#!/usr/bin/env bash
#
# Builds the qol-tweaks plugin jar.
#
# The build pins a Java toolchain version in build.gradle.kts. This script
# finds that version on your machine, and if it isn't installed it transparently
# falls back to the highest JDK that is (so `./build.sh` just works).
#
# Usage: ./build.sh [extra gradle args...]
set -euo pipefail

cd "$(dirname "$0")"

# --- 1. which Java version does the build pin? --------------------------------
pinned="$(grep -oE 'JavaLanguageVersion\.of\([0-9]+\)' build.gradle.kts | grep -oE '[0-9]+' | head -1 || true)"
pinned="${pinned:-25}"

# --- 2. find an installed JDK for a given version ------------------------------
java_major() { # $1 = path to java binary; echoes its major version (e.g. 26)
    "$1" -version 2>&1 | grep -oE '"([0-9]+)' | head -1 | tr -d '"'
}

find_java_home() { # $1 = version (e.g. 25); echoes a home whose java matches, or fails
    local -a candidates=()
    if [[ -x /usr/libexec/java_home ]]; then
        local mac_home
        if mac_home="$(/usr/libexec/java_home -v "$1" 2>/dev/null)"; then
            candidates+=("$mac_home")
        fi
    fi
    [[ -n "${JAVA_HOME:-}" ]] && candidates+=("$JAVA_HOME")

    local home bin ver
    for home in "${candidates[@]}"; do
        bin="$home/bin/java"
        [[ -x "$bin" ]] || continue
        ver="$(java_major "$bin")"
        if [[ -n "$ver" && "$ver" == "$1" ]]; then
            echo "$home"
            return 0
        fi
    done
    return 1
}

# --- 3. pick the JDK to build with --------------------------------------------
selected=""
selected_home=""
for v in "$pinned" 26 25 24 23 22 21 20 17; do
    if h="$(find_java_home "$v")"; then
        selected="$v"
        selected_home="$h"
        break
    fi
done

if [[ -z "$selected" ]]; then
    echo "error: no JDK found. Install any JDK 17+ (e.g. Java 25) and try again." >&2
    exit 1
fi

export JAVA_HOME="$selected_home"
export PATH="$JAVA_HOME/bin:$PATH"

gradle_args=()
override_init=""

if [[ "$selected" != "$pinned" ]]; then
    echo "note: pinned JDK $pinned not found; building with installed JDK $selected."
    override_init="${TMPDIR:-/tmp}/qol-tweaks-toolchain-$pinned-$selected.gradle"
    cat > "$override_init" <<EOF
gradle.afterProject { p ->
    if (p.plugins.hasPlugin('java')) {
        p.extensions.findByName('java').toolchain.languageVersion.set(JavaLanguageVersion.of($selected))
        p.tasks.withType(JavaCompile).configureEach {
            options.release.set($pinned)
        }
    }
}
EOF
    gradle_args+=(-I "$override_init")
    # the init script is external input, so a cached configuration would be stale
    gradle_args+=(--no-configuration-cache)
fi

trap '[[ -n "$override_init" ]] && rm -f "$override_init"' EXIT

if [[ $# -eq 0 ]]; then
    gradle_args+=(build)
else
    gradle_args+=("$@")
fi

echo "Using JDK $selected at $JAVA_HOME"
./gradlew "${gradle_args[@]}"

jar="$(ls -1 build/libs/*.jar 2>/dev/null | grep -Ev '(-sources|-javadoc)\.jar$' | head -1 || true)"
if [[ -n "$jar" ]]; then
    echo
    echo "Done. Plugin jar: $(pwd)/$jar"
fi