#!/usr/bin/env python

import sys
import re
import readline
import traceback
import argparse
from rich.console import Console
from colorama import Fore, Style
from rich.live import Live
from rich.text import Text
from rich.markdown import Markdown

from tqdm import tqdm

from pathlib import Path

import os
import openai

from dump import dump

import prompts

history_file = ".coder.history"
try:
    readline.read_history_file(history_file)
except FileNotFoundError:
    pass

openai.api_key = os.getenv("OPENAI_API_KEY")


def find_index(list1, list2):
    for i in range(len(list1)):
        if list1[i : i + len(list2)] == list2:
            return i
    return -1


class Coder:
    fnames = dict()
    last_modified = 0

    def __init__(self, use_gpt_4, files, pretty):
        if use_gpt_4:
            self.main_model = "gpt-4"
        else:
            self.main_model = "gpt-3.5-turbo"

        for fname in files:
            self.fnames[fname] = Path(fname).stat().st_mtime

        self.check_for_local_edits(True)

        self.pretty = pretty

        if pretty:
            self.console = Console()
        else:
            self.console = Console(force_terminal=True, no_color=True)

    def files_modified(self):
        for fname, mtime in self.fnames.items():
            if Path(fname).stat().st_mtime != mtime:
                return True

    def request(self, prompt):
        self.request_prompt = prompt

    def quoted_file(self, fname):
        prompt = "\n"
        prompt += fname
        prompt += "\n```\n"
        prompt += Path(fname).read_text()
        prompt += "\n```\n"
        return prompt

    def get_files_content(self):
        prompt = ""
        for fname in self.fnames:
            prompt += self.quoted_file(fname)
        return prompt

    def get_input(self):
        if self.pretty:
            self.console.rule()
        else:
            print()

        inp = ""
        if self.pretty:
            print(Fore.GREEN, end="\r")
        else:
            print()

        while not inp.strip():
            try:
                inp = input("> ")
            except EOFError:
                return

        ###
        if self.pretty:
            print(Style.RESET_ALL)
        else:
            print()

        readline.write_history_file(history_file)
        return inp

    def check_for_local_edits(self, init=False):
        last_modified = max(Path(fname).stat().st_mtime for fname in self.fnames)
        since = last_modified - self.last_modified
        self.last_modified = last_modified
        if init:
            return
        if since > 0:
            return True
        return False

    def get_files_messages(self):
        files_content = prompts.files_content_prefix
        files_content += self.get_files_content()

        files_messages = [
            dict(role="user", content=files_content),
            dict(role="assistant", content="Ok."),
            dict(
                role="system",
                content=prompts.files_content_suffix + prompts.system_reminder,
            ),
        ]

        return files_messages

    def run(self):
        self.done_messages = []
        self.cur_messages = []

        self.num_control_c = 0

        while True:
            try:
                self.run_loop()
            except KeyboardInterrupt:
                self.num_control_c += 1
                if self.num_control_c >= 2:
                    break
                self.console.print("[bold red]^C again to quit")

        if self.pretty:
            print(Style.RESET_ALL)

    def run_loop(self):
        inp = self.get_input()
        if inp is None:
            return

        self.num_control_c = 0

        if self.check_for_local_edits():
            # files changed, move cur messages back behind the files messages
            self.done_messages += self.cur_messages
            self.done_messages += [
                dict(role="user", content=prompts.files_content_local_edits),
                dict(role="assistant", content="Ok."),
            ]
            self.cur_messages = []

        self.cur_messages += [
            dict(role="user", content=inp),
        ]

        messages = [
            dict(role="system", content=prompts.main_system + prompts.system_reminder),
        ]
        messages += self.done_messages
        messages += self.get_files_messages()
        messages += self.cur_messages

        # self.show_messages(messages, "all")

        content, interrupted = self.send(messages)
        if interrupted:
            content += "\n^C KeyboardInterrupt"

        self.cur_messages += [
            dict(role="assistant", content=content),
        ]

        self.console.print()
        if interrupted:
            return True

        try:
            edited = self.update_files(content, inp)
        except Exception as err:
            print(err)
            print()
            traceback.print_exc()
            edited = None

        if not edited:
            return True

        self.check_for_local_edits(True)
        self.done_messages += self.cur_messages
        self.done_messages += [
            dict(role="user", content=prompts.files_content_gpt_edits),
            dict(role="assistant", content="Ok."),
        ]
        self.cur_messages = []
        return True

    def show_messages(self, messages, title):
        print(title.upper(), "*" * 50)

        for msg in messages:
            print()
            print("-" * 50)
            role = msg["role"].upper()
            content = msg["content"].splitlines()
            for line in content:
                print(role, line)

    def send(self, messages, model=None, show_progress=0):
        # self.show_messages(messages, "all")

        if not model:
            model = self.main_model

        completion = openai.ChatCompletion.create(
            model=model,
            messages=messages,
            temperature=0,
            stream=True,
        )

        interrupted = False
        try:
            if show_progress:
                self.show_send_progress(completion, show_progress)
            elif self.pretty:
                self.show_send_output_color(completion)
            else:
                self.show_send_output_plain(completion)
        except KeyboardInterrupt:
            interrupted = True

        return self.resp, interrupted

    def show_send_progress(self, completion, show_progress):
        self.resp = ""
        pbar = tqdm(total=show_progress)
        for chunk in completion:
            try:
                text = chunk.choices[0].delta.content
                self.resp += text
            except AttributeError:
                continue

            pbar.update(len(text))

        pbar.update(show_progress)
        pbar.close()

    def show_send_output_plain(self, completion):
        self.resp = ""

        for chunk in completion:
            if chunk.choices[0].finish_reason not in (None, "stop"):
                dump(chunk.choices[0].finish_reason)
            try:
                text = chunk.choices[0].delta.content
                self.resp += text
            except AttributeError:
                continue

            sys.stdout.write(text)
            sys.stdout.flush()

    def show_send_output_color(self, completion):
        self.resp = ""

        with Live(vertical_overflow="scroll") as live:
            for chunk in completion:
                if chunk.choices[0].finish_reason not in (None, "stop"):
                    assert False, "Exceeded context window!"
                try:
                    text = chunk.choices[0].delta.content
                    self.resp += text
                except AttributeError:
                    continue

                md = Markdown(self.resp, style="blue", code_theme="default")
                live.update(md)

            live.update(Text(""))
            live.stop()

        md = Markdown(self.resp, style="blue", code_theme="default")
        self.console.print(md)

    pattern = re.compile(
        r"(\S+)\s+(```\s*)?<<<<<<< ORIGINAL\n(.*?\n?)=======\n(.*?\n?)>>>>>>> UPDATED",
        re.MULTILINE | re.DOTALL,
    )

    def update_files(self, content, inp):
        edited = set()
        for match in self.pattern.finditer(content):
            path, _, original, updated = match.groups()

            edited.add(path)
            if self.do_replace(path, original, updated):
                continue
            edit = match.group()
            self.do_gpt_powered_replace(path, edit, inp)

        return edited

    def do_replace(self, fname, before_text, after_text):
        before_text = self.strip_quoted_wrapping(before_text, fname)
        after_text = self.strip_quoted_wrapping(after_text, fname)

        fname = Path(fname)

        # does it want to make a new file?
        if not fname.exists() and not before_text:
            print("Creating empty file:", fname)
            fname.touch()

        content = fname.read_text().splitlines()

        if not before_text and not content:
            # first populating an empty file
            new_content = after_text
        else:
            before_lines = [line.strip() for line in before_text.splitlines()]
            stripped_content = [line.strip() for line in content]
            where = find_index(stripped_content, before_lines)

            if where < 0:
                return

            new_content = content[:where]
            new_content += after_text.splitlines()
            new_content += content[where + len(before_lines) :]
            new_content = "\n".join(new_content) + "\n"

        fname.write_text(new_content)
        self.console.print(f"Applied edit to {fname}")
        return True

    def do_gpt_powered_replace(self, fname, edit, request):
        model = "gpt-3.5-turbo"
        print(f"Asking {model} to apply ambiguous edit to {fname}...")

        fname = Path(fname)
        content = fname.read_text()
        prompt = prompts.editor_user.format(
            request=request,
            edit=edit,
            fname=fname,
            content=content,
        )

        messages = [
            dict(role="system", content=prompts.editor_system),
            dict(role="user", content=prompt),
        ]
        res, interrupted = self.send(
            messages, show_progress=len(content) + len(edit) / 2, model=model
        )
        if interrupted:
            return

        res = self.strip_quoted_wrapping(res, fname)
        fname.write_text(res)

    def strip_quoted_wrapping(self, res, fname=None):
        if not res:
            return res

        res = res.splitlines()

        if fname and res[0].strip().endswith(Path(fname).name):
            res = res[1:]

        if res[0].startswith("```") and res[-1].startswith("```"):
            res = res[1:-1]

        res = "\n".join(res)
        if res and res[-1] != "\n":
            res += "\n"

        return res


def main():
    parser = argparse.ArgumentParser(description="Chat with GPT about code")
    parser.add_argument(
        "files", metavar="FILE", nargs="+", help="a list of source code files"
    )
    parser.add_argument(
        "-3",
        "--gpt-3-5-turbo",
        action="store_true",
        help="Only use gpt-3.5-turbo, not gpt-4",
    )
    parser.add_argument(
        "--no-pretty",
        action="store_false",
        dest="pretty",
        default=True,
        help="Disable prettyd output of GPT responses",
    )
    parser.add_argument(
        "--apply",
        metavar="FILE",
        help="Apply the changes from the given file instead of running the chat",
    )

    args = parser.parse_args()

    use_gpt_4 = not args.gpt_3_5_turbo
    fnames = args.files
    pretty = args.pretty

    coder = Coder(use_gpt_4, fnames, pretty)
    if args.apply:
        with open(args.apply, "r") as f:
            content = f.read()
        coder.update_files(content, inp="")
    else:
        coder.run()


if __name__ == "__main__":
    status = main()
    sys.exit(status)