#!/usr/bin/env bash
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
WORKSPACE_ROOT="${1:-$(cd "$SCRIPT_DIR/../../../.." && pwd)}"
SINCE="${2:-7 days ago}"
UNTIL="${3:-}"
EXCLUDES_FILE="$WORKSPACE_ROOT/.workspace-ops/config/target-excludes.txt"

if [[ "$WORKSPACE_ROOT" != "/" ]]; then
  WORKSPACE_ROOT="${WORKSPACE_ROOT%/}"
fi

normalized_excludes() {
  local exclude

  [[ -f "$EXCLUDES_FILE" ]] || return 0

  while IFS= read -r exclude || [[ -n "$exclude" ]]; do
    exclude="${exclude%%#*}"
    exclude="${exclude#"${exclude%%[![:space:]]*}"}"
    exclude="${exclude%"${exclude##*[![:space:]]}"}"
    exclude="${exclude#./}"
    exclude="${exclude#/}"
    exclude="${exclude%/}"

    [[ -z "$exclude" ]] && continue

    printf '%s\n' "$exclude"
  done < "$EXCLUDES_FILE"
}

is_excluded_repo() {
  local rel="$1"
  local exclude

  while IFS= read -r exclude; do
    if [[ "$rel" == "$exclude" || "$rel" == "$exclude/"* ]]; then
      return 0
    fi
  done < <(normalized_excludes)

  return 1
}

repo_paths() {
  local -a find_args=(
    "$WORKSPACE_ROOT"
    -path "$WORKSPACE_ROOT/.git" -prune -o
    -path "$WORKSPACE_ROOT/.workspace-ops" -prune -o
    -path "$WORKSPACE_ROOT/.tmp" -prune -o
    -path "$WORKSPACE_ROOT/.antigravitycli" -prune -o
    -path "*/.agent-cache" -prune -o
    -path "*/node_modules" -prune -o
    -path "*/build" -prune -o
    -path "*/dist" -prune -o
    -path "*/.dart_tool" -prune -o
    -path "*/coverage" -prune -o
  )
  local exclude
  local gitdir
  local rel
  local repo

  while IFS= read -r exclude; do
    find_args+=(-path "$WORKSPACE_ROOT/$exclude" -prune -o)
  done < <(normalized_excludes)

  find_args+=(-type d -name .git -print)

  find "${find_args[@]}" |
    sort |
    while IFS= read -r gitdir; do
      repo="$(dirname "$gitdir")"
      rel="${repo#$WORKSPACE_ROOT/}"
      if git -C "$WORKSPACE_ROOT" check-ignore -q -- "$rel" && ! is_excluded_repo "$rel"; then
        printf '%s\n' "$repo"
      fi
    done
}

log_args=(--branches --remotes --since="$SINCE")
if [[ -n "$UNTIL" ]]; then
  log_args+=(--until="$UNTIL")
fi

while IFS= read -r repo; do
  rel="${repo#$WORKSPACE_ROOT/}"

  echo "## $rel"
  printf 'branch: '
  git -C "$repo" branch --show-current

  printf 'commits: '
  git -C "$repo" log "${log_args[@]}" --format='%H' | sort -u | wc -l

  authors="$(git -C "$repo" log "${log_args[@]}" --format='%aN <%aE>' | sort -u)"
  author_count="$(printf '%s\n' "$authors" | awk 'NF {c++} END {print c + 0}')"
  echo "author_count: $author_count"
  echo "authors:"
  if [[ -n "$authors" ]]; then
    printf '%s\n' "$authors" | sed 's/^/- /'
  fi

  echo "subjects:"
  git -C "$repo" log "${log_args[@]}" --date=short --pretty=format:'%h | %ad | %s'
  echo

  echo "top paths:"
  git -C "$repo" log "${log_args[@]}" --name-only --pretty=format:'' |
    awk '
      NF {
        n = split($0, a, "/")
        if (n == 1) {
          p = a[1]
        } else if (a[1] == "agent-task" || a[1] == "agent-roadmap" || a[1] == "agent-ops") {
          p = a[1] "/" a[2]
        } else {
          p = a[1] "/" a[2]
        }
        c[p]++
      }
      END {
        for (p in c) print c[p], p
      }
    ' |
    sort -nr |
    head -n 12

  echo "shortstat:"
  git -C "$repo" log "${log_args[@]}" --shortstat --pretty=tformat: |
    awk '
      /files? changed/ {
        files += $1
        for (i = 1; i <= NF; i++) {
          if ($i == "insertion(+)" || $i == "insertions(+)") ins += $(i - 1)
          if ($i == "deletion(-)" || $i == "deletions(-)") del += $(i - 1)
        }
      }
      END {
        printf "files_changed_sum=%d insertions=%d deletions=%d\n", files, ins, del
      }
    '
  echo
done < <(repo_paths)