# This file originates from composer2nix

{ stdenv, writeTextFile, fetchurl, php, unzip }:

let
  composer = stdenv.mkDerivation {
    name = "composer-1.6.5";
    src = fetchurl {
      url = https://github.com/composer/composer/releases/download/1.6.5/composer.phar;
      sha256 = "07xkpg9y1dd4s33y3cbf7r5fphpgc39mpm066a8m9y4ffsf539f0";
    };
    buildInputs = [ php ];

    # We must wrap the composer.phar because of the impure shebang.
    # We cannot use patchShebangs because the executable verifies its own integrity and will detect that somebody has tampered with it.

    buildCommand = ''
      # Copy phar file
      mkdir -p $out/share/php
      cp $src $out/share/php/composer.phar
      chmod 755 $out/share/php/composer.phar

      # Create wrapper executable
      mkdir -p $out/bin
      cat > $out/bin/composer <<EOF
      #! ${stdenv.shell} -e
      exec ${php}/bin/php $out/share/php/composer.phar "\$@"
      EOF
      chmod +x $out/bin/composer
    '';
    meta = {
      description = "Dependency Manager for PHP";
      #license = stdenv.licenses.mit;
      maintainers = [ stdenv.lib.maintainers.sander ];
      platforms = stdenv.lib.platforms.unix;
    };
  };

  buildZipPackage = { name, src }:
    stdenv.mkDerivation {
      inherit name src;
      buildInputs = [ unzip ];
      buildCommand = ''
        unzip $src
        baseDir=$(find . -type d -mindepth 1 -maxdepth 1)
        cd $baseDir
        mkdir -p $out
        mv * $out
      '';
    };

  buildPackage =
    { name
    , src
    , packages ? {}
    , devPackages ? {}
    , buildInputs ? []
    , symlinkDependencies ? false
    , executable ? false
    , removeComposerArtifacts ? false
    , postInstall ? ""
    , noDev ? false
    , unpackPhase ? "true"
    , buildPhase ? "true"
    , ...}@args:

    let
      reconstructInstalled = writeTextFile {
        name = "reconstructinstalled.php";
        executable = true;
        text = ''
          #! ${php}/bin/php
          <?php
          if(file_exists($argv[1]))
          {
              $composerLockStr = file_get_contents($argv[1]);

              if($composerLockStr === false)
              {
                  fwrite(STDERR, "Cannot open composer.lock contents\n");
                  exit(1);
              }
              else
              {
                  $config = json_decode($composerLockStr, true);

                  if(array_key_exists("packages", $config))
                      $allPackages = $config["packages"];
                  else
                      $allPackages = array();

                  ${stdenv.lib.optionalString (!noDev) ''
                    if(array_key_exists("packages-dev", $config))
                        $allPackages = array_merge($allPackages, $config["packages-dev"]);
                  ''}

                  $packagesStr = json_encode($allPackages, JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES);
                  print($packagesStr);
              }
          }
          else
              print("[]");
          ?>
        '';
      };

      constructBin = writeTextFile {
        name = "constructbin.php";
        executable = true;
        text = ''
          #! ${php}/bin/php
          <?php
          $composerJSONStr = file_get_contents($argv[1]);

          if($composerJSONStr === false)
          {
              fwrite(STDERR, "Cannot open composer.json contents\n");
              exit(1);
          }
          else
          {
              $config = json_decode($composerJSONStr, true);

              if(array_key_exists("bin-dir", $config))
                  $binDir = $config["bin-dir"];
              else
                  $binDir = "bin";

              if(array_key_exists("bin", $config))
              {
                  if(!file_exists("vendor/".$binDir))
                      mkdir("vendor/".$binDir);

                  foreach($config["bin"] as $bin)
                      symlink("../../".$bin, "vendor/".$binDir."/".basename($bin));
              }
          }
          ?>
        '';
      };

      bundleDependencies = dependencies:
        stdenv.lib.concatMapStrings (dependencyName:
          let
            dependency = dependencies.${dependencyName};
          in
          ''
            ${if dependency.targetDir == "" then ''
              vendorDir="$(dirname ${dependencyName})"
              mkdir -p "$vendorDir"
              ${if symlinkDependencies then
                ''ln -s "${dependency.src}" "$vendorDir/$(basename "${dependencyName}")"''
                else
                ''cp -av "${dependency.src}" "$vendorDir/$(basename "${dependencyName}")"''
              }
            '' else ''
              namespaceDir="${dependencyName}/$(dirname "${dependency.targetDir}")"
              mkdir -p "$namespaceDir"
              ${if symlinkDependencies then
                ''ln -s "${dependency.src}" "$namespaceDir/$(basename "${dependency.targetDir}")"''
              else
                ''cp -av "${dependency.src}" "$namespaceDir/$(basename "${dependency.targetDir}")"''
              }
            ''}
          '') (builtins.attrNames dependencies);

      extraArgs = removeAttrs args [ "name" "packages" "devPackages" "buildInputs" ];
    in
    stdenv.mkDerivation ({
      name = "composer-${name}";
      buildInputs = [ php composer ] ++ buildInputs;

      inherit unpackPhase buildPhase;

      installPhase = ''
        ${if executable then ''
          mkdir -p $out/share/php
          cp -av $src $out/share/php/$name
          chmod -R u+w $out/share/php/$name
          cd $out/share/php/$name
        '' else ''
          cp -av $src $out
          chmod -R u+w $out
          cd $out
        ''}

        # Remove unwanted files
        rm -f *.nix

        export HOME=$TMPDIR

        # Remove the provided vendor folder if it exists
        rm -Rf vendor

        # If there is no composer.lock file, compose a dummy file.
        # Otherwise, composer attempts to download the package.json file from
        # the registry which we do not want.
        if [ ! -f composer.lock ]
        then
            cat > composer.lock <<EOF
        {
            "packages": []
        }
        EOF
        fi

        # Reconstruct the installed.json file from the lock file
        mkdir -p vendor/composer
        ${reconstructInstalled} composer.lock > vendor/composer/installed.json

        # Copy or symlink the provided dependencies
        cd vendor
        ${bundleDependencies packages}
        ${stdenv.lib.optionalString (!noDev) (bundleDependencies devPackages)}
        cd ..

        # Reconstruct autoload scripts
        # We use the optimize feature because Nix packages cannot change after they have been built
        # Using the dynamic loader for a Nix package is useless since there is nothing to dynamically reload.
        composer dump-autoload --optimize ${stdenv.lib.optionalString noDev "--no-dev"}

        # Run the install step as a validation to confirm that everything works out as expected
        composer install --optimize-autoloader ${stdenv.lib.optionalString noDev "--no-dev"}

        ${stdenv.lib.optionalString executable ''
          # Reconstruct the bin/ folder if we deploy an executable project
          ${constructBin} composer.json
          ln -s $(pwd)/vendor/bin $out/bin
        ''}

        ${stdenv.lib.optionalString (!symlinkDependencies) ''
          # Patch the shebangs if possible
          if [ -d $(pwd)/vendor/bin ]
          then
              # Look for all executables in bin/
              for i in $(pwd)/vendor/bin/*
              do
                  # Look for their location
                  realFile=$(readlink -f "$i")

                  # Restore write permissions
                  chmod u+wx "$(dirname "$realFile")"
                  chmod u+w "$realFile"

                  # Patch shebang
                  sed -e "s|#!/usr/bin/php|#!${php}/bin/php|" \
                      -e "s|#!/usr/bin/env php|#!${php}/bin/php|" \
                      "$realFile" > tmp
                  mv tmp "$realFile"
                  chmod u+x "$realFile"
              done
          fi
        ''}

        if [ "$removeComposerArtifacts" = "1" ]
        then
            # Remove composer stuff
            rm -f composer.json composer.lock
        fi

        # Execute post install hook
        runHook postInstall
    '';
  } // extraArgs);
in
{
  composer = stdenv.lib.makeOverridable composer;
  buildZipPackage = stdenv.lib.makeOverridable buildZipPackage;
  buildPackage = stdenv.lib.makeOverridable buildPackage;
}