AI Coding Pair Programmer: Explain, Debug, Convert, and Review Code

# AI Coding Pair Programmer — Streamlit + Groq
# Save as app.py, add GROQ_API_KEY to .streamlit/secrets.toml, then: streamlit run app.py

import ssl

import httpx
import streamlit as st
import truststore

MAX_CODE_CHARS = 8000

st.set_page_config(page_title="AI Coding Pair Programmer", layout="wide")
st.title("AI Coding Pair Programmer")
st.caption(
    "Paste your code or pseudocode and get step-by-step explanations, bug detection, "
    "fixes, or a fully converted working implementation."
)

_ssl_ctx = truststore.SSLContext(ssl.PROTOCOL_TLS_CLIENT)


@st.cache_resource
def _groq_client():
    import groq

    return groq.Groq(
        api_key=st.secrets["GROQ_API_KEY"],
        http_client=httpx.Client(verify=_ssl_ctx),
    )


_MODEL = "llama-3.3-70b-versatile"

LANGUAGES = [
    "Python", "JavaScript", "TypeScript", "Java", "C++", "C#", "Go",
    "Rust", "Ruby", "PHP", "Swift", "Kotlin", "SQL", "Bash", "Other",
]

# ── Input panel ────────────────────────────────────────────────────────────────
col_input, col_output = st.columns([1, 1], gap="large")

with col_input:
    st.subheader("Your Code")
    lang = st.selectbox("Language", LANGUAGES)
    code_input = st.text_area(
        "Paste code or pseudocode",
        height=350,
        placeholder="def fibonacci(n):\n    # TODO: implement\n    pass",
    )
    context = st.text_input(
        "Additional context (optional)",
        placeholder="e.g. This is part of a web scraper, focus on performance",
    )

    st.divider()
    col_b1, col_b2 = st.columns(2)
    do_explain = col_b1.button("Explain Code", type="primary", use_container_width=True)
    do_debug = col_b2.button("Find Bugs & Fix", use_container_width=True)
    col_b3, col_b4 = st.columns(2)
    do_convert = col_b3.button("Convert Pseudocode", use_container_width=True)
    do_review = col_b4.button("Code Review", use_container_width=True)

with col_output:
    st.subheader("Result")

    if not any([do_explain, do_debug, do_convert, do_review]):
        st.info("Choose an action on the left to get started.")

    if any([do_explain, do_debug, do_convert, do_review]):
        if not code_input.strip():
            st.warning("Please paste some code first.")
            st.stop()

    # ── Explain ────────────────────────────────────────────────────────────────
    if do_explain:
        system_msg = (
            f"You are an expert {lang} developer and patient teacher. "
            "Explain the provided code step-by-step in simple terms. "
            "Use this format:\n\n"
            "## What This Code Does\n[1-2 sentence overview]\n\n"
            "## Step-by-Step Walkthrough\n[number each logical step]\n\n"
            "## Key Concepts Used\n[bullet list of concepts with brief explanations]\n\n"
            "## Potential Gotchas\n[anything a beginner might miss]"
        )
        user_msg = f"Language: {lang}\n\nCode:\n```{lang.lower()}\n{code_input[:MAX_CODE_CHARS]}\n```"
        if context.strip():
            user_msg += f"\n\nContext: {context}"

        with st.spinner("Analyzing code…"):
            try:
                resp = _groq_client().chat.completions.create(
                    model=_MODEL,
                    messages=[
                        {"role": "system", "content": system_msg},
                        {"role": "user", "content": user_msg},
                    ],
                )
                st.markdown(resp.choices[0].message.content)
            except Exception as exc:
                st.error(f"Error: {exc}")

    # ── Debug ──────────────────────────────────────────────────────────────────
    if do_debug:
        system_msg = (
            f"You are a senior {lang} developer specializing in code review and debugging. "
            "Analyze the code for bugs, errors, and issues. Respond in this format:\n\n"
            "## Bug Report\n[Summary of issues found, or 'No bugs found' if clean]\n\n"
            "## Issues Found\n[List each bug with line reference and explanation]\n\n"
            "## Fixed Code\n```\n[Complete corrected code]\n```\n\n"
            "## Explanation of Fixes\n[What was changed and why]"
        )
        user_msg = f"Language: {lang}\n\nCode to debug:\n```{lang.lower()}\n{code_input[:MAX_CODE_CHARS]}\n```"
        if context.strip():
            user_msg += f"\n\nContext: {context}"

        with st.spinner("Debugging code…"):
            try:
                resp = _groq_client().chat.completions.create(
                    model=_MODEL,
                    messages=[
                        {"role": "system", "content": system_msg},
                        {"role": "user", "content": user_msg},
                    ],
                )
                st.markdown(resp.choices[0].message.content)
            except Exception as exc:
                st.error(f"Error: {exc}")

    # ── Convert pseudocode ─────────────────────────────────────────────────────
    if do_convert:
        system_msg = (
            f"You are an expert {lang} developer. Convert the pseudocode or description "
            f"into complete, working, production-quality {lang} code. "
            "Include all necessary imports. Add brief comments only where the logic is non-obvious. "
            "Respond in this format:\n\n"
            f"## {lang} Implementation\n```{lang.lower()}\n[complete working code]\n```\n\n"
            "## How to Run\n[brief setup and run instructions]\n\n"
            "## Notes\n[any assumptions made or alternative approaches]"
        )
        user_msg = f"Target language: {lang}\n\nPseudocode / description:\n{code_input[:MAX_CODE_CHARS]}"
        if context.strip():
            user_msg += f"\n\nAdditional context: {context}"

        with st.spinner("Converting to working code…"):
            try:
                resp = _groq_client().chat.completions.create(
                    model=_MODEL,
                    messages=[
                        {"role": "system", "content": system_msg},
                        {"role": "user", "content": user_msg},
                    ],
                )
                result = resp.choices[0].message.content
                st.markdown(result)
                st.download_button(
                    "Download Code",
                    data=result,
                    file_name=f"generated_code.{lang.lower()[:2]}",
                    mime="text/plain",
                )
            except Exception as exc:
                st.error(f"Error: {exc}")

    # ── Code review ────────────────────────────────────────────────────────────
    if do_review:
        system_msg = (
            f"You are a senior {lang} engineer conducting a thorough code review. "
            "Evaluate the code across multiple dimensions. Use this format:\n\n"
            "## Overall Score: [1-10]/10\n\n"
            "## Code Quality\n[readability, naming, structure]\n\n"
            "## Performance\n[time/space complexity, bottlenecks]\n\n"
            "## Security\n[any security concerns]\n\n"
            "## Best Practices\n[what follows best practices, what doesn't]\n\n"
            "## Refactored Snippet\n```\n[Show a key improvement as a code example]\n```"
        )
        user_msg = f"Language: {lang}\n\nCode:\n```{lang.lower()}\n{code_input[:MAX_CODE_CHARS]}\n```"
        if context.strip():
            user_msg += f"\n\nContext: {context}"

        with st.spinner("Reviewing code…"):
            try:
                resp = _groq_client().chat.completions.create(
                    model=_MODEL,
                    messages=[
                        {"role": "system", "content": system_msg},
                        {"role": "user", "content": user_msg},
                    ],
                )
                st.markdown(resp.choices[0].message.content)
            except Exception as exc:
                st.error(f"Error: {exc}")