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

# Find the odin binary
export PATH="$HOME/.odin:$PATH"


SRC_DIR="src"
OUT_DIR="out"
OUT_NAME="pong"

# flags for every odin build; unix-style errors (file:line:col: msg) are what the vis error picker parses
ODIN_FLAGS=(-error-pos-style:unix)

# ---- ctags ------------------------------------------------------------
# tags = project tags (-t, vis runs it on every .odin save)
# + stdlib tags (-T, once, or after an Odin update), shared by all projects
TAGS_FILE="tags"
STD_TAGS="${XDG_CACHE_HOME:-$HOME/.cache}/odin-tags/std.tags"

# --languages=Odin keeps vendor's bundled C/JS out of the index;
# --fields=+n adds the line:N field the vis pickers jump to
CTAGS_OPTS=(--languages=Odin --fields=+n)
# -----------------------------------------------------------------------

BUILD_ONLY=0
OPTIMIZED=0
WEB=0
CLEAN=0
DEBUGGER=0
VALGRIND=0
TAGS=""

usage() {
    echo "Usage: $0 [-b] [-o] [-w] [-d] [-v] [-c] [-t] [-T] [-h]"
    echo "  -b    build only, don't run"
    echo "  -o    optimized release build (-o:speed, no debug info)"
    echo "  -w    web/WASM build (js_wasm32 target)"
    echo "  -d    build then launch in debugger instead of running"
    echo "  -v    build then run under Valgrind"
    echo "  -c    clean build artifacts"
    echo "  -t    re-index $SRC_DIR and merge it with the stdlib tags"
    echo "  -T    index Odin core + vendor (once, or after an Odin update)"
    echo "  -h    show this help"
    exit 1
}

# stdlib tags, header lines stripped so the merged file keeps only one set
generate_std_tags() {
    local root
    root="$(odin root 2>/dev/null || echo "$HOME/.odin")"
    root="${root%/}"

    mkdir -p "$(dirname "$STD_TAGS")"
    ctags -R -f - "${CTAGS_OPTS[@]}" "$root/core" "$root/vendor" | grep -v '^!_TAG_' > "$STD_TAGS.tmp"
    mv -f "$STD_TAGS.tmp" "$STD_TAGS"
    echo "Stdlib tags written -> $STD_TAGS"
}

# project tags merged with the stdlib tags; both inputs are byte-sorted
generate_tags() {
    if [ ! -f "$STD_TAGS" ]; then
        echo "No stdlib tags; run $0 -T first" >&2
        exit 1
    fi

    # $$ keeps two overlapping on-save runs from sharing temp files
    local src_tags="$TAGS_FILE.src.$$"
    local merged="$TAGS_FILE.tmp.$$"

    ctags -R -f "$src_tags" "${CTAGS_OPTS[@]}" "$SRC_DIR"
    LC_ALL=C sort -m -u "$src_tags" "$STD_TAGS" > "$merged"
    mv -f "$merged" "$TAGS_FILE"
    rm -f "$src_tags"
}

while getopts "bowdvctTh" opt; do
    case $opt in
        b) BUILD_ONLY=1 ;;
        o) OPTIMIZED=1 ;;
        w) WEB=1 ;;
        d) DEBUGGER=1 ;;
        v) VALGRIND=1 ;;
        c) CLEAN=1 ;;
        t) TAGS=src ;;
        T) TAGS=std ;;
        h) usage ;;
        *) usage ;;
    esac
done

case "$TAGS" in
    src) generate_tags; exit 0 ;;
    std) generate_std_tags; exit 0 ;;
esac

mkdir -p "$OUT_DIR"

if [ "$CLEAN" -eq 1 ]; then
    echo "Cleaning..."
    rm -rf "${OUT_DIR:?}"/*
    exit 0
fi

if [ "$WEB" -eq 1 ]; then
    echo "Building web (WASM)..."
    odin build "$SRC_DIR" "${ODIN_FLAGS[@]}" \
        -target:js_wasm32 \
        -out:"$OUT_DIR/$OUT_NAME.wasm" \
        $( [ "$OPTIMIZED" -eq 1 ] && echo "-o:speed" || echo "-debug" )

    # Copy the HTML shell if one exists
    if [ -f "web/index_template.html" ]; then
        cp web/index_template.html "$OUT_DIR/index.html"
    fi

    echo "Web build complete -> $OUT_DIR/$OUT_NAME.wasm"
    exit 0
fi

if [ "$OPTIMIZED" -eq 1 ]; then
    echo "Building optimized ($SRC_DIR -> $OUT_DIR/$OUT_NAME)..."
    odin build "$SRC_DIR" "${ODIN_FLAGS[@]}" \
        -out:"$OUT_DIR/$OUT_NAME" \
        -o:speed \
        -no-bounds-check
else
    echo "Building debug ($SRC_DIR -> $OUT_DIR/$OUT_NAME)..."
    odin build "$SRC_DIR" "${ODIN_FLAGS[@]}" \
        -out:"$OUT_DIR/$OUT_NAME" \
        -debug \
        -define:DEBUG_MODE=true
fi

echo "Build complete."

if [ "$BUILD_ONLY" -eq 0 ]; then
    echo "----------------------------------------"

    if [ "$DEBUGGER" -eq 1 ]; then
        lldb "$OUT_DIR/$OUT_NAME"

    elif [ "$VALGRIND" -eq 1 ]; then
        VG_STATUS=0
        valgrind \
        --leak-check=full \
        --show-leak-kinds=definite,possible \
        --track-origins=yes \
        --errors-for-leak-kinds=definite,possible \
        --error-exitcode=1 \
        --log-file="$OUT_DIR/valgrind.log" \
        "./$OUT_DIR/$OUT_NAME" || VG_STATUS=$?

        echo
        echo "Valgrind report written to $OUT_DIR/valgrind.log"
        [ "$VG_STATUS" -ne 0 ] && echo "Valgrind reported errors (exit $VG_STATUS)"
        exit "$VG_STATUS"
    else
        "./$OUT_DIR/$OUT_NAME"
    fi
fi