# Keeps GitHub Actions cache storage from filling up.
#
# Two complementary triggers:
#
#   1. Weekly sweep — delete every cache older than 14 days. Catches the slow
#      drift from old branches and stale entries that nothing references.
#   2. PR-close sweep — when a pull request is merged or closed, delete every
#      cache scoped to that PR's branch. Most caches are short-lived per-PR
#      buildx scopes; without this they linger for the full retention window
#      eating quota for nothing.
#
# Storage quota on davidmonterocrespo24's plan is 0.5 GB. A multi-stage Docker
# build with mode=min cache can sit around 200-400 MB so two stale PR caches
# are enough to push us over.
name: Actions cache cleanup

on:
  schedule:
    # Sundays at 04:00 UTC — well outside CI peak hours.
    - cron: '0 4 * * 0'
  pull_request:
    types: [closed]
  workflow_dispatch: {}

jobs:
  weekly-sweep:
    if: github.event_name != 'pull_request'
    runs-on: ubuntu-latest
    permissions:
      actions: write
    steps:
      - name: Delete caches older than 14 days
        uses: actions/github-script@v7
        with:
          script: |
            const cutoffMs = Date.now() - 14 * 24 * 60 * 60 * 1000;
            let page = 1;
            let deleted = 0;
            let kept = 0;
            let bytesFreed = 0;
            while (true) {
              const { data } = await github.rest.actions.getActionsCacheList({
                owner: context.repo.owner,
                repo: context.repo.repo,
                per_page: 100,
                page,
              });
              if (!data.actions_caches.length) break;
              for (const cache of data.actions_caches) {
                const created = new Date(cache.created_at).getTime();
                if (created < cutoffMs) {
                  console.log(
                    `delete  ${cache.id}  ${(cache.size_in_bytes / 1024 / 1024).toFixed(1)} MB  ${cache.ref}  ${cache.key}`,
                  );
                  await github.rest.actions.deleteActionsCacheById({
                    owner: context.repo.owner,
                    repo: context.repo.repo,
                    cache_id: cache.id,
                  });
                  deleted += 1;
                  bytesFreed += cache.size_in_bytes;
                } else {
                  kept += 1;
                }
              }
              if (data.actions_caches.length < 100) break;
              page += 1;
            }
            console.log(
              `summary: deleted=${deleted} kept=${kept} freed=${(bytesFreed / 1024 / 1024).toFixed(1)} MB`,
            );

  pr-close-sweep:
    if: github.event_name == 'pull_request'
    runs-on: ubuntu-latest
    permissions:
      actions: write
    steps:
      - name: Delete caches scoped to the closed PR's branch
        uses: actions/github-script@v7
        env:
          PR_REF: refs/pull/${{ github.event.pull_request.number }}/merge
          BRANCH_REF: refs/heads/${{ github.event.pull_request.head.ref }}
        with:
          script: |
            const refs = [process.env.PR_REF, process.env.BRANCH_REF];
            let deleted = 0;
            let bytesFreed = 0;
            for (const ref of refs) {
              let page = 1;
              while (true) {
                const { data } = await github.rest.actions.getActionsCacheList({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  ref,
                  per_page: 100,
                  page,
                });
                if (!data.actions_caches.length) break;
                for (const cache of data.actions_caches) {
                  console.log(
                    `delete  ${cache.id}  ${(cache.size_in_bytes / 1024 / 1024).toFixed(1)} MB  ${cache.ref}  ${cache.key}`,
                  );
                  await github.rest.actions.deleteActionsCacheById({
                    owner: context.repo.owner,
                    repo: context.repo.repo,
                    cache_id: cache.id,
                  });
                  deleted += 1;
                  bytesFreed += cache.size_in_bytes;
                }
                if (data.actions_caches.length < 100) break;
                page += 1;
              }
            }
            console.log(
              `pr-close summary: deleted=${deleted} freed=${(bytesFreed / 1024 / 1024).toFixed(1)} MB`,
            );