// This adds top-level 'precommit' task with essential
// precommit validation checks.

import org.eclipse.jgit.api.*;
import org.eclipse.jgit.storage.file.FileRepositoryBuilder;
import org.eclipse.jgit.errors.*;


buildscript {
  repositories {
    mavenCentral()
  }

  dependencies {
    classpath 'org.eclipse.jgit:org.eclipse.jgit:5.3.0.201903130848-r'
    classpath 'commons-codec:commons-codec:1.6'
  }
}

def gitStatus(dir) {
  try {
    def repository = new FileRepositoryBuilder()
        .setWorkTree(dir)
        .setMustExist(true)
        .build()

    def status = new Git(repository).status().call()
    return status
  } catch (RepositoryNotFoundException | NoWorkTreeException e) {
    logger.warn("WARNING: Directory is not a valid GIT checkout (won't check dirty files): ${dir}")
    return null
  } catch (NotSupportedException e) {
    throw new GradleException("jgit does not support git repository version at this location: ${dir}", e)
  }
}

configure(rootProject) {
  // Verify git working copy does not have any unstaged modified files.
  task checkWorkingCopyClean() {
    doFirst {
      def status = gitStatus(rootProject.projectDir)
      if (status == null) {
        // Ignore the check. This isn't a git checkout.
      } else {
        def offenders = [
            // Exclude staged changes. These are fine in precommit.
            // "(added)": status.added,
            // "(changed)": status.changed,
            // "(removed)": status.removed,
            "(conflicting)": status.conflicting,
            "(missing)": status.missing,
            "(modified)": status.modified,
            "(untracked)": [status.untracked, status.untrackedFolders].flatten()
        ].collectMany { fileStatus, files ->
          files.collect {file -> "  - ${file} ${fileStatus}" }
        }.sort()

        if (offenders) {
          throw new GradleException("Working copy is not a clean git checkout, offending files:\n${offenders.join("\n")}")
        }
      }
    }
  }
}