import json

import gradio as gr
from pathlib import Path
from src.config import SUPPORTED_FRAMEWORKS

from src.hf_utils import load_leaderboard_data, upload_submission, check_name_exists
from src.eval import start_background_evaluation


def handle_upload(submission_name, uploaded_file, report_file, model_framework, base_llm, progress=gr.Progress()):
    """Handle file upload and start evaluation."""
    if model_framework not in SUPPORTED_FRAMEWORKS:
        return f"Unsupported modelling framework: {model_framework}. Supported frameworks are: {', '.join(SUPPORTED_FRAMEWORKS)}"

    if not uploaded_file:
        return "No file uploaded. Please upload a valid submission file."

    if report_file and not report_file.name.endswith(".pdf"):
        return "Invalid report format. Please upload a PDF file."

    # normalize the submission name
    submission_name = submission_name.strip().replace(" ", "_").lower()
    # keep only alphanumeric characters and underscores, restrict to 30 characters
    submission_name = "".join(c for c in submission_name if c.isalnum() or c == "_")[:30]

    if not submission_name or submission_name.strip() == "":
        return "Submission name is required"

    if not base_llm or base_llm.strip() == "":
        return "Base LLM is required. Please specify the base language model used for generating the models."

    if check_name_exists(submission_name):
        return f"Submission name '{submission_name}' already exists. Please choose a different name."

    try:
        progress(0.3, "Uploading to Hugging Face...")

        # Check if the file is a valid JSONL file
        if not uploaded_file.name.endswith(".jsonl"):
            return "Invalid file format. Please upload a .jsonl file."

        # Check that the keys in the JSONL file are correct ('id' and 'model')
        with open(uploaded_file.name, "r") as file:
            found_one = False
            for line in file:
                found_one = True
                json_object = json.loads(line)
                if not all(key in json_object for key in ["id", "model"]):
                    return "Invalid content. Each line must contain 'id' and 'model' keys."
            if not found_one:
                return "Empty file. Please upload a valid JSONL file."

        success, result = upload_submission(uploaded_file, submission_name, report_file, model_framework, base_llm)
        if not success:
            return f"Upload failed: {result}"

        progress(0.7, "Starting evaluation...")

        # Start evaluation
        start_background_evaluation(result)

        progress(1.0, "Process complete")
        return (
            f"✅ Submission '{submission_name}' uploaded successfully!\n"
            f"Do not worry if the leaderboard does not update immediately; "
            f"it may take some time for the results to appear (around 5-10 minutes). "
            f"Feel free to close the tab and check back later.")

    except Exception as e:
        return f"Error processing upload: {str(e)}"


def create_ui():
    """Create and return Gradio UI."""
    with gr.Blocks(title="Welcome to the CP-Bench leaderboard!") as demo:
        gr.Markdown("# CP-Bench Leaderboard")
        gr.Markdown(
            "This leaderboard is designed to evaluate LLM-generated constraint models for the problems "
            "in the [CP-Bench](https://huggingface.co/datasets/kostis-init/CP-Bench) dataset."
            "\n\n"
            "## How to Submit\n"
            "1. **Name your submission**: Choose a unique name for your submission (e.g., `my_cool_submission`). "
            "This name will be used to identify your submission on the leaderboard.\n"
            "2. **Select the modelling framework**: Indicate which modelling framework your submission uses (e.g., MiniZinc, CPMpy, OR-Tools).\n"
            "3. **Upload a PDF report**: This is optional, but we highly encourage you to upload a report "
            "   (in PDF format) describing your approach. As this is an open competition, we want to avoid submissions "
            "   that just copy the models from the dataset. The report can be a short description of your approach, "
            "   the models you generated, and any other relevant information.\n"
            "4. **Upload your submission**: Upload a **single** `.jsonl` file containing the generated models. "
            "   **Each line in the file should be a JSON object with two keys: `id` and `model`.**\n"
            "   * `id`: The ID of the problem exactly as it appears in the original dataset (e.g., `csplib__csplib_001_car_sequencing`).\n"
            "   * `model`: The generated model for the problem (as a string representing runnable code). Make sure that it eventually outputs the solution as a json with key(s) as described in the `decision_variables` entry and values as would be expected in the problem. This is part of the evaluation as well: unexpected keys, or value types are considered incorrect. This is because our automatic evaluation is based on the solution printed by the submitted models.\n"
            "   * An example submission file can be found [here](https://huggingface.co/spaces/kostis-init/CP-Bench-competition/blob/main/template_submission.jsonl).\n"
            "\n   To help you get started, we also provide a **template script [here](https://huggingface.co/spaces/kostis-init/CP-Bench-competition/blob/main/template.py)**. This script acts as a backbone, showing how to produce a simple, runnable submission for one of the problems. You can use it as a starting point for developing your own logic.\n"
            "5. **Check the leaderboard**: After uploading, it may take a few minutes for a submission to be evaluated and appear on the leaderboard.\n"
            "\n\n"
            "## Important Notes\n"
            "1. **Submission Name**: The submission name must be different from any existing submission names.\n"
            "2. **File Format**: Ensure that the uploaded files are in the correct format. The submission file must be a `.jsonl` file, and the report must be a `pdf` file.\n"
            "3. **Evaluation Script**: It is highly recommended to use the evaluation script provided [here](https://huggingface.co/spaces/kostis-init/CP-Bench-competition/blob/main/src/user_eval.py) to check your results before submission. You can run the script as follows:\n"
            "   ```bash\n"
            "   python user_eval.py --submission_file path/to/my/submission.jsonl --modelling_framework CPMpy\n"
            "   ```\n"
            "   This will evaluate your submission locally and print the results to the console.\n"
            "4. **Modelling Frameworks**: Currently, the supported modelling frameworks are MiniZinc, CPMpy and OR-Tools. More frameworks can be added (feel free to submit pull requests).\n"
            "\n\n"
            "### If you have any questions or issues, feel free to reach out to us.\n"
            "---\n"
        )

        with gr.Row():
            with gr.Column(scale=1):
                gr.Markdown("## 📤 Upload Submission")

                submission_name = gr.Textbox(
                    label="Submission Name (required)",
                    placeholder="Enter a unique name for your submission",
                    interactive=True,
                    info="This name will appear on the leaderboard. It is recommended that it represents the approach you used to generate the models (e.g. 'smart_prompting')",
                )
                model_framework = gr.Dropdown(
                    label="Modelling Framework (required)",
                    choices=SUPPORTED_FRAMEWORKS,
                    value=None,
                    multiselect=False,
                    interactive=True,
                    info="Select the modelling framework used for your submission.",
                    allow_custom_value=False,
                    filterable=False,
                )
                base_llm = gr.Textbox(
                    label="Base LLM (required)",
                    placeholder="Enter the base LLM used for generating the models (e.g., GPT-4, Llama-3.3)",
                    interactive=True,
                    info="The base LLM used for generating the models."
                )

                with gr.Row():
                    report_file = gr.File(
                        label="Upload PDF Report (optional, but recommended)",
                        file_types=[".pdf"],
                        file_count="single",
                        interactive=True,
                    )
                    submission_file = gr.File(
                        label="Upload Submission File (required, .jsonl)",
                        file_types=[".jsonl"],
                        file_count="single",
                        interactive=True,
                    )
                upload_button = gr.Button("Click to Upload Submission")
                status_box = gr.Textbox(label="Status", interactive=False)

            with gr.Column(scale=2):
                gr.Markdown("## 🏆 Results Leaderboard")
                leaderboard = gr.DataFrame(value=load_leaderboard_data, interactive=False)
                refresh_button = gr.Button("🔄 Refresh Leaderboard")

        # Event handlers
        upload_button.click(
            fn=handle_upload,
            inputs=[submission_name, submission_file, report_file, model_framework, base_llm],
            outputs=[status_box],
            show_progress="full",
        )

        refresh_button.click(
            fn=load_leaderboard_data,
            inputs=None,
            outputs=[leaderboard]
        )

        gr.Markdown(
            "### If you found our work useful, please consider citing our paper and dataset as follows:\n"
            "```bibtex\n"
            "@dataset{michailidis_2025_15592407,\n"
            "author       = {Michailidis, Kostis and Tsouros, Dimosthenis and Guns, Tias},\n"
            "title        = {CP-Bench},\n"
            "month        = jun,\n"
            "year         = 2025,\n"
            "publisher    = {Zenodo},\n"
            "version      = {1.0.0},\n"
            "doi          = {10.5281/zenodo.15592407},\n"
            "url          = {https://doi.org/10.5281/zenodo.15592407},\n"
            "}"
        )

    return demo