+    process.args(it);
+    let output = process
+        .output()
+        .with_context(|| format!("running process {}", argv.concat()))?
+        .stdout;
+
+    let text = String::from_utf8(output)
+        .with_context(|| format!("converting call {} output to text", argv.concat()))?
+        .replace(' ', "\0");
+    parse_envs(text)
+}
+
+fn parse_envs(text: String) -> Result<RawEnv> {
+    let mut envs = Vec::new();
+    for line in text.lines() {
+           let split: Vec<&str> = line.split('=').collect();
+        let parse = match split.len() {
+            3 => {
+               let key = split[0];
+               let values = &split[2].split(":").to_owned().collect();
+            }
+            2 => {
+            // TODO
+            }
+            _ => {
+                return Err(anyhow!("parsing variable from {text}"));
+            }
+            // 1 => Clear(split[0].to_string()),
+            // _ => Add(split[0].to_string(), split[1..].concat().to_string()),
+        };
+        envs.push(parse);
+    }
+    Ok(envs)
+}
+
+fn parse_json(json: Value) -> Result<RawEnv> {
+    if json.is_object()
+        && let Some(all_vars) = json.get("variables")
+    {
+        let vars = all_vars
+            .as_object()
+            .map(|inner| {
+                inner
+                    .iter()
+                    .filter(|(var, _)| match var.as_str() {
+                        "NIX_BUILD_TOP"
+                        | "NIX_BUILD_CORES"
+                        | "NIX_STORE"
+                        | "TEMP"
+                        | "TEMPDIR"
+                        | "TMP"
+                        | "TMPDIR"
+                        | "builder"
+                        | "out"
+                        | "stdenv"
+                        | "system"
+                        | "dontAddDisableDepTrack"
+                        | "outputs" => false,
+                        _ => true,
+                    })
+                    .filter_map(|var| {
+                        Some((var.0.to_string(), var.1.get("value")?.as_str()?.to_owned()))
+                    })
+                    .map(|(name, value)| {
+                        (
+                            name,
+                            value
+                                .split(':')
+                                .map(|s| s.to_string())
+                                .collect::<Vec<String>>(),
+                        )
+                    })
+                    .collect()
+            })
+            .context("collecting env vars")?;
+        Ok(vars)
+    } else {
+        Err(anyhow!("failed to parse PATH value from JSON output"))
+    }
+}
+
+pub fn do_activation() -> Result<()> {
+    let dir = ensure_dir()?;
+    let db = sled::open(dir).context("open database")?;
+    let cwd = std::env::current_dir()
+        .context("determine CWD")?
+        .into_os_string();
+
+    if db
+        .get(cwd.into_encoded_bytes())
+        .map(|perm| {
+            perm.map(|inner| {
+                let (p, _) =
+                    bincode::decode_from_slice(inner.as_ref(), bincode::config::standard())
+                        .unwrap_or((Permission::Disallowed, 0));
+                p
+            })
+            .unwrap_or(Permission::Disallowed)
+        })
+        .unwrap_or(Permission::Disallowed)
+        == Permission::Disallowed
+    {
+        bail!("cade is not permitted to operate here; use 'cade allow'.");
+    }
+
+    let mut current_dir = std::env::current_dir().context("determine CWD")?;
+    let base_env = std::env::vars().collect::<HashMap<String, String>>();
+
+    use crate::core::{read_cade, realise};
+    let mut cascade = HashMap::new();
+    cascade.insert(
+        current_dir.clone(),
+        read_cade(&current_dir.join(".cade")).context("reading cade file")?,
+    );
+
+    while let Some(parent) = current_dir.parent()
+        && std::fs::exists(parent.join(".cade"))
+            .context("check for .cade file in parent directory")?
+    {
+        current_dir = parent.to_path_buf();
+        cascade.insert(
+            current_dir.clone(),
+            read_cade(&current_dir.join(".cade")).context("reading cade file")?,
+        );
+    }
+
+    let mut env = HashMap::new();
+    let adjustments = realise(cascade)?;
+    use CadeActions::*;
+    for action in adjustments {
+        match action {
+            Environ(env_actions) => {
+                for action in env_actions {
+                    env.entry(action.name)
+                        .and_modify(|iv: &mut Vec<String>| {
+                            iv.extend(action.value);
+                        })
+                        .or_insert(action.value);
+                }
+            }
+            Purify => {
+                for (bk, bv) in base_env.iter() {
+                    env.entry(bk).and_modify(|inner| inner)
+                    if env.get(bk).is_some_and(|inner| inner.contains(bv)) {
+                        env.remove(bk);
+                    }
+                }
+            }
+            Hook(hook) => {}
+        };
+    }
+    for (k, v) in env {
+        println!("{k}={v}");
+    }
+    Ok(())
+}
+
+pub fn set_permission(permission: Permission) -> Result<()> {
+    let dir = ensure_dir()?;
+    let db = sled::open(dir).context("open database")?;
+    let cwd = std::env::current_dir()
+        .context("determine CWD")?
+        .into_os_string();
+    let encoded_permission = bincode::encode_to_vec(&permission, bincode::config::standard())
+        .context("encode permission value")?;
+
+    let _ = db
+        .insert(cwd.into_encoded_bytes(), encoded_permission)
+        .context("update permissions database")?;
+    eprintln!(
+        "cade is now {} here.",
+        permission.to_string().to_lowercase()
+    );
+    Ok(())
+}
+
+fn ensure_dir() -> Result<PathBuf> {
+    let xdg = microxdg::Xdg::new().context("establish XDG paths")?;
+    let mut path = xdg.state().context("find xdg state dir")?;
+    path.push("cade");
+    if !std::fs::exists(&path).is_ok_and(|v| v) {
+        std::fs::create_dir(&path).context("create cade's state path")?;
+    }
+    path.push("permissions.db");
+    Ok(path)
+}

src/cli/clap.rs

@@ -0,0 +1,14 @@
+use clap::{Parser, Subcommand};
+#[derive(Subcommand)]
+pub enum CliAction {
+    Enter,
+    Allow,
+    Disallow,
+    Edit,
+}
+
+#[derive(Parser)]
+pub struct Cli {
+    #[command(subcommand)]
+    pub action: CliAction,
+}

src/cli/mod.rs

@@ -0,0 +1,2 @@
+pub mod clap;
+pub mod parse;

src/cli/parse.rs

@@ -0,0 +1,98 @@
+use crate::Debug;
+use crate::types::*;
+use std::{fmt::Display, str::FromStr};
+
+#[derive(Debug)]
+enum ParseError {
+    InvalidKeyword,
+    UnknownLoadable,
+    TooManyOptions,
+    TooFewOptions,
+}
+
+impl Display for ParseError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        Debug::fmt(self, f)
+    }
+}
+
+impl FromStr for Keyword {
+    type Err = ParseError;
+    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
+        let lower = s.to_lowercase();
+        use crate::types::Keyword::*;
+        if s.len() >= 4 {
+            let res = match &lower.get(..4) {
+                Some("pure") => Pure,
+                Some("call") => {
+                    let target: Vec<String> = lower[4..]
+                        .split_whitespace()
+                        .map(|s| s.to_owned())
+                        .collect();
+                    if target.is_empty() {
+                        return Err(ParseError::TooFewOptions);
+                    }
+                    Call(target)
+                }
+                Some("load") => {
+                    let mut words = lower[4..].split_whitespace();
+                    if words.clone().count() > 2 {
+                        return Err(ParseError::TooManyOptions);
+                    } else {
+                        match words.next() {
+                            None => Load(Loadable::Default),
+                            Some("shell") => {
+                                Load(Loadable::Shell(s.get(11..).unwrap_or("").to_string()))
+                            }
+                            Some("flake") => {
+                                Load(Loadable::Flake(s.get(11..).unwrap_or("").to_string()))
+                            }
+                            Some("env") => {
+                                Load(Loadable::Env(s.get(9..).unwrap_or("").to_string()))
+                            }
+                            Some(_) => return Err(ParseError::UnknownLoadable),
+                        }
+                    }
+                }
+                Some("hook") => {
+                    let mut words = lower[4..].split_whitespace();
+                    let mut p = words.clone().peekable();
+                    use crate::types::HookType::*;
+                    Hook(crate::types::Hook {
+                        kind: match p.peek() {
+                            None => return Err(ParseError::TooFewOptions),
+                            Some(&"preload") => {
+                                words.next();
+                                LoadPre
+                            }
+                            Some(&"load") => {
+                                words.next();
+                                LoadPost
+                            }
+                            Some(&"preunload") => {
+                                words.next();
+                                UnloadPre
+                            }
+                            Some(&"unload") => {
+                                words.next();
+                                UnloadPost
+                            }
+                            Some(_) => LoadPost,
+                        },
+                        content: words.map(|s| s.to_owned()).collect(),
+                    })
+                }
+                Some(n) => {
+                    eprintln!("found invalid command: {n}");
+                    return Err(ParseError::InvalidKeyword);
+                }
+                None => {
+                    return Err(ParseError::InvalidKeyword);
+                }
+            };
+            Ok(res)
+        } else {
+            Err(ParseError::InvalidKeyword)
+        }
+    }
+}

src/core.rs

@@ -0,0 +1,44 @@
+use crate::types::{CadeActions, Keyword, Loadable};
+use anyhow::{Context, Result, anyhow};
+use std::{
+    collections::HashMap,
+    io::BufRead,
+    path::{Path, PathBuf},
+};
+
+pub fn read_cade(path: &Path) -> Result<Vec<Keyword>> {
+    let contents = std::fs::read(path).context("reading cade file")?;
+    let mut accum = Vec::new();
+    let mut lines = contents.lines();
+    while let Some(Ok(line)) = lines.next() {
+        let instruction: Keyword = line
+            .parse()
+            .map_err(|e| anyhow!("while parsing cade file at {}: {e:?}", path.display()))?;
+        accum.push(instruction);
+    }
+    Ok(accum)
+}
+
+pub fn realise(cascade: HashMap<PathBuf, Vec<Keyword>>) -> Result<Vec<CadeActions>> {
+    let mut actions: Vec<CadeActions> = Vec::new();
+    use crate::actions::*;
+    for (path, layer) in cascade {
+        for keyword in layer {
+            use Keyword::*;
+            use Loadable::*;
+            let acts = match keyword {
+                Pure => Ok(CadeActions::Purify),
+                Call(argv) => call(&path, argv).context("calling process"),
+                Load(loadable) => match loadable {
+                    Default => load_flake(&path, None).context("loading flake"),
+                    Flake(output) => load_flake(&path, Some(output)),
+                    Shell(filename) => load_shell(&path, filename).context("loading shell"),
+                    Env(filename) => load_env(&path, filename).context("loading env file"),
+                },
+                Hook(hook) => Ok(CadeActions::Hook(hook)),
+            }?;
+            actions.push(acts);
+        }
+    }
+    Ok(actions)
+}

src/main.rs

@@ -1,355 +1,26 @@
+mod actions;
+mod cli;
+mod core;
+mod types;
+
 use std::{
     collections::HashMap,
     ffi::OsString,
     fmt::{Debug, Display},
     io::{BufRead, Read},
-    os::unix::process::CommandExt,
     path::{Path, PathBuf},
-    str::{FromStr, SplitWhitespace},
 };
 
 use anyhow::{Context, Result, anyhow, bail};
-use clap::{Parser, Subcommand};
-
-#[repr(u8)]
-#[derive(bincode::Encode, bincode::Decode, PartialEq, Debug)]
-enum Permission {
-    Allowed,
-    Disallowed,
-}
-impl Display for Permission {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        Debug::fmt(self, f)
-    }
-}
-
-#[derive(Subcommand)]
-enum Action {
-    Activate,
-    Allow,
-    Disallow,
-    Edit,
-}
-
-#[derive(Parser)]
-struct Cli {
-    #[command(subcommand)]
-    action: Action,
-}
-
-#[derive(Debug)]
-enum Loadable {
-    Default,
-    Flake(String),
-    Shell(String),
-    Env(String),
-}
-
-#[derive(Debug)]
-enum Keyword {
-    Pure,
-    Call(Vec<String>),
-    Load(Loadable),
-}
-
-#[derive(Debug)]
-enum ParseError {
-    InvalidKeyword,
-    UnknownLoadable,
-    TooManyOptions,
-    TooFewOptions,
-}
-impl Display for ParseError {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        Debug::fmt(self, f)
-    }
-}
-
-impl FromStr for Keyword {
-    type Err = ParseError;
-    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
-        let lower = s.to_lowercase();
-        use Keyword::*;
-        if s.len() >= 4 {
-            let res = match &lower.get(..4) {
-                Some("pure") => Pure,
-                Some("call") => {
-                    let target: Vec<String> = lower[4..]
-                        .split_whitespace()
-                        .map(|s| s.to_owned())
-                        .collect();
-                    if target.is_empty() {
-                        return Err(ParseError::TooFewOptions);
-                    }
-                    Call(target)
-                }
-                Some("load") => {
-                    let mut words = lower[4..].split_whitespace();
-                    if words.clone().count() > 2 {
-                        return Err(ParseError::TooManyOptions);
-                    } else {
-                        match words.next() {
-                            None => Load(Loadable::Default),
-                            Some("shell") => {
-                                Load(Loadable::Shell(s.get(11..).unwrap_or("").to_string()))
-                            }
-                            Some("flake") => {
-                                Load(Loadable::Flake(s.get(11..).unwrap_or("").to_string()))
-                            }
-                            Some("env") => {
-                                Load(Loadable::Env(s.get(9..).unwrap_or("").to_string()))
-                            }
-                            Some(_) => return Err(ParseError::UnknownLoadable),
-                        }
-                    }
-                }
-                Some(n) => {
-                    eprintln!("found invalid command {n}, dying..");
-                    return Err(ParseError::InvalidKeyword);
-                }
-                None => {
-                    return Err(ParseError::InvalidKeyword);
-                }
-            };
-            Ok(res)
-        } else {
-            Err(ParseError::InvalidKeyword)
-        }
-    }
-}
-
-fn read_cade(path: &Path) -> Result<Vec<Keyword>> {
-    let contents = std::fs::read(path).context("reading cade file")?;
-    let mut accum = Vec::new();
-    let mut lines = contents.lines();
-    while let Some(Ok(line)) = lines.next() {
-        let instruction: Keyword = line
-            .parse()
-            .map_err(|e| anyhow!("while parsing cade file at {}: {e:?}", path.display()))?;
-        accum.push(instruction);
-    }
-    Ok(accum)
-}
-
-#[derive(Debug)]
-enum EnvAction {
-    Add(String, String),
-    Clear(String),
-    Purify,
-}
-
-fn load_flake(path: &Path, output: Option<String>) -> Result<Vec<EnvAction>> {
-    let mut nix_cmd = String::from("nix develop ");
-    if let Some(flake_output) = output {
-        nix_cmd.push_str(&[&flake_output, " "].concat());
-    }
-    nix_cmd.push_str("-ic env --null");
-    let mut proc = std::process::Command::new("sh");
-    // proc.env_clear();
-    proc.arg("-c");
-    proc.arg(nix_cmd);
-    proc.current_dir(path);
-    let output = proc
-        .output()
-        .with_context(|| format!("loading flake at {}", path.display()))?
-        .stdout;
-    let text = String::from_utf8(output).context("converting output to text")?;
-    parse_envs(text)
-}
-
-fn load_shell(path: &Path, filename: String) -> Result<Vec<EnvAction>> {
-    let mut nix_cmd = String::from("nix-shell ");
-    if filename.is_empty() {
-        nix_cmd.push_str(&[&filename, " "].concat());
-    }
-    nix_cmd.push_str("--pure --command env --null");
-    let mut proc = std::process::Command::new("sh");
-    proc.env_clear();
-    proc.arg("-c");
-    proc.arg(nix_cmd);
-    proc.current_dir(path);
-    let output = proc
-        .output()
-        .with_context(|| format!("loading shell at {}", path.display()))?
-        .stdout;
-    let text = String::from_utf8(output).context("converting output to text")?;
-    parse_envs(text)
-}
-
-fn load_env(path: &Path, filename: String) -> Result<Vec<EnvAction>> {
-    let mut p = path.to_path_buf();
-    if filename.is_empty() {
-        p.push(".env");
-    } else {
-        p.push(filename);
-    }
-    let mut file = std::fs::File::open(p)
-        .with_context(|| format!("opening env file at {}", path.display()))?;
-    let mut buf = String::new();
-    file.read_to_string(&mut buf).context("reading env file")?;
-    parse_envs(buf)
-}
-
-fn call(path: &Path, argv: Vec<String>) -> Result<Vec<EnvAction>> {
-    let mut it = argv.iter();
-    // safety: already checked at parsing
-    let mut process = std::process::Command::new(it.next().unwrap());
-    process.current_dir(path);
-    process.args(it);
-    let output = process
-        .output()
-        .with_context(|| format!("running process {}", argv.concat()))?
-        .stdout;
-
-    let text = String::from_utf8(output)
-        .with_context(|| format!("converting call {} output to text", argv.concat()))?
-        .replace(' ', "\0");
-    parse_envs(text)
-}
-
-fn parse_envs(text: String) -> Result<Vec<EnvAction>> {
-    let mut envs = Vec::new();
-    use EnvAction::*;
-    for line in text.split('\0') {
-        let split: Vec<&str> = line.split('=').collect();
-        let parse = match split.len() {
-            0 => {
-                return Err(anyhow!("processing returned env var {text}"));
-            }
-            1 => Clear(split[0].to_string()),
-            _ => Add(split[0].to_string(), split[1..].concat().to_string()),
-        };
-        envs.push(parse);
-    }
-    Ok(envs)
-}
-
-fn interpret(cascade: HashMap<PathBuf, Vec<Keyword>>) -> Result<Vec<EnvAction>> {
-    let mut actions = Vec::new();
-    for (path, layer) in cascade {
-        for keyword in layer {
-            use EnvAction::*;
-            use Keyword::*;
-            use Loadable::*;
-            let acts = match keyword {
-                Pure => Ok(Vec::from([Purify])),
-                Call(argv) => call(&path, argv).context("calling process"),
-                Load(loadable) => match loadable {
-                    Default => load_flake(&path, None).context("loading flake"),
-                    Flake(output) => load_flake(&path, Some(output)),
-                    Shell(filename) => load_shell(&path, filename).context("loading shell"),
-                    Env(filename) => load_env(&path, filename).context("loading env file"),
-                },
-            }?;
-            actions.extend(acts);
-        }
-    }
-    Ok(actions)
-}
-
-fn do_activation() -> Result<()> {
-    let dir = ensure_dir()?;
-    let db = sled::open(dir).context("open database")?;
-    let cwd = std::env::current_dir()
-        .context("determine CWD")?
-        .into_os_string();
-
-    if db
-        .get(cwd.into_encoded_bytes())
-        .map(|perm| {
-            perm.map(|inner| {
-                let (p, _) =
-                    bincode::decode_from_slice(inner.as_ref(), bincode::config::standard())
-                        .unwrap_or((Permission::Disallowed, 0));
-                p
-            })
-            .unwrap_or(Permission::Disallowed)
-        })
-        .unwrap_or(Permission::Disallowed)
-        == Permission::Disallowed
-    {
-        bail!("cade is not permitted to operate here; use 'cade allow'.");
-    }
-
-    let mut current_dir = std::env::current_dir().context("determine CWD")?;
-    let base_env = std::env::vars().collect::<HashMap<String, String>>();
-
-    let mut cascade = HashMap::new();
-    cascade.insert(
-        current_dir.clone(),
-        read_cade(&current_dir.join(".cade")).context("reading cade file")?,
-    );
-
-    while let Some(parent) = current_dir.parent()
-        && std::fs::exists(parent.join(".cade"))
-            .context("check for .cade file in parent directory")?
-    {
-        current_dir = parent.to_path_buf();
-        cascade.insert(
-            current_dir.clone(),
-            read_cade(&current_dir.join(".cade")).context("reading cade file")?,
-        );
-    }
-
-    let mut env = HashMap::new();
-    let adjustments = interpret(cascade)?;
-    use EnvAction::*;
-    for action in adjustments {
-        let _ = match action {
-            Add(k, v) => env.insert(k, v),
-            Clear(k) => env.remove(&k),
-            Purify => {
-                for (bk, bv) in base_env.iter() {
-                    if env.get(bk).is_some_and(|inner| inner == bv) {
-                        env.remove(bk);
-                    }
-                }
-                None
-            }
-        };
-    }
-    for (k, v) in env {
-        println!("{k}={v}");
-    }
-    Ok(())
-}
-
-fn set_permission(permission: Permission) -> Result<()> {
-    let dir = ensure_dir()?;
-    let db = sled::open(dir).context("open database")?;
-    let cwd = std::env::current_dir()
-        .context("determine CWD")?
-        .into_os_string();
-    let encoded_permission = bincode::encode_to_vec(&permission, bincode::config::standard())
-        .context("encode permission value")?;
-
-    let _ = db
-        .insert(cwd.into_encoded_bytes(), encoded_permission)
-        .context("update permissions database")?;
-    eprintln!(
-        "cade is now {} here.",
-        permission.to_string().to_lowercase()
-    );
-    Ok(())
-}
-
-fn ensure_dir() -> Result<PathBuf> {
-    let xdg = microxdg::Xdg::new().context("establish XDG paths")?;
-    let mut path = xdg.state().context("find xdg state dir")?;
-    path.push("cade");
-    if !std::fs::exists(&path).is_ok_and(|v| v) {
-        std::fs::create_dir(&path).context("create cade's state path")?;
-    }
-    path.push("permissions.db");
-    Ok(path)
-}
+use clap::Parser;
 
 fn try_main() -> Result<()> {
-    let args = Cli::parse();
-    use Action::*;
+    let args = cli::clap::Cli::parse();
+    use crate::actions::*;
+    use cli::clap::CliAction::*;
     match args.action {
-        // TODO recursively ascend until we hit a top level .cade, then activate downwards
-        Activate => do_activation().context("activate cade environment")?,
+        // TODO recursively ascend until we hit a top level .cade, then activate downwards (ie. in reverse)
+        Enter => do_activation().context("activate cade environment")?,
         Allow => set_permission(Permission::Allowed)?,
         Disallow => set_permission(Permission::Disallowed)?,
         Edit => {

src/types.rs

@@ -0,0 +1,47 @@
+use std::path::PathBuf;
+
+#[derive(Debug)]
+pub enum CadeActions {
+    Purify,
+    Environ(Vec<Env>),
+    Hook(Hook),
+}
+
+#[derive(Debug)]
+pub struct Env {
+    pub name: String,
+    pub value: Vec<String>,
+    pub origin: PathBuf,
+    pub kind: Loadable,
+    pub layer: u8,
+}
+
+#[derive(Debug)]
+pub enum Keyword {
+    Pure,
+    Call(Vec<String>),
+    Load(Loadable),
+    Hook(Hook),
+}
+
+#[derive(Debug)]
+pub enum Loadable {
+    Default,
+    Flake(String),
+    Shell(String),
+    Env(String),
+}
+
+#[derive(Debug)]
+pub enum HookType {
+    LoadPre,
+    LoadPost,
+    UnloadPre,
+    UnloadPost,
+}
+
+#[derive(Debug)]
+pub struct Hook {
+    pub content: Vec<String>,
+    pub kind: HookType,
+}