from pathlib import Path

from flask import Flask, jsonify, render_template, request, send_file
from werkzeug.exceptions import RequestEntityTooLarge

from aging_tool.service import (
    AgingSummaryError,
    AnalysisTaskNotFound as AgingTaskNotFound,
    get_task_status as get_aging_task_status,
    start_analysis_task as start_aging_analysis_task,
)
from keyword_tool.service import (
    AnalysisTaskNotFound as KeywordTaskNotFound,
    KeywordSummaryError,
    get_task_status as get_keyword_task_status,
    start_analysis_task as start_keyword_analysis_task,
)
from sguid_tool.processor import ProcessingError
from sguid_tool.service import (
    AnalysisTaskNotFound as SguidTaskNotFound,
    get_task_status as get_sguid_task_status,
    start_analysis_task as start_sguid_analysis_task,
)
from sguid_tool.stats import get_usage_stats, record_usage


BASE_DIR = Path(__file__).resolve().parent


def create_app() -> Flask:
    app = Flask(__name__)
    app.config["MAX_CONTENT_LENGTH"] = 100 * 1024 * 1024
    app.config["UPLOAD_FOLDER"] = BASE_DIR / "uploads"
    app.config["OUTPUT_FOLDER"] = BASE_DIR / "saved_outputs"
    app.config["DATA_FOLDER"] = BASE_DIR / "data"
    app.config["KEYWORD_UPLOAD_FOLDER"] = BASE_DIR / "uploads" / "keyword_summary"
    app.config["KEYWORD_OUTPUT_FOLDER"] = BASE_DIR / "saved_outputs" / "keyword_summary"
    app.config["AGING_UPLOAD_FOLDER"] = BASE_DIR / "uploads" / "aging_stock_summary"
    app.config["AGING_OUTPUT_FOLDER"] = BASE_DIR / "saved_outputs" / "aging_stock_summary"

    for key in [
        "UPLOAD_FOLDER",
        "OUTPUT_FOLDER",
        "DATA_FOLDER",
        "KEYWORD_UPLOAD_FOLDER",
        "KEYWORD_OUTPUT_FOLDER",
        "AGING_UPLOAD_FOLDER",
        "AGING_OUTPUT_FOLDER",
    ]:
        app.config[key].mkdir(parents=True, exist_ok=True)

    @app.get("/")
    def index():
        return render_template("index.html", active_nav="sgu")

    @app.get("/keyword-summary")
    def keyword_summary():
        return render_template("keyword_summary.html", active_nav="keyword")

    @app.get("/placement-summary")
    def placement_summary():
        return render_template("keyword_summary.html", active_nav="placement")

    @app.get("/aging-stock")
    def aging_stock():
        return render_template("aging_stock.html", active_nav="aging")

    @app.get("/api/stats")
    def stats():
        return jsonify(get_usage_stats(app.config["DATA_FOLDER"]))

    @app.post("/api/process")
    def process_file():
        uploaded_file = request.files.get("file")
        if not uploaded_file or not uploaded_file.filename:
            return jsonify({"success": False, "error": "请选择一个 .xlsx 或 .csv 文件。"}), 400

        record_usage(app.config["DATA_FOLDER"])

        try:
            task_id = start_sguid_analysis_task(
                uploaded_file=uploaded_file,
                upload_dir=app.config["UPLOAD_FOLDER"],
                output_dir=app.config["OUTPUT_FOLDER"],
            )
        except ProcessingError as exc:
            return jsonify({"success": False, "error": str(exc)}), 400

        return jsonify({"success": True, "task_id": task_id, "message": "文件上传成功，正在生成 SGU 汇总结果..."})

    @app.get("/api/process/status/<task_id>")
    def process_file_status(task_id: str):
        try:
            return jsonify(get_sguid_task_status(task_id))
        except SguidTaskNotFound as exc:
            return jsonify({"success": False, "error": str(exc)}), 404

    @app.get("/api/process/download/<filename>")
    def process_file_download(filename: str):
        file_path = app.config["OUTPUT_FOLDER"] / filename
        if not file_path.exists():
            return jsonify({"success": False, "error": "结果文件不存在。"}), 404

        return send_file(
            file_path,
            as_attachment=True,
            download_name=filename,
            mimetype="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
        )

    @app.post("/keyword-summary/api/upload")
    @app.post("/placement-summary/api/upload")
    def keyword_summary_upload():
        uploaded_file = request.files.get("file")
        if not uploaded_file or not uploaded_file.filename:
            return jsonify({"success": False, "error": "请选择一个 Excel 或 CSV 文件。"}), 400

        record_usage(app.config["DATA_FOLDER"])

        try:
            task_id = start_keyword_analysis_task(
                uploaded_file=uploaded_file,
                upload_dir=app.config["KEYWORD_UPLOAD_FOLDER"],
                output_dir=app.config["KEYWORD_OUTPUT_FOLDER"],
            )
        except KeywordSummaryError as exc:
            return jsonify({"success": False, "error": str(exc)}), 400

        return jsonify(
            {
                "success": True,
                "task_id": task_id,
                "message": "文件上传成功，正在生成搜索词与投放词汇总...",
            }
        )

    @app.get("/keyword-summary/api/status/<task_id>")
    @app.get("/placement-summary/api/status/<task_id>")
    def keyword_summary_status(task_id: str):
        try:
            return jsonify(get_keyword_task_status(task_id))
        except KeywordTaskNotFound as exc:
            return jsonify({"success": False, "error": str(exc)}), 404

    @app.get("/keyword-summary/api/download/<filename>")
    @app.get("/placement-summary/api/download/<filename>")
    def keyword_summary_download(filename: str):
        file_path = app.config["KEYWORD_OUTPUT_FOLDER"] / filename
        if not file_path.exists():
            return jsonify({"success": False, "error": "结果文件不存在。"}), 404

        return send_file(
            file_path,
            as_attachment=True,
            download_name=filename,
            mimetype="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
        )

    @app.post("/aging-stock/api/upload")
    def aging_stock_upload():
        uploaded_file = request.files.get("file")
        if not uploaded_file or not uploaded_file.filename:
            return jsonify({"success": False, "error": "请选择库龄 Excel 或 CSV 文件。"}), 400

        record_usage(app.config["DATA_FOLDER"])

        try:
            task_id = start_aging_analysis_task(
                uploaded_file=uploaded_file,
                upload_dir=app.config["AGING_UPLOAD_FOLDER"],
                output_dir=app.config["AGING_OUTPUT_FOLDER"],
            )
        except AgingSummaryError as exc:
            return jsonify({"success": False, "error": str(exc)}), 400

        return jsonify({"success": True, "task_id": task_id, "message": "文件上传成功，正在汇总超龄库存数据..."})

    @app.get("/aging-stock/api/status/<task_id>")
    def aging_stock_status(task_id: str):
        try:
            return jsonify(get_aging_task_status(task_id))
        except AgingTaskNotFound as exc:
            return jsonify({"success": False, "error": str(exc)}), 404

    @app.get("/aging-stock/api/download/<filename>")
    def aging_stock_download(filename: str):
        file_path = app.config["AGING_OUTPUT_FOLDER"] / filename
        if not file_path.exists():
            return jsonify({"success": False, "error": "结果文件不存在。"}), 404

        return send_file(
            file_path,
            as_attachment=True,
            download_name=filename,
            mimetype="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
        )

    @app.errorhandler(RequestEntityTooLarge)
    def handle_large_file(_error):
        return jsonify({"message": "上传文件过大，当前限制为 100MB，请压缩源文件后重试。"}), 413

    return app


app = create_app()


if __name__ == "__main__":
    app.run(host="0.0.0.0", port=5001, debug=True)