# Task 01: Project Setup

**Phase**: 1 - Core (MVP)
**Priority**: Critical
**Estimated Time**: 30 minutes
**Dependencies**: None

## Objective

Set up the project structure with proper Emacs Lisp package conventions, including file headers, licensing, and build tooling.

## Prerequisites

- Emacs 27.1+ installed
- Elixir installed and in PATH
- Git repository initialized

## Steps

### Step 1: Create the main package file

Create `ob-elixir.el` with proper headers:

```elisp
;;; ob-elixir.el --- Org Babel functions for Elixir -*- lexical-binding: t; -*-

;; Copyright (C) 2024 Your Name

;; Author: Your Name <your.email@example.com>
;; URL: https://github.com/username/ob-elixir
;; Keywords: literate programming, reproducible research, elixir
;; Version: 0.1.0
;; Package-Requires: ((emacs "27.1") (org "9.4"))

;; This file is not part of GNU Emacs.

;; This program is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;;; Commentary:

;; Org Babel support for evaluating Elixir code blocks.
;;
;; Features:
;; - Execute Elixir code in org-mode source blocks
;; - Support for :results value and :results output
;; - Variable passing with :var header argument
;; - Mix project context support
;;
;; Usage:
;; Add (elixir . t) to `org-babel-load-languages':
;;
;;   (org-babel-do-load-languages
;;    'org-babel-load-languages
;;    '((elixir . t)))

;;; Code:

(require 'ob)
(require 'ob-eval)

(provide 'ob-elixir)
;;; ob-elixir.el ends here
```

### Step 2: Create the Eldev file for build tooling

Create `Eldev` file:

```elisp
; -*- mode: emacs-lisp; lexical-binding: t; -*-

(eldev-use-package-archive 'gnu)
(eldev-use-package-archive 'melpa)

;; Test dependencies
(eldev-add-extra-dependencies 'test 'ert)

;; Use ERT for testing
(setf eldev-test-framework 'ert)

;; Lint configuration
(setf eldev-lint-default '(elisp package))
```

### Step 3: Create test directory structure

```bash
mkdir -p test
```

Create `test/test-ob-elixir.el`:

```elisp
;;; test-ob-elixir.el --- Tests for ob-elixir -*- lexical-binding: t; -*-

;;; Commentary:

;; Test suite for ob-elixir package.

;;; Code:

(require 'ert)

;; Add parent directory to load path
(let ((dir (file-name-directory (or load-file-name buffer-file-name))))
  (add-to-list 'load-path (expand-file-name ".." dir)))

(require 'ob-elixir)

(ert-deftest ob-elixir-test-package-loads ()
  "Test that the package loads successfully."
  (should (featurep 'ob-elixir)))

(provide 'test-ob-elixir)
;;; test-ob-elixir.el ends here
```

### Step 4: Create Makefile

Create `Makefile`:

```makefile
EMACS ?= emacs
BATCH = $(EMACS) -Q -batch -L .

.PHONY: all compile test lint clean

all: compile test

compile:
	$(BATCH) -f batch-byte-compile ob-elixir.el

test:
	$(BATCH) -l ert -l test/test-ob-elixir.el \
		-f ert-run-tests-batch-and-exit

lint:
	$(BATCH) --eval "(require 'package)" \
		--eval "(package-initialize)" \
		--eval "(package-refresh-contents)" \
		--eval "(package-install 'package-lint)" \
		-l package-lint \
		-f package-lint-batch-and-exit ob-elixir.el

clean:
	rm -f *.elc test/*.elc
```

### Step 5: Create .gitignore

Create `.gitignore`:

```
# Byte-compiled files
*.elc

# Eldev
.eldev/
Eldev-local

# Package archives
/packages/

# Test artifacts
/test/tmp/

# Editor
*~
\#*\#
.#*

# OS
.DS_Store
```

### Step 6: Verify setup

Run the following commands to verify:

```bash
# Check Emacs version
emacs --version

# Check Elixir version
elixir --version

# Run tests
make test

# Compile
make compile
```

## Acceptance Criteria

- [ ] `ob-elixir.el` exists with proper headers
- [ ] Package loads without errors: `(require 'ob-elixir)`
- [ ] `make test` runs successfully
- [ ] `make compile` produces no warnings
- [ ] All files follow Emacs Lisp conventions

## Files Created

- `ob-elixir.el` - Main package file
- `Eldev` - Build tool configuration
- `Makefile` - Make targets
- `test/test-ob-elixir.el` - Test file
- `.gitignore` - Git ignore rules

## References

- [docs/01-emacs-elisp-best-practices.md](../docs/01-emacs-elisp-best-practices.md)
- [docs/02-testing-emacs-elisp.md](../docs/02-testing-emacs-elisp.md)