import os
import sys
import re
import json
import requests

platform = os.environ.get("PLATFORM", "github").lower()
token = os.environ["TOKEN"]
owner = os.environ["REPO_OWNER"]
repo = os.environ["REPO_NAME"]
pr_index = os.environ["PR_INDEX"]
api_url = os.environ.get("API_URL")
diff_text = os.environ.get("DIFF")
comment_template = os.environ.get("COMMENT_TEMPLATE", "")

if not diff_text:
    print("No diff provided", file=sys.stderr)
    sys.exit(1)

# Parse diff
diff_files = {}
current_file = None
new_line_num = None

for line in diff_text.splitlines():
    if line.startswith("+++ b/"):
        current_file = line[6:].strip()
        diff_files[current_file] = []
        new_line_num = 0
    elif line.startswith("@@"):
        m = re.match(r"@@ -\d+(?:,\d+)? \+(\d+)(?:,(\d+))? @@", line)
        if m:
            new_line_num = int(m.group(1)) - 1
    elif line.startswith("+") and not line.startswith("+++"):
        new_line_num += 1
        content = line[1:]
        diff_files[current_file].append((new_line_num, content))
    elif not line.startswith("-"):
        new_line_num += 1

# Post comments
for file_path, lines in diff_files.items():
    if not lines:
        continue
    all_lines_content = "\n".join([line_content for _, line_content in lines])
    for line_number, line_content in lines:
        body = comment_template.replace("{line}", line_content).replace("{lines}", all_lines_content)

        if platform == "github":
            url = f"https://api.github.com/repos/{owner}/{repo}/issues/{pr_index}/comments"
            payload = {"body": body}
            if file_path and line_number:
                url = f"https://api.github.com/repos/{owner}/{repo}/pulls/{pr_index}/comments"
                payload.update({
                    "body": body,
                    "path": file_path,
                    "position": line_number
                })
        elif platform == "gitea":
            if not api_url:
                print("Gitea API URL required", file=sys.stderr)
                sys.exit(1)
            url = f"{api_url}/repos/{owner}/{repo}/pulls/{pr_index}/comments"
            payload = {"body": body}
            if file_path and line_number:
                payload.update({
                    "path": file_path,
                    "position": line_number
                })
        else:
            print(f"Unsupported platform: {platform}", file=sys.stderr)
            sys.exit(1)

        headers = {
            "Authorization": f"token {token}",
            "Content-Type": "application/json",
        }

        resp = requests.post(url, headers=headers, json=payload)
        if resp.status_code in (201, 200):
            print(f"Comment posted on {file_path}:{line_number}")
        else:
            print(f"Failed to post comment on {file_path}:{line_number} ({resp.status_code})", file=sys.stderr)
            print(resp.text, file=sys.stderr)