import streamlit as st
import streamlit_ace as st_ace
from pathlib import Path

from backend.managers.file_manager import FileManager
from backend.managers.execution_engine import ExecutionEngine
from backend.managers.debug_logger import DebugLogger

LANG_MAP = {
    ".py": "python", ".tex": "latex", ".js": "javascript",
    ".html": "html", ".css": "css", ".sh": "bash",
    ".json": "json", ".yaml": "yaml", ".yml": "yaml"
    }


# ── Modals ────────────────────────────────────────────────────────────────────

@st.dialog("Rename File")
def _rename_dialog(file_path: str):
    fm = FileManager()
    st.write(f"Current name: **{Path(file_path).name}**")
    new_name = st.text_input("New name:", value=Path(file_path).stem)

    col1, col2 = st.columns(2)
    with col1:
        if st.button("Confirm", type="primary", use_container_width=True):
            if not new_name.strip():
                st.warning("Please enter a name.")
            elif "/" in new_name or "\\" in new_name:
                st.warning("Name must not contain slashes.")
            else:
                if fm.rename_file(file_path, new_name.strip()):
                    ext = Path(file_path).suffix
                    new_file_path = str(Path(file_path).parent / (Path(new_name.strip()).stem + ext))
                    i = st.session_state.open_files.index(file_path)
                    st.session_state.open_files[i] = new_file_path
                    st.session_state.files_content[new_file_path] = \
                        st.session_state.files_content.pop(file_path)
                    if st.session_state.active_file == file_path:
                        st.session_state.active_file = new_file_path
                    st.rerun()
                else:
                    st.error("Rename failed. Check that the file still exists.")
    with col2:
        if st.button("Cancel", use_container_width=True):
            st.rerun()


@st.dialog("Delete File")
def _delete_dialog(file_path: str):
    fm = FileManager()
    st.warning(f"Delete **{Path(file_path).name}**? This cannot be undone.")

    col1, col2 = st.columns(2)
    with col1:
        if st.button("Delete", type="primary", use_container_width=True):
            if fm.delete_file(file_path):
                st.session_state.open_files.remove(file_path)
                st.session_state.files_content.pop(file_path, None)
                if st.session_state.active_file == file_path:
                    st.session_state.active_file = (
                        st.session_state.open_files[0]
                        if st.session_state.open_files else None
                    )
                st.rerun()
            else:
                st.error("Delete failed. Check that the file still exists.")
    with col2:
        if st.button("Cancel", use_container_width=True):
            st.rerun()


def run_active_file():
    active_file = st.session_state.active_file

    if not active_file:
        st.warning("No active file to run.")
        return
    
    execution_engine = ExecutionEngine()
    debug_logger = DebugLogger()

    debug_logger.log(f"Executing code from {active_file}...")

    with st.spinner(f"Running {Path(active_file).name}..."):
        output = execution_engine.run_code(Path(active_file))

    debug_logger.log("Execution completed.")
    
    st.session_state.code_execution_output = {
        "stdout": output["stdout"],
        "stderr": output["stderr"],
        "return_code": output["rc"]
    }
    result = st.session_state.code_execution_output
    return result

def render_editor():
    st.subheader("Code Editor")

    if not st.session_state.open_files:
        st.info("Please select a file to edit.")
        return

    fm = FileManager()

    # ── Tab bar via st.tabs() ─────────────────────────────────────────────────
    tab_names = [Path(f).name for f in st.session_state.open_files]
    tabs = st.tabs(tab_names)

    for idx, file_path in enumerate(st.session_state.open_files):
        with tabs[idx]:
            if file_path not in st.session_state.files_content:
                st.session_state.files_content[file_path] = fm.read_file(Path(file_path))

            file_language = LANG_MAP.get(Path(file_path).suffix, "text")

            code = st_ace.st_ace(
                value=st.session_state.files_content[file_path],
                language=file_language,
                theme="monokai",
                key=f"code_editor_{file_path}",
                auto_update=True,
                height=400,
            )

            if code != st.session_state.files_content[file_path]:
                st.session_state.files_content[file_path] = code

            cols = st.columns([1, 1, 1, 1])
            with cols[0]:
                if st.button("Save Changes", key=f"save_{file_path}"):
                    if fm.save_file(file_path, code):
                        st.success("File saved successfully!")

            with cols[1]:
                if st.button("Close File", key=f"close_{file_path}"):
                    st.session_state.open_files.remove(file_path)
                    st.session_state.files_content.pop(file_path, None)
                    st.session_state.active_file = (
                        st.session_state.open_files[0]
                        if st.session_state.open_files else None
                    )
                    st.rerun()

            with cols[2]:
                if st.button("Rename File", key=f"rename_{file_path}"):
                    _rename_dialog(file_path)

            with cols[3]:
                if st.button("Delete File", key=f"delete_{file_path}"):
                    _delete_dialog(file_path)

    if st.button("▶ Run Code", key="run_code"):
            result = run_active_file()
            if not result:
                st.stop()
    
            st.subheader("Execution Output")
    
            if result["return_code"] == 0:
                st.success(f"Exit code: {result['return_code']}")
            else:
                st.error(f"Exit code: {result['return_code']}")
            
            if result["stdout"]:
                st.text_area(
                    "Standard Output", 
                    value=result["stdout"], 
                    height=200,
                    disabled=True, 
                    key="run_stdout")
                
            if result["stderr"]:
                st.text_area(
                    "Standard Error", 
                    value=result["stderr"], 
                    height=200,
                    disabled=True, 
                    key="run_stderr")
            if not result["stdout"] and not result["stderr"]:
                st.info("No output produced by the code execution.")

    
    
if __name__ == "__main__":
    render_editor()