dapp2.nix

{ solidityPackage, solc }:

let
  inherit (builtins) map listToAttrs attrNames attrValues length fromJSON readFile;
  mapAttrs = if (builtins ? mapAttrs)
    then builtins.mapAttrs
    else f: attrs:
      listToAttrs (map
        (name: { inherit name; value = f name attrs."${name}"; })
        (attrNames attrs));

  defaults = {
    inherit solc;
    doCheck = false;
  };

  package = spec: let
    spec' = defaults // (removeAttrs spec [ "repo" "repo'" "src'" ]);
    deps = map (spec:
      package (spec // { inherit (spec') solc doCheck; })
    ) (attrValues spec'.deps);
  in solidityPackage (spec' // { inherit deps; });

  packageSpecs = mapAttrs (_: package);

  jsonSpecs = fromJSON (readFile ./.dapp.json);

  resolveDeps = _: v:
    let
      contract = jsonSpecs.contracts."${v}";
      contract' = contract // {
        src = "${fetchGit contract.repo}/src";
      };
      noDeps = length (attrNames contract.deps) == 0;
    in
      if noDeps
      then contract'
      else contract' // { deps = mapAttrs resolveDeps contract.deps; };

  specs = (mapAttrs resolveDeps jsonSpecs.contracts) // {
    this = jsonSpecs.this // {
      deps = mapAttrs resolveDeps jsonSpecs.this.deps;
    };
  };
in {
  inherit package packageSpecs specs;
  this = package specs.this;
  deps = packageSpecs specs.this.deps;
}