#!/usr/bin/env bash
# new-project.sh — scaffold a new El project.
#
# Usage:
#   ./tools/new-project.sh <project-name>
#
# Creates:
#   <project-name>/
#     src/main.el      — hello world entry point
#     build.sh         — build script using elc + el_runtime.c
#     README.md        — minimal project docs

set -euo pipefail

if [[ $# -lt 1 ]]; then
    echo "Usage: $0 <project-name>" >&2
    exit 1
fi

NAME="$1"

if [[ -e "${NAME}" ]]; then
    echo "Error: '${NAME}' already exists." >&2
    exit 1
fi

# Discover elc — prefer PATH, fall back to the local foundation/el tree
ELC="elc"
if ! command -v elc >/dev/null 2>&1; then
    # Try a sibling or parent path convention
    SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
    LOCAL_ELC="${SCRIPT_DIR}/../dist/platform/elc"
    if [[ -x "${LOCAL_ELC}" ]]; then
        ELC="$(cd "$(dirname "${LOCAL_ELC}")" && pwd)/$(basename "${LOCAL_ELC}")"
    else
        echo "Warning: elc not found in PATH or at ${LOCAL_ELC}" >&2
        echo "         The generated build.sh may need manual adjustment." >&2
        ELC="elc"
    fi
fi

# Discover el_runtime.c
EL_RUNTIME=""
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
LOCAL_RUNTIME="${SCRIPT_DIR}/../el-compiler/runtime/el_runtime.c"
if [[ -f "${LOCAL_RUNTIME}" ]]; then
    EL_RUNTIME="$(cd "$(dirname "${LOCAL_RUNTIME}")" && pwd)/$(basename "${LOCAL_RUNTIME}")"
    EL_INCLUDE="$(dirname "${EL_RUNTIME}")"
else
    # Check installed location
    if [[ -f "/usr/local/el/lib/libel.a" ]]; then
        EL_RUNTIME_LINK="-L/usr/local/el/lib -lel"
        EL_INCLUDE="/usr/local/el/include"
    fi
    EL_RUNTIME="${EL_RUNTIME_LINK:-}"
fi

echo "==> Scaffolding El project: ${NAME}"

mkdir -p "${NAME}/src" "${NAME}/dist"

# src/main.el
cat > "${NAME}/src/main.el" <<'ELEOF'
// main.el — entry point for this El program.

fn run() -> String {
    println("hello from El!")
    return ""
}

run()
ELEOF

# build.sh — adapts to whether we found elc/runtime locally or installed
if [[ -n "${EL_RUNTIME}" && -f "${EL_RUNTIME}" ]]; then
    # Local source tree runtime
    EL_INCLUDE_DIR="$(dirname "${EL_RUNTIME}")"
    cat > "${NAME}/build.sh" <<BUILDEOF
#!/usr/bin/env bash
# build.sh — build ${NAME}
set -euo pipefail

ELC="${ELC}"
EL_RUNTIME="${EL_RUNTIME}"
EL_INCLUDE="${EL_INCLUDE_DIR}"

mkdir -p dist

echo "==> Compiling El -> C"
"\${ELC}" src/main.el > dist/main.c

echo "==> Compiling C -> binary"
cc -std=c11 -O2 -I"\${EL_INCLUDE}" -o dist/${NAME} dist/main.c "\${EL_RUNTIME}" -lcurl -lpthread

echo "==> Built: dist/${NAME}"
BUILDEOF
else
    # Installed framework
    cat > "${NAME}/build.sh" <<BUILDEOF
#!/usr/bin/env bash
# build.sh — build ${NAME}
# Requires El installed via tools/install.sh (elc in PATH, /usr/local/el/lib/libel.a)
set -euo pipefail

ELC="\${ELC:-elc}"
EL_PREFIX="\${EL_HOME:-/usr/local/el}"

mkdir -p dist

echo "==> Compiling El -> C"
"\${ELC}" src/main.el > dist/main.c

echo "==> Compiling C -> binary"
cc -std=c11 -O2 -I"\${EL_PREFIX}/include" -o dist/${NAME} dist/main.c -L"\${EL_PREFIX}/lib" -lel -lcurl -lpthread

echo "==> Built: dist/${NAME}"
BUILDEOF
fi

chmod +x "${NAME}/build.sh"

# README.md
cat > "${NAME}/README.md" <<READMEEOF
# ${NAME}

An El language project.

## Build

\`\`\`bash
./build.sh
\`\`\`

## Run

\`\`\`bash
./dist/${NAME}
\`\`\`

## Structure

\`\`\`
src/main.el      — entry point
build.sh         — build script
dist/            — compiled output (gitignored)
\`\`\`
READMEEOF

# .gitignore
cat > "${NAME}/.gitignore" <<'IGNEOF'
dist/
*.c
IGNEOF

echo
echo "==> Created ${NAME}/"
echo "    src/main.el"
echo "    build.sh"
echo "    README.md"
echo "    .gitignore"
echo
echo "To build:"
echo "    cd ${NAME} && ./build.sh"
echo