#!/usr/bin/env bash
# lessons.sh — local-first lesson capture for Larry-Anywhere.
#
# When Bryan teaches Larry something during a session — a correction, a new
# pattern, a gotcha, a site-specific quirk — it gets appended here. Lessons
# stay LOCAL by default; they never auto-leave the client box. When Bryan can
# reach his dev machine again, he runs `lessons.sh export` and copies the
# bundle back to me (the home Larry) so I can commit it into the canonical
# agents/ persona files in the cloverleaf-larry repo.
#
# Storage: $LARRY_HOME/lessons/<YYYY-MM-DD>.md (one file per day, append-only).
#          Plus a journal at $LARRY_HOME/lessons/_index.tsv for machine parsing.
#
# Subcommands:
#   add "text" [--topic X] [--site Y] [--severity info|warn|fix]
#                                       append a lesson
#   list                                 newest first, with index ids
#   show <id>                            one lesson
#   export [--since YYYY-MM-DD]          one big markdown bundle to stdout
#                                        (paste this back to me on your dev machine)
#   export --bundle PATH                 write the bundle to a file
#   export --gh-issue                    format as a GitHub Issue body + open with `gh` if available
#   clear [--before YYYY-MM-DD]          delete uploaded lessons (use after a successful upload)
#   count                                just the number of unbundled lessons
set -o pipefail

LARRY_HOME="${LARRY_HOME:-$HOME/.larry}"
LESSONS_DIR="$LARRY_HOME/lessons"
LESSONS_INDEX="$LESSONS_DIR/_index.tsv"

mkdir -p "$LESSONS_DIR" 2>/dev/null
chmod 700 "$LESSONS_DIR" 2>/dev/null || true

if [ ! -f "$LESSONS_INDEX" ]; then
  printf 'timestamp\tid\ttopic\tsite\tseverity\tfile\n' > "$LESSONS_INDEX"
fi

# v0.7.5: shared CR-safety primitives.  Source if available.
_LESSONS_LIB_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" 2>/dev/null && pwd)"
if [ -r "$_LESSONS_LIB_DIR/cygwin-safe.sh" ]; then
  # shellcheck disable=SC1090,SC1091
  . "$_LESSONS_LIB_DIR/cygwin-safe.sh"
else
  coerce_int() { local r="${1:-}" d="${2:-0}" c; c=$(printf '%s' "$r" | tr -cd '0-9'); printf '%s' "${c:-$d}"; }
fi

die() { printf 'lessons: %s\n' "$*" >&2; exit 1; }

_next_id() {
  local n
  n=$(awk -F'\t' 'NR>1{print $2}' "$LESSONS_INDEX" | sort -n | tail -1)
  # v0.7.5: coerce_int on awk's last-line output — index file may have CRLF
  # if a Windows editor touched it, and `tail -1` would keep the CR.
  printf '%04d' $(( $(coerce_int "$n" 0) + 1 ))
}

cmd_add() {
  local text="$1"; shift
  local topic="" site="" severity="info"
  while [ $# -gt 0 ]; do
    case "$1" in
      --topic)    shift; topic="$1" ;;
      --site)     shift; site="$1" ;;
      --severity) shift; severity="$1" ;;
      *) die "unknown flag: $1" ;;
    esac
    shift
  done
  [ -n "$text" ] || die "lesson text is required"

  local id day file ts
  id=$(_next_id)
  day=$(date +%Y-%m-%d)
  ts=$(date -Iseconds 2>/dev/null || date)
  file="$LESSONS_DIR/${day}.md"

  if [ ! -f "$file" ]; then
    {
      printf '# Lessons captured %s\n\n' "$day"
      printf '_From Larry-Anywhere on %s. Append-only._\n\n' "$(hostname 2>/dev/null || echo unknown)"
    } > "$file"
  fi

  {
    printf '\n## %s — %s' "$id" "$ts"
    [ -n "$topic" ]    && printf ' · **%s**' "$topic"
    [ -n "$site" ]     && printf ' · site=`%s`' "$site"
    [ "$severity" != "info" ] && printf ' · severity=%s' "$severity"
    [ -n "${HCIROOT:-}" ] && printf ' · HCIROOT=`%s`' "$HCIROOT"
    [ -n "${HCISITE:-}" ] && printf ' · HCISITE=`%s`' "$HCISITE"
    printf '\n\n%s\n' "$text"
  } >> "$file"

  printf '%s\t%s\t%s\t%s\t%s\t%s\n' "$ts" "$id" "${topic:-}" "${site:-${HCISITE:-}}" "$severity" "$file" >> "$LESSONS_INDEX"

  printf 'lesson %s captured → %s\n' "$id" "$file"
}

cmd_list() {
  # v0.7.5: coerce_int on wc output (Cygwin CR-taint defense).
  local n; n=$(( $(coerce_int "$(wc -l < "$LESSONS_INDEX")" 0) - 1 ))
  printf 'lessons: %d captured (newest first)\n\n' "$n"
  printf '  id    timestamp                  topic                   site            file\n'
  awk -F'\t' 'NR>1 { lines[++i] = sprintf("  %s  %-26s  %-22s  %-14s  %s", $2, $1, ($3=="" ? "—" : $3), ($4=="" ? "—" : $4), $6) }
              END { for (k=i; k>=1; k--) print lines[k] }' "$LESSONS_INDEX"
}

cmd_show() {
  local id="$1"
  [ -n "$id" ] || die "usage: lessons.sh show <id>"
  local file ts topic
  awk -F'\t' -v id="$id" 'NR>1 && $2==id { print; exit }' "$LESSONS_INDEX" \
    | { IFS=$'\t' read -r ts iid topic site sev file
        [ -z "$file" ] && { die "no such lesson id: $id"; }
        printf '## %s (%s)\n  topic: %s · site: %s · severity: %s · file: %s\n\n' \
          "$id" "$ts" "${topic:-—}" "${site:-—}" "$sev" "$file"
        awk -v marker="## $id" '
          $0 ~ marker, /^## [0-9]{4} —/ { if (NR>1 && /^## [0-9]{4} —/ && $0 !~ marker) exit; print }
        ' "$file"
      }
}

cmd_export() {
  local since="" out="" mode="stdout"
  while [ $# -gt 0 ]; do
    case "$1" in
      --since)     shift; since="$1" ;;
      --bundle)    shift; out="$1"; mode="file" ;;
      --gh-issue)  mode="gh-issue" ;;
      *) die "unknown flag: $1" ;;
    esac
    shift
  done

  local tmp; tmp=$(mktemp)
  {
    printf '# Larry-Anywhere lesson bundle\n\n'
    printf 'Generated: %s\n' "$(date -Iseconds 2>/dev/null || date)"
    printf 'Source: `%s` (host `%s`)\n\n' "$LESSONS_DIR" "$(hostname 2>/dev/null || echo unknown)"
    printf 'Send this back to home-Larry (paste into chat) so it can be committed\n'
    printf 'to the canonical agents/ persona files in cloverleaf-larry.\n\n'
    printf '%s\n\n' '---'

    # Walk files newest-first, optionally filtered by --since
    find "$LESSONS_DIR" -maxdepth 1 -name '*.md' -type f 2>/dev/null \
      | sort -r \
      | while IFS= read -r f; do
          local day; day=$(basename "$f" .md)
          if [ -n "$since" ] && [ "$day" \< "$since" ]; then continue; fi
          cat "$f"
          printf '\n---\n\n'
        done
  } > "$tmp"

  case "$mode" in
    stdout)   cat "$tmp"; rm -f "$tmp" ;;
    file)     mv "$tmp" "$out"; printf 'wrote bundle to %s\n' "$out" >&2 ;;
    gh-issue)
      if command -v gh >/dev/null 2>&1; then
        gh issue create --repo bojj27/cloverleaf-larry \
          --title "Lessons from $(hostname 2>/dev/null) — $(date +%Y-%m-%d)" \
          --body-file "$tmp" \
          --label "lessons" 2>&1
        rm -f "$tmp"
      else
        printf 'gh not installed — falling back to stdout. Copy this body into a manual Issue:\n\n' >&2
        cat "$tmp"
        rm -f "$tmp"
      fi
      ;;
  esac
}

cmd_clear() {
  local before=""
  while [ $# -gt 0 ]; do
    case "$1" in
      --before) shift; before="$1" ;;
      *) die "unknown flag: $1" ;;
    esac
    shift
  done

  local files; files=$(find "$LESSONS_DIR" -maxdepth 1 -name '*.md' -type f 2>/dev/null | sort)
  [ -n "$files" ] || { echo "no lesson files to clear"; return 0; }

  if [ -z "$before" ]; then
    printf 'clear ALL lesson files? '
    printf '%s\n' "$files" | sed 's/^/  /'
    printf 'proceed? [y/N]: '
    read -r ans </dev/tty || ans=""
    # v0.7.5: strip CR so `Y\r` from a Cygwin pty matches `^[Yy]$`.
    ans="${ans//$'\r'/}"
    [[ "$ans" =~ ^[Yy]$ ]] || { echo "aborted"; return 1; }
    printf '%s\n' "$files" | xargs rm -f
    # Reset index but keep header
    head -1 "$LESSONS_INDEX" > "$LESSONS_INDEX.new"
    mv "$LESSONS_INDEX.new" "$LESSONS_INDEX"
    echo "cleared all lesson files"
  else
    printf 'clear lesson files BEFORE %s? files matched:\n' "$before"
    local matched
    matched=$(printf '%s\n' "$files" | while IFS= read -r f; do
      local day; day=$(basename "$f" .md)
      [ "$day" \< "$before" ] && echo "$f"
    done)
    [ -z "$matched" ] && { echo "(none)"; return 0; }
    printf '%s\n' "$matched" | sed 's/^/  /'
    printf 'proceed? [y/N]: '
    read -r ans </dev/tty || ans=""
    # v0.7.5: strip CR so `Y\r` from a Cygwin pty matches `^[Yy]$`.
    ans="${ans//$'\r'/}"
    [[ "$ans" =~ ^[Yy]$ ]] || { echo "aborted"; return 1; }
    printf '%s\n' "$matched" | xargs rm -f
    # Trim index entries
    awk -F'\t' -v before="$before" 'NR==1 || $1 >= before' "$LESSONS_INDEX" > "$LESSONS_INDEX.new"
    mv "$LESSONS_INDEX.new" "$LESSONS_INDEX"
    echo "cleared lesson files before $before"
  fi
}

cmd_count() {
  # v0.7.5: coerce_int on wc output (Cygwin CR-taint defense).
  local n; n=$(( $(coerce_int "$(wc -l < "$LESSONS_INDEX")" 0) - 1 ))
  echo "$n"
}

case "${1:-list}" in
  add)    shift; [ $# -ge 1 ] || die "usage: lessons.sh add \"text\" [--topic X --site Y --severity Z]"; text="$1"; shift; cmd_add "$text" "$@" ;;
  list)   cmd_list ;;
  show)   shift; cmd_show "${1:-}" ;;
  export) shift; cmd_export "$@" ;;
  clear)  shift; cmd_clear "$@" ;;
  count)  cmd_count ;;
  -h|--help|help) sed -n '2,30p' "$0" ;;
  *)      die "unknown subcommand: ${1:-}" ;;
esac