#!/usr/bin/env python3
"""Isolated PTY frontend checks; never submit a prompt or restart an existing server."""
import argparse
import json
import os
from pathlib import Path
import re
import shutil
import subprocess
import tempfile
import time
import unicodedata


def palette_color(index):
    basic = [(0, 0, 0), (128, 0, 0), (0, 128, 0), (128, 128, 0), (0, 0, 128), (128, 0, 128), (0, 128, 128), (192, 192, 192), (128, 128, 128), (255, 0, 0), (0, 255, 0), (255, 255, 0), (0, 0, 255), (255, 0, 255), (0, 255, 255), (255, 255, 255)]
    if index < 16:
        return basic[index]
    if index < 232:
        value = index - 16
        levels = [0, 95, 135, 175, 215, 255]
        return levels[value // 36], levels[(value // 6) % 6], levels[value % 6]
    return (8 + (index - 232) * 10,) * 3


def color_matches(prefix, wanted):
    fg = None
    for seq in re.findall(r"\x1b\[([0-9;]*)m", prefix):
        values = [int(n or 0) for n in seq.split(";")]
        i = 0
        while i < len(values):
            n = values[i]
            if n in (0, 39):
                fg = None
            elif n == 38 and values[i + 1:i + 2] == [5] and len(values) > i + 2:
                fg = palette_color(values[i + 2])
                i += 2
            elif n == 38 and values[i + 1:i + 2] == [2] and len(values) > i + 4:
                fg = tuple(values[i + 2:i + 5])
                i += 4
            elif 30 <= n <= 37:
                fg = palette_color(n - 30)
            elif 90 <= n <= 97:
                fg = palette_color(n - 90 + 8)
            i += 1
    return fg == wanted


def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("--label", required=True, help="Approved expected execution-server label, not the terminal hostname")
    parser.add_argument("--color", required=True, help="#RRGGBB")
    parser.add_argument("--model-text", required=True, help="Text visibly identifying the selected model")
    parser.add_argument("--directory-text", default="~")
    parser.add_argument("--opencode", default=shutil.which("opencode") or str(Path.home() / ".opencode/bin/opencode"))
    parser.add_argument("--session", help="Existing idle session; omitted means only home checks")
    parser.add_argument("--conversation-text", help="Visible title/text proving that --session opened a conversation, not home")
    parser.add_argument("--server", help="Explicit remote server; normal OpenCode authentication is retained")
    parser.add_argument("--standalone", action="store_true", help="For an explicitly isolated test sandbox only")
    parser.add_argument("--output", type=Path, required=True, help="Private local evidence directory; may contain screen text")
    args = parser.parse_args()
    if not re.fullmatch(r"#[0-9a-fA-F]{6}", args.color):
        parser.error("--color must be #RRGGBB")
    if args.server and args.standalone:
        parser.error("--server and --standalone cannot be combined")
    if args.session and not args.conversation_text:
        parser.error("--session requires --conversation-text to avoid falsely passing a home screen as a conversation")
    if not shutil.which("tmux"):
        parser.error("tmux is needed only for this verifier, not for the installed footer")
    os.umask(0o077)
    args.output.mkdir(mode=0o700, parents=True, exist_ok=True)
    if args.output.is_symlink() or args.output.stat().st_uid != os.getuid() or args.output.stat().st_mode & 0o077:
        parser.error("Evidence directory must be private, non-symlinked and owned by the current user")
    esc = re.compile(r"\x1b\[[0-?]*[ -/]*[@-~]")
    rgb = tuple(bytes.fromhex(args.color[1:]))
    results = []
    # A short socket path is required by Unix-domain socket length limits.
    with tempfile.TemporaryDirectory(prefix="identity-pty-") as temporary:
        socket = str(Path(temporary) / "tmux.sock")

        def tmux(*command, check=True):
            return subprocess.run(["tmux", "-S", socket, *command], text=True, capture_output=True, check=check, timeout=10).stdout

        def columns(line):
            return sum(0 if unicodedata.combining(c) else 2 if unicodedata.east_asian_width(c) in "WF" else 1 for c in line)

        try:
            for width in (80, 120):
                for view in (["home", "conversation"] if args.session else ["home"]):
                    name = f"{view}-{width}"
                    command = [args.opencode]
                    if args.server:
                        command += ["--server", args.server]
                    if args.standalone:
                        command += ["--standalone"]
                    if view == "conversation":
                        command += ["--session", args.session]
                    tmux("-f", "/dev/null", "new-session", "-d", "-s", name, "-x", str(width), "-y", "32", "-c", str(Path.cwd()), *command)
                    tmux("set-option", "-g", "status", "off")
                    deadline = time.monotonic() + 45
                    while True:
                        capture = tmux("capture-pane", "-p", "-e", "-t", name)
                        plain = esc.sub("", capture)
                        if args.label in plain and args.model_text in plain and (view == "home" or args.conversation_text in plain):
                            break
                        if time.monotonic() > deadline:
                            (args.output / f"{name}-failed.ansi").write_text(capture)
                            raise AssertionError(f"{name}: label/model missing; private capture retained")
                        time.sleep(.25)
                    (args.output / f"{name}.ansi").write_text(capture)
                    assert plain.count(args.label) == 1, "Duplicate label"
                    assert all(columns(line.rstrip()) <= width for line in plain.splitlines()), "Layout overflow"
                    row = next(line for line in capture.splitlines() if args.label in esc.sub("", line))
                    prefix, rest = row.split(args.label, 1)
                    assert color_matches(prefix, rgb), "Color mismatch; terminal palette/quantization may require visual verification"
                    assert "\x1b[" in rest, "Color reset missing"
                    row_number = next(i + 1 for i, line in enumerate(plain.splitlines()) if args.label in line)
                    assert row_number >= 20, "Label not near footer"
                    assert args.directory_text in plain, "Directory information missing"
                    assert tmux("show-option", "-gv", "status").strip() == "off"
                    tmux("send-keys", "-l", "-t", name, "footer verification (unsent)")
                    deadline = time.monotonic() + 5
                    while True:
                        draft = tmux("capture-pane", "-p", "-e", "-t", name)
                        draft_plain = esc.sub("", draft)
                        if "footer verification (unsent)" in draft_plain:
                            break
                        if time.monotonic() > deadline:
                            raise AssertionError("Unsent draft missing")
                        time.sleep(.1)
                    assert draft_plain.count(args.label) == 1, "Draft label missing/duplicated"
                    assert all(columns(line.rstrip()) <= width for line in draft_plain.splitlines()), "Draft layout overflow"
                    (args.output / f"{name}-draft.ansi").write_text(draft)
                    results.append({"case": name, "label": args.label, "requested_color": args.color, "row": row_number, "unsent_draft": True, "passed": True})
                    tmux("send-keys", "-t", name, "C-c", check=False)
                    tmux("kill-session", "-t", name, check=False)
        finally:
            tmux("kill-server", check=False)
    (args.output / "results.json").write_text(json.dumps(results, indent=2) + "\n")
    print(json.dumps(results, indent=2))


if __name__ == "__main__":
    main()