import * as React from "react";
import { Box, Typography, Button, Container, Grid, Paper, alpha } from "@mui/material";
import { useTheme } from "@mui/material/styles";
import { useNavigate } from "react-router-dom";
import ReceiptLongIcon from "@mui/icons-material/ReceiptLong";
import SyncIcon from "@mui/icons-material/Sync";
import AccountBalanceWalletIcon from "@mui/icons-material/AccountBalanceWallet";
import AccountCircleIcon from "@mui/icons-material/AccountCircle";
import ArrowForwardIcon from "@mui/icons-material/ArrowForward";
import { useAuth } from "../react-auth";

interface FeatureCardProps {
  icon: React.ReactNode;
  title: string;
  description: string;
  path: string;
}

function FeatureCard({ icon, title, description, path }: FeatureCardProps) {
  const navigate = useNavigate();
  const theme = useTheme();

  return (
    <Paper
      elevation={0}
      onClick={() => navigate(path)}
      sx={{
        p: 3,
        borderRadius: 3,
        border: "1px solid",
        borderColor: "divider",
        cursor: "pointer",
        height: "100%",
        display: "flex",
        flexDirection: "column",
        transition: "border-color 180ms ease, box-shadow 180ms ease, transform 180ms ease",
        "&:hover": {
          borderColor: "transparent",
          transform: "translateY(-2px)",
          boxShadow: `0 8px 24px ${alpha(theme.palette.common.black, theme.palette.mode === "dark" ? 0.35 : 0.08)}`,
          "& .feature-arrow": {
            opacity: 1,
            transform: "translateX(0)",
          },
        },
      }}
    >
      <Box
        sx={{
          width: 40,
          height: 40,
          borderRadius: 2,
          display: "flex",
          alignItems: "center",
          justifyContent: "center",
          backgroundColor: "action.hover",
          color: "primary.main",
          mb: 2,
        }}
      >
        {icon}
      </Box>

      <Typography variant="subtitle1" fontWeight={600} sx={{ mb: 0.75 }}>
        {title}
      </Typography>

      <Typography variant="body2" color="text.secondary" sx={{ flex: 1, lineHeight: 1.6 }}>
        {description}
      </Typography>

      <Box
        className="feature-arrow"
        sx={{
          mt: 2,
          display: "flex",
          alignItems: "center",
          gap: 0.5,
          color: "primary.main",
          fontWeight: 600,
          opacity: 0,
          transform: "translateX(-4px)",
          transition: "opacity 180ms ease, transform 180ms ease",
        }}
      >
        <Typography variant="caption" fontWeight={600} color="primary">
          Open
        </Typography>
        <ArrowForwardIcon sx={{ fontSize: 14 }} />
      </Box>
    </Paper>
  );
}

export default function Home() {
  const navigate = useNavigate();
  const { currentUser } = useAuth();

  const features = [
    {
      icon: <ReceiptLongIcon />,
      title: "Expenses",
      description:
        "Browse every transaction imported from your accounts — grouped by month, with entity, account, tags, and amount at a glance.",
      path: "/expenses",
    },
    {
      icon: <SyncIcon />,
      title: "Fetch Requests",
      description:
        "Upload bank statements or configure email ingestion to auto-import transactions. Track pipeline status from pending through to completion.",
      path: "/fetch-requests",
    },
    {
      icon: <AccountBalanceWalletIcon />,
      title: "Accounts & Entities",
      description:
        "Manage your accounts, expenses, tags, and payors through the OpenAPI-driven admin panel with full CRUD and server-side filters.",
      path: "/admin",
    },
    {
      icon: <AccountCircleIcon />,
      title: "Profile",
      description:
        "View and edit your user profile — username, email, and account preferences — from the profile page.",
      path: "/profile/me",
    },
  ];

  return (
    <Box sx={{ width: "100%" }}>
      <Container maxWidth="lg" sx={{ py: { xs: 6, md: 10 } }}>
        <Box sx={{ maxWidth: 680, mx: { xs: "auto", md: 0 }, textAlign: { xs: "center", md: "left" } }}>
          <Typography
            variant="overline"
            sx={{ color: "primary.main", mb: 1.5, display: "block", fontWeight: 700 }}
          >
            Khata · Financial Ledger
          </Typography>

          <Typography
            variant="h1"
            sx={{
              color: "text.primary",
              fontSize: { xs: "2.25rem", md: "3.25rem" },
              letterSpacing: "-0.03em",
              mb: 2,
            }}
          >
            Your intelligent, extensible financial ledger.
          </Typography>

          <Typography
            variant="body1"
            color="text.secondary"
            sx={{ maxWidth: 540, lineHeight: 1.7, fontSize: "1.0625rem" }}
          >
            Import transactions from bank statements, enrich them with entity and tag intelligence,
            and stay on top of your cashflow — all in one place.
          </Typography>

          <Box sx={{ mt: 4, display: "flex", gap: 2, justifyContent: { xs: "center", md: "flex-start" }, flexWrap: "wrap" }}>
            <Button
              variant="contained"
              size="large"
              endIcon={<ArrowForwardIcon />}
              onClick={() => navigate(currentUser ? "/fetch-requests" : "/login")}
              sx={{ px: 3.5, py: 1.4, fontWeight: 600 }}
            >
              {currentUser ? "Enter App" : "Get Started"}
            </Button>
            <Button
              variant="outlined"
              size="large"
              onClick={() => navigate("/fetch-requests")}
              sx={{ px: 3.5, py: 1.4, fontWeight: 600 }}
            >
              Import Data
            </Button>
          </Box>
        </Box>

        <Grid container spacing={3} sx={{ mt: { xs: 4, md: 8 } }}>
          {features.map((f) => (
            <Grid key={f.title} item xs={12} sm={6} md={3}>
              <FeatureCard {...f} />
            </Grid>
          ))}
        </Grid>
      </Container>
    </Box>
  );
}