import json
import os
import tkinter as tk
from tkinter import ttk

import pandas as pd
import rasterio
from PIL import Image, ImageTk


class DatasetTreeViewer(tk.Tk):
    def __init__(self, host_name):
        super().__init__()
        self.title("Dataset Viewer — © Earth Rover Program, 2025")
        self.geometry("1200x700")
        self.base_path = os.path.join("datasets", host_name)
        self.datasets = self.get_datasets(host_name)

        # === Layout ===
        paned = tk.PanedWindow(self, orient=tk.HORIZONTAL, sashrelief=tk.RAISED, sashwidth=6)
        paned.pack(fill=tk.BOTH, expand=True)

        left_frame = tk.Frame(paned)
        right_frame = tk.Frame(paned)
        paned.add(left_frame)
        paned.paneconfigure(left_frame, minsize=300)
        paned.add(right_frame)

        bottom_frame = tk.Frame(self)
        bottom_frame.pack(fill=tk.X)

        # === Checkbox grid above Treeview (2x2 layout)
        checkbox_outer_frame = tk.Frame(left_frame)
        checkbox_outer_frame.pack(pady=4)

        self.status_filters = {}
        default_checked = {"PROCESSED"}
        status_options = ["UNEXAMINED", "SKIPPED", "REQUESTED", "DOWNLOADED", "PROCESSED"]

        for idx, status in enumerate(status_options):
            row = idx // 2
            col = idx % 2
            var = tk.BooleanVar(value=status in default_checked)
            cb = tk.Checkbutton(
                checkbox_outer_frame,
                text=status.capitalize(),
                variable=var,
                command=self.build_tree,
                anchor="w",
                width=15,  # fixed width for alignment
                padx=0
            )
            cb.grid(row=row, column=col, sticky="w")
            self.status_filters[status] = var

        # === Treeview
        self.tree = ttk.Treeview(left_frame)
        self.tree.heading("#0", text=f"Datasets from {host_name.upper()}")
        self.tree.pack(fill=tk.BOTH, expand=True)
        self.tree.bind("<<TreeviewSelect>>", self.on_tree_select)

        # === Viewer frame
        self.viewer_frame = tk.Frame(right_frame)
        self.viewer_frame.pack(fill=tk.BOTH, expand=True)

        # === Bottom info
        self.info_text = tk.Text(bottom_frame, height=10, wrap=tk.WORD)
        self.info_text.pack(fill=tk.X)

        self.build_tree()

    def get_datasets(self, host_name):
        status_path = os.path.join("src", host_name, "status.json")
        datasets = {}

        try:
            with open(status_path, "r") as f:
                items = json.load(f)

            for item in items:
                name = item["name"]
                dataset_path = os.path.join(self.base_path, name)
                processed_path = os.path.join(dataset_path, "processed")

                if not os.path.exists(processed_path):
                    continue

                file_list = []
                for root, _, files in os.walk(processed_path):
                    for f in files:
                        if f.endswith((".csv", ".png", ".tif", ".tiff", ".json", ".txt")):
                            full_path = os.path.join(root, f)
                            rel_path = os.path.relpath(full_path, processed_path)
                            file_list.append(rel_path)

                datasets[name] = {
                    "name": name,
                    "title": item.get("title", ""),
                    "abstract": item.get("abstract") or "",
                    "request_needed": item.get("request_needed", False),
                    "status": item.get("status"),
                    "notes": item.get("notes"),
                    "screened_by": item.get("screened_by"),
                    "requested_downloaded_by": item.get("requested_downloaded_by"),
                    "processed_by": item.get("processed_by"),
                    "files": sorted(file_list),
                    "path": dataset_path
                }
        except Exception as e:
            print(f"Error reading {status_path}: {e}")

        return datasets

    def build_tree(self):
        self.tree.delete(*self.tree.get_children())
        selected_statuses = {k for k, v in self.status_filters.items() if v.get()}

        for dataset_name, data in self.datasets.items():
            if data.get("status") not in selected_statuses:
                continue

            dataset_node = self.tree.insert("", "end", text=dataset_name, open=False)
            node_map = {"": dataset_node}

            for rel_path in data["files"]:
                parts = rel_path.split(os.sep)
                current = dataset_node
                for i, part in enumerate(parts):
                    sub_path = os.path.join(*parts[:i + 1])
                    if sub_path not in node_map:
                        node_map[sub_path] = self.tree.insert(current, "end", text=part, open=False)
                    current = node_map[sub_path]

    def on_tree_select(self, event):
        selected_id = self.tree.focus()
        item = self.tree.item(selected_id)
        text = item["text"]
        parent_id = self.tree.parent(selected_id)

        if parent_id == "":
            dataset_name = text
            data = self.datasets[dataset_name]
            self.info_text.delete(1.0, tk.END)
            lines = [
                f"Name: {data['name']}",
                f"Title: {data['title']}",
            ]
            if data.get("abstract"):
                lines.append(f"Abstract: {data['abstract']}")
            lines.append(f"Request needed: {data['request_needed']}")
            lines.append(f"Status: {data['status']}")
            if data['notes'] is not None:
                lines.append(f"Notes: {data['notes']}")
            self.info_text.insert(tk.END, "\n".join(lines))
            self.clear_viewer()
            return

        # Traverse upward to get dataset name
        full_path_parts = []
        current_id = selected_id
        while True:
            parent = self.tree.parent(current_id)
            if parent == "":
                dataset_name = self.tree.item(current_id)["text"]
                break
            full_path_parts.insert(0, self.tree.item(current_id)["text"])
            current_id = parent

        rel_file_path = os.path.join(*full_path_parts)
        full_file_path = os.path.join(self.datasets[dataset_name]["path"], "processed", rel_file_path)

        self.info_text.delete(1.0, tk.END)

        if os.path.isdir(full_file_path):
            self.info_text.insert(tk.END, f"Directory: {rel_file_path} from dataset: {dataset_name}\n")
            self.clear_viewer()
        else:
            self.info_text.insert(tk.END, f"File: {rel_file_path} from dataset: {dataset_name}\n")
            self.load_file(full_file_path)

    def clear_viewer(self):
        for widget in self.viewer_frame.winfo_children():
            widget.destroy()

    def load_file(self, path):
        self.clear_viewer()

        if path.endswith(".csv"):
            try:
                df = pd.read_csv(path, low_memory=False)
                self.show_csv(df)
                self.info_text.insert(tk.END, f"Number of entries: {len(df)}\n")
            except Exception as e:
                self.info_text.insert(tk.END, f"Error reading CSV:\n{e}")

        elif path.endswith(".png"):
            try:
                self.viewer_frame.update_idletasks()
                frame_w = self.viewer_frame.winfo_width()
                frame_h = self.viewer_frame.winfo_height()

                img = Image.open(path)
                img_w, img_h = img.size

                ratio_w = frame_w / img_w
                ratio_h = frame_h / img_h
                scale = min(ratio_w, ratio_h)

                new_w = int(img_w * scale)
                new_h = int(img_h * scale)
                resized = img.resize((new_w, new_h), Image.LANCZOS)
                photo = ImageTk.PhotoImage(resized)

                label = tk.Label(self.viewer_frame, image=photo)
                label.image = photo
                label.pack(expand=True)
                self.info_text.insert(tk.END, f"Shape: {img_h}x{img_w}\n")
            except Exception as e:
                self.info_text.insert(tk.END, f"Error displaying PNG:\n{e}")

        elif path.endswith(".json"):
            try:
                with open(path, "r") as f:
                    content = json.load(f)
                text_widget = tk.Text(self.viewer_frame, wrap=tk.NONE)
                text_widget.insert(tk.END, json.dumps(content, indent=2))
                text_widget.configure(state="disabled")
                text_widget.pack(fill=tk.BOTH, expand=True)
            except Exception as e:
                self.info_text.insert(tk.END, f"Error reading JSON:\n{e}")

        elif path.endswith(".tif"):
            try:
                with rasterio.open(path) as src:
                    shape = (src.height, src.width)
                    dtype = src.dtypes[0]
                    nodata = src.nodata
                    crs = src.crs
                    transform = src.transform

                summary = [
                    f"Shape: {shape}",
                    f"Datatype: {dtype}",
                    f"NoData value: {nodata}",
                    f"CRS: {crs}",
                    f"Transform:\n{transform}",
                ]

                text_widget = tk.Text(self.viewer_frame, wrap=tk.NONE)
                text_widget.insert(tk.END, "\n".join(summary))
                text_widget.configure(state="disabled")
                text_widget.pack(fill=tk.BOTH, expand=True)

            except Exception as e:
                self.info_text.insert(tk.END, f"Error reading TIF:\n{e}")

        else:
            try:
                with open(path, "r", encoding="utf-8") as f:
                    content = f.read()
                text_widget = tk.Text(self.viewer_frame, wrap=tk.NONE)
                text_widget.insert(tk.END, content)
                text_widget.configure(state="disabled")
                text_widget.pack(fill=tk.BOTH, expand=True)
            except Exception as e:
                self.info_text.insert(tk.END, f"Unsupported format for quick view: {os.path.basename(path)}\n")

    def show_csv(self, df):
        df = df.head(100)
        table = ttk.Treeview(self.viewer_frame, show="headings")
        table.pack(fill=tk.BOTH, expand=True)

        scroll_y = tk.Scrollbar(self.viewer_frame, orient="vertical", command=table.yview)
        scroll_y.pack(side=tk.RIGHT, fill=tk.Y)

        scroll_x = tk.Scrollbar(self.viewer_frame, orient="horizontal", command=table.xview)
        scroll_x.pack(side=tk.BOTTOM, fill=tk.X)

        table.configure(yscrollcommand=scroll_y.set, xscrollcommand=scroll_x.set)
        table["columns"] = list(df.columns)

        for col in df.columns:
            col_values = df[col].astype(str).head(20).tolist()
            max_len = max([len(col)] + [len(val) for val in col_values])
            width_px = max(80, min(400, max_len * 7))
            table.heading(col, text=col)
            table.column(col, width=width_px, anchor="w", stretch=False)

        for _, row in df.iterrows():
            values = [self.format_value(val) for val in row]
            table.insert("", "end", values=values)

    @staticmethod
    def format_value(val):
        if isinstance(val, float):
            return f"{val:.6g}"
        return str(val)


# === Run Viewer ===
if __name__ == "__main__":
    host_name_ = "esdac"
    app = DatasetTreeViewer(host_name_)
    try:
        icon = tk.PhotoImage(file="resources/viewer.png")
        app.iconphoto(True, icon)
    except Exception as ex:
        print("Failed to load icon:", ex)
    app.mainloop()