#!/usr/bin/env bash
# tools/lsp/build.sh — Build the El LSP server binary end-to-end.
#
# Pipeline:
#   1. Compile el-lsp.el → C source (using elc)
#   2. Compile C source → binary (using cc with el_runtime.c)
#
# Output: tools/lsp/dist/el-lsp
#
# Prerequisites:
#   - dist/platform/elc  (the El self-hosted compiler)
#   - el-compiler/runtime/el_runtime.c + el_runtime.h
#   - cc (clang or gcc), libcurl, pthreads
#
# Usage:
#   cd <el-root>
#   ./tools/lsp/build.sh
#
#   Or from anywhere:
#   EL_HOME=/path/to/el-root ./tools/lsp/build.sh

set -euo pipefail

# ── Locate el root ─────────────────────────────────────────────────────────
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
EL_HOME="${EL_HOME:-$(cd "${SCRIPT_DIR}/../.." && pwd)}"

ELC="${ELC:-${EL_HOME}/dist/platform/elc}"
RUNTIME_DIR="${EL_HOME}/el-compiler/runtime"
LSP_DIR="${SCRIPT_DIR}"
OUT_DIR="${LSP_DIR}/dist"

# ── Validate prerequisites ─────────────────────────────────────────────────
echo "==> Checking prerequisites..."
echo "    EL_HOME    = ${EL_HOME}"
echo "    elc        = ${ELC}"
echo "    runtime    = ${RUNTIME_DIR}"

if [ ! -x "${ELC}" ]; then
    echo "error: elc not found at ${ELC}" >&2
    echo "       Build it first: cd <el-root> && make  (or compile elc-bootstrap.c)" >&2
    exit 1
fi

if [ ! -f "${RUNTIME_DIR}/el_runtime.c" ]; then
    echo "error: el_runtime.c not found at ${RUNTIME_DIR}" >&2
    exit 1
fi

if [ ! -f "${LSP_DIR}/el-lsp.el" ]; then
    echo "error: el-lsp.el not found at ${LSP_DIR}" >&2
    exit 1
fi

mkdir -p "${OUT_DIR}"

# ── Compile El → C ─────────────────────────────────────────────────────────
C_OUT="${OUT_DIR}/el-lsp.c"
echo "==> Compiling El → C..."
echo "    ${LSP_DIR}/el-lsp.el  →  ${C_OUT}"

# el-lsp.el uses only standard El builtins (no import statements needed).
# The elc compiler emits #include "el_runtime.h" at the top of the output.
"${ELC}" "${LSP_DIR}/el-lsp.el" > "${C_OUT}"

echo "    Done ($(wc -l < "${C_OUT}") lines of C)."

# ── Compile C → binary ─────────────────────────────────────────────────────
BIN="${OUT_DIR}/el-lsp"
echo "==> Compiling C → binary..."
echo "    ${C_OUT} + el_runtime.c  →  ${BIN}"

cc -std=c11 -O2 \
    -I "${RUNTIME_DIR}" \
    -o "${BIN}" \
    "${C_OUT}" "${RUNTIME_DIR}/el_runtime.c" \
    -lcurl -lpthread

echo "    Done."

# ── Summary ────────────────────────────────────────────────────────────────
echo
echo "==> Build complete."
echo
echo "    Binary : ${BIN}"
echo "    Size   : $(du -sh "${BIN}" | cut -f1)"
echo
echo "    Install system-wide:"
echo "      sudo cp ${BIN} /usr/local/bin/el-lsp"
echo
echo "    Quick smoke test (initialize + shutdown):"
cat << 'SMOKETEST'
      python3 - << 'PY'
import subprocess, json

def frame(body):
    b = body.encode()
    return f"Content-Length: {len(b)}\r\n\r\n".encode() + b

def send(proc, obj):
    proc.stdin.write(frame(json.dumps(obj)))
    proc.stdin.flush()

def recv(proc):
    hdr = b""
    while not hdr.endswith(b"\r\n\r\n"):
        hdr += proc.stdout.read(1)
    cl = int([l for l in hdr.decode().split("\r\n") if l.startswith("Content-Length")][0].split(": ")[1])
    return json.loads(proc.stdout.read(cl))

import sys, os
bin_path = sys.argv[1] if len(sys.argv) > 1 else "./dist/el-lsp"
proc = subprocess.Popen([bin_path], stdin=subprocess.PIPE, stdout=subprocess.PIPE)
send(proc, {"jsonrpc":"2.0","id":1,"method":"initialize","params":{"capabilities":{}}})
r = recv(proc)
print("initialize:", r.get("result", {}).get("serverInfo", {}).get("name"), "OK" if "result" in r else "FAIL")
send(proc, {"jsonrpc":"2.0","id":2,"method":"shutdown","params":{}})
r = recv(proc)
print("shutdown:", "OK" if r.get("result") is None else "FAIL")
send(proc, {"jsonrpc":"2.0","method":"exit","params":{}})
proc.wait()
print("exit: OK")
PY
SMOKETEST