#!/bin/sh
set -e

REPO="one-bit/oc-mnemoria"
COMMANDS_DIR="commands"
CONFIG_FILE="opencode.json"
PROJECT_DIR="$(pwd)"
OPENCODE_DIR="$PROJECT_DIR/.opencode"
PACKAGE_FILE="$OPENCODE_DIR/package.json"
PLUGIN_FILE="$OPENCODE_DIR/plugins/oc-mnemoria.js"  # legacy; cleaned up below

echo "=========================================="
echo "  oc-mnemoria Installer"
echo "=========================================="
echo ""

# ── Step 0: Check prerequisites ──────────────────────────────────────────────

echo "0. Checking prerequisites..."

MNEMORIA_VERSION="0.3.5"

# Compare two semver strings. Returns 0 if $1 >= $2, 1 otherwise.
version_gte() {
    # Split on dots and compare numerically
    IFS='.' read -r a1 a2 a3 <<EOF
$1
EOF
    IFS='.' read -r b1 b2 b3 <<EOF
$2
EOF
    a1=${a1:-0}; a2=${a2:-0}; a3=${a3:-0}
    b1=${b1:-0}; b2=${b2:-0}; b3=${b3:-0}
    [ "$a1" -gt "$b1" ] && return 0
    [ "$a1" -lt "$b1" ] && return 1
    [ "$a2" -gt "$b2" ] && return 0
    [ "$a2" -lt "$b2" ] && return 1
    [ "$a3" -ge "$b3" ] && return 0
    return 1
}

if ! command -v mnemoria >/dev/null 2>&1; then
    echo "   'mnemoria' CLI not found."
    if command -v cargo >/dev/null 2>&1; then
        echo "   Installing mnemoria v$MNEMORIA_VERSION via cargo..."
        cargo install "mnemoria@$MNEMORIA_VERSION"
    else
        echo "   ERROR: Neither 'mnemoria' nor 'cargo' found."
        echo "   Install Rust first: https://rustup.rs"
        echo "   Then run: cargo install mnemoria@$MNEMORIA_VERSION"
        exit 1
    fi
else
    CURRENT_VERSION="$(mnemoria --version 2>/dev/null | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' || echo "0.0.0")"
    echo "   mnemoria CLI found: $(command -v mnemoria) (v$CURRENT_VERSION)"
    if ! version_gte "$CURRENT_VERSION" "$MNEMORIA_VERSION"; then
        echo "   Version $CURRENT_VERSION is below required $MNEMORIA_VERSION. Updating..."
        if command -v cargo >/dev/null 2>&1; then
            cargo install "mnemoria@$MNEMORIA_VERSION"
        else
            echo "   WARNING: cargo not found. Please update mnemoria manually:"
            echo "   cargo install mnemoria@$MNEMORIA_VERSION"
        fi
    fi
fi
echo ""

# ── Step 1: Configure plugin ─────────────────────────────────────────────────

ensure_project_config() {
    if [ ! -f "$PROJECT_DIR/$CONFIG_FILE" ]; then
        echo "   Creating $CONFIG_FILE with oc-mnemoria plugin..."
        cat > "$PROJECT_DIR/$CONFIG_FILE" <<'EOF'
{
  "$schema": "https://opencode.ai/config.json",
  "plugin": ["oc-mnemoria"]
}
EOF
        echo "   Created $PROJECT_DIR/$CONFIG_FILE"
        return
    fi

    if command -v jq >/dev/null 2>&1; then
        # Remove any legacy entries and add the canonical "oc-mnemoria" entry
        jq '
          .plugin = (
            [(.plugin // [])[] | select(. != "oc-mnemoria" and . != "oc-mnemoria/plugin" and . != "@oc-mnemoria/plugin")]
            + ["oc-mnemoria"]
          )
        ' "$PROJECT_DIR/$CONFIG_FILE" > "$PROJECT_DIR/$CONFIG_FILE.tmp" && mv "$PROJECT_DIR/$CONFIG_FILE.tmp" "$PROJECT_DIR/$CONFIG_FILE"
        echo "   Added oc-mnemoria to plugin array in $CONFIG_FILE"
    elif grep -q '"oc-mnemoria"' "$PROJECT_DIR/$CONFIG_FILE" 2>/dev/null; then
        echo "   Found oc-mnemoria in $CONFIG_FILE"
    else
        echo "   Warning: jq not found. Please add \"oc-mnemoria\" to the plugin array in $CONFIG_FILE."
    fi
}

cleanup_legacy_wrapper() {
    if [ -f "$PLUGIN_FILE" ]; then
        rm -f "$PLUGIN_FILE"
        echo "   Removed legacy wrapper plugin $PLUGIN_FILE"
    fi
}

echo "1. Configuring plugin..."
ensure_project_config
cleanup_legacy_wrapper
echo ""

# ── Step 2: Install commands ─────────────────────────────────────────────────

install_commands() {
    cwd="$(pwd)"
    script_dir="$(cd "$(dirname "$0")" 2>/dev/null && pwd)"
    commands_source=""

    if [ -d "$cwd/$COMMANDS_DIR" ]; then
        commands_source="$cwd/$COMMANDS_DIR"
    elif [ -d "$script_dir/$COMMANDS_DIR" ]; then
        commands_source="$script_dir/$COMMANDS_DIR"
    elif [ -d "$script_dir/../commands" ]; then
        commands_source="$script_dir/../commands"
    fi

    if [ -z "$commands_source" ]; then
        echo "   Downloading commands from GitHub..."
        temp_dir="$(mktemp -d)"
        curl -sSL "https://github.com/$REPO/archive/refs/heads/main.tar.gz" | tar -xz -C "$temp_dir"
        commands_source="$temp_dir/oc-mnemoria-main/commands"
    fi

    target_dir="$OPENCODE_DIR/commands"
    mkdir -p "$target_dir"

    if [ -d "$commands_source" ]; then
        cp -f "$commands_source"/mn-*.md "$target_dir/" 2>/dev/null || true
        echo "   Installed mn-* commands to $target_dir"
    else
        echo "   Warning: Could not find commands to install"
    fi
}

echo "2. Installing commands..."
install_commands
echo ""

# ── Done ─────────────────────────────────────────────────────────────────────

echo "=========================================="
echo "  Installation complete!"
echo "=========================================="
echo ""
echo "Configured:"
echo "  - $PROJECT_DIR/$CONFIG_FILE (plugin entry)"
echo "  - $OPENCODE_DIR/commands/ (mn-* slash commands)"
echo ""
echo "Next steps:"
echo "  1. Restart OpenCode"
echo "  2. Run /mn-stats to verify"
echo ""
echo "Shared memory store will be created at:"
echo "  .opencode/mnemoria/"
echo ""