# -*- coding: utf-8 -*-

# Copyright 2019-2022 Mike Fährmann
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation.

"""Write metadata to external files"""

from .common import PostProcessor
from .. import util, formatter
import sys
import os


class MetadataPP(PostProcessor):

    def __init__(self, job, options):
        PostProcessor.__init__(self, job)

        mode = options.get("mode", "json")
        cfmt = options.get("content-format") or options.get("format")
        if mode == "tags":
            self.write = self._write_tags
            ext = "txt"
        elif mode == "modify":
            self.run = self._run_modify
            self.fields = {
                name: formatter.parse(value, None, util.identity).format_map
                for name, value in options.get("fields").items()
            }
            ext = None
        elif mode == "delete":
            self.run = self._run_delete
            self.fields = options.get("fields")
            ext = None
        elif mode == "custom" or cfmt:
            self.write = self._write_custom
            if isinstance(cfmt, list):
                cfmt = "\n".join(cfmt) + "\n"
            self._content_fmt = formatter.parse(cfmt).format_map
            ext = "txt"
        else:
            self.write = self._write_json
            self.indent = options.get("indent", 4)
            self.ascii = options.get("ascii", False)
            ext = "json"

        directory = options.get("directory")
        if directory:
            self._directory = self._directory_custom
            sep = os.sep + (os.altsep or "")
            self._metadir = util.expand_path(directory).rstrip(sep) + os.sep

        filename = options.get("filename")
        extfmt = options.get("extension-format")
        if filename:
            if filename == "-":
                self.run = self._run_stdout
            else:
                self._filename = self._filename_custom
                self._filename_fmt = formatter.parse(filename).format_map
        elif extfmt:
            self._filename = self._filename_extfmt
            self._extension_fmt = formatter.parse(extfmt).format_map
        else:
            self.extension = options.get("extension", ext)

        events = options.get("event")
        if events is None:
            events = ("file",)
        elif isinstance(events, str):
            events = events.split(",")
        job.register_hooks({event: self.run for event in events}, options)

        archive = options.get("archive")
        if archive:
            extr = job.extractor
            archive = util.expand_path(archive)
            archive_format = (
                options.get("archive-prefix", extr.category) +
                options.get("archive-format", "_MD_" + extr.archive_fmt))
            try:
                if "{" in archive:
                    archive = formatter.parse(archive).format_map(
                        job.pathfmt.kwdict)
                self.archive = util.DownloadArchive(
                    archive, archive_format, "_archive_metadata")
            except Exception as exc:
                self.log.warning(
                    "Failed to open download archive at '%s' ('%s: %s')",
                    archive, exc.__class__.__name__, exc)
            else:
                self.log.debug("Using download archive '%s'", archive)
        else:
            self.archive = None

        self.mtime = options.get("mtime")

    def run(self, pathfmt):
        archive = self.archive
        if archive and archive.check(pathfmt.kwdict):
            return

        directory = self._directory(pathfmt)
        path = directory + self._filename(pathfmt)

        try:
            with open(path, "w", encoding="utf-8") as fp:
                self.write(fp, pathfmt.kwdict)
        except FileNotFoundError:
            os.makedirs(directory, exist_ok=True)
            with open(path, "w", encoding="utf-8") as fp:
                self.write(fp, pathfmt.kwdict)

        if archive:
            archive.add(pathfmt.kwdict)

        if self.mtime:
            mtime = pathfmt.kwdict.get("_mtime")
            if mtime:
                util.set_mtime(path, mtime)

    def _run_stdout(self, pathfmt):
        self.write(sys.stdout, pathfmt.kwdict)

    def _run_modify(self, pathfmt):
        kwdict = pathfmt.kwdict
        for key, func in self.fields.items():
            obj = kwdict
            try:
                while "[" in key:
                    name, _, key = key.partition("[")
                    obj = obj[name]
                    key = key.rstrip("]")
                obj[key] = func(kwdict)
            except Exception:
                pass

    def _run_delete(self, pathfmt):
        kwdict = pathfmt.kwdict
        for key in self.fields:
            obj = kwdict
            try:
                while "[" in key:
                    name, _, key = key.partition("[")
                    obj = obj[name]
                    key = key.rstrip("]")
                del obj[key]
            except Exception:
                pass

    def _directory(self, pathfmt):
        return pathfmt.realdirectory

    def _directory_custom(self, pathfmt):
        return os.path.join(pathfmt.realdirectory, self._metadir)

    def _filename(self, pathfmt):
        return (pathfmt.filename or "metadata") + "." + self.extension

    def _filename_custom(self, pathfmt):
        return pathfmt.clean_path(pathfmt.clean_segment(
            self._filename_fmt(pathfmt.kwdict)))

    def _filename_extfmt(self, pathfmt):
        kwdict = pathfmt.kwdict
        ext = kwdict.get("extension")
        kwdict["extension"] = pathfmt.extension
        kwdict["extension"] = pathfmt.prefix + self._extension_fmt(kwdict)
        filename = pathfmt.build_filename(kwdict)
        kwdict["extension"] = ext
        return filename

    def _write_custom(self, fp, kwdict):
        fp.write(self._content_fmt(kwdict))

    def _write_tags(self, fp, kwdict):
        tags = kwdict.get("tags") or kwdict.get("tag_string")

        if not tags:
            return

        if isinstance(tags, str):
            taglist = tags.split(", ")
            if len(taglist) < len(tags) / 16:
                taglist = tags.split(" ")
            tags = taglist
        elif isinstance(tags, dict):
            taglists = tags.values()
            tags = []
            extend = tags.extend
            for taglist in taglists:
                extend(taglist)
            tags.sort()

        fp.write("\n".join(tags) + "\n")

    def _write_json(self, fp, kwdict):
        util.dump_json(util.filter_dict(kwdict), fp, self.ascii, self.indent)


__postprocessor__ = MetadataPP