#!/usr/bin/env bash
# scripts/release.sh — Automate version bump, changelog, git tag, and push
#
# Usage:
#   bash scripts/release.sh patch          # 1.31.0 → 1.31.1
#   bash scripts/release.sh minor          # 1.31.0 → 1.32.0
#   bash scripts/release.sh major          # 1.31.0 → 2.0.0
#   bash scripts/release.sh 1.32.0         # explicit version
#   bash scripts/release.sh v1.32.0        # with v prefix

set -euo pipefail
cd "$(dirname "$0")/.."

RED='\033[0;31m'; GREEN='\033[0;32m'; YELLOW='\033[1;33m'; BLUE='\033[0;34m'; BOLD='\033[1m'; NC='\033[0m'
info()  { echo -e "${BLUE}▶  $*${NC}"; }
ok()    { echo -e "${GREEN}✓  $*${NC}"; }
warn()  { echo -e "${YELLOW}⚠  $*${NC}"; }
die()   { echo -e "${RED}✗  $*${NC}" >&2; exit 1; }
hr()    { echo -e "${BLUE}────────────────────────────────────────${NC}"; }

# ── Prerequisites ─────────────────────────────────────────────────────────────

command -v cargo  >/dev/null 2>&1 || die "cargo not found"
command -v python3 >/dev/null 2>&1 || die "python3 not found"

# ── Current version ───────────────────────────────────────────────────────────

current=$(grep '^version' Cargo.toml | head -1 | sed 's/.*"\(.*\)".*/\1/')
[[ -n "$current" ]] || die "Could not parse version from Cargo.toml"
info "Current version: ${BOLD}$current${NC}"

# ── Compute new version ───────────────────────────────────────────────────────

bump="${1:-patch}"
IFS='.' read -r major minor patch_v <<< "$current"

case "$bump" in
  major)   new="${major+1}.0.0"; new="$((major + 1)).0.0" ;;
  minor)   new="${major}.$((minor + 1)).0" ;;
  patch)   new="${major}.${minor}.$((patch_v + 1))" ;;
  v*.*.*)  new="${bump#v}" ;;
  *.*.*)   new="$bump" ;;
  *)       die "Usage: $0 [patch|minor|major|X.Y.Z]" ;;
esac

# Validate semver
[[ "$new" =~ ^[0-9]+\.[0-9]+\.[0-9]+$ ]] || die "Invalid version: $new"

hr
info "Releasing: ${BOLD}$current → $new${NC}"
hr

# ── Confirm ───────────────────────────────────────────────────────────────────

read -rp "Proceed with release v${new}? [y/N] " confirm
[[ "$confirm" =~ ^[Yy]$ ]] || die "Aborted"

# ── Check git state ───────────────────────────────────────────────────────────

info "Checking git state..."
if ! git diff --quiet 2>/dev/null || ! git diff --cached --quiet 2>/dev/null; then
  die "Working tree has uncommitted changes — commit or stash first"
fi
current_branch=$(git rev-parse --abbrev-ref HEAD)
info "Branch: $current_branch"

# Check tag doesn't already exist
if git rev-parse "v${new}" >/dev/null 2>&1; then
  die "Tag v${new} already exists"
fi
ok "Git state clean"

# ── 1. Bump Cargo.toml ────────────────────────────────────────────────────────

info "Bumping Cargo.toml..."
if [[ "$(uname)" == "Darwin" ]]; then
  sed -i '' "s/^version = \"${current}\"/version = \"${new}\"/" Cargo.toml
else
  sed -i "s/^version = \"${current}\"/version = \"${new}\"/" Cargo.toml
fi

# Update Cargo.lock
cargo metadata --no-deps --format-version 1 >/dev/null 2>&1 || true
ok "Cargo.toml → $new"

# ── 2. Update server.json ─────────────────────────────────────────────────────

info "Updating server.json..."
NEW_VERSION="$new" python3 - <<'PYEOF'
import json, os, re, sys

version = os.environ['NEW_VERSION']

with open('server.json') as f:
    data = json.load(f)

data['version'] = version

for pkg in data.get('packages', []):
    pkg['version'] = version
    # Update download URL to point at new version tag
    if 'identifier' in pkg:
        pkg['identifier'] = re.sub(
            r'/v[0-9]+\.[0-9]+\.[0-9]+/',
            f'/v{version}/',
            pkg['identifier']
        )
    # SHA256 is computed by CI after building — placeholder signals this
    pkg['fileSha256'] = 'TBD_CI_WILL_UPDATE'

with open('server.json', 'w') as f:
    json.dump(data, f, indent=2)
    f.write('\n')

print(f"  server.json version={version}, identifier URL updated")
PYEOF
ok "server.json → $new (SHA256 updated by CI)"

# ── 3. Generate CHANGELOG entry ───────────────────────────────────────────────

info "Generating CHANGELOG entry..."
prev_tag=$(git describe --tags --abbrev=0 2>/dev/null || echo "")
today=$(date +%Y-%m-%d)

{
  echo "## [$new] — $today"
  echo ""
  if [[ -n "$prev_tag" ]]; then
    git log "${prev_tag}..HEAD" --pretty=format:"- %s" --no-merges \
      | grep -v "^- ci:" \
      | grep -v "^- chore:" \
      | grep -v "^$" \
      || echo "- Minor improvements and bug fixes"
  else
    echo "- Initial public release"
  fi
  echo ""
} > /tmp/release_entry.md

if [[ -f CHANGELOG.md ]]; then
  # Insert after the first header line
  tmp=$(mktemp)
  head -1 CHANGELOG.md > "$tmp"
  echo "" >> "$tmp"
  cat /tmp/release_entry.md >> "$tmp"
  tail -n +2 CHANGELOG.md >> "$tmp"
  mv "$tmp" CHANGELOG.md
else
  {
    echo "# Changelog"
    echo ""
    cat /tmp/release_entry.md
  } > CHANGELOG.md
fi
rm -f /tmp/release_entry.md
ok "CHANGELOG.md updated"

# ── 4. Verify build compiles ──────────────────────────────────────────────────

info "Verifying build (cargo check)..."
cargo check --quiet 2>&1 || die "cargo check failed — fix errors before releasing"
ok "Build check passed"

# ── 5. Commit ─────────────────────────────────────────────────────────────────

info "Creating release commit..."
git add Cargo.toml Cargo.lock server.json CHANGELOG.md
git commit -m "release: v${new}

- Version bump ${current} → ${new}
- server.json identifier URL updated (SHA256 set by CI after build)
- CHANGELOG.md updated"
ok "Release commit created"

# ── 6. Tag ────────────────────────────────────────────────────────────────────

info "Creating annotated tag v${new}..."
git tag -a "v${new}" -m "Release v${new}"
ok "Tagged v${new}"

# ── 7. Push ───────────────────────────────────────────────────────────────────

info "Pushing to GitHub..."
git push origin "$current_branch"
git push origin "v${new}"
ok "Pushed — GitHub Actions triggered"

# ── Done ──────────────────────────────────────────────────────────────────────

hr
echo ""
echo -e "${GREEN}${BOLD}  Release v${new} kicked off!${NC}"
echo ""
echo -e "  Actions:  https://github.com/masdevid/mt5-quant/actions"
echo -e "  Release:  https://github.com/masdevid/mt5-quant/releases/tag/v${new}"
echo ""
echo -e "  ${YELLOW}CI will compute the MCP package SHA256 and${NC}"
echo -e "  ${YELLOW}commit it back to server.json automatically.${NC}"
echo ""
hr