feat: Add documentation management module (WIP)

- Create vcs_docs crate for documentation handling
- Add build script and Cargo.toml
- NOTE: Core implementation pending

4 files changed, 215 insertions, 0 deletions

diff --git a/crates/vcs_docs/Cargo.toml b/crates/vcs_docs/Cargo.toml
new file mode 100644
index 0000000..285b83d
--- /dev/null
+++ b/crates/vcs_docs/Cargo.toml
@@ -0,0 +1,6 @@
+[package]
+name = "vcs_docs"
+edition = "2024"
+version.workspace = true
+
+[dependencies]
diff --git a/crates/vcs_docs/build.rs b/crates/vcs_docs/build.rs
new file mode 100644
index 0000000..79d1b32
--- /dev/null
+++ b/crates/vcs_docs/build.rs
@@ -0,0 +1,182 @@
+use std::env;
+use std::fs;
+use std::io::{self, Write};
+use std::path::Path;
+
+// Template markers for code generation
+const TEMPLATE_DOCUMENT_BEGIN: &str = "--- TEMPLATE DOCUMENT BEGIN ---";
+const TEMPLATE_DOCUMENT_END: &str = "--- TEMPLATE DOCUMENT END ---";
+const TEMPLATE_FUNC_BEGIN: &str = "--- TEMPLATE FUNC BEGIN ---";
+const TEMPLATE_FUNC_END: &str = "--- TEMPLATE FUNC END ---";
+const TEMPLATE_LIST_BEGIN: &str = "--- TEMPLATE LIST BEGIN ---";
+const TEMPLATE_LIST_END: &str = "--- TEMPLATE LIST END ---";
+
+// Template parameter patterns for substitution
+const PARAM_DOCUMENT_PATH: &str = "{{DOCUMENT_PATH}}";
+const PARAM_DOCUMENT_CONSTANT_NAME: &str = "{{DOCUMENT_CONSTANT_NAME}}";
+const PARAM_DOCUMENT_CONTENT: &str = "{{DOCUMENT_CONTENT}}";
+const PARAM_DOCUMENT_PATH_SNAKE_CASE: &str = "{{DOCUMENT_PATH_SNAKE_CASE}}";
+
+fn main() -> io::Result<()> {
+    println!("cargo:rerun-if-changed=src/docs.rs.template");
+    println!("cargo:rerun-if-changed=../../docs/Documents");
+
+    let out_dir = env::var("OUT_DIR").unwrap();
+    let dest_path = Path::new(&out_dir).join("docs.rs");
+
+    // Read all markdown files from docs directory recursively
+    let docs_dir = Path::new("../../docs/Documents");
+    let mut documents = Vec::new();
+
+    if docs_dir.exists() {
+        collect_markdown_files(&docs_dir, &mut documents)?;
+    }
+
+    // Read template file
+    let template_path = Path::new("src/docs.rs.template");
+    let template_content = fs::read_to_string(template_path)?;
+
+    // Extract template sections preserving original indentation
+    let document_template = template_content
+        .split(TEMPLATE_DOCUMENT_BEGIN)
+        .nth(1)
+        .and_then(|s| s.split(TEMPLATE_DOCUMENT_END).next())
+        .unwrap_or("")
+        .trim_start_matches('\n')
+        .trim_end_matches('\n');
+
+    let match_arm_template = template_content
+        .split(TEMPLATE_FUNC_BEGIN)
+        .nth(1)
+        .and_then(|s| s.split(TEMPLATE_FUNC_END).next())
+        .unwrap_or("")
+        .trim_start_matches('\n')
+        .trim_end_matches('\n');
+
+    // Generate document blocks and match arms
+    let mut document_blocks = String::new();
+    let mut match_arms = String::new();
+    let mut list_items = String::new();
+
+    for (relative_path, content) in &documents {
+        // Calculate parameters for template substitution
+        let document_path = format!("./docs/Documents/{}", relative_path);
+
+        // Generate constant name from relative path
+        let document_constant_name = relative_path
+            .replace('/', "_")
+            .replace('-', "_")
+            .replace(".md", "")
+            .replace(".txt", "")
+            .to_uppercase();
+
+        // Generate snake_case name for function matching
+        let document_path_snake_case = relative_path
+            .replace('/', "_")
+            .replace('-', "_")
+            .replace(".md", "")
+            .replace(".txt", "")
+            .to_lowercase();
+
+        // Replace template parameters in document block preserving indentation
+        let document_block = document_template
+            .replace(PARAM_DOCUMENT_PATH, &document_path)
+            .replace(PARAM_DOCUMENT_CONSTANT_NAME, &document_constant_name)
+            .replace(PARAM_DOCUMENT_CONTENT, content.trim())
+            .replace("r#\"\"#", &format!("r#\"{}\"#", content.trim()));
+
+        document_blocks.push_str(&document_block);
+        document_blocks.push_str("\n\n");
+
+        // Replace template parameters in match arm preserving indentation
+        let match_arm = match_arm_template
+            .replace(PARAM_DOCUMENT_PATH_SNAKE_CASE, &document_path_snake_case)
+            .replace(PARAM_DOCUMENT_CONSTANT_NAME, &document_constant_name);
+
+        match_arms.push_str(&match_arm);
+        match_arms.push_str("\n");
+
+        // Generate list item for documents() function
+        let list_item = format!("        \"{}\".to_string(),", document_path_snake_case);
+        list_items.push_str(&list_item);
+        list_items.push_str("\n");
+    }
+
+    // Remove trailing newline from the last list item
+    if !list_items.is_empty() {
+        list_items.pop();
+    }
+
+    // Build final output by replacing template sections
+    let mut output = String::new();
+
+    // Add header before document blocks
+    if let Some(header) = template_content.split(TEMPLATE_DOCUMENT_BEGIN).next() {
+        output.push_str(header.trim());
+        output.push_str("\n\n");
+    }
+
+    // Add document blocks
+    output.push_str(&document_blocks);
+
+    // Add function section
+    if let Some(func_section) = template_content.split(TEMPLATE_FUNC_BEGIN).next() {
+        if let Some(rest) = func_section.split(TEMPLATE_DOCUMENT_END).nth(1) {
+            output.push_str(rest.trim());
+            output.push_str("\n");
+        }
+    }
+
+    // Add match arms
+    output.push_str(&match_arms);
+
+    // Add list items for documents() function
+    if let Some(list_section) = template_content.split(TEMPLATE_LIST_BEGIN).next() {
+        if let Some(rest) = list_section.split(TEMPLATE_FUNC_END).nth(1) {
+            output.push_str(rest.trim());
+            output.push_str("\n");
+        }
+    }
+    output.push_str(&list_items);
+
+    // Add footer
+    if let Some(footer) = template_content.split(TEMPLATE_LIST_END).nth(1) {
+        // Preserve original indentation in footer
+        output.push_str(footer);
+    }
+
+    // Write generated file
+    let mut file = fs::File::create(&dest_path)?;
+    file.write_all(output.as_bytes())?;
+
+    // Copy to src directory for development
+    let src_dest_path = Path::new("src/docs.rs");
+    fs::write(src_dest_path, output)?;
+
+    Ok(())
+}
+
+fn collect_markdown_files(dir: &Path, documents: &mut Vec<(String, String)>) -> io::Result<()> {
+    for entry in fs::read_dir(dir)? {
+        let entry = entry?;
+        let path = entry.path();
+
+        if path.is_dir() {
+            collect_markdown_files(&path, documents)?;
+        } else if path
+            .extension()
+            .map_or(false, |ext| ext == "md" || ext == "txt")
+        {
+            if let Ok(relative_path) = path.strip_prefix("../../docs/Documents") {
+                if let Some(relative_path_str) = relative_path.to_str() {
+                    let content = fs::read_to_string(&path)?;
+                    documents.push((
+                        relative_path_str.trim_start_matches('/').to_string(),
+                        content,
+                    ));
+                }
+            }
+        }
+    }
+    Ok(())
+}
diff --git a/crates/vcs_docs/src/docs.rs.template b/crates/vcs_docs/src/docs.rs.template
new file mode 100644
index 0000000..c6787d9
--- /dev/null
+++ b/crates/vcs_docs/src/docs.rs.template
@@ -0,0 +1,26 @@
+// Auto-generated code.
+
+--- TEMPLATE DOCUMENT BEGIN ---
+/// From {{DOCUMENT_PATH}}
+pub const {{DOCUMENT_CONSTANT_NAME}}: &str = "{{DOCUMENT_CONTENT}}";
+
+--- TEMPLATE DOCUMENT END ---
+
+// Get document content by name
+pub fn document(name: impl AsRef<str>) -> Option<String> {
+    match name.as_ref() {
+--- TEMPLATE FUNC BEGIN ---
+        "{{DOCUMENT_PATH_SNAKE_CASE}}" => Some({{DOCUMENT_CONSTANT_NAME}}.to_string()),
+--- TEMPLATE FUNC END ---
+        _ => None,
+    }
+}
+
+// Get list of all available document names
+pub fn documents() -> Vec<String> {
+    vec![
+--- TEMPLATE LIST BEGIN ---
+        "{{DOCUMENT_PATH_SNAKE_CASE}}".to_string(),
+--- TEMPLATE LIST END ---
+    ]
+}
diff --git a/crates/vcs_docs/src/lib.rs b/crates/vcs_docs/src/lib.rs
new file mode 100644
index 0000000..ca422a9
--- /dev/null
+++ b/crates/vcs_docs/src/lib.rs
@@ -0,0 +1 @@
+pub mod docs;