#!/usr/bin/env bash
# update.sh — Full uplift cycle for claude-skills on Linux/macOS (and git-bash on Windows)
#
# Steps:
#   1. git pull --ff-only in claude-skills repo
#   2. Conditionally rebuild projects-meta-mcp (if source changed)
#   3. Conditionally rebuild interns-mcp (if source changed)
#   4. Install all skills via install.sh
#   5. Show version diff (before → after)
#   6. Print reload hints
#
# Usage: update.sh [--yes]
#   --yes  — skip confirmation prompts (assume yes)
set -euo pipefail

YES_MODE=false
[[ "${1:-}" == "--yes" ]] && YES_MODE=true

# ── Paths ──────────────────────────────────────────────────────────────────

ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
SKILLS_SRC="$ROOT/skills"
TARGET="${CLAUDE_SKILLS_DIR:-$HOME/.claude/skills}"

COMMON_ROOT="${COMMON_ROOT:-$HOME/projects/.common}"
META_MCP="$COMMON_ROOT/lib/projects-meta-mcp"
INTERNS_MCP="$COMMON_ROOT/lib/interns-mcp"

# ── Helpers ────────────────────────────────────────────────────────────────

info()  { echo -e "\033[1;34m[update]\033[0m $*"; }
ok()    { echo -e "\033[1;32m[ok]\033[0m $*"; }
warn()  { echo -e "\033[1;33m[warn]\033[0m $*"; }
fail()  { echo -e "\033[1;31m[fail]\033[0m $*" >&2; exit 1; }

confirm() {
    local msg="$1"
    if $YES_MODE; then return 0; fi
    read -rp "$msg [y/N] " ans
    [[ "$ans" =~ ^[Yy] ]]
}

# ── Collect before-versions ────────────────────────────────────────────────

declare -A BEFORE_VERSIONS=()
if [[ -d "$TARGET" ]]; then
    for skill_dir in "$TARGET"/*/; do
        name="$(basename "$skill_dir")"
        vf="$skill_dir/SKILL.md"
        if [[ -f "$vf" ]]; then
            ver="$(grep -oP '^version:\s*\K[0-9]+\.[0-9]+\.[0-9]+' "$vf" 2>/dev/null || echo '?')"
            BEFORE_VERSIONS["$name"]="$ver"
        fi
    done
fi

# ── Step 1: git pull ────────────────────────────────────────────────────────

info "Pulling claude-skills repo..."
cd "$ROOT"

if [[ -n "$(git status --porcelain)" ]]; then
    warn "Working tree has uncommitted changes. Stashing..."
    git stash push -m "update-sh-auto-stash" || fail "Cannot stash changes"
    STASHED=true
else
    STASHED=false
fi

git pull --ff-only || fail "git pull --ff-only failed (diverged or no upstream)"
ok "Repo updated."

if $STASHED; then
    info "Popping stashed changes..."
    git stash pop || warn "Could not pop stash — resolve manually"
fi

# ── Step 2: projects-meta-mcp ─────────────────────────────────────────────

if [[ -d "$META_MCP/.git" ]]; then
    info "Checking projects-meta-mcp..."
    cd "$META_MCP"
    PRE_SHA="$(git rev-parse HEAD)"
    git pull --ff-only 2>/dev/null || warn "projects-meta-mcp: pull failed or no upstream"
    POST_SHA="$(git rev-parse HEAD)"

    if [[ "$PRE_SHA" != "$POST_SHA" ]]; then
        info "Source changed, rebuilding projects-meta-mcp..."
        npm run build 2>/dev/null || npm install && npm run build
        ok "projects-meta-mcp rebuilt."
        MCP_REBUILT=true
    else
        ok "projects-meta-mcp: up to date."
        MCP_REBUILT=false
    fi
else
    warn "projects-meta-mcp not found at $META_MCP — skipping."
    MCP_REBUILT=false
fi

# ── Step 3: interns-mcp ───────────────────────────────────────────────────

if [[ -d "$INTERNS_MCP/.git" ]]; then
    info "Checking interns-mcp..."
    cd "$INTERNS_MCP"
    PRE_SHA="$(git rev-parse HEAD)"
    git pull --ff-only 2>/dev/null || warn "interns-mcp: pull failed or no upstream"
    POST_SHA="$(git rev-parse HEAD)"

    if [[ "$PRE_SHA" != "$POST_SHA" ]]; then
        info "Source changed, reinstalling interns-mcp..."
        pip install -e . 2>/dev/null || pip3 install -e .
        ok "interns-mcp reinstalled."
        MCP_REBUILT=true
    else
        ok "interns-mcp: up to date."
    fi
else
    warn "interns-mcp not found at $INTERNS_MCP — skipping."
fi

# ── Step 4: Install skills ─────────────────────────────────────────────────

cd "$ROOT"
info "Installing skills..."
bash "$ROOT/scripts/install.sh"
ok "Skills installed."

# ── Step 5: Version diff ───────────────────────────────────────────────────

info "Version diff:"
CHANGES=false
for skill_dir in "$TARGET"/*/; do
    name="$(basename "$skill_dir")"
    vf="$skill_dir/SKILL.md"
    if [[ -f "$vf" ]]; then
        after="$(grep -oP '^version:\s*\K[0-9]+\.[0-9]+\.[0-9]+' "$vf" 2>/dev/null || echo '?')"
        before="${BEFORE_VERSIONS[$name]:-new}"
        if [[ "$before" != "$after" ]]; then
            echo "  $before → $after  ($name)"
            CHANGES=true
        fi
    fi
done
if ! $CHANGES; then
    echo "  (no version changes)"
fi

# ── Step 6: New setup-skills hint ──────────────────────────────────────────

NEW_SETUP=()
for skill_dir in "$SKILLS_SRC"/*/; do
    name="$(basename "$skill_dir")"
    if [[ "$name" == setup-* ]] && [[ ! -d "$TARGET/$name" ]]; then
        NEW_SETUP+=("$name")
    fi
done

if [[ ${#NEW_SETUP[@]} -gt 0 ]]; then
    echo ""
    info "New setup skills available:"
    for s in "${NEW_SETUP[@]}"; do
        echo "  - $s"
    done
    echo "  Run the setup skill to configure it."
fi

# ── Step 7: Reload hints ──────────────────────────────────────────────────

echo ""
ok "Update complete!"
if $MCP_REBUILT; then
    echo "  → Run /reload-mcp to reload MCP servers (source changed)"
fi
echo "  → Start a new Claude session for skill changes to take full effect"