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

# ─────────────────────────────────────────────────────────────────────
# Mobile AI Assets Installer
#
# One script to install skills, agents, and instructions.
# Works both locally (cloned repo) and remotely (curl, no clone).
#
# Local:   ./assets/setup.sh agents
# Remote:  export ASSETS_BASE_URL="https://..."
#          bash <(curl -fsSL "$ASSETS_BASE_URL/setup.sh") agents
# ─────────────────────────────────────────────────────────────────────

VERSION="1.0.0"

# ── Configuration (override with env vars) ───────────────────────────
ASSETS_BASE_URL="${ASSETS_BASE_URL:-}"
AGENTS_DIR="${AGENTS_DIR:-$HOME/.copilot/agents}"
INSTRUCTIONS_DIR="${INSTRUCTIONS_DIR:-./instructions}"

# ── Colors ───────────────────────────────────────────────────────────
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
BOLD='\033[1m'
NC='\033[0m'

# ── Helpers ──────────────────────────────────────────────────────────
info()    { printf "${BLUE}▸${NC} %s\n" "$*"; }
ok()      { printf "${GREEN}✓${NC} %s\n" "$*"; }
warn()    { printf "${YELLOW}!${NC} %s\n" "$*"; }
fail()    { printf "${RED}✗${NC} %s\n" "$*" >&2; exit 1; }
heading() { printf "\n${BOLD}── %s ──${NC}\n" "$*"; }

# ── Mode Detection ───────────────────────────────────────────────────
# Detect if running from a cloned repo or remotely via curl.
MODE=""
ASSETS_DIR=""

detect_mode() {
  local script_dir
  script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" 2>/dev/null && pwd)" || script_dir=""

  if [[ -n "$script_dir" && -f "$script_dir/agents.list" ]]; then
    MODE="local"
    ASSETS_DIR="$script_dir"
  elif [[ -n "$ASSETS_BASE_URL" ]]; then
    MODE="remote"
  else
    fail "Set ASSETS_BASE_URL to run without a clone. Example:
  export ASSETS_BASE_URL=\"https://gitlab.com/org/repo/-/raw/main/assets\"
  bash <(curl -fsSL \"\$ASSETS_BASE_URL/setup.sh\") agents"
  fi
}

# ── Fetch / Download ────────────────────────────────────────────────
# Read a file from the local clone or download it from the remote URL.
fetch() {
  local path="$1"
  if [[ "$MODE" == "local" ]]; then
    cat "$ASSETS_DIR/$path"
  else
    curl -fsSL "$ASSETS_BASE_URL/$path"
  fi
}

# Download a file to a destination path.
download_to() {
  local src="$1" dest="$2"
  mkdir -p "$(dirname "$dest")"
  if [[ "$MODE" == "local" ]]; then
    cp "$ASSETS_DIR/$src" "$dest"
  else
    curl -fsSL "$ASSETS_BASE_URL/$src" -o "$dest"
  fi
}

# ── Commands ─────────────────────────────────────────────────────────

# -- skills [platform] ------------------------------------------------
cmd_skills() {
  local platform="${1:-shared}"
  local manifest="${platform}-skills.yaml"

  heading "Skills ($platform)"

  local yaml
  yaml="$(fetch "$manifest")" || fail "Could not fetch $manifest"

  local installs
  installs=$(echo "$yaml" | sed -n 's/^[[:space:]]*install:[[:space:]]*//p' | sed 's/^"//;s/"$//')

  if [[ -z "$installs" ]]; then
    warn "No install entries in $manifest — nothing to do."
    return 0
  fi

  local count=0
  while IFS= read -r entry; do
    [[ -z "$entry" ]] && continue
    read -r -a args <<< "$entry"
    info "npx skills add ${args[*]}"
    npx skills add "${args[@]}"
    count=$((count + 1))
  done <<< "$installs"

  ok "$count skill(s) installed. Restart your editor if they don't appear."
}

# -- agents ------------------------------------------------------------
cmd_agents() {
  heading "Agents → $AGENTS_DIR"

  local list
  list="$(fetch "agents.list")" || fail "Could not fetch agents.list"

  mkdir -p "$AGENTS_DIR"

  local count=0
  while IFS= read -r file; do
    [[ -z "$file" || "$file" == \#* ]] && continue
    info "$file"
    download_to "agents/$file" "$AGENTS_DIR/$file"
    count=$((count + 1))
  done <<< "$list"

  ok "$count agent(s) installed."
}

# -- instructions ------------------------------------------------------
cmd_instructions() {
  heading "Instructions → $INSTRUCTIONS_DIR"

  local list
  list="$(fetch "instructions.list")" || fail "Could not fetch instructions.list"

  mkdir -p "$INSTRUCTIONS_DIR"

  local count=0
  while IFS= read -r file; do
    [[ -z "$file" || "$file" == \#* ]] && continue
    info "$file"
    download_to "instructions/$file" "$INSTRUCTIONS_DIR/$file"
    count=$((count + 1))
  done <<< "$list"

  ok "$count instruction(s) installed."
}

# -- all [platform] ----------------------------------------------------
cmd_all() {
  local platform="${1:-shared}"
  cmd_skills "$platform"
  cmd_agents
  cmd_instructions
  printf "\n"
  ok "All done."
}

# -- update-lists (local only) -----------------------------------------
# Regenerate agents.list and instructions.list from directory contents.
cmd_update_lists() {
  if [[ "$MODE" != "local" ]]; then
    fail "update-lists only works from a cloned repo."
  fi

  heading "Updating manifests"

  # agents.list
  local agents_dir="$ASSETS_DIR/agents"
  if [[ -d "$agents_dir" ]]; then
    find "$agents_dir" -maxdepth 1 -type f -name '*.agent.md' \
      | xargs -I{} basename {} \
      | sort > "$ASSETS_DIR/agents.list"
    ok "agents.list  → $(wc -l < "$ASSETS_DIR/agents.list" | tr -d ' ') file(s)"
  else
    warn "No agents/ directory found — skipping."
  fi

  # instructions.list
  local instr_dir="$ASSETS_DIR/instructions"
  if [[ -d "$instr_dir" ]]; then
    find "$instr_dir" -maxdepth 1 -type f -name '*.instructions.md' \
      | xargs -I{} basename {} \
      | sort > "$ASSETS_DIR/instructions.list"
    ok "instructions.list → $(wc -l < "$ASSETS_DIR/instructions.list" | tr -d ' ') file(s)"
  else
    warn "No instructions/ directory found — skipping."
  fi
}

# -- help --------------------------------------------------------------
cmd_help() {
  cat <<EOF

${BOLD}Mobile AI Assets Installer${NC} v${VERSION}

${BOLD}USAGE${NC}
  setup.sh <command> [platform]

${BOLD}COMMANDS${NC}
  skills [platform]   Install skills from a curated list
  agents              Install all agent prompt files
  instructions        Install all instruction files
  all [platform]      Install everything at once
  update-lists        Regenerate agents.list / instructions.list (local only)
  help                Show this message

${BOLD}PLATFORMS${NC} (for skills)
  ios        iOS-specific skills
  android    Android-specific skills
  shared     Cross-platform skills (default)

${BOLD}EXAMPLES${NC}
  ${GREEN}# Cloned repo${NC}
  ./assets/setup.sh skills ios
  ./assets/setup.sh agents
  ./assets/setup.sh all ios

  ${GREEN}# No clone — run directly from the remote repo${NC}
  export ASSETS_BASE_URL="https://gitlab.com/org/repo/-/raw/main/assets"
  bash <(curl -fsSL "\$ASSETS_BASE_URL/setup.sh") skills ios
  bash <(curl -fsSL "\$ASSETS_BASE_URL/setup.sh") agents
  bash <(curl -fsSL "\$ASSETS_BASE_URL/setup.sh") all ios

${BOLD}ENVIRONMENT VARIABLES${NC}
  ASSETS_BASE_URL      Base URL for remote downloads (required without clone)
  AGENTS_DIR           Install location for agents   (default: ~/.copilot/agents)
  INSTRUCTIONS_DIR     Install location for instructions (default: ./instructions)
  SKILLS_FILE          Override the skills YAML path  (local mode only)

EOF
}

# ── Main ─────────────────────────────────────────────────────────────
detect_mode

case "${1:-help}" in
  skills)        cmd_skills "${2:-shared}" ;;
  agents)        cmd_agents ;;
  instructions)  cmd_instructions ;;
  all)           cmd_all "${2:-shared}" ;;
  update-lists)  cmd_update_lists ;;
  help|--help|-h) cmd_help ;;
  *)             fail "Unknown command: $1. Run 'setup.sh help' for usage." ;;
esac