import os
import gzip
import json

from typing import *

LANGUAGE_TAG = {
    "c"            : "// language: C",
    "c++"          : "// language: C++",
    "cpp"          : "// language: C++",
    "c#"           : "// language: C#",
    "csharp"       : "// language: C#",
    "css"          : "/* language: CSS */",
    "cuda"         : "// language: Cuda",
    "dart"         : "// language: Dart",
    "lua"          : "// language: Lua",
    "objectivec"  : "// language: Objective-C",
    "objective-c"  : "// language: Objective-C",
    "objective-c++": "// language: Objective-C++",
    "python"       : "# language: Python",
    "perl"         : "# language: Perl",
    "prolog"       : f"% language: Prolog",
    "swift"        : "// language: swift",
    "lisp"         : "; language: Lisp",
    "java"         : "// language: Java",
    "scala"        : "// language: Scala",
    "tex"          : f"% language: TeX",
    "vue"          : "<!--language: Vue-->",
    "markdown"     : "<!--language: Markdown-->",
    "html"         : "<!--language: HTML-->",
    "php"          : "// language: PHP",
    "js"           : "// language: JavaScript",
    "javascript"   : "// language: JavaScript",
    "typescript"   : "// language: TypeScript",
    "go"           : "// language: Go",
    "shell"        : "# language: Shell",
    "rust"         : "// language: Rust",
    "sql"          : "-- language: SQL",
    "kotlin"       : "// language: Kotlin",
    "vb"           : "' language: Visual Basic",
    "ruby"         : "# language: Ruby",
    "pascal"       : "// language: Pascal",
    "r"            : "# language: R",
    "fortran"      : "!language: Fortran",
    "lean"         : "-- language: Lean",
    "matlab"       : f"% language: Matlab",
    "delphi"       : "{language: Delphi}",
    "scheme"       : "; language: Scheme",
    "basic"        : "' language: Basic",
    "assembly"     : "; language: Assembly",
    "groovy"       : "// language: Groovy",
    "abap"         : "* language: Abap",
    "gdscript"     : "# language: GDScript",
    "haskell"      : "-- language: Haskell",
    "julia"        : "# language: Julia",
    "elixir"       : "# language: Elixir",
    "excel"        : "' language: Excel",
    "clojure"      : "; language: Clojure",
    "actionscript" : "// language: ActionScript",
    "solidity"     : "// language: Solidity",
    "powershell"   : "# language: PowerShell",
    "erlang"       : f"% language: Erlang",
    "cobol"        : "// language: Cobol",
}


def stream_jsonl(filename: str) -> Iterable[Dict]:
    """
    Parses each jsonl line and yields it as a dictionary
    """
    if filename.endswith(".gz"):
        with open(filename, "rb") as gzfp:
            with gzip.open(gzfp, "rt") as fp:
                for line in fp:
                    if any(not x.isspace() for x in line):
                        yield json.loads(line)
    else:
        with open(filename, "r") as fp:
            for line in fp:
                if any(not x.isspace() for x in line):
                    yield json.loads(line)


def write_jsonl(filename: str, data: Iterable[Dict], append: bool = False):
    """
    Writes an iterable of dictionaries to jsonl
    """
    if append:
        mode = "ab"
    else:
        mode = "wb"
    filename = os.path.expanduser(filename)
    if filename.endswith(".gz"):
        with open(filename, mode) as fp:
            with gzip.GzipFile(fileobj=fp, mode="wb") as gzfp:
                for x in data:
                    gzfp.write((json.dumps(x) + "\n").encode("utf-8"))
    else:
        with open(filename, mode) as fp:
            for x in data:
                fp.write((json.dumps(x) + "\n").encode("utf-8"))
                
                
def sliding_window(
    prompt_tokens: list, 
    code_tokens: list, 
    seq_len: int, 
    sliding_stride: int, 
    minimum_code_len: int = 1,
) -> Iterable[Tuple[list, list]]:
    """
    Generate a series of (prompt, code) pairs by sliding the window over the code.
    """
    prompt_len = len(prompt_tokens)
    code_len = len(code_tokens)
    total_len = prompt_len + code_len

    start_idx = max(0, prompt_len - seq_len + minimum_code_len)  # at least `minimum_code_len` code token should be in the window
    end_idx = max(0, total_len - seq_len)
    start_idx = min(start_idx, end_idx)

    for i in range(start_idx, end_idx + 1, sliding_stride):
        current_prompt = prompt_tokens[i:i + seq_len]
        current_code = code_tokens[max(i - prompt_len, 0):i - prompt_len + seq_len]
        yield current_prompt, current_code

    if (end_idx - start_idx) % sliding_stride != 0:
        current_prompt = prompt_tokens[end_idx:end_idx + seq_len]
        current_code = code_tokens[max(end_idx - prompt_len, 0):end_idx - prompt_len + seq_len]
        yield current_prompt, current_code