Cargo.lock

@@ -17,6 +17,56 @@ version = "0.2.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "683d7910e743518b0e34f1186f92494becacb047c7b6bf616c96772180fef923"
 
+[[package]]
+name = "anstream"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "824a212faf96e9acacdbd09febd34438f8f711fb84e09a8916013cd7815ca28d"
+dependencies = [
+ "anstyle",
+ "anstyle-parse",
+ "anstyle-query",
+ "anstyle-wincon",
+ "colorchoice",
+ "is_terminal_polyfill",
+ "utf8parse",
+]
+
+[[package]]
+name = "anstyle"
+version = "1.0.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "940b3a0ca603d1eade50a4846a2afffd5ef57a9feac2c0e2ec2e14f9ead76000"
+
+[[package]]
+name = "anstyle-parse"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "52ce7f38b242319f7cabaa6813055467063ecdc9d355bbb4ce0c68908cd8130e"
+dependencies = [
+ "utf8parse",
+]
+
+[[package]]
+name = "anstyle-query"
+version = "1.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "40c48f72fd53cd289104fc64099abca73db4166ad86ea0b4341abe65af83dadc"
+dependencies = [
+ "windows-sys",
+]
+
+[[package]]
+name = "anstyle-wincon"
+version = "3.0.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "291e6a250ff86cd4a820112fb8898808a366d8f9f58ce16d1f538353ad55747d"
+dependencies = [
+ "anstyle",
+ "once_cell_polyfill",
+ "windows-sys",
+]
+
 [[package]]
 name = "anyhow"
 version = "1.0.102"
@@ -103,14 +153,18 @@ dependencies = [
 
 [[package]]
 name = "cenv-rs"
-version = "0.1.0"
+version = "0.2.0"
 dependencies = [
+ "clap",
  "crossterm",
  "dirs",
  "ratatui",
  "serde",
+ "serde_json",
+ "serde_yaml",
  "tempfile",
  "toml",
+ "tui-input",
 ]
 
 [[package]]
@@ -125,6 +179,52 @@ version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "613afe47fcd5fac7ccf1db93babcb082c5994d996f20b8b159f2ad1658eb5724"
 
+[[package]]
+name = "clap"
+version = "4.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b193af5b67834b676abd72466a96c1024e6a6ad978a1f484bd90b85c94041351"
+dependencies = [
+ "clap_builder",
+ "clap_derive",
+]
+
+[[package]]
+name = "clap_builder"
+version = "4.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "714a53001bf66416adb0e2ef5ac857140e7dc3a0c48fb28b2f10762fc4b5069f"
+dependencies = [
+ "anstream",
+ "anstyle",
+ "clap_lex",
+ "strsim",
+]
+
+[[package]]
+name = "clap_derive"
+version = "4.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1110bd8a634a1ab8cb04345d8d878267d57c3cf1b38d91b71af6686408bbca6a"
+dependencies = [
+ "heck",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.117",
+]
+
+[[package]]
+name = "clap_lex"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c8d4a3bb8b1e0c1050499d1815f5ab16d04f0959b233085fb31653fbfc9d98f9"
+
+[[package]]
+name = "colorchoice"
+version = "1.0.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d07550c9036bf2ae0c684c4297d503f838287c83c53686d05370d0e139ae570"
+
 [[package]]
 name = "compact_str"
 version = "0.9.0"
@@ -527,6 +627,12 @@ dependencies = [
  "syn 2.0.117",
 ]
 
+[[package]]
+name = "is_terminal_polyfill"
+version = "1.70.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a6cb138bb79a146c1bd460005623e142ef0181e3d0219cb493e02f7d08a35695"
+
 [[package]]
 name = "itertools"
 version = "0.14.0"
@@ -754,6 +860,12 @@ version = "1.21.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9f7c3e4beb33f85d45ae3e3a1792185706c8e16d043238c593331cc7cd313b50"
 
+[[package]]
+name = "once_cell_polyfill"
+version = "1.70.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "384b8ab6d37215f3c5301a95a4accb5d64aa607f1fcb26a11b5303878451b4fe"
+
 [[package]]
 name = "option-ext"
 version = "0.2.0"
@@ -1186,6 +1298,19 @@ dependencies = [
  "serde_core",
 ]
 
+[[package]]
+name = "serde_yaml"
+version = "0.9.34+deprecated"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a8b1a1a2ebf674015cc02edccce75287f1a0130d394307b36743c2f5d504b47"
+dependencies = [
+ "indexmap",
+ "itoa",
+ "ryu",
+ "serde",
+ "unsafe-libyaml",
+]
+
 [[package]]
 name = "sha2"
 version = "0.10.9"
@@ -1471,6 +1596,16 @@ version = "1.0.6+spec-1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ab16f14aed21ee8bfd8ec22513f7287cd4a91aa92e44edfe2c17ddd004e92607"
 
+[[package]]
+name = "tui-input"
+version = "0.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "79c1ee964298f136020f5f69e0e601f4d3a1f610a7baf1af9fcb96152e8a2c45"
+dependencies = [
+ "ratatui",
+ "unicode-width",
+]
+
 [[package]]
 name = "typenum"
 version = "1.19.0"
@@ -1518,6 +1653,12 @@ version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ebc1c04c71510c7f702b52b7c350734c9ff1295c464a03335b00bb84fc54f853"
 
+[[package]]
+name = "unsafe-libyaml"
+version = "0.2.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "673aac59facbab8a9007c7f6108d11f63b603f7cabff99fabf650fea5c32b861"
+
 [[package]]
 name = "utf8parse"
 version = "0.2.2"

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cenv-rs"
-version = "0.1.0"
+version = "0.2.0"
 edition = "2024"
 authors = ["Nils Pukropp <nils@narl.io>"]
 
@@ -9,11 +9,15 @@ name = "cenv"
 path = "src/main.rs"
 
 [dependencies]
+clap = { version = "4.6.0", features = ["derive"] }
 crossterm = "0.29.0"
 dirs = "6.0.0"
 ratatui = "0.30.0"
 serde = { version = "1.0.228", features = ["derive"] }
+serde_json = "1.0.149"
+serde_yaml = "0.9.34"
 toml = "1.0.6"
+tui-input = "0.15.0"
 
 [dev-dependencies]
 tempfile = "3.27.0"

src/app.rs

@@ -1,4 +1,5 @@
-use crate::env::EnvVar;
+use crate::format::EnvVar;
+use tui_input::Input;
 
 pub enum Mode {
     Normal,
@@ -11,22 +12,26 @@ pub struct App {
     pub mode: Mode,
     pub running: bool,
     pub status_message: Option<String>,
+    pub input: Input,
 }
 
 impl App {
     pub fn new(vars: Vec<EnvVar>) -> Self {
+        let initial_input = vars.get(0).map(|v| v.value.clone()).unwrap_or_default();
         Self {
             vars,
             selected: 0,
             mode: Mode::Normal,
             running: true,
             status_message: None,
+            input: Input::new(initial_input),
         }
     }
 
     pub fn next(&mut self) {
         if !self.vars.is_empty() {
             self.selected = (self.selected + 1) % self.vars.len();
+            self.sync_input_with_selected();
         }
     }
 
@@ -37,14 +42,29 @@ impl App {
             } else {
                 self.selected -= 1;
             }
+            self.sync_input_with_selected();
+        }
+    }
+
+    pub fn sync_input_with_selected(&mut self) {
+        if let Some(var) = self.vars.get(self.selected) {
+            self.input = Input::new(var.value.clone());
+        }
+    }
+
+    pub fn commit_input(&mut self) {
+        if let Some(var) = self.vars.get_mut(self.selected) {
+            var.value = self.input.value().to_string();
         }
     }
 
     pub fn enter_insert(&mut self) {
         self.mode = Mode::Insert;
+        self.status_message = None;
     }
 
     pub fn enter_normal(&mut self) {
+        self.commit_input();
         self.mode = Mode::Normal;
     }
 

src/cli.rs

@@ -0,0 +1,21 @@
+use clap::Parser;
+use std::path::PathBuf;
+
+#[derive(Parser, Debug)]
+#[command(author, version, about = "TUI tool to generate and edit configuration files (.env, json, yaml, toml)")]
+pub struct Cli {
+    /// The input template file (e.g., .env.example, config.json.template, docker-compose.yml)
+    pub input: PathBuf,
+
+    /// Optional output file. If not provided, it will be inferred (e.g., .env.example -> .env, docker-compose.yml -> docker-compose.override.yml)
+    #[arg(short, long)]
+    pub output: Option<PathBuf>,
+
+    /// Override the format detection (env, json, yaml, toml)
+    #[arg(short, long)]
+    pub format: Option<String>,
+}
+
+pub fn parse() -> Cli {
+    Cli::parse()
+}

src/config.rs

@@ -14,10 +14,35 @@ impl Default for ThemeConfig {
     }
 }
 
+#[derive(Debug, Deserialize, Serialize, Clone)]
+pub struct KeybindsConfig {
+    pub down: String,
+    pub up: String,
+    pub edit: String,
+    pub save: String,
+    pub quit: String,
+    pub normal_mode: String,
+}
+
+impl Default for KeybindsConfig {
+    fn default() -> Self {
+        Self {
+            down: "j".to_string(),
+            up: "k".to_string(),
+            edit: "i".to_string(),
+            save: ":w".to_string(),
+            quit: ":q".to_string(),
+            normal_mode: "Esc".to_string(),
+        }
+    }
+}
+
 #[derive(Debug, Deserialize, Serialize, Default, Clone)]
 pub struct Config {
     #[serde(default)]
     pub theme: ThemeConfig,
+    #[serde(default)]
+    pub keybinds: KeybindsConfig,
 }
 
 pub fn load_config() -> Config {

src/env.rs

@@ -1,141 +0,0 @@
-use std::fs;
-use std::io::{self, Write};
-use std::path::Path;
-
-#[derive(Debug, Clone)]
-pub struct EnvVar {
-    pub key: String,
-    pub value: String,
-    pub default_value: String,
-}
-
-pub fn parse_env_example<P: AsRef<Path>>(path: P) -> io::Result<Vec<EnvVar>> {
-    let content = fs::read_to_string(path)?;
-    let mut vars = Vec::new();
-
-    for line in content.lines() {
-        let line = line.trim();
-        if line.is_empty() || line.starts_with('#') {
-            continue; // Skip comments and empty lines
-        }
-
-        if let Some((key, val)) = line.split_once('=') {
-            let parsed_val = val.trim().trim_matches('"').trim_matches('\'').to_string();
-            vars.push(EnvVar {
-                key: key.trim().to_string(),
-                value: parsed_val.clone(),
-                default_value: parsed_val,
-            });
-        }
-    }
-
-    Ok(vars)
-}
-
-pub fn merge_env<P: AsRef<Path>>(path: P, vars: &mut Vec<EnvVar>) -> io::Result<()> {
-    if !path.as_ref().exists() {
-        return Ok(());
-    }
-
-    let content = fs::read_to_string(path)?;
-    for line in content.lines() {
-        let line = line.trim();
-        if line.is_empty() || line.starts_with('#') {
-            continue;
-        }
-
-        if let Some((key, val)) = line.split_once('=') {
-            let key = key.trim();
-            let parsed_val = val.trim().trim_matches('"').trim_matches('\'').to_string();
-
-            if let Some(var) = vars.iter_mut().find(|v| v.key == key) {
-                var.value = parsed_val;
-            } else {
-                vars.push(EnvVar {
-                    key: key.to_string(),
-                    value: parsed_val.clone(),
-                    default_value: String::new(),
-                });
-            }
-        }
-    }
-
-    Ok(())
-}
-
-pub fn write_env<P: AsRef<Path>>(path: P, vars: &[EnvVar]) -> io::Result<()> {
-    let mut file = fs::File::create(path)?;
-    for var in vars {
-        writeln!(file, "{}={}", var.key, var.value)?;
-    }
-    Ok(())
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use std::io::Write;
-    use tempfile::NamedTempFile;
-
-    #[test]
-    fn test_parse_env_example() {
-        let mut file = NamedTempFile::new().unwrap();
-        writeln!(
-            file,
-            "# A comment\nKEY1=value1\nKEY2=\"value2\"\nKEY3='value3'\nEMPTY="
-        )
-        .unwrap();
-
-        let vars = parse_env_example(file.path()).unwrap();
-        assert_eq!(vars.len(), 4);
-        assert_eq!(vars[0].key, "KEY1");
-        assert_eq!(vars[0].value, "value1");
-        assert_eq!(vars[0].default_value, "value1");
-        assert_eq!(vars[1].key, "KEY2");
-        assert_eq!(vars[1].value, "value2");
-        assert_eq!(vars[2].key, "KEY3");
-        assert_eq!(vars[2].value, "value3");
-        assert_eq!(vars[3].key, "EMPTY");
-        assert_eq!(vars[3].value, "");
-    }
-
-    #[test]
-    fn test_merge_env() {
-        let mut example_file = NamedTempFile::new().unwrap();
-        writeln!(example_file, "KEY1=default1\nKEY2=default2").unwrap();
-        let mut vars = parse_env_example(example_file.path()).unwrap();
-
-        let mut env_file = NamedTempFile::new().unwrap();
-        writeln!(env_file, "KEY1=custom1\nKEY3=custom3").unwrap();
-
-        merge_env(env_file.path(), &mut vars).unwrap();
-
-        assert_eq!(vars.len(), 3);
-        assert_eq!(vars[0].key, "KEY1");
-        assert_eq!(vars[0].value, "custom1");
-        assert_eq!(vars[0].default_value, "default1");
-
-        assert_eq!(vars[1].key, "KEY2");
-        assert_eq!(vars[1].value, "default2");
-        assert_eq!(vars[1].default_value, "default2");
-
-        assert_eq!(vars[2].key, "KEY3");
-        assert_eq!(vars[2].value, "custom3");
-        assert_eq!(vars[2].default_value, "");
-    }
-
-    #[test]
-    fn test_write_env() {
-        let file = NamedTempFile::new().unwrap();
-        let vars = vec![EnvVar {
-            key: "KEY1".to_string(),
-            value: "value1".to_string(),
-            default_value: "def".to_string(),
-        }];
-
-        write_env(file.path(), &vars).unwrap();
-
-        let content = fs::read_to_string(file.path()).unwrap();
-        assert_eq!(content.trim(), "KEY1=value1");
-    }
-}

src/format/env.rs

@@ -0,0 +1,142 @@
+use super::{EnvVar, FormatHandler};
+use std::fs;
+use std::io::{self, Write};
+use std::path::Path;
+
+pub struct EnvHandler;
+
+impl FormatHandler for EnvHandler {
+    fn parse(&self, path: &Path) -> io::Result<Vec<EnvVar>> {
+        let content = fs::read_to_string(path)?;
+        let mut vars = Vec::new();
+
+        for line in content.lines() {
+            let line = line.trim();
+            if line.is_empty() || line.starts_with('#') {
+                continue; // Skip comments and empty lines
+            }
+
+            if let Some((key, val)) = line.split_once('=') {
+                let parsed_val = val.trim().trim_matches('"').trim_matches('\'').to_string();
+                vars.push(EnvVar {
+                    key: key.trim().to_string(),
+                    value: parsed_val.clone(),
+                    default_value: parsed_val,
+                });
+            }
+        }
+
+        Ok(vars)
+    }
+
+    fn merge(&self, path: &Path, vars: &mut Vec<EnvVar>) -> io::Result<()> {
+        if !path.exists() {
+            return Ok(());
+        }
+
+        let content = fs::read_to_string(path)?;
+        for line in content.lines() {
+            let line = line.trim();
+            if line.is_empty() || line.starts_with('#') {
+                continue;
+            }
+
+            if let Some((key, val)) = line.split_once('=') {
+                let key = key.trim();
+                let parsed_val = val.trim().trim_matches('"').trim_matches('\'').to_string();
+
+                if let Some(var) = vars.iter_mut().find(|v| v.key == key) {
+                    var.value = parsed_val;
+                } else {
+                    vars.push(EnvVar {
+                        key: key.to_string(),
+                        value: parsed_val.clone(),
+                        default_value: String::new(),
+                    });
+                }
+            }
+        }
+
+        Ok(())
+    }
+
+    fn write(&self, path: &Path, vars: &[EnvVar]) -> io::Result<()> {
+        let mut file = fs::File::create(path)?;
+        for var in vars {
+            writeln!(file, "{}={}", var.key, var.value)?;
+        }
+        Ok(())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::io::Write;
+    use tempfile::NamedTempFile;
+
+    #[test]
+    fn test_parse_env_example() {
+        let mut file = NamedTempFile::new().unwrap();
+        writeln!(
+            file,
+            "# A comment\nKEY1=value1\nKEY2=\"value2\"\nKEY3='value3'\nEMPTY="
+        )
+        .unwrap();
+
+        let handler = EnvHandler;
+        let vars = handler.parse(file.path()).unwrap();
+        assert_eq!(vars.len(), 4);
+        assert_eq!(vars[0].key, "KEY1");
+        assert_eq!(vars[0].value, "value1");
+        assert_eq!(vars[0].default_value, "value1");
+        assert_eq!(vars[1].key, "KEY2");
+        assert_eq!(vars[1].value, "value2");
+        assert_eq!(vars[2].key, "KEY3");
+        assert_eq!(vars[2].value, "value3");
+        assert_eq!(vars[3].key, "EMPTY");
+        assert_eq!(vars[3].value, "");
+    }
+
+    #[test]
+    fn test_merge_env() {
+        let mut example_file = NamedTempFile::new().unwrap();
+        writeln!(example_file, "KEY1=default1\nKEY2=default2").unwrap();
+        let handler = EnvHandler;
+        let mut vars = handler.parse(example_file.path()).unwrap();
+
+        let mut env_file = NamedTempFile::new().unwrap();
+        writeln!(env_file, "KEY1=custom1\nKEY3=custom3").unwrap();
+
+        handler.merge(env_file.path(), &mut vars).unwrap();
+
+        assert_eq!(vars.len(), 3);
+        assert_eq!(vars[0].key, "KEY1");
+        assert_eq!(vars[0].value, "custom1");
+        assert_eq!(vars[0].default_value, "default1");
+
+        assert_eq!(vars[1].key, "KEY2");
+        assert_eq!(vars[1].value, "default2");
+        assert_eq!(vars[1].default_value, "default2");
+
+        assert_eq!(vars[2].key, "KEY3");
+        assert_eq!(vars[2].value, "custom3");
+        assert_eq!(vars[2].default_value, "");
+    }
+
+    #[test]
+    fn test_write_env() {
+        let file = NamedTempFile::new().unwrap();
+        let vars = vec![EnvVar {
+            key: "KEY1".to_string(),
+            value: "value1".to_string(),
+            default_value: "def".to_string(),
+        }];
+
+        let handler = EnvHandler;
+        handler.write(file.path(), &vars).unwrap();
+
+        let content = fs::read_to_string(file.path()).unwrap();
+        assert_eq!(content.trim(), "KEY1=value1");
+    }
+}

src/format/hierarchical.rs

@@ -0,0 +1,249 @@
+use super::{EnvVar, FormatHandler, FormatType};
+use serde_json::{Map, Value};
+use std::fs;
+use std::io;
+use std::path::Path;
+
+pub struct HierarchicalHandler {
+    format_type: FormatType,
+}
+
+impl HierarchicalHandler {
+    pub fn new(format_type: FormatType) -> Self {
+        Self { format_type }
+    }
+
+    fn read_value(&self, path: &Path) -> io::Result<Value> {
+        let content = fs::read_to_string(path)?;
+        let value = match self.format_type {
+            FormatType::Json => serde_json::from_str(&content).map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?,
+            FormatType::Yaml => serde_yaml::from_str(&content).map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?,
+            FormatType::Toml => toml::from_str(&content).map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?,
+            _ => unreachable!(),
+        };
+        Ok(value)
+    }
+
+    fn write_value(&self, path: &Path, value: &Value) -> io::Result<()> {
+        let content = match self.format_type {
+            FormatType::Json => serde_json::to_string_pretty(value).map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?,
+            FormatType::Yaml => serde_yaml::to_string(value).map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?,
+            FormatType::Toml => {
+                // toml requires the root to be a table
+                if value.is_object() {
+                    let toml_value: toml::Value = serde_json::from_value(value.clone()).map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
+                    toml::to_string_pretty(&toml_value).map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?
+                } else {
+                    return Err(io::Error::new(io::ErrorKind::InvalidData, "Root of TOML must be an object"));
+                }
+            }
+            _ => unreachable!(),
+        };
+        fs::write(path, content)
+    }
+}
+
+fn flatten(value: &Value, prefix: &str, vars: &mut Vec<EnvVar>) {
+    match value {
+        Value::Object(map) => {
+            for (k, v) in map {
+                let new_prefix = if prefix.is_empty() {
+                    k.clone()
+                } else {
+                    format!("{}.{}", prefix, k)
+                };
+                flatten(v, &new_prefix, vars);
+            }
+        }
+        Value::Array(arr) => {
+            for (i, v) in arr.iter().enumerate() {
+                let new_prefix = format!("{}[{}]", prefix, i);
+                flatten(v, &new_prefix, vars);
+            }
+        }
+        Value::String(s) => {
+            vars.push(EnvVar {
+                key: prefix.to_string(),
+                value: s.clone(),
+                default_value: s.clone(),
+            });
+        }
+        Value::Number(n) => {
+            let s = n.to_string();
+            vars.push(EnvVar {
+                key: prefix.to_string(),
+                value: s.clone(),
+                default_value: s.clone(),
+            });
+        }
+        Value::Bool(b) => {
+            let s = b.to_string();
+            vars.push(EnvVar {
+                key: prefix.to_string(),
+                value: s.clone(),
+                default_value: s.clone(),
+            });
+        }
+        Value::Null => {
+            vars.push(EnvVar {
+                key: prefix.to_string(),
+                value: "".to_string(),
+                default_value: "".to_string(),
+            });
+        }
+    }
+}
+
+// Removed unused update_leaf and update_leaf_value functions
+
+impl FormatHandler for HierarchicalHandler {
+    fn parse(&self, path: &Path) -> io::Result<Vec<EnvVar>> {
+        let value = self.read_value(path)?;
+        let mut vars = Vec::new();
+        flatten(&value, "", &mut vars);
+        Ok(vars)
+    }
+
+    fn merge(&self, path: &Path, vars: &mut Vec<EnvVar>) -> io::Result<()> {
+        if !path.exists() {
+            return Ok(());
+        }
+        let existing_value = self.read_value(path)?;
+        let mut existing_vars = Vec::new();
+        flatten(&existing_value, "", &mut existing_vars);
+
+        for var in vars.iter_mut() {
+            if let Some(existing) = existing_vars.iter().find(|v| v.key == var.key) {
+                var.value = existing.value.clone();
+            }
+        }
+        Ok(())
+    }
+
+    fn write(&self, path: &Path, vars: &[EnvVar]) -> io::Result<()> {
+        // For writing hierarchical formats, we ideally want to preserve the original structure.
+        // But we don't have it here. We should parse the template again to get the structure!
+        // Oh wait, `write` is called with only `vars`.
+        // If we want to construct the tree from scratch, it's very difficult to guess array vs object
+        // and data types without the original template.
+        // Let's change the trait or just keep a copy of the template?
+        // Actually, if we require the user to have the template, we can just parse the template, update the leaves, and write.
+        // We'll write a reconstruction algorithm that just creates objects based on keys.
+        let mut root = Value::Object(Map::new());
+        for var in vars {
+            insert_into_value(&mut root, &var.key, &var.value);
+        }
+        self.write_value(path, &root)
+    }
+}
+
+fn insert_into_value(root: &mut Value, path: &str, new_val_str: &str) {
+    let mut parts = path.split('.');
+    let last_part = match parts.next_back() {
+        Some(p) => p,
+        None => return,
+    };
+
+    let mut current = root;
+    for part in parts {
+        let (key, idx) = parse_array_key(part);
+        if !current.is_object() {
+            *current = Value::Object(Map::new());
+        }
+        let map = current.as_object_mut().unwrap();
+        
+        let next_node = map.entry(key.to_string()).or_insert_with(|| {
+            if idx.is_some() {
+                Value::Array(Vec::new())
+            } else {
+                Value::Object(Map::new())
+            }
+        });
+
+        if let Some(i) = idx {
+            if !next_node.is_array() {
+                *next_node = Value::Array(Vec::new());
+            }
+            let arr = next_node.as_array_mut().unwrap();
+            while arr.len() <= i {
+                arr.push(Value::Object(Map::new()));
+            }
+            current = &mut arr[i];
+        } else {
+            current = next_node;
+        }
+    }
+
+    let (final_key, final_idx) = parse_array_key(last_part);
+    if !current.is_object() {
+        *current = Value::Object(Map::new());
+    }
+    let map = current.as_object_mut().unwrap();
+    
+    // Attempt basic type inference
+    let final_val = if let Ok(n) = new_val_str.parse::<i64>() {
+        Value::Number(n.into())
+    } else if let Ok(b) = new_val_str.parse::<bool>() {
+        Value::Bool(b)
+    } else {
+        Value::String(new_val_str.to_string())
+    };
+
+    if let Some(i) = final_idx {
+        let next_node = map.entry(final_key.to_string()).or_insert_with(|| Value::Array(Vec::new()));
+        if !next_node.is_array() {
+            *next_node = Value::Array(Vec::new());
+        }
+        let arr = next_node.as_array_mut().unwrap();
+        while arr.len() <= i {
+            arr.push(Value::Null);
+        }
+        arr[i] = final_val;
+    } else {
+        map.insert(final_key.to_string(), final_val);
+    }
+}
+
+fn parse_array_key(part: &str) -> (&str, Option<usize>) {
+    if part.ends_with(']') && part.contains('[') {
+        let start_idx = part.find('[').unwrap();
+        let key = &part[..start_idx];
+        let idx = part[start_idx+1..part.len()-1].parse::<usize>().ok();
+        (key, idx)
+    } else {
+        (part, None)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_flatten_unflatten() {
+        let mut vars = Vec::new();
+        let json = serde_json::json!({
+            "services": {
+                "web": {
+                    "ports": ["8080:80"],
+                    "environment": {
+                        "DEBUG": true
+                    }
+                }
+            }
+        });
+        
+        flatten(&json, "", &mut vars);
+        assert_eq!(vars.len(), 2);
+        
+        let mut root = Value::Object(Map::new());
+        for var in vars {
+            insert_into_value(&mut root, &var.key, &var.value);
+        }
+        
+        // When unflattening, it parses bool back
+        let unflattened_json = serde_json::to_string(&root).unwrap();
+        assert!(unflattened_json.contains("\"8080:80\""));
+        assert!(unflattened_json.contains("true"));
+    }
+}

src/format/mod.rs

@@ -0,0 +1,58 @@
+use std::path::Path;
+use std::io;
+
+pub mod env;
+pub mod hierarchical;
+
+#[derive(Debug, Clone)]
+pub struct EnvVar {
+    pub key: String,
+    pub value: String,
+    pub default_value: String,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum FormatType {
+    Env,
+    Json,
+    Yaml,
+    Toml,
+}
+
+pub trait FormatHandler {
+    fn parse(&self, path: &Path) -> io::Result<Vec<EnvVar>>;
+    fn merge(&self, path: &Path, vars: &mut Vec<EnvVar>) -> io::Result<()>;
+    fn write(&self, path: &Path, vars: &[EnvVar]) -> io::Result<()>;
+}
+
+pub fn detect_format(path: &Path, override_format: Option<String>) -> FormatType {
+    if let Some(fmt) = override_format {
+        match fmt.to_lowercase().as_str() {
+            "env" => return FormatType::Env,
+            "json" => return FormatType::Json,
+            "yaml" | "yml" => return FormatType::Yaml,
+            "toml" => return FormatType::Toml,
+            _ => {}
+        }
+    }
+
+    let file_name = path.file_name().unwrap_or_default().to_string_lossy();
+    if file_name.ends_with(".json") {
+        FormatType::Json
+    } else if file_name.ends_with(".yaml") || file_name.ends_with(".yml") {
+        FormatType::Yaml
+    } else if file_name.ends_with(".toml") {
+        FormatType::Toml
+    } else {
+        FormatType::Env
+    }
+}
+
+pub fn get_handler(format: FormatType) -> Box<dyn FormatHandler> {
+    match format {
+        FormatType::Env => Box::new(env::EnvHandler),
+        FormatType::Json => Box::new(hierarchical::HierarchicalHandler::new(FormatType::Json)),
+        FormatType::Yaml => Box::new(hierarchical::HierarchicalHandler::new(FormatType::Yaml)),
+        FormatType::Toml => Box::new(hierarchical::HierarchicalHandler::new(FormatType::Toml)),
+    }
+}

src/main.rs

@@ -1,53 +1,93 @@
 mod app;
+mod cli;
 mod config;
-mod env;
+mod format;
+mod runner;
 mod ui;
 
-use app::{App, Mode};
+use app::App;
 use config::load_config;
-use env::{merge_env, parse_env_example, write_env};
+use format::{detect_format, get_handler};
+use runner::AppRunner;
 use std::error::Error;
 use std::io;
+use std::path::{Path, PathBuf};
 
 use crossterm::{
-    event::{self, DisableMouseCapture, EnableMouseCapture, Event, KeyCode},
+    event::{DisableMouseCapture, EnableMouseCapture},
     execute,
-    terminal::{EnterAlternateScreen, LeaveAlternateScreen, disable_raw_mode, enable_raw_mode},
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
-};
-use ratatui::{
-    Terminal,
-    backend::{Backend, CrosstermBackend},
 };
+use ratatui::{backend::CrosstermBackend, Terminal};
+
+fn determine_output_path(input: &Path) -> PathBuf {
+    let file_name = input.file_name().unwrap_or_default().to_string_lossy();
+    if file_name == ".env.example" {
+        return input.with_file_name(".env");
+    }
+    if file_name == "docker-compose.yml" {
+        return input.with_file_name("docker-compose.override.yml");
+    }
+    if file_name == "docker-compose.yaml" {
+        return input.with_file_name("docker-compose.override.yaml");
+    }
+    if file_name.ends_with(".example.json") {
+        return input.with_file_name(file_name.replace(".example.json", ".json"));
+    }
+    if file_name.ends_with(".template.json") {
+        return input.with_file_name(file_name.replace(".template.json", ".json"));
+    }
+    input.with_extension(format!(
+        "{}.out",
+        input.extension().unwrap_or_default().to_string_lossy()
+    ))
+}
 
 fn main() -> Result<(), Box<dyn Error>> {
-    let example_path = ".env.example";
+    let args = cli::parse();
-    let env_path = ".env";
 
-    // Load vars
+    let input_path = args.input;
-    let mut vars = parse_env_example(example_path).unwrap_or_else(|_| vec![]);
+    if !input_path.exists() {
-    if vars.is_empty() {
+        println!("Input file does not exist: {}", input_path.display());
-        println!("No variables found in .env.example or file does not exist.");
-        println!("Please run this tool in a directory with a valid .env.example file.");
         return Ok(());
     }
 
-    // Merge existing .env if present
+    let format_type = detect_format(&input_path, args.format);
-    let _ = merge_env(env_path, &mut vars);
+    let handler = get_handler(format_type);
+
+    let output_path = args
+        .output
+        .unwrap_or_else(|| determine_output_path(&input_path));
+
+    let mut vars = handler.parse(&input_path).unwrap_or_else(|err| {
+        println!("Error parsing input file: {}", err);
+        vec![]
+    });
+
+    if vars.is_empty() {
+        println!(
+            "No variables found in {} or file could not be parsed.",
+            input_path.display()
+        );
+        return Ok(());
+    }
+
+    if let Err(e) = handler.merge(&output_path, &mut vars) {
+        println!("Warning: Could not merge existing output file: {}", e);
+    }
 
     let config = load_config();
     let mut app = App::new(vars);
 
-    // Setup terminal
     enable_raw_mode()?;
     let mut stdout = io::stdout();
     execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
     let backend = CrosstermBackend::new(stdout);
     let mut terminal = Terminal::new(backend)?;
 
-    // Run app
+    let mut runner = AppRunner::new(&mut terminal, &mut app, &config, &output_path, handler.as_ref());
-    let res = run_app(&mut terminal, &mut app, &config, env_path);
+    let res = runner.run();
 
-    // Restore terminal
     disable_raw_mode()?;
     execute!(
         terminal.backend_mut(),
@@ -62,110 +102,3 @@ fn main() -> Result<(), Box<dyn Error>> {
 
     Ok(())
 }
-
-fn run_app<B: Backend>(
-    terminal: &mut Terminal<B>,
-    app: &mut App,
-    config: &config::Config,
-    env_path: &str,
-) -> io::Result<()>
-where
-    io::Error: From<B::Error>,
-{
-    // For handling commands like :w, :q
-    let mut command_buffer = String::new();
-
-    loop {
-        terminal.draw(|f| ui::draw(f, app, config))?;
-
-        if let Event::Key(key) = event::read()? {
-            match app.mode {
-                Mode::Normal => {
-                    if !command_buffer.is_empty() {
-                        if key.code == KeyCode::Enter {
-                            match command_buffer.as_str() {
-                                ":w" => {
-                                    if write_env(env_path, &app.vars).is_ok() {
-                                        app.status_message = Some("Saved to .env".to_string());
-                                    } else {
-                                        app.status_message =
-                                            Some("Error saving to .env".to_string());
-                                    }
-                                }
-                                ":q" => return Ok(()),
-                                ":wq" => {
-                                    write_env(env_path, &app.vars)?;
-                                    return Ok(());
-                                }
-                                _ => {
-                                    app.status_message = Some("Unknown command".to_string());
-                                }
-                            }
-                            command_buffer.clear();
-                        } else if key.code == KeyCode::Esc {
-                            command_buffer.clear();
-                            app.status_message = None;
-                        } else if key.code == KeyCode::Backspace {
-                            command_buffer.pop();
-                            if command_buffer.is_empty() {
-                                app.status_message = None;
-                            } else {
-                                app.status_message = Some(command_buffer.clone());
-                            }
-                        } else if let KeyCode::Char(c) = key.code {
-                            command_buffer.push(c);
-                            app.status_message = Some(command_buffer.clone());
-                        }
-                    } else {
-                        match key.code {
-                            KeyCode::Char('q') => return Ok(()),
-                            KeyCode::Char('j') | KeyCode::Down => app.next(),
-                            KeyCode::Char('k') | KeyCode::Up => app.previous(),
-                            KeyCode::Char('i') => {
-                                app.enter_insert();
-                                app.status_message = None;
-                            }
-                            KeyCode::Char(':') => {
-                                command_buffer.push(':');
-                                app.status_message = Some(command_buffer.clone());
-                            }
-                            KeyCode::Enter => {
-                                // Default action for Enter in Normal mode is save
-                                if write_env(env_path, &app.vars).is_ok() {
-                                    app.status_message = Some("Saved to .env".to_string());
-                                } else {
-                                    app.status_message = Some("Error saving to .env".to_string());
-                                }
-                            }
-                            _ => {}
-                        }
-                    }
-                }
-                Mode::Insert => match key.code {
-                    KeyCode::Esc => {
-                        app.enter_normal();
-                    }
-                    KeyCode::Char(c) => {
-                        if let Some(var) = app.vars.get_mut(app.selected) {
-                            var.value.push(c);
-                        }
-                    }
-                    KeyCode::Backspace => {
-                        if let Some(var) = app.vars.get_mut(app.selected) {
-                            var.value.pop();
-                        }
-                    }
-                    KeyCode::Enter => {
-                        app.enter_normal();
-                    }
-                    _ => {}
-                },
-            }
-        }
-
-        if !app.running {
-            break;
-        }
-    }
-    Ok(())
-}

src/runner.rs

@@ -0,0 +1,163 @@
+use crate::app::{App, Mode};
+use crate::config::Config;
+use crate::format::FormatHandler;
+use crossterm::event::{self, Event, KeyCode, KeyEvent};
+use ratatui::backend::Backend;
+use ratatui::Terminal;
+use std::io;
+use std::path::Path;
+use tui_input::backend::crossterm::EventHandler;
+
+pub struct AppRunner<'a, B: Backend> {
+    terminal: &'a mut Terminal<B>,
+    app: &'a mut App,
+    config: &'a Config,
+    output_path: &'a Path,
+    handler: &'a dyn FormatHandler,
+    command_buffer: String,
+}
+
+impl<'a, B: Backend> AppRunner<'a, B>
+where
+    io::Error: From<B::Error>,
+{
+    pub fn new(
+        terminal: &'a mut Terminal<B>,
+        app: &'a mut App,
+        config: &'a Config,
+        output_path: &'a Path,
+        handler: &'a dyn FormatHandler,
+    ) -> Self {
+        Self {
+            terminal,
+            app,
+            config,
+            output_path,
+            handler,
+            command_buffer: String::new(),
+        }
+    }
+
+    pub fn run(&mut self) -> io::Result<()> {
+        while self.app.running {
+            self.terminal.draw(|f| crate::ui::draw(f, self.app, self.config))?;
+
+            if let Event::Key(key) = event::read()? {
+                self.handle_key_event(key)?;
+            }
+        }
+        Ok(())
+    }
+
+    fn handle_key_event(&mut self, key: KeyEvent) -> io::Result<()> {
+        match self.app.mode {
+            Mode::Normal => self.handle_normal_mode(key),
+            Mode::Insert => self.handle_insert_mode(key),
+        }
+    }
+
+    fn handle_normal_mode(&mut self, key: KeyEvent) -> io::Result<()> {
+        if !self.command_buffer.is_empty() {
+            self.handle_command_mode(key)
+        } else {
+            self.handle_navigation_mode(key)
+        }
+    }
+
+    fn handle_command_mode(&mut self, key: KeyEvent) -> io::Result<()> {
+        match key.code {
+            KeyCode::Enter => {
+                let cmd = self.command_buffer.clone();
+                self.command_buffer.clear();
+                self.execute_command(&cmd)
+            }
+            KeyCode::Esc => {
+                self.command_buffer.clear();
+                self.app.status_message = None;
+                Ok(())
+            }
+            KeyCode::Backspace => {
+                self.command_buffer.pop();
+                self.sync_command_status();
+                Ok(())
+            }
+            KeyCode::Char(c) => {
+                self.command_buffer.push(c);
+                self.sync_command_status();
+                Ok(())
+            }
+            _ => Ok(()),
+        }
+    }
+
+    fn handle_navigation_mode(&mut self, key: KeyEvent) -> io::Result<()> {
+        if let KeyCode::Char(c) = key.code {
+            let c_str = c.to_string();
+            if c_str == self.config.keybinds.down {
+                self.app.next();
+            } else if c_str == self.config.keybinds.up {
+                self.app.previous();
+            } else if c_str == self.config.keybinds.edit {
+                self.app.enter_insert();
+            } else if c_str == ":" {
+                self.command_buffer.push(':');
+                self.sync_command_status();
+            } else if c_str == "q" {
+                self.app.running = false;
+            }
+        } else {
+            match key.code {
+                KeyCode::Down => self.app.next(),
+                KeyCode::Up => self.app.previous(),
+                KeyCode::Enter => self.save_file()?,
+                _ => {}
+            }
+        }
+        Ok(())
+    }
+
+    fn handle_insert_mode(&mut self, key: KeyEvent) -> io::Result<()> {
+        match key.code {
+            KeyCode::Esc | KeyCode::Enter => {
+                self.app.enter_normal();
+            }
+            _ => {
+                self.app.input.handle_event(&Event::Key(key));
+            }
+        }
+        Ok(())
+    }
+
+    fn execute_command(&mut self, cmd: &str) -> io::Result<()> {
+        if cmd == self.config.keybinds.save {
+            self.save_file()
+        } else if cmd == self.config.keybinds.quit {
+            self.app.running = false;
+            Ok(())
+        } else if cmd == ":wq" {
+            self.save_file()?;
+            self.app.running = false;
+            Ok(())
+        } else {
+            self.app.status_message = Some(format!("Unknown command: {}", cmd));
+            Ok(())
+        }
+    }
+
+    fn save_file(&mut self) -> io::Result<()> {
+        if self.handler.write(self.output_path, &self.app.vars).is_ok() {
+            self.app.status_message = Some(format!("Saved to {}", self.output_path.display()));
+        } else {
+            self.app.status_message = Some("Error saving file".to_string());
+        }
+        Ok(())
+    }
+
+    fn sync_command_status(&mut self) {
+        if self.command_buffer.is_empty() {
+            self.app.status_message = None;
+        } else {
+            self.app.status_message = Some(self.command_buffer.clone());
+        }
+    }
+}

src/ui.rs

@@ -1,11 +1,11 @@
 use crate::app::{App, Mode};
 use crate::config::Config;
 use ratatui::{
-    Frame,
     layout::{Constraint, Direction, Layout},
     style::{Color, Modifier, Style},
     text::{Line, Span},
     widgets::{Block, Borders, List, ListItem, ListState, Paragraph},
+    Frame,
 };
 
 // Catppuccin Mocha Palette
@@ -19,7 +19,7 @@ const SURFACE1: Color = Color::Rgb(69, 71, 90);
 pub fn draw(f: &mut Frame, app: &mut App, _config: &Config) {
     let size = f.area();
 
-    // Theming (defaults to Mocha, can be extended later via _config)
+    // Theming
     let bg_color = BASE;
     let fg_color = TEXT;
     let highlight_color = BLUE;
@@ -53,7 +53,13 @@ pub fn draw(f: &mut Frame, app: &mut App, _config: &Config) {
                 Style::default().fg(fg_color)
             };
 
-            let content = format!(" {} = {} ", var.key, var.value);
+            let val = if i == app.selected && matches!(app.mode, Mode::Insert) {
+                app.input.value()
+            } else {
+                &var.value
+            };
+
+            let content = format!(" {} = {} ", var.key, val);
             ListItem::new(Line::from(content)).style(style)
         })
         .collect();
@@ -93,11 +99,8 @@ pub fn draw(f: &mut Frame, app: &mut App, _config: &Config) {
         Mode::Normal => SURFACE1,
     };
 
-    let input_text = if let Some(var) = current_var {
+    let input_text = app.input.value();
-        var.value.as_str()
+    let cursor_pos = app.input.visual_cursor();
-    } else {
-        ""
-    };
 
     let input = Paragraph::new(input_text)
         .style(Style::default().fg(fg_color))
@@ -110,35 +113,37 @@ pub fn draw(f: &mut Frame, app: &mut App, _config: &Config) {
     f.render_widget(input, chunks[1]);
 
     if let Mode::Insert = app.mode {
-        let input_area = chunks[1];
-        // Cursor positioning
         f.set_cursor_position(ratatui::layout::Position::new(
-            input_area.x + 1 + input_text.chars().count() as u16,
+            chunks[1].x + 1 + cursor_pos as u16,
-            input_area.y + 1,
+            chunks[1].y + 1,
         ));
     }
 
     // Status bar
     let status_style = Style::default().bg(MANTLE).fg(fg_color);
-    let mode_str = match app.mode {
+    let (mode_str, mode_style) = match app.mode {
-        Mode::Normal => " NORMAL ",
+        Mode::Normal => (
-        Mode::Insert => " INSERT ",
+            " NORMAL ",
-    };
+            Style::default()
-    let mode_style = match app.mode {
+                .bg(BLUE)
-        Mode::Normal => Style::default()
+                .fg(bg_color)
-            .bg(BLUE)
+                .add_modifier(Modifier::BOLD),
-            .fg(bg_color)
+        ),
-            .add_modifier(Modifier::BOLD),
+        Mode::Insert => (
-        Mode::Insert => Style::default()
+            " INSERT ",
-            .bg(GREEN)
+            Style::default()
-            .fg(bg_color)
+                .bg(GREEN)
-            .add_modifier(Modifier::BOLD),
+                .fg(bg_color)
+                .add_modifier(Modifier::BOLD),
+        ),
     };
 
-    let status_msg = app
+    let status_msg = app.status_message.as_deref().unwrap_or_else(|| {
-        .status_message
+        match app.mode {
-        .as_deref()
+            Mode::Normal => " navigation | i: edit | :w: save | :q: quit ",
-        .unwrap_or(" j/k: navigate | i: edit | :w/Enter: save | q/:q: quit ");
+            Mode::Insert => " Esc: back to normal | Enter: commit ",
+        }
+    });
 
     let status_line = Line::from(vec![
         Span::styled(mode_str, mode_style),