import * as core from '@actions/core'
import * as dependencyGraph from './dependency-graph'
import * as github from '@actions/github'
import styles from 'ansi-styles'
import {RequestError} from '@octokit/request-error'
import {Change, Severity, Scope} from './schemas'
import {readConfig} from '../src/config'
import {
  filterChangesBySeverity,
  filterChangesByScopes,
  filterOutAllowedAdvisories
} from '../src/filter'
import {getDeniedLicenseChanges} from './licenses'
import * as summary from './summary'
import {getRefs} from './git-refs'

async function run(): Promise<void> {
  try {
    let failed = false
    const config = readConfig()
    const refs = getRefs(config, github.context)

    const changes = await dependencyGraph.compare({
      owner: github.context.repo.owner,
      repo: github.context.repo.repo,
      baseRef: refs.base,
      headRef: refs.head
    })

    const minSeverity = config.fail_on_severity

    const licenses = {
      allow: config.allow_licenses,
      deny: config.deny_licenses
    }

    const scopes = config.fail_on_scopes

    const scopedChanges = filterChangesByScopes(scopes as Scope[], changes)

    const allowedGhsas: string[] = config.allow_ghsas || []

    const filteredChanges = filterOutAllowedAdvisories(
      allowedGhsas,
      scopedChanges
    )

    const addedChanges = filterChangesBySeverity(
      minSeverity as Severity,
      filteredChanges
    ).filter(
      change =>
        change.change_type === 'added' &&
        change.vulnerabilities !== undefined &&
        change.vulnerabilities.length > 0
    )

    const [licenseErrors, unknownLicenses] = getDeniedLicenseChanges(
      filteredChanges,
      licenses
    )

    summary.addSummaryToSummary(addedChanges, licenseErrors, unknownLicenses)

    if (addedChanges.length > 0) {
      for (const change of addedChanges) {
        printChangeVulnerabilities(change)
      }
      failed = true
    }

    summary.addChangeVulnerabilitiesToSummary(addedChanges, minSeverity || '')

    if (licenseErrors.length > 0) {
      printLicensesError(licenseErrors)
      core.setFailed('Dependency review detected incompatible licenses.')
    }

    printNullLicenses(unknownLicenses)

    summary.addLicensesToSummary(licenseErrors, unknownLicenses, config)

    printScannedDependencies(changes)

    if (failed) {
      core.setFailed('Dependency review detected vulnerable packages.')
    } else {
      core.info(
        `Dependency review did not detect any vulnerable packages with severity level "${minSeverity}" or higher.`
      )
    }
  } catch (error) {
    if (error instanceof RequestError && error.status === 404) {
      core.setFailed(
        `Dependency review could not obtain dependency data for the specified owner, repository, or revision range.`
      )
    } else if (error instanceof RequestError && error.status === 403) {
      core.setFailed(
        `Dependency review is not supported on this repository. Please ensure that Dependency graph is enabled, see https://github.com/${github.context.repo.owner}/${github.context.repo.repo}/settings/security_analysis`
      )
    } else {
      if (error instanceof Error) {
        core.setFailed(error.message)
      } else {
        core.setFailed('Unexpected fatal error')
      }
    }
  } finally {
    await core.summary.write()
  }
}

function printChangeVulnerabilities(change: Change): void {
  for (const vuln of change.vulnerabilities) {
    core.info(
      `${styles.bold.open}${change.manifest} » ${change.name}@${
        change.version
      }${styles.bold.close} – ${vuln.advisory_summary} ${renderSeverity(
        vuln.severity
      )}`
    )
    core.info(`  ↪ ${vuln.advisory_url}`)
  }
}

function renderSeverity(
  severity: 'critical' | 'high' | 'moderate' | 'low'
): string {
  const color = (
    {
      critical: 'red',
      high: 'red',
      moderate: 'yellow',
      low: 'grey'
    } as const
  )[severity]
  return `${styles.color[color].open}(${severity} severity)${styles.color[color].close}`
}

function renderChangeType(
  change_type: 'added' | 'modified' | 'removed'
): string {
  const color = (
    {
      added: 'green',
      modified: 'yellow',
      removed: 'red'
    } as const
  )[change_type]
  return `${styles.color[color].open}${change_type}${styles.color[color].close}`
}

function printLicensesError(changes: Change[]): void {
  if (changes.length === 0) {
    return
  }

  core.info('\nThe following dependencies have incompatible licenses:\n')
  for (const change of changes) {
    core.info(
      `${styles.bold.open}${change.manifest} » ${change.name}@${change.version}${styles.bold.close} – License: ${styles.color.red.open}${change.license}${styles.color.red.close}`
    )
  }
}

function printNullLicenses(changes: Change[]): void {
  if (changes.length === 0) {
    return
  }

  core.info('\nWe could not detect a license for the following dependencies:\n')
  for (const change of changes) {
    core.info(
      `${styles.bold.open}${change.manifest} » ${change.name}@${change.version}${styles.bold.close}`
    )
  }
}

function printScannedDependencies(changes: Change[]): void {
  core.group('Dependency changes', async () => {
    // group changes by manifest
    const dependencies: Record<string, Change[]> = {}
    for (const change of changes) {
      if (dependencies[change.manifest] === undefined) {
        dependencies[change.manifest] = []
      }
      dependencies[change.manifest].push(change)
    }

    for (const [manifestName, manifestChanges] of Object.entries(
      dependencies
    )) {
      core.info(`${styles.bold.open}${manifestName}`)
      for (const change of manifestChanges) {
        core.info(
          `${renderChangeType(change.change_type)}\t ${change.name}@${
            change.version
          }`
        )
      }
    }
  })
}

run()