import type { TemplateContext } from '../types';

export function generateContextRecovery(ctx: TemplateContext): string {
  const binDir = ctx.host === 'codex' ? '$GSTACK_BIN' : ctx.paths.binDir;

  return `## Context Recovery

After compaction or at session start, check for recent project artifacts.
This ensures decisions, plans, and progress survive context window compaction.

\`\`\`bash
eval "$(${binDir}/gstack-slug 2>/dev/null)"
_PROJ="\${GSTACK_HOME:-$HOME/.gstack}/projects/\${SLUG:-unknown}"
if [ -d "$_PROJ" ]; then
  echo "--- RECENT ARTIFACTS ---"
  # Last 3 artifacts across ceo-plans/ and checkpoints/
  find "$_PROJ/ceo-plans" "$_PROJ/checkpoints" -type f -name "*.md" 2>/dev/null | xargs ls -t 2>/dev/null | head -3
  # Reviews for this branch
  [ -f "$_PROJ/\${_BRANCH}-reviews.jsonl" ] && echo "REVIEWS: $(wc -l < "$_PROJ/\${_BRANCH}-reviews.jsonl" | tr -d ' ') entries"
  # Timeline summary (last 5 events)
  [ -f "$_PROJ/timeline.jsonl" ] && tail -5 "$_PROJ/timeline.jsonl"
  # Cross-session injection
  if [ -f "$_PROJ/timeline.jsonl" ]; then
    _LAST=$(grep "\\"branch\\":\\"\${_BRANCH}\\"" "$_PROJ/timeline.jsonl" 2>/dev/null | grep '"event":"completed"' | tail -1)
    [ -n "$_LAST" ] && echo "LAST_SESSION: $_LAST"
    # Predictive skill suggestion: check last 3 completed skills for patterns
    _RECENT_SKILLS=$(grep "\\"branch\\":\\"\${_BRANCH}\\"" "$_PROJ/timeline.jsonl" 2>/dev/null | grep '"event":"completed"' | tail -3 | grep -o '"skill":"[^"]*"' | sed 's/"skill":"//;s/"//' | tr '\\n' ',')
    [ -n "$_RECENT_SKILLS" ] && echo "RECENT_PATTERN: $_RECENT_SKILLS"
  fi
  _LATEST_CP=$(find "$_PROJ/checkpoints" -name "*.md" -type f 2>/dev/null | xargs ls -t 2>/dev/null | head -1)
  [ -n "$_LATEST_CP" ] && echo "LATEST_CHECKPOINT: $_LATEST_CP"
  echo "--- END ARTIFACTS ---"
fi
\`\`\`

If artifacts are listed, read the most recent one to recover context.

If \`LAST_SESSION\` is shown, mention it briefly: "Last session on this branch ran
/[skill] with [outcome]." If \`LATEST_CHECKPOINT\` exists, read it for full context
on where work left off.

If \`RECENT_PATTERN\` is shown, look at the skill sequence. If a pattern repeats
(e.g., review,ship,review), suggest: "Based on your recent pattern, you probably
want /[next skill]."

**Welcome back message:** If any of LAST_SESSION, LATEST_CHECKPOINT, or RECENT ARTIFACTS
are shown, synthesize a one-paragraph welcome briefing before proceeding:
"Welcome back to {branch}. Last session: /{skill} ({outcome}). [Checkpoint summary if
available]. [Health score if available]." Keep it to 2-3 sentences.`;
}