# release.ludic — versioning + release cutting for the toolchain.
#
#   ludic version              print the toolchain version (from the VERSION file)
#   ludic-dev release [level]      cut a release: aggregate changes/ into CHANGELOG.md,
#                          bump VERSION, commit, and tag vX.Y.Z. `level` is
#                          major|minor|patch; omitted, it is derived from the
#                          highest `bump:` among the pending changesets.
#   ludic-dev release [level] --dry-run   render the changelog section to stdout and
#                          stop: nothing is written, committed, tagged or pushed.
#   ludic-dev release [level] --publish   ...then push main + the tag and create a
#                          Forgejo release with source + toolchain tarballs.
#                          Needs FORGEJO_TOKEN in the environment.
#
# The scheme is SemVer. VERSION is the single source of truth (ludicc --version
# reads it at runtime), so a bump touches one file and never reseeds the
# compiler. Changesets live as one small Markdown file per change under changes/
# (see changes/README.md); a release consumes them into a CHANGELOG.md section.

# the current version string, or a fallback when VERSION is absent
function read_version_or(dflt: pointer) -> pointer {
  let v = capture_line("cat VERSION 2>/dev/null")
  if (v == "") { return dflt }
  return v
}

# true when there is at least one pending changeset (changes/*.md, minus README)
function has_changesets() -> bool {
  return capture_line("ls changes/*.md 2>/dev/null | grep -v '/README.md' | head -1") != ""
}

# the highest bump level requested across the pending changesets ("" if none).
# README.md is excluded — its format example carries a literal `bump:` line that
# must not count as a real changeset.
function highest_bump() -> string {
  if shq("grep -rhqE '^bump:[[:space:]]*major' --include='*.md' --exclude='README.md' changes 2>/dev/null") { return "major" }
  if shq("grep -rhqE '^bump:[[:space:]]*minor' --include='*.md' --exclude='README.md' changes 2>/dev/null") { return "minor" }
  if shq("grep -rhqE '^bump:[[:space:]]*patch' --include='*.md' --exclude='README.md' changes 2>/dev/null") { return "patch" }
  return ""
}

# cur + a SemVer bump of `level` -> the next version string
function compute_next(cur: pointer, level: pointer) -> pointer {
  let maj = capture_line(`printf '%s' '{cur}' | cut -d. -f1`)
  let min = capture_line(`printf '%s' '{cur}' | cut -d. -f2`)
  let pat = capture_line(`printf '%s' '{cur}' | cut -d. -f3`)
  if (level == "major") { let m2 = capture_line(`expr {maj} + 1`);  return `{m2}.0.0` }
  if (level == "minor") { let n2 = capture_line(`expr {min} + 1`);  return `{maj}.{n2}.0` }
  let p2 = capture_line(`expr {pat} + 1`)
  return `{maj}.{min}.{p2}`
}


# ---- changelog rendering ----------------------------------------------------
#
# One changeset becomes one bullet. The body is markdown and is kept as markdown:
# the previous shell pipeline ran it through `tr '\n' ' '`, which collapsed every
# multi-line changeset into a single paragraph — a nested list came out as a run
# of inline " - " fragments, and a release with a dozen changesets read as one
# unbroken wall. Continuation lines are indented two spaces instead, so nested
# bullets and paragraphs stay inside their bullet.

property Changeset { typ: pointer = "", body: pointer = "" }

# The conventional-commit types, in the order a reader wants them: what is new,
# what is fixed, what got faster, then the housekeeping. A type not listed here
# still gets a group, appended after these in first-seen order.
function type_heading(t: pointer) -> pointer {
  if t == "feat"     { return "Features" }
  if t == "fix"      { return "Fixes" }
  if t == "perf"     { return "Performance" }
  if t == "refactor" { return "Refactoring" }
  if t == "docs"     { return "Documentation" }
  if t == "build"    { return "Build" }
  if t == "ci"       { return "CI" }
  if t == "test"     { return "Tests" }
  if t == "style"    { return "Style" }
  if t == "revert"   { return "Reverts" }
  if t == "chore"    { return "Chores" }
  return title_case(t)
}
function type_rank(t: pointer) -> int {
  if t == "feat"     { return 0 }
  if t == "fix"      { return 1 }
  if t == "perf"     { return 2 }
  if t == "refactor" { return 3 }
  if t == "docs"     { return 4 }
  if t == "build"    { return 5 }
  if t == "ci"       { return 6 }
  if t == "test"     { return 7 }
  if t == "style"    { return 8 }
  if t == "revert"   { return 9 }
  if t == "chore"    { return 10 }
  return 50
}

# strip trailing whitespace from a line
function rstrip(s: pointer) -> pointer {
  var n = slen(s)
  while n > 0 and is_space_all(s[n - 1]) { n -= 1 }
  return sslice(s, 0, n)
}

# Parse one changeset file: the `type:`/`bump:` headers, then everything else as
# the body. Returns a Changeset with an empty body when the file is unreadable.
function read_changeset(path: pointer) -> Changeset {
  let cs = new Changeset
  cs.typ = ""
  cs.body = ""
  let text = read_file(path)
  if text == null { return cs }
  let b = sb_new()
  let n = slen(text)
  var i = 0
  var seen_body = false
  while i < n {
    let ln = line_at(text, i)
    i = i + slen(ln) + 1
    if not seen_body and s_starts(ln, "type:") {
      cs.typ = s_trim(sslice(ln, 5, slen(ln)))
      continue
    }
    if not seen_body and s_starts(ln, "bump:") { continue }
    # a leading blank line between the headers and the body is not body content
    if not seen_body and slen(s_trim(ln)) == 0 { continue }
    seen_body = true
    sb_puts(b, rstrip(ln))
    sb_putc(b, '\n')
  }
  # drop trailing blank lines
  var body = sb_str(b)
  var m = slen(body)
  while m > 0 and is_space_all(body[m - 1]) { m -= 1 }
  cs.body = sslice(body, 0, m)
  if cs.typ == "" { cs.typ = "chore" }
  return cs
}

# Render one changeset as a markdown list item: the first line after "- ", every
# following line indented two spaces so it stays within the item. Blank lines
# stay blank (an indented blank line is just trailing whitespace).
function render_bullet(b: Sb, body: pointer) -> void {
  let n = slen(body)
  var i = 0
  var first = true
  while i < n {
    let ln = line_at(body, i)
    i = i + slen(ln) + 1
    if first { sb_puts(b, "- ");  first = false }
    else if slen(ln) == 0 { sb_putc(b, '\n');  continue }
    else { sb_puts(b, "  ") }
    sb_puts(b, ln)
    sb_putc(b, '\n')
  }
}

# the changesets in `dir`, README.md excluded, in filename order
function load_changesets(dir: pointer) -> []Changeset {
  let out = new []Changeset
  let names = list_sorted(dir)
  var i = 0
  while i < len(names) {
    let nm = names[i]
    i += 1
    if nm == "README.md" { continue }
    if not s_ends(nm, ".md") { continue }
    let cs = read_changeset(`{dir}/{nm}`)
    if slen(cs.body) > 0 { push(out, cs) }
  }
  return out
}

# assemble the CHANGELOG.md section for `ver` from the pending changesets into
# the scratch file rel_section.md: a dated header, then one "### <Heading>"
# group per conventional-commit type, each holding its changesets as bullets.
function render_section(ver: pointer, date: pointer, dir: pointer) -> pointer {
  let sets = load_changesets(dir)
  let b = sb_new()
  sb_puts(b, `## v{ver} — {date}\n`)

  # walk the type groups in rank order, then any unranked type in first-seen order
  let done = new []pointer
  var emitted = 0
  while emitted < len(sets) {
    # pick the lowest-ranked type not yet emitted, ties broken by name
    var best = ""
    var bestrank = 0
    var si = 0
    while si < len(sets) {
      let t = sets[si].typ
      si += 1
      var already = false
      var di = 0
      while di < len(done) { if done[di] == t { already = true };  di += 1 }
      if already { continue }
      let r = type_rank(t)
      if best == "" or r < bestrank or (r == bestrank and str_gt(best, t)) { best = t;  bestrank = r }
    }
    if best == "" { break }
    push(done, best)

    # collect this group's bodies and sort them, so a release is reproducible
    let bodies = new []pointer
    var k = 0
    while k < len(sets) {
      if sets[k].typ == best { push(bodies, sets[k].body) }
      k += 1
    }
    strs_sort(bodies)

    sb_puts(b, `\n### {type_heading(best)}\n\n`)
    var j = 0
    while j < len(bodies) {
      render_bullet(b, bodies[j])
      j += 1
      emitted += 1
    }
  }
  return sb_str(b)
}

function build_section(ver: pointer) -> void {
  let date = capture_line("date +%Y-%m-%d")
  write_file(tmp_path("rel_section.md"), render_section(ver, date, "changes"))
}

# ludic-dev changelog-render <version> <date> <dir> — print the CHANGELOG section that
# `dir`'s changesets would produce. Used to re-render the sections of releases
# cut before the renderer preserved markdown structure: check the changesets out
# of the tag's parent commit, point this at them, and splice the result back in.
function cmd_changelog_render() -> int {
  if arg_count() < 5 {
    err("usage: ludic-dev changelog-render <version> <date> <changesets-dir>\n")
    return 1
  }
  out(render_section(arg(2), arg(3), arg(4)))
  return 0
}

# prepend the scratch rel_section.md into CHANGELOG.md, above the first existing
# release section (or at the end of the header if this is the first release).
function prepend_changelog() -> void {
  if not file_exists("CHANGELOG.md") {
    shell("printf '# Changelog\n\nAll notable changes to the Ludic toolchain, newest first. Generated from the\nchangesets under changes/ by ludic-dev release; do not edit released sections by hand.\n\n' > CHANGELOG.md")
  }
  let ln = capture_line("grep -n '^## ' CHANGELOG.md | head -1 | cut -d: -f1")
  if (ln == "") {
    shell(`cat CHANGELOG.md {tmp_dir()}/rel_section.md > {tmp_dir()}/rel_new.md`)
  } else {
    shell(`head -n $(expr {ln} - 1) CHANGELOG.md > {tmp_dir()}/rel_new.md`)
    shell(`cat {tmp_dir()}/rel_section.md >> {tmp_dir()}/rel_new.md`)
    shell(`tail -n +{ln} CHANGELOG.md >> {tmp_dir()}/rel_new.md`)
  }
  shell(`cp {tmp_dir()}/rel_new.md CHANGELOG.md`)
}

# ---- release artifacts + publishing -----------------------------------------

# Extract one release's section out of CHANGELOG.md: everything from its
# "## vX.Y.Z" heading up to the next "## " heading. This is what a release's
# notes are — the notes and the changelog can then never disagree.
function changelog_section(ver: pointer) -> pointer {
  let text = read_file("CHANGELOG.md")
  if text == null { return "" }
  let head = `## v{ver} `
  let n = slen(text)
  var i = 0
  var start = -1
  while i < n {
    let ln = line_at(text, i)
    let next = i + slen(ln) + 1
    if start < 0 {
      if s_starts(ln, head) { start = i }
    } else {
      if s_starts(ln, "## ") { return sslice(text, start, i) }
    }
    i = next
  }
  if start < 0 { return "" }
  return sslice(text, start, n)
}

# ludic-dev changelog-section <version> — print that release's CHANGELOG section.
function cmd_changelog_section() -> int {
  if arg_count() < 3 { err("usage: ludic-dev changelog-section <version>\n");  return 1 }
  let sec = changelog_section(arg(2))
  if slen(sec) == 0 { err(`changelog-section: no section for v{arg(2)} in CHANGELOG.md\n`);  return 1 }
  out(sec)
  return 0
}

# the platform's SHA-256 tool (coreutils on Linux, shasum on macOS)
function sha256_cmd() -> pointer {
  if shq("command -v sha256sum >/dev/null 2>&1") { return "sha256sum" }
  return "shasum -a 256"
}

# Build the release artifacts into dist/: a reproducible source+seed tarball from
# the tag, a ready-to-run toolchain built on this host, and one `.sha256` beside
# each — a release without checksums asks everyone downstream to trust the
# transport.
#
# The toolchain tarball is a complete install root, not just binaries: bin/ next
# to the engine runtime, the bundled ludic.* packages and VERSION, laid out
# exactly as ludic_home() expects. install.sh unpacks it and is done; anything
# missing here is a game that will not link on a machine with no checkout.
#
# The checksums are per-artifact rather than a single SHA256SUMS on purpose. A
# release is assembled from more than one host (a Linux runner cannot build the
# macOS toolchain), and `forgejo_upload_assets` skips an asset whose name is
# already attached — so a shared SHA256SUMS would be written by whichever host
# published first and would then never cover anything added later. One file per
# artifact has a unique name, so each host's contribution stands on its own.
#
#   shasum -a 256 -c ludic-X.Y.Z-src.tar.gz.sha256
function build_artifacts(ver: pointer) -> bool {
  shell("rm -rf dist && mkdir -p dist")
  if not shq(`git archive --format=tar.gz --prefix=ludic-{ver}/ -o dist/ludic-{ver}-src.tar.gz v{ver}`) {
    err(`release: git archive of v{ver} failed (is the tag present?)\n`)
    return false
  }
  if is_exec("bin/ludicc") {
    let plat = capture_line("uname -s | tr '[:upper:]' '[:lower:]'")
    let arch = capture_line("uname -m")
    let name = `ludic-{ver}-{plat}-{arch}`
    let stage = `{tmp_dir()}/{name}`
    shell(`rm -rf {stage} && mkdir -p {stage}/bin`)
    if not shq(`cp bin/ludic bin/ludicc bin/ludic-fmt bin/ludic-lsp bin/ludic-ui-preview {stage}/bin/`) {
      err("release: the toolchain is not built (run: ludic-dev build)\n")
      return false
    }
    shell(`cp -R runtime {stage}/runtime`)
    shell(`cp -R packages {stage}/packages`)
    # the language reference: ludic-lsp indexes it for hover and go-to-definition
    # on built-ins (docs/language/**.md, ~4 MB of markdown)
    shell(`mkdir -p {stage}/docs && cp -R docs/language {stage}/docs/language`)
    shell(`cp VERSION LICENSE README.md {stage}/`)
    # the Linux link needs the Darwin-stdio shim injected through $LUDIC_CC; it
    # travels with the toolchain that needs it (see tools/ci/linux_stdio_shim.ll).
    if plat == "linux" { shell(`mkdir -p {stage}/lib && cp tools/ci/linux_stdio_shim.ll {stage}/lib/`) }
    if not shq(`tar -czf dist/{name}.tar.gz -C {tmp_dir()} {name}`) {
      err("release: building the toolchain tarball failed\n")
      return false
    }
    shell(`rm -rf {stage}`)
  }
  if not shq(`cd dist && for f in *.tar.gz; do {sha256_cmd()} "$f" > "$f.sha256" || exit 1; done`) {
    err("release: writing the per-artifact .sha256 files failed\n")
    return false
  }
  shell("ls -l dist")
  return true
}

# ludic-dev publish [vX.Y.Z] — publish an already-tagged release: build the artifacts,
# take the notes from that version's CHANGELOG section, and create the Forgejo
# release. Defaults to the version in VERSION. This is what CI runs on a tag
# push, and what `ludic-dev release --publish` calls once it has tagged.
function publish_tag(ver: pointer) -> int {
  if getenv_or("FORGEJO_TOKEN", "") == "" { err("publish: set FORGEJO_TOKEN (a Forgejo access token)\n");  return 1 }
  let body = tmp_path("rel_notes.md")
  let sec = changelog_section(ver)
  if slen(sec) == 0 { err(`publish: no CHANGELOG section for v{ver}\n`);  return 1 }
  write_file(body, sec)
  if not build_artifacts(ver) { return 1 }
  if forgejo_publish(`v{ver}`, body, "dist") != 0 {
    err("publish: creating the Forgejo release failed\n")
    return 1
  }
  return 0
}

function cmd_publish() -> int {
  var ver = read_version_or("")
  if arg_count() >= 3 {
    var a = arg(2)
    if s_starts(a, "v") { a = sslice(a, 1, slen(a)) }
    ver = a
  }
  if ver == "" { err("publish: no version given and no VERSION file\n");  return 1 }
  return publish_tag(ver)
}

# push main + the tag and create the Forgejo release with build artifacts.
function publish_release(ver: pointer) -> int {
  if getenv_or("FORGEJO_TOKEN", "") == "" { err("release --publish: set FORGEJO_TOKEN (a Forgejo access token)\n"); return 1 }
  if not shq("git push origin HEAD") { err("release: git push (main) failed\n"); return 1 }
  if not shq(`git push origin v{ver}`) { err("release: git push (tag) failed\n"); return 1 }
  return publish_tag(ver)
}

function cmd_release() -> int {
  # parse args: an optional level positional, and a --publish flag
  var level = ""
  var publish = false
  var dry = false
  var ai = 2
  while ai < arg_count() {
    let a = arg(ai)
    if (a == "--publish") { publish = true }
    else { if (a == "--dry-run") { dry = true }
    else { if (a == "major") or (a == "minor") or (a == "patch") { level = a }
    else { err(`release: unknown argument {a}\n`); return 1 } } }
    ai += 1
  }

  if not has_changesets() {
    err("release: no changesets under changes/ — add one (see changes/README.md)\n"); return 1
  }
  if (level == "") { level = highest_bump() }
  if (level == "") { err("release: no bump: level in any changeset\n"); return 1 }

  let cur = read_version_or("0.0.0")
  let ver = compute_next(cur, level)
  print(`releasing v{ver}  ({level} bump from {cur})`)

  build_section(ver)
  # --dry-run stops here: the section is rendered to stdout and nothing on disk,
  # in git, or on the remote is touched. This is the cheap way to read a release
  # before cutting it, which the old all-or-nothing command had no answer for.
  if dry {
    print("")
    let sec = read_file(tmp_path("rel_section.md"))
    if sec != null { out(sec) }
    print("")
    print(`  dry run — nothing written. cut it with: ludic-dev release {level}`)
    return 0
  }
  prepend_changelog()
  if not write_file("VERSION", `{ver}\n`) { err("release: cannot write VERSION\n"); return 1 }
  shell("rm -f $(ls changes/*.md | grep -v '/README.md')")

  # stage only the release artifacts — never a blanket `git add -A`, which would
  # sweep unrelated in-flight edits (this tree is worked on concurrently).
  if not shq("git add VERSION CHANGELOG.md changes") { err("release: git add failed\n"); return 1 }
  if not shq(`git commit -q -m 'chore(release): v{ver}'`) { err("release: git commit failed\n"); return 1 }
  if not shq(`git tag v{ver}`) { err("release: git tag failed (already exists?)\n"); return 1 }
  print(`  committed + tagged v{ver}`)

  if publish { return publish_release(ver) }
  print(`  local release ready. publish with: FORGEJO_TOKEN=… ludic-dev release {level} --publish`)
  print(`  (or push:  git push origin HEAD && git push origin v{ver})`)
  return 0
}