#!/usr/bin/python3

import os, sys, re
import filecmp
from glob import glob
from mako.template import Template
import subprocess
import yaml


def backupProj(project):
    print(f"Running backup for project {project}.")
    # loop env.volumes & secrets.postgres


def getImageId (image):
    return subprocess.run(["podman", "image", "inspect", "--format", "{{.Id}}", image], capture_output=True, text=True).stdout.strip()


def getUid(service):
    if service in env['users'].keys():
        user = env['users'][service] + env['uid_shift']
    else:
        user = 1000
    return user


def pullProj(project):
    print(f"Pulling images for project {project}.")
    
    with open(f"projects/{project}/compose.yaml.rendered", 'r') as composefile:
        images = re.findall('(?<=image:\\s).+', composefile.read())

    pulledImages = []
    for image in images:
        currentId = getImageId(image)
        subprocess.run(["podman", "pull", image])
        pulledId = getImageId(image)
        if currentId != pulledId:
            pulledImages += image
            print(f"Pulled new version of image {image}.")
        else:
            print(f"No update available for image {image}.")

    return pulledImages


def renderFile(templateFile):
    print(f"Rendering file {templateFile}.")

    renderedFilename = re.sub('\\.mako$', '.rendered', templateFile)

    template = Template(filename=templateFile)

    outputFile = open(renderedFilename, "w")
    outputFile.write(template.render(env=env, secrets=secrets))
    outputFile.close()


def setCertPerms(service):
    for path in ["/etc/letsencrypt", "/etc/letsencrypt/live", "/etc/letsencrypt/archive"]:
        setOwner(path, 0, 0)
        setPerms(path, 751)

    pkeyFile = env['certs'][service]['pkey']   
    
    domain_dir = re.search('.+(?=\\/.+$)', pkeyFile).group(0)
    for path in [domain_dir, re.sub('live', 'archive', domain_dir)]:
        setOwner(path, env['host_uid'], getUid(service))
        setPerms(path, 550)

    setOwner(pkeyFile, 0, getUid(service))
    setPerms(pkeyFile, 640)


def setNftables():
    renderFile("nftables.conf.mako")
    if not filecmp.cmp("nftables.conf.rendered", "/etc/nftables.conf"):
        print("nftables.conf changed, copying new version.")
        sudoRun(["cp", "nftables.conf.rendered", "/etc/nftables.conf"])
        sudoRun(["systemctl", "restart", "nftables"])
    else:
        print("nftables.conf unchanged.")


def setOwner(path, uid=None, gid=None):
    stat = os.stat(path)
    if uid is None:
        uid = stat.st_uid
    if gid is None:
        gid = stat.st_gid    

    if stat.st_uid != uid or stat.st_gid != gid:
        print(f"Changing ownership of {path} to {uid}:{gid} from {stat.st_uid}:{stat.st_gid}.")
        sudoRun(["chown", f"{uid}:{gid}", path])
    else:
        print(f"Ownership of {path} already set to {uid}:{gid}.")


def setPerms(path, mode):
    mode = str(mode)
    stat = os.stat(path)
    curMode = oct(stat.st_mode)[-3:]
    if mode != curMode:
        print(f"Changing permissions of {path} to {mode} from {curMode}.")
        if stat.st_uid == env['host_uid']:
            subprocess.run(["chmod", mode, path])
        else:
            subprocess.run(["sudo", "chmod", mode, path])
    else:
        print(f"Permissions of {path} already set to {mode}.")


def setupProj(project):
    print(f"Running setup for project {project}.")

    backupProj(project)

    if project in env['certs'].keys():
        setCertPerms(project)
        
    for templateFile in glob(f"projects/{project}/*.mako", include_hidden=True):
        renderFile(templateFile)
        renderedFilename = re.sub('\\.mako$', '.rendered', templateFile)
        setPerms(renderedFilename, 640)
        setOwner(renderedFilename, env['host_uid'], getUid(project))

    upProj(project)


def sudoRun(args): 
    child = subprocess.Popen(["sudo"] + args, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)
    if re.search('^\\[sudo\\] password for .+', child.stdout.read().strip()):
        child.communicate(input=input().encode())[0]


def upProj(project):
    print(f"Creating & starting stack for project {project}.")
    if subprocess.run(["podman", "container", "exists", project]).returncode == 0:
        subprocess.run(["podman-compose", "-f", f"projects/{project}/compose.yaml.rendered", "down"])
    subprocess.run(["podman-compose", "-f", f"projects/{project}/compose.yaml.rendered", "up", "-d"])


def updateProj(project):
    if not os.path.isfile(f"projects/{project}/compose.yaml.rendered"):
        setupProj(project)
            
    print(f"Running update for project {project}.")
    
    if len(pullProj(project)) > 0:
        backupProj(project)
        upProj(project)


def main():
    envFile = "pyenv.yml"
    secretsFile = "pysecrets.yml"
    
    os.chdir(os.path.realpath(sys.path[0]))

    with open(envFile, 'r') as envfile, open(secretsFile, 'r') as secretsfile:
        global env, secrets
        env = yaml.safe_load(envfile)
        env = yaml.safe_load(Template(filename=envFile).render(env=env))
        secrets = yaml.safe_load(secretsfile)
        
    setOwner(secretsFile, env['host_uid'], env['host_uid'])
    setPerms(secretsFile, 600)

    print("\nChoose action:")
    print("[1/S] Setup project")
    print("[2/U] Update project")
    print("[3/B] Backup project")

    action = ''
    while action == '':
        action = input("Action: ")

    projects = os.listdir("projects")
    print(f"\nProjects list: {projects}")

    target_projects = input("Target compose project(s), space separated, leave empty to target all: ")

    if target_projects == '':
        target_projects = projects
    else:
        target_projects = target_projects.split(' ')
    print(f"Target projects: {target_projects}")

    setNftables()

    match action:
        case '1' | 'S':
            for project in target_projects:
                try:
                    print()
                    setupProj(project)
                except Exception as e:
                    print(e, file=sys.stderr)
                    print(f"Failed to setup project {project}.", file=sys.stderr)

        case '2' | 'U':
            for project in target_projects:
                try:
                    print()
                    updateProj(project)
                except Exception as e:
                    print(e, file=sys.stderr)
                    print(f"Failed to update project {project}.", file=sys.stderr)


if __name__ == "__main__":
    main()