# Contributing Guide (Java Style)

This project follows a strict, C/C++-style Java formatting rule set. The goal is to preserve intent, control flow clarity, and fast mental parsing. Please follow these rules for any Java changes.

If a tool or formatter fights these rules, the tool is wrong.

## Core Philosophy

- Java is written as if it were C/C++.
- Formatting must never change perceived control flow.
- Readability means fast, correct parsing in your head.
- Tools adapt to the codebase, not the other way around.

## Indentation & Whitespace

- Indentation: 4 spaces.
- No tabs.
- Avoid excessive vertical whitespace.
- Blank lines only when they add logical separation.

✅ Good:
```java
int sum(int a, int b) {
    int r = a + b;
    return r;
}
```

❌ Bad:
```java
int sum(int a, int b)

{

    int r = a + b;

    return r;
}
```

## Braces

- Braces are always required.
- Opening brace stays on the same line.
- Never rely on implicit scopes.

✅ Good:
```java
if (value == null) {
    return;
}
```

❌ Bad:
```java
if (value == null)
{
    return;
}
```

## Imports (Strict Rules)

### Never use fully-qualified class names inline

❌ Forbidden:
```java
net.minecraft.util.math.BlockPos pos = new net.minecraft.util.math.BlockPos(0, 0, 0);
```

✅ Required:
```java
import net.minecraft.util.math.BlockPos;

BlockPos pos = new BlockPos(0, 0, 0);
```

### Import grouping and ordering

1) Imports from external/other packages first.
2) Blank line.
3) Imports from this project (net.Chipperfluff.*) next.

Inside each block, order by:
1) Classes
2) Functions (static method imports)
3) Variables/constants (static field imports)
4) Enums

If there are no project imports, do not add a blank line.

## Method Signatures

- Method signatures must stay on one line.
- Do not break parameters across multiple lines.
- Long lines are acceptable; ambiguity is not.

✅ Good:
```java
void processUser(User user, int flags, boolean force, long timeout) {
    ...
}
```

❌ Bad:
```java
void processUser(
    User user,
    int flags,
    boolean force,
    long timeout
) {
    ...
}
```

## Function Calls & Argument Layout

### Default rule
- Single-line calls are preferred.
- Flat calls stay flat.
- Length alone is not a reason to wrap.

✅ Good:
```java
Color color = user.getProfile().getSettings().getTheme().getPrimaryColor();
```

### Multiline calls are allowed only when:
- The call is structural or declarative.
- Each argument is conceptually distinct.
- Nesting would otherwise hide meaning.

✅ Good (structural/declarative):
```java
BiomeModifications.addFeature(
    BiomeSelectors.foundInOverworld(),
    GenerationStep.Feature.UNDERGROUND_ORES,
    RegistryKey.of(
        RegistryKeys.PLACED_FEATURE,
        new Identifier("chipi", "chipper_ore")
    )
);
```

❌ Bad (no semantic gain):
```java
doThing(
    a,
    b,
    c
);
```

## Chained Calls

- Flat chains stay on one line.
- Long or builder-style chains may be split vertically.
- Each chained step gets its own line.

✅ Good:
```java
builder
    .withColor(theme.getPrimaryColor())
    .withSize(32)
    .enableShadow()
    .build();
```

❌ Bad:
```java
builder.withColor(
    theme.getPrimaryColor()
).withSize(
    32
).enableShadow().build();
```

## Control Flow & Returns

- Early returns are encouraged.
- Avoid artificial nesting.
- Single-exit functions are not required.

✅ Good:
```java
void handle(User user) {
    if (user == null) return;
    if (!user.isActive()) return;

    process(user);
}
```

❌ Bad:
```java
void handle(User user) {
    if (user != null) {
        if (user.isActive()) {
            process(user);
        }
    }
}
```

## One-Liners

- One-liners allowed for simple guard clauses.
- No complex logic on one line.

✅ Allowed:
```java
if (value == null) return;
```

❌ Not allowed:
```java
if (a == b && c != d && flag && check()) doThing();
```

## Null Handling

- null is a valid, intentional state.
- Do not over-engineer around it.
- Prefer clarity over defensive clutter.

✅ Good:
```java
User user = findUser(id);
if (user == null) return;
```

## Logging & Debug Output

- Logging must be short and readable.
- Prefer System.out.println for quick diagnostics.
- Verbose logging only when justified.

✅ Good:
```java
System.out.println("Loaded structure: " + id);
```

## Autoformatters & Linters

Autoformatters must not:

- Break method signatures.
- Move braces to new lines.
- Introduce unwanted trailing newlines.
- Rewrap stable code repeatedly.

If a formatter fights these rules: disable or reconfigure it.

## Empty Methods

Empty methods or constructors must be written on one line:

```java
public static void register() {}
```

## Summary (Non-Negotiable)

- Java written with C/C++ structure.
- Compact signatures, explicit layout.
- Imports always used (no fully-qualified inline types).
- Multiline formatting only when it adds meaning.
- Formatting reflects logic, not fashion.