#!/usr/bin/env bash
# Redirect each existing per-component Gitea repo into a branch on the
# canonical RedBear-OS repo, then point the matching git submodule(s) at
# that branch. After this, the per-component Gitea repos can be deleted
# without breaking any submodule resolution.
#
# What this script does, for each per-component Gitea repo:
#   1. Fetches the repo's HEAD into a temp clone.
#   2. Pushes that HEAD as a `submodule/<component>` branch on RedBear-OS.
#   3. Rewrites `.gitmodules` so any submodule entry pointing at the
#      per-component URL now points at RedBear-OS with the new branch.
#
# What it does NOT do:
#   - It does not move source content between repositories (source already
#     lives in the per-component repo; we just push it under a new branch
#     name in the canonical repo).
#   - It does not delete the per-component Gitea repos. Use
#     delete-per-component-repos.sh afterwards.
#   - It does not touch recipe.toml files (none reference the per-component
#     URLs as far as the current tree shows).
#
# Token is read at runtime from $REDBEAR_GITEA_TOKEN (or ~/.netrc). It is
# NEVER written to disk, logged, or echoed.

set -euo pipefail

GITEA_HOST="${GITEA_HOST:-https://gitea.redbearos.org}"
GITEA_USER="${GITEA_USER:-vasilito}"
CANONICAL_REPO="${CANONICAL_REPO:-RedBear-OS}"
CANONICAL_URL="${CANONICAL_URL:-${GITEA_HOST}/${GITEA_USER}/${CANONICAL_REPO}.git}"

# Per-component Gitea repos to redirect. The actual Gitea slug is
# discovered at runtime via the API, so this list contains the canonical
# component names only.
DEFAULT_COMPONENTS=(base kernel installer redox-drm userutils libredox libpciaccess)

DRY_RUN=0
SKIP_PUSH=0
COMPONENTS=()

while [ $# -gt 0 ]; do
    case "$1" in
        --dry-run)   DRY_RUN=1 ;;
        --skip-push) SKIP_PUSH=1 ;;
        -h|--help)   sed -n '2,28p' "$0"; exit 0 ;;
        --) shift; while [ $# -gt 0 ]; do COMPONENTS+=("$1"); shift; done ;;
        -*)  echo "ERROR: unknown arg: $1" >&2; exit 2 ;;
        *)   COMPONENTS+=("$1") ;;
    esac
    shift
done

[ "${#COMPONENTS[@]}" -gt 0 ] || COMPONENTS=("${DEFAULT_COMPONENTS[@]}")

log()  { printf '[redirect-to-submodules] %s\n' "$*" >&2; }
die()  { log "FATAL: $*"; exit 1; }

resolve_token() {
    if [ -n "${REDBEAR_GITEA_TOKEN:-}" ]; then
        printf '%s' "$REDBEAR_GITEA_TOKEN"
        return 0
    fi
    if [ -r "$HOME/.netrc" ]; then
        awk -v host="gitea.redbearos.org" -v user="$GITEA_USER" '
            $1=="machine" && $2==host { in_block=1; next }
            in_block && $1=="login" && $2==user { want=1; next }
            in_block && want && $1=="password" { print $2; exit }
            in_block && $1=="machine" { in_block=0 }
        ' "$HOME/.netrc"
    fi
}

TOKEN="$(resolve_token || true)"
[ -n "$TOKEN" ] || die "no token found. Set REDBEAR_GITEA_TOKEN or configure ~/.netrc."

command -v git >/dev/null || die "git not found in PATH"
command -v jq  >/dev/null || die "jq not found in PATH"
git rev-parse --is-inside-work-tree >/dev/null 2>&1 || die "must be run from inside the ${CANONICAL_REPO} working tree"

current_branch="$(git rev-parse --abbrev-ref HEAD)"
log "Working tree : $(git rev-parse --show-toplevel)"
log "Branch       : ${current_branch}"
log "Canonical URL: ${CANONICAL_URL}"

if [ "$DRY_RUN" -eq 0 ] && [ "$SKIP_PUSH" -eq 0 ]; then
    log ""
    log "This script PUSHES branches to ${CANONICAL_URL} and modifies .gitmodules."
    read -r -p "Type 'redirect' to confirm: " confirm
    [ "$confirm" = "redirect" ] || { log "Aborted."; exit 1; }
fi

api_get() {
    curl -fsS -H "Authorization: token $TOKEN" \
         -H "Accept: application/json" \
         "$GITEA_HOST/api/v1$1"
}

log "Verifying Gitea credentials ..."
api_get "/user" >/dev/null || die "token rejected by Gitea API"

log "Fetching Gitea repo list ..."
REPO_NAMES_API="$(api_get "/users/${GITEA_USER}/repos?limit=200" | jq -r '.[].name')"
[ -n "${REPO_NAMES_API}" ] || die "no repos returned — check token permissions."

find_slug() {
    local component="$1"
    # Try the legacy redbear-os-<component> convention first, then the bare name.
    for candidate in "redbear-os-${component}" "${component}"; do
        if printf '%s\n' "${REPO_NAMES_API}" | grep -qx "${candidate}"; then
            printf '%s' "${candidate}"
            return 0
        fi
    done
    return 1
}

redirect_component() {
    local component="$1"
    local gitea_slug
    if ! gitea_slug="$(find_slug "${component}")"; then
        log ""
        log "=== ${component} ==="
        die "no Gitea repo found for component '${component}' (tried: redbear-os-${component}, ${component})"
    fi
    local branch="submodule/${component}"

    log ""
    log "=== ${component} ==="
    log "  source Gitea repo : ${gitea_slug}"
    log "  target branch    : ${branch}"

    if [ "$DRY_RUN" -eq 1 ]; then
        log "  [dry-run] would fetch HEAD, push as ${branch}, rewrite .gitmodules"
        return 0
    fi

    local tmp
    tmp="$(mktemp -d)"
    trap 'rm -rf "$tmp"' EXIT

    log "  cloning ${gitea_slug} ..."
    local src_url="https://${TOKEN}@${GITEA_HOST#https://}/${GITEA_USER}/${gitea_slug}.git"
    git clone --quiet "${src_url}" "${tmp}/src" \
        || die "clone failed for ${gitea_slug}"

    local src_default
    src_default="$(git -C "${tmp}/src" symbolic-ref --short HEAD 2>/dev/null || echo "")"
    local src_commit_count
    src_commit_count="$(git -C "${tmp}/src" rev-list --all --count 2>/dev/null || echo 0)"
    if [ -z "${src_commit_count}" ] || [ "${src_commit_count}" = "0" ]; then
        log "  source repo is empty (0 commits) — skipping push"
        rm -rf "${tmp}"
        trap - EXIT
        log "  ✓ ${component} (no-op)"
        return 0
    fi
    log "  source default branch: ${src_default} (${src_commit_count} commits)"
    log "  pushing ${branch} to ${CANONICAL_URL} ..."
    local push_url="https://${TOKEN}@${GITEA_HOST#https://}/${GITEA_USER}/${CANONICAL_REPO}.git"
    git -C "${tmp}/src" push --quiet "${push_url}" "refs/heads/${src_default}:refs/heads/${branch}" \
        || die "push failed for ${branch}"

    log "  rewriting .gitmodules ..."
    if grep -q "url = .*${gitea_slug}\.git" .gitmodules 2>/dev/null; then
        sed -i.bak "s|url = .*${gitea_slug}\.git|url = ${CANONICAL_URL}|" .gitmodules
        sed -i "s|^	branch = .*|	branch = ${branch}|" .gitmodules
        rm -f .gitmodules.bak
        log "  updated"
    else
        log "  no .gitmodules entry references ${gitea_slug}; left untouched"
    fi

    rm -rf "${tmp}"
    trap - EXIT
    log "  ✓ ${component} redirected"
}

for c in "${COMPONENTS[@]}"; do
    redirect_component "$c"
done

log ""
log "Done. Verify with: git submodule status"
log "Then run ./local/scripts/delete-per-component-repos.sh to delete the"
log "now-unused per-component repos on Gitea."