#!/usr/bin/env python3
"""Checks a built MSI for the mistakes that cannot be caught without Windows (run by build-msi.sh and CI).

  verify-msi.py <file.msi>
"""
import os
import subprocess
import sys
import tempfile

DEFERRED = 0x400
IN_SCRIPT_NO_IMPERSONATE = 0x800


def tables(msi):
    with tempfile.TemporaryDirectory() as folder:
        subprocess.run(["msidump", "-t", "-d", folder, os.path.abspath(msi)], check=True, capture_output=True, cwd=folder)
        result = {}
        for name in (n for n in os.listdir(folder) if n.endswith(".idt")):
            with open(os.path.join(folder, name), "rb") as f:
                raw = f.read()
            lines = raw.decode("utf-8", errors="replace").splitlines()
            header = lines[0].split("\t")
            result[name[:-4]] = ([dict(zip(header, row.split("\t"))) for row in lines[3:] if row], raw)
        return result


def main(msi):
    t = tables(msi)
    errors = []

    def rows(name):
        return t.get(name, ([], b""))[0]

    for name, (_, raw) in t.items():
        if any(b > 127 for b in raw):
            errors.append(f"{name}: indeholder ikke-ASCII-tegn (databasen er codepage-neutral)")

    sequence = {r["Action"]: int(r["Sequence"]) for r in rows("InstallExecuteSequence")}
    actions = {r["Action"]: int(r["Type"]) for r in rows("CustomAction")}
    start, end = sequence["InstallInitialize"], sequence["InstallFinalize"]
    for action, kind in actions.items():
        if kind & 0x3F == 50 and not kind & DEFERRED:
            errors.append(f"{action}: kører et program uden at være deferred (ville køre som brugeren, uden rollback)")
        if action not in sequence:
            errors.append(f"{action}: er ikke i InstallExecuteSequence")
        elif kind & DEFERRED and not start < sequence[action] < end:
            errors.append(f"{action}: deferred, men ligger uden for InstallInitialize..InstallFinalize ({sequence[action]})")
        elif kind & DEFERRED and not kind & IN_SCRIPT_NO_IMPERSONATE:
            errors.append(f"{action}: deferred uden NoImpersonate (kører ikke som SYSTEM)")

    def after(action, standard):
        if sequence.get(action, 0) <= sequence[standard]:
            errors.append(f"{action} skal ligge efter {standard}")

    after("SetDataFolderAcl", "InstallServices")   # the virtual service account must exist
    after("CreateUpdateTask", "InstallFiles")
    after("OpenFirewall", "ReplaceFirewallRule")
    after("RemoveExistingProducts", "InstallExecute")  # upgrade in place: settings files are kept
    for action in ("DeleteUpdateTask", "CloseFirewall"):
        condition = next(r["Condition"] for r in rows("InstallExecuteSequence") if r["Action"] == action)
        if "UPGRADINGPRODUCTCODE" not in condition:
            errors.append(f"{action}: skal ikke køre, når en opgradering fjerner den gamle version")

    components = {r["Component"]: r for r in rows("Component")}
    for name, bits in (("AgentSettings", 0x90), ("WebSettings", 0x90), ("AgentIni", 0x10), ("WebIni", 0x10)):
        if int(components[name]["Attributes"]) & bits != bits:
            errors.append(f"{name}: mangler Permanent/NeverOverwrite")
    if not components["AgentServiceStart"]["Condition"]:
        errors.append("AgentServiceStart: mangler betingelse")
    if any(int(r["Attributes"]) & 0x100 == 0 for r in components.values()):
        errors.append("Komponenter uden 64-bit-attribut")

    for service in rows("ServiceInstall"):
        if int(service["ErrorControl"]) & 0x8000 == 0:
            errors.append(f"{service['Name']}: tjenesten er ikke Vital")

    if not any(r["Feature_"] == "UpdateTask" for r in rows("Condition")):
        errors.append("UpdateTask: mangler betingelsen, der bevarer opgaven ved opgradering")
    if not any(r["Value"].startswith("#%") for r in rows("Registry") if r["Name"] == "EventMessageFile"):
        errors.append("EventMessageFile er ikke REG_EXPAND_SZ")
    if not any(r["Name"] == "Installer" and r["Value"] == "msi" for r in rows("Registry")):
        errors.append("Registreringen Installer=msi mangler (opdateringer ville installere zip-pakker oven i MSI'en)")
    if not any(int(r["Attributes"]) & 1 for r in rows("Upgrade") if r["ActionProperty"] == "OLDVERSIONFOUND"):
        errors.append("Upgrade: MigrateFeatures mangler")

    for error in errors:
        print("FEJL:", error)
    print(f"{os.path.basename(msi)}: {len(components)} komponenter, {len(rows('File'))} filer, {len(errors)} fejl")
    return 1 if errors else 0


if __name__ == "__main__":
    sys.exit(main(sys.argv[1]))