type head_data = { page_title : string }

type body_data = {
  title : string;
  subtitle : string;
  topnav : Dream_html.node;
  content : Dream_html.node list;
}

module Layout = struct
  open Dream_html
  open HTML

  let header title subtitle =
    null [ h1 [] [ txt "%s" title ]; h2 [] [ txt "%s" subtitle ] ]

  let footer name =
    let today = Unix.localtime (Unix.time ()) in
    let year = today.Unix.tm_year + 1900 |> string_of_int in
    let space = " " in
    let footer_text = String.concat space [ "©"; year; name ] in
    footer [] [ txt "%s" footer_text ]

  let head_data = { page_title = "Ogit" }

  let application ?(head_data = head_data) body_data =
    html []
      [
        head []
          [
            title [] "%s" head_data.page_title;
            link [ rel "stylesheet"; href "/static/styles.css" ];
          ];
        body []
          [
            header body_data.title body_data.subtitle;
            body_data.topnav;
            div [ id "main" ] body_data.content;
            footer "Marius PETER";
          ];
      ]
end

module Ogit_root = struct
  open Dream_html
  open HTML

  let repositories_in directory =
    let repositories = Sys.readdir directory |> Array.to_list
    and li_of_repo repo = li [] [ a [ href "%s" repo ] [ txt "%s" repo ] ] in
    div [ id "repositories" ] [ ul [] @@ List.map li_of_repo repositories ]

  let body_data =
    {
      title = "My repositories";
      subtitle = "Repositories for " ^ Config.author;
      topnav = null [];
      content = [ repositories_in Config.git_directory ];
    }

  let render () = Lwt.return @@ Layout.application body_data
end

module Repo_root = struct
  open Dream_html
  open HTML
  open Git
  open Lwt.Infix

  let topnav =
    nav
      [ id "top" ]
      [
        ul []
          [
            li [] [ a [ href "/" ] [ txt "Home" ] ];
            li [] [ a [ href "/" ] [ txt "Refs" ] ];
            li [] [ a [ href "/" ] [ txt "Log" ] ];
            li [] [ a [ href "/" ] [ txt "Tree" ] ];
            li [] [ a [ href "/" ] [ txt "Commit" ] ];
            li [] [ a [ href "/" ] [ txt "Diff" ] ];
          ];
      ]

  let render repo_name =
    let repo_path = Filename.concat Config.git_directory repo_name in

    (* 1. Open the Git repository *)
    let%lwt repo =
      Git_unix.Store.v (Fpath.v repo_path) >>= function
      | Ok repo -> Lwt.return repo
      | Error _ -> Lwt.fail_with "Could not open the Git repository."
    in

    (* 2. Resolve HEAD to get the latest commit hash *)
    let%lwt commit_hash =
      Git_unix.Store.Ref.resolve repo Reference.master >>= function
      | Ok hash -> Lwt.return hash
      | Error _ -> Lwt.fail_with "Failed to resolve HEAD"
    in

    (* (\* 3. Read the commit *\) *)
    (* let%lwt commit =  *)
    (*   Commit.v repo commit_hash >>= function *)
    (*   | Ok commit -> Lwt.return commit *)
    (*   | Error _ -> Lwt.fail_with "Failed to read the commit." *)
    (* in *)

    (* (\* 4. Read the tree from the commit *\) *)
    (* let%lwt tree = *)
    (*   Tree.v commit.Commit.tree >>= function *)
    (*   | Ok tree -> Lwt.return tree *)
    (*   | Error _ -> Lwt.fail_with "Failed to read the tree." *)
    (* in *)

    (* (\* 5. Generate HTML list items for each tree entry *\) *)
    (* let entries = Tree.entries tree in *)
    (* let items = *)
    (*   List.map *)
    (*     (fun entry -> *)
    (*       let icon = match entry.Tree.perm with `Dir -> "📁 " | _ -> "📄 " in *)
    (*       li [] [ a [ href "#" ] [ txt (icon ^ entry.Tree.name) ] ]) *)
    (*     entries *)
    (* in *)

    (* 6. Assemble the page *)
    let content =
      [ ul [] [ li [] [ txt "%s" (commit_hash |> Digestif.SHA1.to_hex) ] ] ]
    in
    let title = repo_name in
    let subtitle = Git_unix.(repo |> Store.root |> Fpath.to_string) in
    let body_data = { title; subtitle; topnav; content } in
    Lwt.return @@ Layout.application body_data
end

module Repo_tree = struct
  open Dream_html
  open HTML

  let render repo_name =
    let title = repo_name and content = [ txt "foobar" ] in
    let subtitle = "Dinglefops" in
    let topnav = null [] in
    let body_data = { title; subtitle; topnav; content } in
    Lwt.return @@ Layout.application body_data
end