#!/bin/bash
#
# SPDX-License-Identifier: GPL-2.0
#
# Copyright (c) 2026 AMLOGIC
#
# Environment configuration functions for AMLbian
#
# host_env_check.sh
#
# Check whether the current host environment is ready for building.
#

set -u

ERRORS=0

error() {
    echo "[ERROR] $1" >&2
    ERRORS=$((ERRORS + 1))
}

warn() {
    echo "[WARN] $1" >&2
}

info() {
    echo "[INFO] $1"
}

check_toolchain_dir() {
    local dir="$1"
    local name="$2"

    if [[ -d "$dir" ]]; then
        info "Toolchain '$name' found at $dir"
    else
        error "Required toolchain '$name' is missing: $dir"
        warn "Please install '$name' toolchain before starting the build."
    fi
}

check_arm_gnu_linux_toolchain() {
    local exact_dir="/opt/arm-gnu-toolchain-11.3.rel1-x86_64-aarch64-none-linux-gnu"
    local min_version="11.3.rel1"
    local pattern="/opt/arm-gnu-toolchain-*-x86_64-aarch64-none-linux-gnu"

    if [[ -d "$exact_dir" ]]; then
        info "Toolchain 'arm-gnu-toolchain-11.3.rel1 aarch64-none-linux-gnu' found at $exact_dir"
        return
    fi

    local found=0
    local found_dir=""
    local found_version=""

    for dir in $pattern; do
        # If no matches, the literal pattern is returned; skip it.
        [[ -d "$dir" ]] || continue

        local version
        version=$(echo "$dir" | sed -E 's|.*/arm-gnu-toolchain-([^/-]+)-x86_64-aarch64-none-linux-gnu|\1|')

        if version_ge "$version" "$min_version"; then
            found=1
            found_dir="$dir"
            found_version="$version"
            break
        fi
    done

    if [[ "$found" -eq 1 ]]; then
        info "Compatible aarch64-none-linux-gnu toolchain found at $found_dir (version $found_version, >= $min_version)"
        warn "Please confirm this toolchain version is suitable before starting the build."
    else
        error "Required toolchain 'arm-gnu-toolchain-11.3.rel1 aarch64-none-linux-gnu' is missing"
        warn "Please install 'arm-gnu-toolchain-11.3.rel1-x86_64-aarch64-none-linux-gnu' or a newer compatible version."
    fi
}

check_arch_test_arm64() {
    if ! command -v arch-test >/dev/null 2>&1; then
        error "arch-test is not installed or not in PATH"
        warn "Please install arch-test and ensure arm64 support is available."
        return
    fi

    if arch-test arm64 >/dev/null 2>&1; then
        info "arch-test reports arm64 support is available"
    else
        error "arch-test does NOT report arm64 support"
        warn "Please prepare arm64 execution support (e.g. binfmt/qemu-user) before starting the build."
    fi
}

# Compare two dotted version strings.
# Returns 0 if $1 >= $2, 1 otherwise.
version_ge() {
    local v1="$1"
    local v2="$2"

    # Normalize to three numeric fields, discarding any trailing non-numeric suffix.
    local a1 a2 a3
    local b1 b2 b3

    a1=$(echo "$v1" | sed -n -E 's/^([0-9]+).*/\1/p')
    a2=$(echo "$v1" | sed -n -E 's/^[0-9]+\.([0-9]+).*/\1/p')
    a3=$(echo "$v1" | sed -n -E 's/^[0-9]+\.[0-9]+\.([0-9]+).*/\1/p')

    b1=$(echo "$v2" | sed -n -E 's/^([0-9]+).*/\1/p')
    b2=$(echo "$v2" | sed -n -E 's/^[0-9]+\.([0-9]+).*/\1/p')
    b3=$(echo "$v2" | sed -n -E 's/^[0-9]+\.[0-9]+\.([0-9]+).*/\1/p')

    # Treat missing fields as 0.
    a1=${a1:-0}; a2=${a2:-0}; a3=${a3:-0}
    b1=${b1:-0}; b2=${b2:-0}; b3=${b3:-0}

    if [[ "$a1" -gt "$b1" ]]; then return 0; fi
    if [[ "$a1" -lt "$b1" ]]; then return 1; fi
    if [[ "$a2" -gt "$b2" ]]; then return 0; fi
    if [[ "$a2" -lt "$b2" ]]; then return 1; fi
    if [[ "$a3" -ge "$b3" ]]; then return 0; fi
    return 1
}

check_qemu_aarch64() {
    local cmd="qemu-aarch64-static"
    local min_version="6.2.0"

    if ! command -v "$cmd" >/dev/null 2>&1; then
        error "$cmd is not installed or not in PATH"
        warn "Please install QEMU user-mode static for aarch64 (>= $min_version) before starting the build."
        return
    fi

    local version_line
    version_line=$($cmd --version 2>&1 | head -n1)

    local version
    version=$(echo "$version_line" | sed -E 's/.*version[[:space:]]+([0-9]+(\.[0-9]+)*).*/\1/')

    if [[ -z "$version" ]]; then
        error "Could not determine $cmd version from: $version_line"
        warn "Please ensure $cmd is working and >= $min_version."
        return
    fi

    if version_ge "$version" "$min_version"; then
        info "$cmd version $version is OK (>= $min_version)"
    else
        error "$cmd version $version is too old (minimum required: $min_version)"
        warn "Please upgrade $cmd to >= $min_version before starting the build."
    fi
}

main() {
    echo "========================================"
    echo "Host environment check"
    echo "========================================"

    check_toolchain_dir "/opt/gcc-linaro-7.3.1-2018.05-i686_aarch64-elf" "gcc-linaro-7.3.1 aarch64-elf"
    check_toolchain_dir "/opt/riscv-none-gcc" "riscv-none-gcc"
    check_toolchain_dir "/opt/arm-gnu-toolchain-13.2.Rel1-x86_64-aarch64-none-elf" "arm-gnu-toolchain-13.2.Rel1 aarch64-none-elf"

    check_arm_gnu_linux_toolchain

    check_arch_test_arm64

    check_qemu_aarch64

    echo "========================================"
    if [[ "$ERRORS" -eq 0 ]]; then
        echo "Result: PASS - Host environment looks ready."
        return 0
    else
        echo "Result: FAIL - $ERRORS issue(s) found. Please fix them before starting the build."
        warn "Please read the Release Notes carefully or contact FAE for technical support."
        return 1
    fi
}

main "$@"