# Phase 01 — Project Scaffold

## Goal
Create the complete Rust project skeleton with correct Cargo.toml, build system,
directory structure, and verify that the project compiles (empty/stub implementations).

## Prerequisites
- Rust toolchain installed (rustup, cargo)
- System dependencies installed (see docs/architecture.md — System Dependencies section)
- Verify with: `pkg-config --exists gtk4 libadwaita-1 && echo "OK"`

## Steps

### 1. Create project
```bash
cargo new --bin mangotune
cd mangotune
```

### 2. Create full directory structure
```bash
mkdir -p src/{config,system,launcher,integrations,ui/{pages,widgets}}
mkdir -p data/icons
```

### 3. Write Cargo.toml
Copy the exact dependency block from `docs/architecture.md` → Cargo.toml section.
Do not add or remove any dependencies without updating docs/architecture.md.

### 4. Write build.rs
```rust
// build.rs
fn main() {
    glib_build_tools::compile_schemas("data");
}
```

### 5. Create GSettings schema
File: `data/com.mangotune.MangoTune.gschema.xml`
```xml
<?xml version="1.0" encoding="UTF-8"?>
<schemalist>
  <schema id="com.mangotune.MangoTune" path="/com/mangotune/MangoTune/">
    <key name="last-config-path" type="s">
      <default>''</default>
      <summary>Last edited config file path</summary>
    </key>
    <key name="window-width" type="i">
      <default>1200</default>
      <summary>Window width</summary>
    </key>
    <key name="window-height" type="i">
      <default>780</default>
      <summary>Window height</summary>
    </key>
    <key name="active-page" type="s">
      <default>'performance'</default>
      <summary>Currently active sidebar page</summary>
    </key>
    <key name="show-raw-editor" type="b">
      <default>false</default>
      <summary>Whether raw editor tab is visible</summary>
    </key>
  </schema>
</schemalist>
```

### 6. Create .desktop file
File: `data/com.mangotune.MangoTune.desktop`
```ini
[Desktop Entry]
Name=MangoTune
Comment=MangoHud Overlay Configurator
Exec=mangotune
Icon=com.mangotune.MangoTune
Terminal=false
Type=Application
Categories=Settings;System;
Keywords=MangoHud;overlay;gaming;performance;
StartupNotify=true
StartupWMClass=mangotune
```

### 7. Create all source stub files
Each file listed in docs/architecture.md → Target Source Tree must be created
as a stub with correct module declarations and a `todo!()` placeholder where needed.

Required stub content for each module file:
```rust
// src/config/parser.rs
//! MangoHud config file parser and writer.
//! See: mangotune-plan/modules/config_parser.md for full spec.

pub struct Parser;

impl Parser {
    pub fn new() -> Self { todo!() }
}
```

### 8. Wire up main.rs
```rust
// src/main.rs
mod app;
mod config;
mod system;
mod launcher;
mod integrations;
mod ui;

fn main() {
    tracing_subscriber::fmt::init();
    let app = app::MangoTuneApp::new();
    std::process::exit(app.run());
}
```

### 9. Wire up app.rs stub
```rust
// src/app.rs
use gtk4::prelude::*;
use libadwaita::prelude::*;

pub struct MangoTuneApp {
    app: libadwaita::Application,
}

impl MangoTuneApp {
    pub fn new() -> Self {
        let app = libadwaita::Application::builder()
            .application_id("com.mangotune.MangoTune")
            .build();
        MangoTuneApp { app }
    }

    pub fn run(&self) -> i32 {
        self.app.run().into()
    }
}
```

### 10. Verify compilation
```bash
cargo check 2>&1
```
Must produce zero errors (warnings acceptable at this stage).

## Acceptance Criteria
- [ ] `cargo check` exits with code 0
- [ ] All directories from the target source tree exist
- [ ] All source stub files exist with correct module declarations
- [ ] `data/` contains gschema.xml and .desktop file
- [ ] `build.rs` compiles the schema without error
- [ ] No `.unwrap()` calls in non-stub code (stubs with `todo!()` are exempt)