#!/usr/bin/env python3
"""Strict synthetic command boundary; only the private /tmp fixture is writable."""
import json
import os
from pathlib import Path
import signal
import sys

name = Path(sys.argv[0]).name
args = sys.argv[1:]
root = Path('/tmp/fixture')
state_path = root / 'state.json'
state = json.loads(state_path.read_text())
fail = os.environ.get('CASE_FAIL', '')
nvme = os.environ.get('CASE_STYLE', '') == 'nvme'
disk_path = '/dev/nvme9n9' if nvme else '/dev/target'
efi_path = disk_path + ('p1' if nvme else '1')
root_path = disk_path + ('p2' if nvme else '2')
with (root / 'calls').open('a') as stream:
    stream.write(name + ' ' + ' '.join(args) + '\n')

def save():
    state_path.write_text(json.dumps(state))

def die(message):
    print(message, file=sys.stderr)
    sys.exit(47)

if fail == name or fail == name + ':inspection' and name in ('lsblk', 'findmnt', 'swapon'):
    die('injected failure')
if name == 'readlink':
    if args[:2] != ['-e','--'] or len(args) != 3 or args[2] not in (disk_path,'/dev/alias',efi_path):
        die('unexpected readlink')
    print(efi_path if args[2] == efi_path else disk_path)
elif name == 'lsblk':
    if args[:5] != ['--json','--tree','--bytes','--output','PATH,TYPE,MAJ:MIN,SIZE,MODEL,SERIAL,WWN,MOUNTPOINTS,PKNAME,PARTN'] or len(args) != 6:
        die('unexpected lsblk args')
    target = args[5]
    state['inspections'] = state.get('inspections', 0) + (target == disk_path)
    save()
    disk = {'path':disk_path,'type':'disk','maj:min':'8:16','size':100*1024**3,'model':'SYNTHETIC','serial':'TEST-NOT-REAL','wwn':None,'mountpoints':[None]}
    if fail == 'identity_change' and state['inspections'] >= 2:
        disk['maj:min'] = '8:20'
    if state['partitioned']:
        disk['children'] = [
            {'path':efi_path,'type':'part','maj:min':'8:17','size':1024**3,'partn':1,'pkname':Path(disk_path).name,'mountpoints':[None]},
            {'path':root_path,'type':'part','maj:min':'8:18','size':99*1024**3,'partn':2,'pkname':Path(disk_path).name,'mountpoints':[None]},
        ]
        if fail == 'bad_partitions': disk['children'][1]['partn'] = 3
    if fail == 'mounted_child': disk['children'] = [{'path':'/dev/target1','type':'part','maj:min':'8:17','size':1024**3,'mountpoints':['/work']}]
    if fail == 'wrong_type': disk['type'] = 'rom'
    if target == efi_path: disk = {'path':efi_path,'type':'part','maj:min':'8:17','size':1024**3,'mountpoints':[None]}
    if target == '/dev/live': disk = {'path':'/dev/live','type':'part','maj:min':'8:99','size':8*1024**3,'pkname':'live','mountpoints':['/run/archiso/bootmnt']}
    if target not in (disk_path,efi_path,'/dev/live'): die('unexpected lsblk target')
    print(json.dumps({'blockdevices':[disk]}))
elif name == 'findmnt':
    if args != ['--json','--output','TARGET,SOURCE,MAJ:MIN,FSTYPE,OPTIONS,ID']:
        die('unexpected findmnt')
    entries = [{'target':'/','source':'/dev/live','maj:min':'8:99','fstype':'ext4','options':'rw'}, {'target':'/run/archiso','source':'/dev/live','maj:min':'8:99','fstype':'ext4','options':'rw'}]
    if fail in ('overlay_live','overlay_unmapped'):
        entries[0].update({'source':'overlay','maj:min':'0:99','fstype':'overlay',
                           'options':'rw,lowerdir=/run/archiso/bootmnt/airootfs,upperdir=/run/archiso/cowspace/upper,workdir=/run/archiso/cowspace/work'})
        if fail == 'overlay_live':
            entries.append({'target':'/run/archiso/bootmnt','source':'/dev/live','maj:min':'8:99','fstype':'iso9660','options':'ro'})
            entries.append({'target':'/run/archiso/cowspace','source':'tmpfs','maj:min':'0:98','fstype':'tmpfs','options':'rw'})
    if fail == 'source_target': entries[0]['maj:min'] = '8:16'
    if fail == 'mounted_disk': entries.append({'target':'/work','source':'/dev/target1','maj:min':'8:17','fstype':'ext4'})
    if fail == 'mnt_occupied': entries.append({'target':'/mnt/other','source':'/dev/live','maj:min':'8:99','fstype':'ext4'})
    if fail == 'swapfile': entries.append({'target':'/work','source':'/dev/target2','maj:min':'8:18','fstype':'ext4'})
    entries += state['mounts']
    print(json.dumps({'filesystems':entries}))
elif name == 'swapon':
    if args != ['--show=NAME','--noheadings','--raw']: die('unexpected swapon')
    if fail == 'swap_partition': print(efi_path)
    elif fail == 'swapfile': print('/work/swapfile')
elif name in ('wipefs','parted','partprobe','udevadm','mkfs.fat','mkfs.btrfs','btrfs','mount','umount'):
    if fail == name or fail == name + ':mutate': die('injected mutation failure')
    if name == 'wipefs' and args != ['-af','--',disk_path]: die('unexpected wipefs')
    if name == 'parted':
        allowed = (
            ['-s',disk_path,'mklabel','gpt'],
            ['-s',disk_path,'mkpart','ESP','fat32','1MiB','1025MiB'],
            ['-s',disk_path,'set','1','esp','on'],
            ['-s',disk_path,'mkpart','ARCH','btrfs','1025MiB','100%'],
        )
        if args not in allowed: die('unexpected parted')
        if args == ['-s',disk_path,'mkpart','ARCH','btrfs','1025MiB','100%']:
            state['partitioned'] = True; save()
    if name == 'partprobe' and args != [disk_path]: die('unexpected partprobe')
    if name == 'partprobe' and fail in ('signal_INT','signal_TERM'):
        os.kill(os.getppid(), signal.SIGINT if fail == 'signal_INT' else signal.SIGTERM)
        sys.exit(130 if fail == 'signal_INT' else 143)
    if name == 'udevadm' and args != ['settle']: die('unexpected udevadm')
    if name == 'mkfs.fat' and args != ['-F','32','-n','EFI',efi_path]: die('unexpected mkfs.fat')
    if name == 'mkfs.btrfs' and args != ['-f','-L','ARCH',root_path]: die('unexpected mkfs.btrfs')
    if name == 'btrfs':
        if fail == 'snapshot_conflict' and args[-1] == '/mnt/@/.snapshots': Path(args[-1]).mkdir(exist_ok=True)
        allowed = {'/mnt/@','/mnt/@home','/mnt/@log','/mnt/@pkg','/mnt/@/.snapshots'}
        if args[:2] != ['subvolume','create'] or len(args) != 3 or args[2] not in allowed or Path(args[2]).exists():
            die('subvolume destination already exists or invalid')
        Path(args[2]).mkdir()
    if name == 'mount':
        if fail in ('mount:third','mount_cleanup_fail','mount_replaced') and len(state['mounts']) == 1 and state.get('mount_count', 0) >= 2:
            if fail == 'mount_replaced':
                state['mounts'][0]['id'] += 500
                save()
            die('injected mount failure')
        if args[0] == '-o':
            expected_options = {'rw,relatime,ssd,discard=async,space_cache=v2,subvol='+v for v in ('@','@home','@log','@pkg','@/.snapshots')}
            if len(args) != 4 or args[1] not in expected_options:
                die('unexpected mount options')
            source, target = args[2:]
            options = args[1]
        else:
            if len(args) != 2: die('unexpected mount')
            source, target = args
            options = 'rw'
        allowed_mounts = {('/mnt',root_path),('/mnt/home',root_path),('/mnt/var/log',root_path),
                          ('/mnt/var/cache/pacman/pkg',root_path),('/mnt/.snapshots',root_path),
                          ('/mnt/boot',efi_path)}
        if (target,source) not in allowed_mounts:
            die('unexpected mount source/target')
        if fail == 'canonical_subvol':
            options = options.replace('subvol=', 'subvol=/')
        state['mount_count'] = state.get('mount_count', 0) + 1
        state['mounts'].append({'target':target,'source':source,'maj:min':'8:17' if source.endswith('1') else '8:18','fstype':'btrfs' if source.endswith('2') else 'vfat','options':options,'id':100+state['mount_count']})
        save()
    if name == 'umount':
        allowed_targets = {'/mnt','/mnt/home','/mnt/var/log','/mnt/var/cache/pacman/pkg','/mnt/.snapshots','/mnt/boot'}
        if len(args) != 2 or args[0] != '--' or args[1] not in allowed_targets: die('unexpected umount')
        if fail == 'mount_cleanup_fail' and args[1] == '/mnt' and state.get('mount_count', 0) >= 2:
            die('injected cleanup failure')
        state['mounts'] = [m for m in state['mounts'] if m['target'] != args[1]]
        save()
else:
    die('unknown command')