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

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
cd "$SCRIPT_DIR"

# --- Colors ---
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
CYAN='\033[0;36m'
BOLD='\033[1m'
DIM='\033[2m'
NC='\033[0m'

# --- Config ---
KEYSTORE_DIR="keystore"
KEYSTORE_FILE="$KEYSTORE_DIR/radio247-release.jks"
KEY_ALIAS="radio247"
DIST_DIR="dist"
GRADLE_BUILD_FILE="app/build.gradle.kts"

banner() {
    echo ""
    echo -e "${CYAN}╔══════════════════════════════════╗${NC}"
    echo -e "${CYAN}║${BOLD}     Radio 247 Build Tool         ${NC}${CYAN}║${NC}"
    echo -e "${CYAN}╚══════════════════════════════════╝${NC}"
    echo ""
}

info()    { echo -e "${BLUE}▸${NC} $1"; }
success() { echo -e "${GREEN}✓${NC} $1"; }
warn()    { echo -e "${YELLOW}⚠${NC} $1"; }
error()   { echo -e "${RED}✗${NC} $1"; }

get_version_name() {
    if [[ ! -f "$GRADLE_BUILD_FILE" ]]; then
        error "Build file not found: $GRADLE_BUILD_FILE"
        exit 1
    fi
    local v
    v=$(grep 'versionName' "$GRADLE_BUILD_FILE" | head -1 | sed 's/.*"\([^"]*\)".*/\1/')
    if [[ -z "$v" ]]; then
        error "Could not extract version from $GRADLE_BUILD_FILE"
        exit 1
    fi
    echo "$v"
}

preflight_check() {
    local ok=true

    if ! command -v java &>/dev/null && [[ -z "${JAVA_HOME:-}" ]]; then
        error "Java not found. Install JDK 17+ or set JAVA_HOME."
        ok=false
    fi

    if ! command -v keytool &>/dev/null; then
        error "keytool not found. It ships with the JDK — check your JAVA_HOME/PATH."
        ok=false
    fi

    if [[ ! -x "./gradlew" ]]; then
        error "Gradle wrapper not found or not executable."
        ok=false
    fi

    if [[ "$ok" != true ]]; then
        exit 1
    fi
}

ensure_dist_dir() {
    mkdir -p "$DIST_DIR"
}

main_menu() {
    echo -e "${BOLD}What would you like to do?${NC}"
    echo ""
    echo -e "  ${BOLD}1)${NC} Build Release APK  ${DIM}(signed, shareable)${NC}"
    echo -e "  ${BOLD}2)${NC} Build Debug APK    ${DIM}(quick, for testing)${NC}"
    echo -e "  ${BOLD}3)${NC} Manage Keystore    ${DIM}(create or check signing key)${NC}"
    echo -e "  ${BOLD}4)${NC} Clean              ${DIM}(remove build artifacts)${NC}"
    echo -e "  ${BOLD}5)${NC} Exit"
    echo ""

    local choice
    read -rp "> " choice
    case $choice in
        1) build_release ;;
        2) build_debug ;;
        3) manage_keystore ;;
        4) clean_build ;;
        5) echo ""; exit 0 ;;
        *) warn "Invalid choice. Pick 1-5." ;;
    esac
}

read_keystore_password() {
    local password
    read -rsp "Keystore password: " password
    echo >&2
    echo "$password"
}

create_keystore() {
    echo -e "${BOLD}No keystore found. Let's create one.${NC}"
    echo ""

    local cn org password password_confirm

    read -rp "Your name (for the certificate): " cn
    [[ -z "$cn" ]] && { error "Name is required."; return 1; }

    read -rp "Organization (optional, Enter to skip): " org

    while true; do
        read -rsp "Password (min 6 chars): " password
        echo
        if [[ ${#password} -lt 6 ]]; then
            warn "Password must be at least 6 characters."
            continue
        fi
        read -rsp "Confirm password: " password_confirm
        echo
        if [[ "$password" != "$password_confirm" ]]; then
            warn "Passwords don't match. Try again."
            continue
        fi
        break
    done

    mkdir -p "$KEYSTORE_DIR"

    local dname="CN=$cn"
    [[ -n "$org" ]] && dname="$dname, O=$org"

    info "Creating keystore..."

    local keytool_err
    keytool_err=$(mktemp)

    keytool -genkeypair \
        -alias "$KEY_ALIAS" \
        -keyalg RSA \
        -keysize 2048 \
        -validity 10000 \
        -keystore "$KEYSTORE_FILE" \
        -storepass "$password" \
        -keypass "$password" \
        -dname "$dname" \
        2>"$keytool_err" || true

    if [[ -f "$KEYSTORE_FILE" ]]; then
        rm -f "$keytool_err"
        echo ""
        success "Keystore created at ${BOLD}$KEYSTORE_FILE${NC}"
        echo ""
        warn "IMPORTANT: Back up this file and remember your password."
        warn "If you lose either, you cannot update the app on devices"
        warn "that already have this version installed."
    else
        error "Keystore creation failed."
        if [[ -s "$keytool_err" ]]; then
            echo -e "${DIM}$(cat "$keytool_err")${NC}" >&2
        fi
        rm -f "$keytool_err"
        return 1
    fi
}

manage_keystore() {
    if [[ -f "$KEYSTORE_FILE" ]]; then
        success "Keystore exists at ${BOLD}$KEYSTORE_FILE${NC}"
        echo ""
        info "Keystore details:"
        keytool -list -keystore "$KEYSTORE_FILE" -alias "$KEY_ALIAS" \
            -storepass "$(read_keystore_password)" 2>/dev/null \
            || warn "Could not read keystore (wrong password?)"
        return
    fi

    create_keystore
}

copy_apk() {
    local build_type="$1"
    local version
    version="$(get_version_name)"

    local source_apk="app/build/outputs/apk/$build_type/app-$build_type.apk"

    if [[ ! -f "$source_apk" ]]; then
        error "APK not found at $source_apk"
        return 1
    fi

    ensure_dist_dir

    local dest_name="radio247-v${version}-${build_type}.apk"
    local dest_path="$DIST_DIR/$dest_name"

    cp "$source_apk" "$dest_path"

    local size
    size="$(du -h "$dest_path" | cut -f1 | xargs)"

    echo ""
    success "Build complete!"
    echo ""
    echo -e "  ${BOLD}APK:${NC}  $dest_path"
    echo -e "  ${BOLD}Size:${NC} $size"
    echo ""
    echo -e "  ${DIM}Share this file with anyone — they can install it${NC}"
    echo -e "  ${DIM}on Android 9+ by opening the APK on their device.${NC}"
}

build_release() {
    info "Preparing release build..."
    echo ""

    if [[ ! -f "$KEYSTORE_FILE" ]]; then
        warn "No keystore found. You need one to sign a release APK."
        echo ""
        local yn
        read -rp "Create one now? (y/n) " yn
        case $yn in
            [Yy]*) create_keystore || return 1 ;;
            *)     return 0 ;;
        esac
        echo ""
    fi

    local password
    read -rsp "Keystore password: " password
    echo ""
    echo ""

    info "Building release APK... (this may take a minute)"
    echo ""

    local store_file
    store_file="$(cd "$(dirname "$KEYSTORE_FILE")" && pwd)/$(basename "$KEYSTORE_FILE")"

    if ./gradlew assembleRelease \
        -Pandroid.injected.signing.store.file="$store_file" \
        -Pandroid.injected.signing.store.password="$password" \
        -Pandroid.injected.signing.key.alias="$KEY_ALIAS" \
        -Pandroid.injected.signing.key.password="$password"; then

        copy_apk "release"
    else
        echo ""
        error "Build failed. Check the output above for details."
        return 1
    fi
}

build_debug() {
    info "Building debug APK..."
    echo ""

    if ./gradlew assembleDebug; then
        copy_apk "debug"
    else
        echo ""
        error "Build failed. Check the output above for details."
        return 1
    fi
}

clean_build() {
    info "Cleaning build artifacts..."

    ./gradlew clean 2>/dev/null

    if [[ -d "$DIST_DIR" ]]; then
        rm -rf "$DIST_DIR"
        success "Removed $DIST_DIR/"
    fi

    success "Clean complete."
}

# --- Main ---
preflight_check
banner
while true; do
    main_menu
    echo ""
done