feat: implement cohesive site structure

Add content type handling and multi-page generation:

- content.rs: Add ContentKind enum (Post, Page, Section, Project)
  and extend Frontmatter with weight/link_to fields
- templates.rs: Add render_page, render_homepage,
  render_blog_index, render_projects_index templates
- main.rs: Process all content types with dedicated handlers

Output structure:
- /index.html (homepage from _index.md)
- /blog/index.html (post listing, sorted by date)
- /blog/<slug>/index.html (individual posts)
- /about/index.html, /collab/index.html (standalone pages)
- /projects/index.html (project cards with external links)

src/content.rs

@@ -1,10 +1,23 @@
 //! Content discovery and frontmatter parsing.
 
 use crate::error::{Error, Result};
-use gray_matter::{engine::YAML, Matter};
+use gray_matter::{Matter, engine::YAML};
 use std::fs;
 use std::path::{Path, PathBuf};
 
+/// The type of content being processed.
+#[derive(Debug, Clone, PartialEq)]
+pub enum ContentKind {
+    /// Blog post with full metadata (date, tags, etc.)
+    Post,
+    /// Standalone page (about, collab)
+    Page,
+    /// Section index (_index.md)
+    Section,
+    /// Project card with external link
+    Project,
+}
+
 /// Parsed frontmatter from a content file.
 #[derive(Debug)]
 pub struct Frontmatter {
@@ -12,11 +25,16 @@ pub struct Frontmatter {
     pub description: Option<String>,
     pub date: Option<String>,
     pub tags: Vec<String>,
+    /// For project cards: sort order
+    pub weight: Option<i64>,
+    /// For project cards: external link
+    pub link_to: Option<String>,
 }
 
 /// A content item ready for rendering.
 #[derive(Debug)]
 pub struct Content {
+    pub kind: ContentKind,
     pub frontmatter: Frontmatter,
     pub body: String,
     pub source_path: PathBuf,
@@ -24,9 +42,12 @@ pub struct Content {
 }
 
 impl Content {
-    /// Load and parse a markdown file with TOML frontmatter.
+    /// Load and parse a markdown file with YAML frontmatter.
-    pub fn from_path(path: impl AsRef<Path>) -> Result<Self> {
+    pub fn from_path(path: impl AsRef<Path>, kind: ContentKind) -> Result<Self> {
-        let path = path.as_ref();
+        Self::from_path_inner(path.as_ref(), kind)
+    }
+
+    fn from_path_inner(path: &Path, kind: ContentKind) -> Result<Self> {
         let raw = fs::read_to_string(path).map_err(|e| Error::ReadFile {
             path: path.to_path_buf(),
             source: e,
@@ -45,6 +66,7 @@ impl Content {
             .to_string();
 
         Ok(Content {
+            kind,
             frontmatter,
             body: parsed.content,
             source_path: path.to_path_buf(),
@@ -60,10 +82,20 @@ impl Content {
             .strip_prefix(content_root)
             .unwrap_or(&self.source_path);
 
+        match self.kind {
+            ContentKind::Section => {
+                // _index.md → parent/index.html
+                let parent = relative.parent().unwrap_or(Path::new(""));
+                parent.join("index.html")
+            }
+            _ => {
+                // Regular content → parent/slug/index.html
                 let parent = relative.parent().unwrap_or(Path::new(""));
                 parent.join(&self.slug).join("index.html")
             }
         }
+    }
+}
 
 fn parse_frontmatter(path: &Path, parsed: &gray_matter::ParsedEntity) -> Result<Frontmatter> {
     let data = parsed.data.as_ref().ok_or_else(|| Error::Frontmatter {
@@ -86,6 +118,8 @@ fn parse_frontmatter(path: &Path, parsed: &gray_matter::ParsedEntity) -> Result<
 
     let description = pod.get("description").and_then(|v| v.as_string().ok());
     let date = pod.get("date").and_then(|v| v.as_string().ok());
+    let weight = pod.get("weight").and_then(|v| v.as_i64().ok());
+    let link_to = pod.get("link_to").and_then(|v| v.as_string().ok());
 
     // Handle nested taxonomies.tags structure
     let tags = if let Some(taxonomies) = pod.get("taxonomies") {
@@ -111,5 +145,7 @@ fn parse_frontmatter(path: &Path, parsed: &gray_matter::ParsedEntity) -> Result<
         description,
         date,
         tags,
+        weight,
+        link_to,
     })
 }

src/main.rs

@@ -7,7 +7,7 @@ mod error;
 mod render;
 mod templates;
 
-use crate::content::Content;
+use crate::content::{Content, ContentKind};
 use crate::error::{Error, Result};
 use std::fs;
 use std::path::Path;
@@ -27,29 +27,69 @@ fn run() -> Result<()> {
         return Err(Error::ContentDirNotFound(content_dir.to_path_buf()));
     }
 
-    // For MVP: process all markdown files in content/blog/
+    // 1. Process blog posts
+    let mut posts = process_blog_posts(content_dir, output_dir)?;
+
+    // 2. Generate blog index (sorted by date, newest first)
+    posts.sort_by(|a, b| b.frontmatter.date.cmp(&a.frontmatter.date));
+    generate_blog_index(output_dir, &posts)?;
+
+    // 3. Process standalone pages (about, collab)
+    process_pages(content_dir, output_dir)?;
+
+    // 4. Process projects and generate project index
+    let mut projects = process_projects(content_dir)?;
+    projects.sort_by(|a, b| {
+        a.frontmatter
+            .weight
+            .unwrap_or(99)
+            .cmp(&b.frontmatter.weight.unwrap_or(99))
+    });
+    generate_projects_index(output_dir, &projects)?;
+
+    // 5. Generate homepage
+    generate_homepage(content_dir, output_dir)?;
+
+    eprintln!("done!");
+    Ok(())
+}
+
+/// Process all blog posts in content/blog/
+fn process_blog_posts(content_dir: &Path, output_dir: &Path) -> Result<Vec<Content>> {
     let blog_dir = content_dir.join("blog");
+    let mut posts = Vec::new();
 
     for entry in walkdir::WalkDir::new(&blog_dir)
         .into_iter()
         .filter_map(|e| e.ok())
         .filter(|e| {
-            e.path().extension().map_or(false, |ext| ext == "md")
+            e.path().extension().is_some_and(|ext| ext == "md")
-                && e.path().file_name().map_or(false, |n| n != "_index.md")
+                && e.path().file_name().is_some_and(|n| n != "_index.md")
         })
     {
         let path = entry.path();
         eprintln!("processing: {}", path.display());
 
-        let content = Content::from_path(path)?;
+        let content = Content::from_path(path, ContentKind::Post)?;
         let html_body = render::markdown_to_html(&content.body);
         let page = templates::render_post(&content.frontmatter, &html_body);
 
-        let out_path = output_dir.join(content.output_path(content_dir));
+        write_output(output_dir, content_dir, &content, page.into_string())?;
-        let out_dir = out_path.parent().unwrap();
+        posts.push(content);
+    }
 
-        fs::create_dir_all(out_dir).map_err(|e| Error::CreateDir {
+    Ok(posts)
-            path: out_dir.to_path_buf(),
+}
+
+/// Generate the blog listing page
+fn generate_blog_index(output_dir: &Path, posts: &[Content]) -> Result<()> {
+    let out_path = output_dir.join("blog/index.html");
+    eprintln!("generating: {}", out_path.display());
+
+    let page = templates::render_blog_index("Blog", posts);
+
+    fs::create_dir_all(out_path.parent().unwrap()).map_err(|e| Error::CreateDir {
+        path: out_path.parent().unwrap().to_path_buf(),
         source: e,
     })?;
 
@@ -59,8 +99,112 @@ fn run() -> Result<()> {
     })?;
 
     eprintln!("  → {}", out_path.display());
-    }
+    Ok(())
-
+}
-    eprintln!("done!");
+
+/// Process standalone pages in content/ (about.md, collab.md)
+fn process_pages(content_dir: &Path, output_dir: &Path) -> Result<()> {
+    for name in ["about.md", "collab.md"] {
+        let path = content_dir.join(name);
+        if path.exists() {
+            eprintln!("processing: {}", path.display());
+
+            let content = Content::from_path(&path, ContentKind::Page)?;
+            let html_body = render::markdown_to_html(&content.body);
+            let page = templates::render_page(&content.frontmatter, &html_body);
+
+            write_output(output_dir, content_dir, &content, page.into_string())?;
+        }
+    }
+    Ok(())
+}
+
+/// Load all project cards (without writing individual pages)
+fn process_projects(content_dir: &Path) -> Result<Vec<Content>> {
+    let projects_dir = content_dir.join("projects");
+    let mut projects = Vec::new();
+
+    for entry in walkdir::WalkDir::new(&projects_dir)
+        .into_iter()
+        .filter_map(|e| e.ok())
+        .filter(|e| {
+            e.path().extension().is_some_and(|ext| ext == "md")
+                && e.path().file_name().is_some_and(|n| n != "_index.md")
+        })
+    {
+        let content = Content::from_path(entry.path(), ContentKind::Project)?;
+        projects.push(content);
+    }
+
+    Ok(projects)
+}
+
+/// Generate the projects listing page
+fn generate_projects_index(output_dir: &Path, projects: &[Content]) -> Result<()> {
+    let out_path = output_dir.join("projects/index.html");
+    eprintln!("generating: {}", out_path.display());
+
+    let page = templates::render_projects_index("Projects", projects);
+
+    fs::create_dir_all(out_path.parent().unwrap()).map_err(|e| Error::CreateDir {
+        path: out_path.parent().unwrap().to_path_buf(),
+        source: e,
+    })?;
+
+    fs::write(&out_path, page.into_string()).map_err(|e| Error::WriteFile {
+        path: out_path.clone(),
+        source: e,
+    })?;
+
+    eprintln!("  → {}", out_path.display());
+    Ok(())
+}
+
+/// Generate the homepage from content/_index.md
+fn generate_homepage(content_dir: &Path, output_dir: &Path) -> Result<()> {
+    let index_path = content_dir.join("_index.md");
+    eprintln!("generating: homepage");
+
+    let content = Content::from_path(&index_path, ContentKind::Section)?;
+    let html_body = render::markdown_to_html(&content.body);
+    let page = templates::render_homepage(&content.frontmatter, &html_body);
+
+    let out_path = output_dir.join("index.html");
+
+    fs::create_dir_all(output_dir).map_err(|e| Error::CreateDir {
+        path: output_dir.to_path_buf(),
+        source: e,
+    })?;
+
+    fs::write(&out_path, page.into_string()).map_err(|e| Error::WriteFile {
+        path: out_path.clone(),
+        source: e,
+    })?;
+
+    eprintln!("  → {}", out_path.display());
+    Ok(())
+}
+
+/// Write a content item to its output path
+fn write_output(
+    output_dir: &Path,
+    content_dir: &Path,
+    content: &Content,
+    html: String,
+) -> Result<()> {
+    let out_path = output_dir.join(content.output_path(content_dir));
+    let out_dir = out_path.parent().unwrap();
+
+    fs::create_dir_all(out_dir).map_err(|e| Error::CreateDir {
+        path: out_dir.to_path_buf(),
+        source: e,
+    })?;
+
+    fs::write(&out_path, html).map_err(|e| Error::WriteFile {
+        path: out_path.clone(),
+        source: e,
+    })?;
+
+    eprintln!("  → {}", out_path.display());
     Ok(())
 }

src/templates.rs

@@ -1,7 +1,7 @@
 //! HTML templates using maud.
 
-use crate::content::Frontmatter;
+use crate::content::{Content, Frontmatter};
-use maud::{html, Markup, DOCTYPE};
+use maud::{DOCTYPE, Markup, PreEscaped, html};
 
 /// Render a blog post with the base layout.
 pub fn render_post(frontmatter: &Frontmatter, content_html: &str) -> Markup {
@@ -26,7 +26,94 @@ pub fn render_post(frontmatter: &Frontmatter, content_html: &str) -> Markup {
                     }
                 }
                 section.content {
-                    (maud::PreEscaped(content_html))
+                    (PreEscaped(content_html))
+                }
+            }
+        },
+    )
+}
+
+/// Render a standalone page (about, collab, etc.)
+pub fn render_page(frontmatter: &Frontmatter, content_html: &str) -> Markup {
+    base_layout(
+        &frontmatter.title,
+        html! {
+            article.page {
+                h1 { (frontmatter.title) }
+                section.content {
+                    (PreEscaped(content_html))
+                }
+            }
+        },
+    )
+}
+
+/// Render the homepage.
+pub fn render_homepage(frontmatter: &Frontmatter, content_html: &str) -> Markup {
+    base_layout(
+        &frontmatter.title,
+        html! {
+            section.hero {
+                h1 { (frontmatter.title) }
+                @if let Some(ref desc) = frontmatter.description {
+                    p.tagline { (desc) }
+                }
+            }
+            section.content {
+                (PreEscaped(content_html))
+            }
+        },
+    )
+}
+
+/// Render the blog listing page.
+pub fn render_blog_index(title: &str, posts: &[Content]) -> Markup {
+    base_layout(
+        title,
+        html! {
+            h1 { (title) }
+            ul.post-list {
+                @for post in posts {
+                    li {
+                        a href=(format!("/blog/{}/", post.slug)) {
+                            span.title { (post.frontmatter.title) }
+                            @if let Some(ref date) = post.frontmatter.date {
+                                time.date { (date) }
+                            }
+                        }
+                        @if let Some(ref desc) = post.frontmatter.description {
+                            p.description { (desc) }
+                        }
+                    }
+                }
+            }
+        },
+    )
+}
+
+/// Render the projects page with cards.
+pub fn render_projects_index(title: &str, projects: &[Content]) -> Markup {
+    base_layout(
+        title,
+        html! {
+            h1 { (title) }
+            ul.project-cards {
+                @for project in projects {
+                    li.card {
+                        @if let Some(ref link) = project.frontmatter.link_to {
+                            a href=(link) target="_blank" rel="noopener" {
+                                h2 { (project.frontmatter.title) }
+                                @if let Some(ref desc) = project.frontmatter.description {
+                                    p { (desc) }
+                                }
+                            }
+                        } @else {
+                            h2 { (project.frontmatter.title) }
+                            @if let Some(ref desc) = project.frontmatter.description {
+                                p { (desc) }
+                            }
+                        }
+                    }
                 }
             }
         },